Unveiling novel Neocosmospora species from Thai mangroves as potent biocontrol agents against Colletotrichum species

AIMS

Neocosmospora species are saprobes, endophytes, and pathogens belonging to the family Nectriaceae. This study aims to investigate the taxonomy, biosynthetic potential, and application of three newly isolated Neocosmospora species from mangrove habitats in the southern part of Thailand using phylogeny, bioactivity screening, genome sequencing, and bioinformatics analysis.

METHODS AND RESULTS

Detailed descriptions, illustrations, and a multi-locus phylogenetic tree with large subunit ribosomal DNA (LSU), internal transcribed spacer (ITS), translation elongation factor 1-alpha (ef1-α), and RNA polymerase II second largest subunit (RPB2) regions showing the placement of three fungal strains, MFLUCC 17-0253, MFLUCC 17-0257, and MFLUCC 17-0259 clustered within the Neocosmospora clade with strong statistical support. Fungal crude extracts of the new species N. mangrovei MFLUCC 17-0253 exhibited strong antifungal activity to control Colletotrichum truncatum CG-0064, while N. ferruginea MFLUCC 17-0259 exhibited only moderate antifungal activity toward C. acutatum CC-0036. Thus, N. mangrovei MFLUCC 17-0253 was sequenced by Oxford nanopore technology. The bioinformatics analysis revealed that 49.17 Mb genome of this fungus harbors 41 potential biosynthetic gene clusters.

CONCLUSION

Two fungal isolates of Neocosmospora and a new species of N. mangrovei were reported in this study. These fungal strains showed activity against pathogenic fungi causing anthracnose in chili. In addition, full genome sequencing and bioinformatics analysis of N. mangrovei MFLUCC 17-0253 were obtained.

Sarcopenic obesity and reduced BMD in young men living with HIV: body composition and sex steroids interplay

PURPOSE

Sex steroids play a key role on male bone homeostasis and body composition (BC), their role in men living with HIV (MLWH) is less recognized. This study aimed at investigating the prevalence of low BMD, sarcopenia, and sarcopenic obesity (SO) and their relationship with sex steroids in MLWH aged < 50.

METHODS

Prospective, cross-sectional, observational study on MLWH younger than 50 (median age 47.0 years). BC and BMD were evaluated with DXA. Two different definitions of sarcopenia were applied: appendicular lean mass/height2 (ALMI) < 7.26 kg/m2 or appendicular lean mass/body weight (ALM/W) < 28.27%. Low BMD was defined for Z-score < -2.0. Sarcopenia coupled with obesity identified SO. Serum total testosterone (T) and estradiol (E2) were measured by LC-MS/MS; free testosterone (cFT) was calculated by Vermeulen equation.

RESULTS

Sarcopenia was detected in 107 (34.9%) and 44 (14.3%) out of 307 MLWH according to ALMI and ALM/W, respectively. The prevalence of SO was similar by using both ALMI (11.4%) and ALM/W (12.4%). Sarcopenic and SO MLWH had lower total T and cFT in both the definition for sarcopenia. BMD was reduced in 43/307 (14.0%). Serum E2 < 18 pg/mL was an independent contributing factor for sarcopenia, SO, and low BMD.

CONCLUSIONS

T and E2 are important determinants of BC even in MLWH. This is among the first studies investigating the distribution of obesity phenotypes and the prevalence of SO among MLWH showing that SO is present in 11-12% of enrolled MLWH regardless of the definition used. However, deep differences emerged using two different diagnostic definitions.

CO Oxidation Mechanism of Silver-Substituted Mo/Cu CO-Dehydrogenase - Analogies and Differences to the Native Enzyme

The aerobic oxidation of carbon monoxide to carbon dioxide is catalysed by the Mo/Cu-containing CO-dehydrogenase enzyme in the soil bacterium Oligotropha carboxidovorans, enabling the organism to grow on the small gas molecule as carbon and energy source. It was shown experimentally that silver can be substituted for copper in the active site of Mo/Cu CODH to yield a functional enzyme. In this study, we employed QM/MM calculations to investigate whether the reaction mechanism of the silver-substituted enzyme is similar to that of the native enzyme. Our results suggest that the Ag-substituted enzyme can oxidize CO and release CO2 following the same reaction steps as the native enzyme, with a computed rate-limiting step of 10.4 kcal/mol, consistent with experimental findings. Surprisingly, lower activation energies for C-O bond formation have been found in the presence of silver. Furthermore, comparison of rate constants for reduction of copper- and silver-containing enzymes suggests a discrepancy in the transition state stabilization upon silver substitution. We also evaluated the effects that differences in the water-active site interaction may exert on the overall energy profile of catalysis. Finally, the formation of a thiocarbonate intermediate along the catalytic pathway was found to be energetically unfavorable for the Ag-substituted enzyme. This finding aligns with the hypothesis proposed for the wild-type form, suggesting that the creation of such species may not be necessary for the enzymatic catalysis of CO oxidation.

Field output correction factors of small static field for IBA razor nanochamber

Purpose.The goal of this work is present results of field output factors (OF) using an IBA CC003 (Razor NanoChamber) and compare these results with PTW 60019 (MicroDiamond) and IBA Razor Diode. The experimental results for IBA CC003 were also compared with Monte Carlo (MC) Simulation, using Penelope and Ulysses programs. In addition, field output correction factors (kQclin,Qmsrfclin,fmsr) for IBA CC003 were derived with three different methods: (1) using PTW 60019 and IBA Razor as reference detectors; (2) comparison between MC and experimental measurements; and (3) using only MC.Material and Methods. The beam collimation included in this study were (1) square field size between 10 × 10 and 0.5 × 0.5 cm2defined by the MLC and jaws and (2) cones of different diameters. For IBA CC003 it was determined the polarity and ion collection efficiency correction factors in parallel and perpendicular orientation.Results.The results indicate (1) the variation of polarity effect with the field size is relevant for the determination of OF using IBA CC003, especially for parallel orientation; (2) there is no significant variation of the ion collection efficiency with the field size using IBA CC003 in parallel orientation; (3) OF differences between IBA CC003 and PTW 60019/IBA Razor, and experimental and MC results, increase with decreasing field size;ThekQclin,Qmsrfclin,fmsrresults indicate (1) using the first and second method,kQclin,Qmsrfclin,fmsrincrease with decreasing field size, which can be related with the influence of the volume effect and (2) using the third method,kQclin,Qmsrfclin,fmsrdecrease with decreasing field size, which can be explained by the perturbation effect.Conclusions. Our results demonstrate the need of applyingkQclin,Qmsrfclin,fmsrfor IBA CC003 forSclin≤1 cm, to compensate for volume averaging and perturbations effects.

Long-term trajectories of bone metabolism parameters and bone mineral density (BMD) in obese patients treated with metabolic surgery: a real-world, retrospective study

PURPOSE

Potential negative effects of metabolic surgery on skeletal integrity remain a concern, since long-term data of different surgical approaches are poor. This study aimed to describe changes in bone metabolism in subjects with obesity undergoing both Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG).

METHODS

A single center, retrospective, observational clinical study on real-world data was performed enrolling subjects undergoing metabolic surgery.

RESULTS

123 subjects were enrolled (males 31: females 92; ages 48.2 ± 7.9 years). All patients were evaluated until 16.9 ± 8.1 months after surgery, while a small group was evaluated up to 4.5 years. All patients were treated after surgery with calcium and vitamin D integration. Both calcium and phosphate serum levels significantly increased after metabolic surgery and remained stable during follow-up. These trends did not differ between RYGB and SG (p = 0.245). Ca/P ratio decreased after surgery compared to baseline (p < 0.001) and this decrease remained among follow-up visits. While 24-h urinary calcium remained stable across all visits, 24-h urinary phosphate showed lower levels after surgery (p = 0.014), also according to surgery technique. Parathyroid hormone decreased (p < 0.001) and both vitamin D (p < 0.001) and C-terminal telopeptide of type I collagen (p = 0.001) increased after surgery.

CONCLUSION

We demonstrated that calcium and phosphorous metabolism shows slight modification even after several years since metabolic surgery, irrespective of calcium and vitamin D supplementation. This different set point is characterized by a phosphate serum levels increase, together with a persistent bone loss, suggesting that supplementation alone may not ensure the maintenance of bone health in these patients.

Activation of the N2 molecule by means of low-valence complexes of calcium and magnesium

Nitrogen gas is a highly inert molecule and its activation under mild conditions represents a crucial goal in current research. In a recent study, the discovery of low-valence Ca(I) compounds capable of coordinating and reducing N₂ was reported [B. Rösch, T. X. Gentner, J. Langer, C. Färber, J. Eyselein, L. Zhao, C. Ding, G. Frenking and S. Harder, Science, 2021, 371, 1125]. The study of low-valence alkaline earth complexes represents a new horizon in inorganic chemistry and demonstrates examples of spectacular reactivity. For example, complexes of the [BDI]₂Mg₂ type are selective reducing reagents in both organic and inorganic synthesis reactions. To date, however, no activity of Mg(I) complexes in the activation of the nitrogen molecule has been reported. By computational studies, in the present work, we investigated the analogies and differences of low-valence Ca(I) and Mg(I) complexes in the coordination, activation and protonation of N₂. We have shown that the possibility of alkaline earth metals to employ atomic orbitals of the d type is reflected in the differences in the N₂ binding energy and its coordination mode (end-on vs. side-on), as well as in the spin state of the resulting adduct (singlet vs. triplet). These divergences are finally observed in the subsequent protonation reaction, which turned out to be prohibitive in the presence of Mg.

Novel unconventional radiotherapy techniques: Current status and future perspectives - Report from the 2nd international radiation oncology online seminar

•Improvement of therapeutic ratio by novel unconventional radiotherapy approaches.•Immunomodulation using high-dose spatially fractionated radiotherapy.•Boosting radiation anti-tumor effects by adding an immune-mediated cell killing.

Recent Theoretical Insights into the Oxidative Degradation of Biopolymers and Plastics by Metalloenzymes

Molecular modeling techniques have become indispensable in many fields of molecular sciences in which the details related to mechanisms and reactivity need to be studied at an atomistic level. This review article provides a collection of computational modeling works on a topic of enormous interest and urgent relevance: the properties of metalloenzymes involved in the degradation and valorization of natural biopolymers and synthetic plastics on the basis of both circular biofuel production and bioremediation strategies. In particular, we will focus on lytic polysaccharide monooxygenase, laccases, and various heme peroxidases involved in the processing of polysaccharides, lignins, rubbers, and some synthetic polymers. Special attention will be dedicated to the interaction between these enzymes and their substrate studied at different levels of theory, starting from classical molecular docking and molecular dynamics techniques up to techniques based on quantum chemistry.

She adapts to her student: An expert pragmatic speaker tailoring her referring expressions to the Layman listener

Communication is a dynamic process through which interlocutors adapt to each other. In the development of conversational agents, this core aspect has been put aside for several years since the main challenge was to obtain conversational neural models able to produce utterances and dialogues that at least at the surface level are human-like. Now that this milestone has been achieved, the importance of paying attention to the dynamic and adaptive interactive aspects of language has been advocated in several position papers. In this paper, we focus on how a Speaker adapts to an interlocutor with different background knowledge. Our models undergo a pre-training phase, through which they acquire grounded knowledge by learning to describe an image, and an adaptive phase through which a Speaker and a Listener play a repeated reference game. Using a similar setting, previous studies focus on how conversational models create new conventions; we are interested, instead, in studying whether the Speaker learns from the Listener's mistakes to adapt to his background knowledge. We evaluate models based on Rational Speech Act (RSA), a likelihood loss, and a combination of the two. We show that RSA could indeed work as a backbone to drive the Speaker toward the Listener: in the combined model, apart from the improved Listener's accuracy, the language generated by the Speaker features the changes that signal adaptation to the Listener's background knowledge. Specifically, captions to unknown object categories contain more adjectives and less direct reference to the unknown objects.

How general is the effect of the bulkiness of organic ligands on the basicity of metal-organic catalysts? H2-evolving Mo oxides/sulphides as case studies

Tailoring the activity of an organometallic catalyst usually requires a targeted ligand design. Tuning the ligand bulkiness and tuning the electronic properties are popular approaches, which are somehow interdependent because substituents of different sizes within ligands can determine inter alia the occurrence of different degrees of inductive effects. Ligand basicity, in particular, turned out to be a key property for the modulation of protonation reactions occurring in vacuo at the metals in complexes bearing organophosphorus ligands; however, when the same reactions take place in a polar organic solvent, their energetics becomes dependent on the trade-off between ligand basicity and bulkiness, with the polarity of the solvent playing a key role in this regard [Bancroft et al., Inorg. Chem., 1986, 25, 3675; Rovaletti et al., J. Phys. Org. Chem., 2018, 31, e3748]. In the present contribution, we carried out molecular dynamics and density functional theory calculations on water-soluble Mo-based catalysts for proton reduction, in order to study the energetics of protonation reactions in complexes where the incipient proton binds a catalytically active ligand (i.e., an oxide or a disulphide). We considered complexes either soaked in water or in a vacuum, and featuring N-based ancillary ligands of different bulkiness (i.e. cages constituted either by pyridine or isoquinoline moieties). Our results show that the energetics of protonation events can be affected by ancillary ligand bulkiness even when the metal center does not play the role of the H⁺ acceptor. In vacuo, protonation at the O or S atom in the α position relative to the metal in complexes featuring the bulky isoquinoline-based ligand is more favored by around 10 kcal mol^-1 when compared to the case of the pyridine-based counterparts, a difference that is almost zero when the same reactions occur in water. Such an outcome is rationalized in light of the different electrostatic properties of complexes bearing ancillary ligands of different sizes. The overall picture from theory indicates that such effects of ligand bulkiness can be relevant for the design of green chemistry catalysts that undergo protonation steps in water solutions.

Evaluation of docking procedures reliability in affitins-partners interactions

Affitins constitute a class of small proteins belonging to Sul7d family, which, in microorganisms such as Sulfolobus acidocaldarius, bind DNA preventing its denaturation. Thanks to their stability and small size (60–66 residues in length) they have been considered as ideal candidates for engineering and have been used for more than 10 years now, for different applications. The individuation of a mutant able to recognize a specific target does not imply the knowledge of the binding geometry between the two proteins. However, its identification is of undoubted importance but not always experimentally accessible. For this reason, computational approaches such as protein-protein docking can be helpful for an initial structural characterization of the complex. This method, which produces tens of putative binding geometries ordered according to a binding score, needs to be followed by a further reranking procedure for finding the most plausible one. In the present paper, we use the server ClusPro for generating docking models of affitins with different protein partners whose experimental structures are available in the Protein Data Bank. Then, we apply two protocols for reranking the docking models. The first one investigates their stability by means of Molecular Dynamics simulations; the second one, instead, compares the docking models with the interacting residues predicted by the Matrix of Local Coupling Energies method. Results show that the more efficient way to deal with the reranking problem is to consider the information given by the two protocols together, i.e. employing a consensus approach.

Partition of the Reactive Species of the Suzuki-Miyaura Reaction between Aqueous and Micellar Environments

The Suzuki-Miyaura reaction between the aryl halide (1) and the phenyl boronic acid (2), in the presence of the palladium(0) complex (3) as catalyst, gives the cross-coupling product (4) in quantitative yield when performed in basic aqueous solution of the nonionic surfactant Kolliphor-EL (K-EL). The partition between the aqueous and micellar environments of the species of this reaction has been investigated by means of Molecular Dynamics (MD) simulations. Starting from the K-EL molecules dispersed in water, a micelle model has been generated by MD simulations, adopting the 2016H66 force field. Reagent and product species have been described with the same force field, once the reliability of this force field has been tested comparing the n-octanol/water partition free energies calculated from the MD and Free Energy Perturbation (FEP) method with those obtained from the quantum-mechanical SMD method. The potential of mean force for the transfer process between water and the micellar phase of the different species has been calculated by the MD simulations and the Umbrella Sampling (US) method. The overall picture that emerges from these results confirms that the molecular species involved in this reaction prefers the micellar environment and concentrates in different but close zones of the micelle. This supports the experimental evidence that the use of suitable surfactant agents promotes reactivity, allowing micelles to behave as nanoreactors in which reactive species are solubilized and enhance their local concentration.

Chemical diversity, medicinal potentialities, biosynthesis, and pharmacokinetics of anthraquinones and their congeners derived from marine fungi: a comprehensive update

Marine fungi receive excessive attention as prolific producers of structurally unique secondary metabolites, offering promising potential as substitutes or conjugates for current therapeutics, whereas existing research has only scratched the surface in terms of secondary metabolite diversity and potential industrial applications as only a small share of bioactive natural products have been identified from marine-derived fungi thus far. Anthraquinones derived from filamentous fungi are a distinct large group of polyketides containing compounds which feature a common 9,10-dioxoanthracene core, while their derivatives are generated through enzymatic reactions such as methylation, oxidation, or dimerization to produce a large variety of anthraquinone derivatives. A considerable number of reported anthraquinones and their derivatives have shown significant biological activities as well as highly economical, commercial, and biomedical potentialities such as anticancer, antimicrobial, antioxidant, and anti-inflammatory activities. Accordingly, and in this context, this review comprehensively covers the state-of-art over 20 years of about 208 structurally diverse anthraquinones and their derivatives isolated from different species of marine-derived fungal genera along with their reported bioactivity wherever applicable. Also, in this manuscript, we will present in brief recent insights centred on their experimentally proved biosynthetic routes. Moreover, all reported compounds were extensively investigated for their in-silico drug-likeness and pharmacokinetics properties which intriguingly highlighted a list of 20 anthraquinone-containing compounds that could be considered as potential drug lead scaffolds.

Copper starvation induces antimicrobial isocyanide integrated into two distinct biosynthetic pathways in fungi

The genomes of many filamentous fungi, such as Aspergillus spp., include diverse biosynthetic gene clusters of unknown function. We previously showed that low copper levels upregulate a gene cluster that includes crmA, encoding a putative isocyanide synthase. Here we show, using untargeted comparative metabolomics, that CrmA generates a valine-derived isocyanide that contributes to two distinct biosynthetic pathways under copper-limiting conditions. Reaction of the isocyanide with an ergot alkaloid precursor results in carbon-carbon bond formation analogous to Strecker amino-acid synthesis, producing a group of alkaloids we term fumivalines. In addition, valine isocyanide contributes to biosynthesis of a family of acylated sugar alcohols, the fumicicolins, which are related to brassicicolin A, a known isocyanide from Alternaria brassicicola. CrmA homologs are found in a wide range of pathogenic and non-pathogenic fungi, some of which produce fumicicolin and fumivaline. Extracts from A. fumigatus wild type (but not crmA-deleted strains), grown under copper starvation, inhibit growth of diverse bacteria and fungi, and synthetic valine isocyanide shows antibacterial activity. CrmA thus contributes to two biosynthetic pathways downstream of trace-metal sensing.

P23 TIMING OF EJECTION FRACTION REASSESSMENT AFTER SACUBITRIL–VALSARTAN INITIATION FOR INDICATION TO DEFIBRILLATOR IMPLANTATION. A SINGLE CENTER EXPERIENCE

Background

Sacubitril/Valsartan (SV) has been validated for heart failure (HF) with reduced ejection fraction (EF) treatment. SV is effective on hard end–points as well as symptoms and heart remodeling. Present guidelines reccomend at least 3 month of optimized medical therapy (OMT). However, the best timing of EF assessment after SV initiation in order to proceed with defibrillator (ICD) implantation, is still unknown.

Purpose

Evaluate timing of improvement of EF after SV initiation in patients (pts) with systolic HF, candidates to primary prevention ICD implantation.

Methods

From 1 of february 2018, we evaluated retrospectively clinical and echocardiographic data of all consecutive pts with EF &lt; 35% treated with SV and candidates to primary prevention ICD implantation. We evaluated clinical and echo follow up (Fup). Results have been analyzed with paired T–test.

Results

The study involved 95 pts (mean age 67±10 years, 70% male, ischaemic etiology 48%). Mean EF at enrollment was 30 ± 5% (ED vol 90 ±23 ml/m2; ES vol 62 ± 19 ml/m2, severe MR 23%) and NYHA III–IV 50%. In 58% pts reached the target dose of SV (97/103 mg bid). After a mean Fup of 6 months, mean EF of the study population increased to 37±7% (ED vol 80±19 ml/m2, ES vol 51±17 ml/m2, severe MR 5%, p &lt; 0.001), and NYHA III–IV decreased to 8% (p = 0.01). Interestingly, thirty–one pts (32%) had their first Fup within 3 months and showed already an improvement [meanEF 28±5% to 35±6%; ΔEF 7±6%; NYHA III–IV 10 %]. Moreover, 49 pts (51%) had last Fup echo after 1 year (mean 13±6 months) and showed a further EF improvement (meanEF 41±8%; ΔEF 12±9%; p &lt; 0.001).Sixteen pt (16%) underwent ICD (62%) or CRT–D (38%) implantation after 3±2 months of treatment and excluded from further FUP analysis. More favorable effects of treatment with SV were more evident in patient with non–ischaemic etiology of heart failure.

Conclusions

After SV initiation in systolic HF, favourable heart remodeling is clearly evident at 6 months FUP, but could be already observed after 3 months . These findings need to be validated from larger trials but suggest that the best timing of EF reassessment to decide for primary prevention ICD is likely between 3 and 6 months after SV initiation. However decision must be taken following close and individualized FUP for every patient, based on clinical characteristics and response to OMT.

Bypassing the statistical limit of singlet generation in sensitized upconversion using fluorinated conjugated systems

The photon upconversion based on triplet-triplet annihilation (TTA) is a mechanism that converts the absorbed low-energy electromagnetic radiation into higher energy photons also at extremely low excitation intensities, but its use in actual technologies is still hindered by the limited availability of efficient annihilator moieties. We present here the results obtained by the synthesis and application of two new fluorinated chromophores based on phenazine and acridine structures, respectively. Both compounds show upconverted emission demonstrating their ability as TTA annihilator. More interesting, the acridine-based chromophore shows an excellent TTA yield that overcomes the one of some of best model systems. By correlating the experimental data and the quantum mechanical modeling of the investigated compound, we propose an alternative efficient pathway for the generation of the upconverted emissive states involving the peculiar high-energy triplet levels of the dye, thus suggesting a new development strategy for TTA annihilators based on the fine tuning of their high-energy excited states properties.

Can water act as a nucleophile in CO oxidation catalysed by Mo/Cu CO-dehydrogenase? Answers from theory

The aerobic CO dehydrogenase from Oligotropha carboxidovorans is an environmentally crucial bacterial enzyme for maintenance of subtoxic concentration of CO in the lower atmosphere, as it allows for the oxidation of CO to CO₂ which takes place at its Mo−Cu heterobimetallic active site. Despite extensive experimental and theoretical efforts, significant uncertainties still concern the reaction mechanism for the CO oxidation. In this work, we used the hybrid quantum mechanical/molecular mechanical approach to evaluate whether a water molecule present in the active site might act as a nucleophile upon formation of the new C−O bond, a hypothesis recently suggested in the literature. Our study shows that activation of H₂O can be favoured by the presence of the Mo=O_eq group. However, overall our results suggest that mechanisms other than the nucleophilic attack by Mo=O_eq to the activated carbon of the CO substrate are not likely to constitute reactive channels for the oxidation of CO by the enzyme.

Artificial Intelligence Models Do Not Ground Negation, Humans Do. GuessWhat?! Dialogues as a Case Study

Negation is widely present in human communication, yet it is largely neglected in the research on conversational agents based on neural network architectures. Cognitive studies show that a supportive visual context makes the processing of negation easier. We take GuessWhat?!, a referential visually grounded guessing game, as test-bed and evaluate to which extent guessers based on pre-trained language models profit from negatively answered polar questions. Moreover, to get a better grasp of models' results, we select a controlled sample of games and run a crowdsourcing experiment with subjects. We evaluate models and humans against the same settings and use the comparison to better interpret the models' results. We show that while humans profit from negatively answered questions to solve the task, models struggle in grounding negation, and some of them barely use it; however, when the language signal is poorly informative, visual features help encoding the negative information. Finally, the experiments with human subjects put us in the position of comparing humans and models' predictions and get a grasp about which models make errors that are more human-like and as such more plausible.

The impact of modern radiotherapy on long-term cardiac sequelae in breast cancer survivor: a focus on deep inspiration breath-hold (DIBH) technique

INTRODUCTION

One of the most feared side effects of radiotherapy (RT) in the setting of breast cancer (BC) patients is cardiac toxicity. This side effect can jeopardize the quality of life (QoL) of long-term survivors. The impact of modern techniques of RT such as deep inspiration breath hold (DIBH) have dramatically changed this setting. We report and discuss the results of the literature overview of this paper.

MATERIALS AND METHODS

Literature references were obtained with a PubMed query, hand searching, and clinicaltrials.gov.

RESULTS

We reported and discussed the toxicity of RT and the improvements due to the modern techniques in the setting of BC patients.

CONCLUSIONS

BC patients often have a long life expectancy, thus the RT should aim at limiting toxicities and at the same time maintaining the same high cure rates. Further studies are needed to evaluate the risk-benefit ratio to identify patients at higher risk and to tailor the treatment choices.

Core Steps to the Azaphilone Family of Fungal Natural Products

Azaphilones are a family of polyketide-based fungal natural products that exhibit interesting and useful bioactivities. This minireview explores the literature on various characterised azaphilone biosynthetic pathways, which allows for a proposed consensus scheme for the production of the core azaphilone structure, as well as identifying early diversification steps during azaphilone biosynthesis. A consensus understanding of the core enzymatic steps towards a particular family of fungal natural products can aid in genome-mining experiments. Genome mining for novel fungal natural products is a powerful technique for both exploring chemical space and providing new insights into fungal natural product pathways.

Timing of ejection fraction reassessment after sacubitril-valsartan initiation for indication to defibrillator implantation. A single center experience

Background

Sacubitril/Valsartan (SV) has recently been validated in the therapy of heart failure (HF) with reduced ejection fraction (EF). SV is effective on symptoms and heart remodeling. At the moment the best timing to EF assessment after SV initiation in order to proceed with defibrillator (ICD) implantation, it's unknown.

Purpose

Evaluate the timing of improvement of EF after SV initiation in patients (pts) with systolic HF, candidates to primary prevention ICD implantation.

Methods

We enrolled all consecutive pts candidates to primary prevention ICD implantation that underwent SV initiation from February 2018. We evaluated clinical and echo follow up (Fup). Results have been analyzed with paired T-test).

Results

The study involved 61 pts (mean age 67±10 years, 71% male, ischemic cardiopathy 44%, mean time from diagnosis 31 months) with mean EF at enrollment 30±5% (ED vol 94 ml/m2, ES vol 64 ml/m2, severe MR 21%) and mean NYHA 3±0.6. After a mean Fup of 6 months mean EF increased to 37±7% (ED vol 80 ml/m2, ES vol 51 ml/m2, severe MR 8%, p&lt;0.004), NYHA decreased to 2±0.6 (p&lt;0.04). In 69% pts SV dosage reached 97/103 mg bid. 28 pts (45%) had first Fup at 3 months and showed already mean EF 34±6% and mean NYHA 1.6±0.6 (p&lt;0.04). 26 pts (43%) had last Fup echo after 1 year (mean 17±10 months) and showed further EF little improvement (38.3±8%, p 0.05).

Conclusions

After SV initiation in systolic HF, heart remodeling is already evident at 3 months Fup and better appreciable at 6 months Fup. Little non significant further EF improvement could be seen later. In our study best timing to decide for primary prevention ICD is likely between 3 and 6 months after SV initiation.

Funding Acknowledgement

Type of funding sources: None. Figure 1

BLITZ-HF study: a nationwide initiative to assess and improve guidelines recommendations adherence in cardiology centers managing patients with acute and chronic heart failure

Background

Physicians adherence to heart failure (HF) guidelines is generally sub-optimal with consequent negative prognostic implications. Strategies to improve adherence to guideline recommendations are strongly needed.

Aims

To assess and improve adherence of Italian cardiology sites to guidelines recommendations on performance indicators in patients with acute (AHF) and chronic heart failure (CHF).

Methods

BLITZ-HF was a prospective study based on a web based recording system used during two enrollment periods (phase 1 and 3), interspersed by face-to-face macro-regional benchmark analysis and educational meetings (phase 2). Both management (creatinine and echocardiographic evaluations or discharge follow-up planning) and treatment (according to ejection fraction categories, focusing on guidelines directed medical treatments - GDMTs) performance indicators were considered for patients in both settings.

Results

Overall, 7218 patients with acute and chronic HF were enrolled at 106 sites. During the enrollment phases, 3920 and 3298 patients were included respectively, 84% with CHF and 16% with AHF in phase 1, 74% with CHF and 26% with AHF in phase 3. In Figure 1 we report adherence to management and treatment indicators in the two enrollment phases. Among AHF patients improvement was obtained in two of seven indicators. A significant rise in echocardiographic evaluation was observed, while discharge schedule of a cardiology ambulatory evaluation within four weeks was overall poor (less than 50%) and did not improve in the 3 phase. Overall GDMTs prescription rate in HFrEF was good and we observed a nominal increase in betablockers prescription rate in Phase 3. Among CHF patients with HFpEF and HFmrEF we observed a performance increase in two of three indicators: creatinine end echocardiographic evaluations, while oral anticoagulation in atrial fibrillation remained stably high. Performance measures in CHF HFrEF patients improved in six of nine indicators although significantly only in two. Prescription rate of GDMTs was good already in phase 1 and a significant increase in ACE-I/ARB or ARNI prescription was reported, with a nominal increase in the use of one of these three drugs in combination with MRAs and a BB.

Conclusions

A structured multifaceted educational intervention can improve adherence to HF guidelines on several indicators in a context of an already elevated level of adherence to guideline recommendations. Extension of this approach to other non-cardiology health professional settings, in which patients with HF are generally managed, should be considered.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): The study was funded by Heart Care Foundation with a partial unrestricted support from Abbott, Daiichi Sankyo, Medtronic, Servier, Vifor.

Practical management of epidermolysis bullosa: consensus clinical position statement from the European Reference Network for Rare Skin Diseases

Inherited epidermolysis bullosa (EB) comprises rare disorders that manifest with fragility and blistering of the skin and mucous membranes, with variable clinical severity. Management of EB is challenging due to disease rarity and complexity, the wide range of extracutaneous manifestations and a profound impact on daily life for the patient and family members. Although reference centres providing multidisciplinary care for EB exist in each European country, it is common for healthcare professionals that are not specialized in this rare disorder to treat EB patients. Here, experts of the European Reference Network for Rare and Undiagnosed Skin Diseases (ERN-Skin, https://ern-skin.eu) propose practical recommendations for the diagnosis and management of the commonest clinical issues, skin blisters and wounds, oral manifestations, pain and itch.

The sexual spore pigment asperthecin is required for normal ascospore production and protection from UV light in Aspergillus nidulans

Many fungi develop both asexual and sexual spores that serve as propagules for dissemination and/or recombination of genetic traits. Asexual spores are often heavily pigmented and this pigmentation provides protection from UV light. However, little is known about any purpose pigmentation may serve for sexual spores. The model Ascomycete Aspergillus nidulans produces both green pigmented asexual spores (conidia) and red pigmented sexual spores (ascospores). Here we find that the previously characterized red pigment, asperthecin, is the A. nidulans ascospore pigment. The asperthecin biosynthetic gene cluster is composed of three genes, aptA, aptB, and aptC where deletion of either aptA (encoding a polyketide synthase) or aptB (encoding a thioesterase) yields small, mishappen hyaline ascospores while deletion of aptC (encoding a monooxygenase) yields morphologically normal but purple ascospores. ∆aptA and ∆aptB but not ∆aptC or WT ascospores are extremely sensitive to UV light. We find that two historical ascospore color mutants, clA6 and clB1, possess mutations in aptA and aptB sequences respectively.

QM/MM study of the binding of H2 to MoCu CO dehydrogenase: development and applications of improved H2 van der Waals parameters

The MoCu CO dehydrogenase enzyme not only transforms CO into CO₂ but it can also oxidise H₂. Even if its hydrogenase activity has been known for decades, a debate is ongoing on the most plausible mode for the binding of H₂ to the enzyme active site and the hydrogen oxidation mechanism. In the present work, we provide a new perspective on the MoCu-CODH hydrogenase activity by improving the in silico description of the enzyme. Energy refinement—by means of the BigQM approach—was performed on the intermediates involved in the dihydrogen oxidation catalysis reported in our previously published work (Rovaletti, et al. “Theoretical Insights into the Aerobic Hydrogenase Activity of Molybdenum–Copper CO Dehydrogenase.” Inorganics 7 (2019) 135). A suboptimal description of the H₂–HN(backbone) interaction was observed when the van der Waals parameters described in previous literature for H₂ were employed. Therefore, a new set of van der Waals parameters is developed here in order to better describe the hydrogen–backbone interaction. They give rise to improved binding modes of H₂ in the active site of MoCu CO dehydrogenase. Implications of the resulting outcomes for a better understanding of hydrogen oxidation catalysis mechanisms are proposed and discussed.

Triiron clusters derived from dinuclear complexes related to the active site of [Fe–Fe] hydrogenases: steric effect of the dithiolate bridge on redox properties, a DFT analysis

CV and DFT calculations reveal that electrochemical behaviours of triiron clusters [Fe₃(CO)₅(κ₂-dppe)(μ-pdt^R2)(μ-pdt)] depend on the nature of the dithiolate bridge.

First-Principles Calculations on Ni,Fe-Containing Carbon Monoxide Dehydrogenases Reveal Key Stereoelectronic Features for Binding and Release of CO2 to/from the C-Cluster

In view of the depletion of fossil fuel reserves and climatic effects of greenhouse gas emissions, Ni,Fe-containing carbon monoxide dehydrogenase (Ni-CODH) enzymes have attracted increasing interest in recent years for their capability to selectively catalyze the reversible reduction of CO₂ to CO (CO₂ + 2H⁺ + 2e^– CO + H₂O). The possibility of converting the greenhouse gas CO₂ into useful materials that can be used as synthetic building blocks or, remarkably, as carbon fuels makes Ni-CODH a very promising target for reverse-engineering studies. In this context, in order to provide insights into the chemical principles underlying the biological catalysis of CO₂ activation and reduction, quantum mechanics calculations have been carried out in the framework of density functional theory (DFT) on different-sized models of the Ni-CODH active site. With the aim of uncovering which stereoelectronic properties of the active site (known as the C-cluster) are crucial for the efficient binding and release of CO₂, different coordination modes of CO₂ to different forms and redox states of the C-cluster have been investigated. The results obtained from this study highlight the key role of the protein environment in tuning the reactivity and the geometry of the C-cluster. In particular, the protonation state of His93 is found to be crucial for promoting the binding or the dissociation of CO₂. The oxidation state of the C-cluster is also shown to be critical. CO₂ binds to C_red2 according to a dissociative mechanism (i.e., CO₂ binds to the C-cluster after the release of possible ligands from Fe_u) when His93 is doubly protonated. CO₂ can also bind noncatalytically to C_red1 according to an associative mechanism (i.e., CO₂ binding is preceded by the binding of H₂O to Fe_u). Conversely, CO₂ dissociates when His93 is singly protonated and the C-cluster is oxidized at least to the C_int redox state.

Density functional theory was used to investigate Ni,Fe-containing carbon monoxide dehydrogenase enzymes. Different coordination modes of the substrate CO₂ to several forms and redox states of the C-cluster—the enzyme active site—were considered. The obtained results highlight the key role of the protein environment in tuning the reactivity and the geometry of the C-cluster. This helps to uncover which stereoelectronic properties of the active site are crucial for the efficient binding and release of CO₂.

Rational Design of Fe2 (μ-PR2 )2 (L)6 Coordination Compounds Featuring Tailored Potential Inversion

It was recently discovered that some redox proteins can thermodynamically and spatially split two incoming electrons towards different pathways, resulting in the one-electron reduction of two different substrates, featuring reduction potential respectively higher and lower than the parent reductant. This energy conversion process, referred to as electron bifurcation, is relevant not only from a biochemical perspective, but also for the ground-breaking applications that electron-bifurcating molecular devices could have in the field of energy conversion. Natural electron-bifurcating systems contain a two-electron redox centre featuring potential inversion (PI), i. e. with second reduction easier than the first. With the aim of revealing key factors to tailor the span between first and second redox potentials, we performed a systematic density functional study of a 26-molecule set of models with the general formula Fe₂ (μ-PR₂ )₂ (L)₆ . It turned out that specific features such as i) a Fe-Fe antibonding character of the LUMO, ii) presence of electron-donor groups and iii) low steric congestion in the Fe's coordination sphere, are key ingredients for PI. In particular, the synergic effects of i)-iii) can lead to a span between first and second redox potentials larger than 700 mV. More generally, the "molecular recipes" herein described are expected to inspire the synthesis of Fe₂ P₂ systems with tailored PI, of primary relevance to the design of electron-bifurcating molecular devices.

Uncovering biosynthetic relationships between antifungal nonadrides and octadrides

Maleidrides are a class of bioactive secondary metabolites unique to filamentous fungi, which contain one or more maleic anhydrides fused to a 7-, 8- or 9- membered carbocycle (named heptadrides, octadrides and nonadrides respectively). Herein structural and biosynthetic studies on the antifungal octadride, zopfiellin, and nonadrides scytalidin, deoxyscytalidin and castaneiolide are described. A combination of genome sequencing, bioinformatic analyses, gene disruptions, biotransformations, isotopic feeding studies, NMR and X-ray crystallography revealed that they share a common biosynthetic pathway, diverging only after the nonadride deoxyscytalidin. 5-Hydroxylation of deoxyscytalidin occurs prior to ring contraction in the zopfiellin pathway of Diffractella curvata. In Scytalidium album, 6-hydroxylation - confirmed as being catalysed by the α-ketoglutarate dependent oxidoreductase ScyL2 - converts deoxyscytalidin to scytalidin, in the final step in the scytalidin pathway. Feeding scytalidin to a zopfiellin PKS knockout strain led to the production of the nonadride castaneiolide and two novel ring-open maleidrides.

Chemical warfare between fungus-growing ants and their pathogens

Fungus-growing attine ants are under constant threat from fungal pathogens such as the specialized mycoparasite Escovopsis, which uses combined physical and chemical attack strategies to prey on the fungal gardens of the ants. In defence, some species assemble protective microbiomes on their exoskeletons that contain antimicrobial-producing Actinobacteria. Underlying this network of mutualistic and antagonistic interactions are an array of chemical signals. Escovopsis weberi produces the shearinine terpene-indole alkaloids, which affect ant behaviour, diketopiperazines to combat defensive bacteria, and other small molecules that inhibit the fungal cultivar. Pseudonocardia and Streptomyces mutualist bacteria produce depsipeptide and polyene macrolide antifungals active against Escovopsis spp. The ant nest metabolome is further complicated by competition between defensive bacteria, which produce antibacterials active against even closely related species.

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Specialist fungal pathogens attack the nests of fungus-growing ants.

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Ants form mutualistic relationships with defensive actinomycete bacteria.

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Specialised metabolites underpin these mutualistic and antagonistic interactions.

Dynamical Behavior and Conformational Selection Mechanism of the Intrinsically Disordered Sic1 Kinase-Inhibitor Domain

Intrinsically Disordered Peptides and Proteins (IDPs) in solution can span a broad range of conformations that often are hard to characterize by both experimental and computational methods. However, obtaining a significant representation of the conformational space is important to understand mechanisms underlying protein functions such as partner recognition. In this work, we investigated the behavior of the Sic1 Kinase-Inhibitor Domain (KID) in solution by Molecular Dynamics (MD) simulations. Our results point out that application of common descriptors of molecular shape such as Solvent Accessible Surface (SAS) area can lead to misleading outcomes. Instead, more appropriate molecular descriptors can be used to define 3D structures. In particular, we exploited Weighted Holistic Invariant Molecular (WHIM) descriptors to get a coarse-grained but accurate definition of the variegated Sic1 KID conformational ensemble. We found that Sic1 is able to form a variable amount of folded structures even in absence of partners. Among them, there were some conformations very close to the structure that Sic1 is supposed to assume in the binding with its physiological complexes. Therefore, our results support the hypothesis that this protein relies on the conformational selection mechanism to recognize the correct molecular partners.