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A one-dimensional model of the cooling process occurring in a hybrid-rocket nozzle working with cryogenic oxygen flowing through helical channels is addressed in this work. Although the regenerative cooling system in rocket engines involves further complexity, it is here investigated as an option for the suppression of graphite-nozzle erosion in hybrid rockets. The model is based on the solution of the conservation equations of mass, momentum, and energy of the coolant. The Modified Benedict-Webb-Rubin equation of state was used for its accuracy in both the fluid phases of oxygen. The conservation equations for the coolant flow are coupled with a one-dimensional heat transfer model for the evaluation of the nozzle wall temperature at both the cold and hot sides, which has allowed assessing the developed model prediction capabilities by means of the data collected from three engine hot firings. Thus, parametric analyses were carried out to show the effect of the number of helical channels and evaluate the performance improvement obtained in supercritical conditions. • Study of a hybrid rocket nozzle cooling system based on cryogenic oxygen flowing through helical cooling channels. • 1D modelling of the nozzle cooling with cryogenic oxygen flowing through helical channels. • Validation on firing tests by transient simulations. • Effect of the number of channels in a helical configuration. [ABSTRACT FROM AUTHOR]

Starting from the data measured in several static firings of two laboratory-scale hybrid rocket engines of different sizes burning gaseous oxygen with either a liquefying fuel or a pyrolyzing polymer, a mechanism for the combustion instability observed only with liquefying fuel is suggested. With the latter type of fuels, regression rate is increased for the formation of an unstable liquid layer on the grain surface, for which liquid fuel structures are entrained into the gas stream and burn, upon vaporization and mixing, far from the surface. Based on this circumstance, the hypothesis of a time delay to burn, with the resulting effect of triggering longitudinal acoustic modes of the system, is formulated. A simplified analytical acoustic model of a series of interconnected ducts with different cross sections and gas properties is preliminarily addressed, which allowed demonstrating the acoustic nature of the main pressure oscillation peaks measured in three firing tests along with the influence of the oxygen-feeding line on the system acoustics. Finally, by leveraging an existing acoustic model of the hybrid rocket combustion chamber including the effects of cross-sectional discontinuities and distributed fuel mass addition and combustion, the linear stability of the system is analyzed, whose results are apt to reproduce the experimental findings. [ABSTRACT FROM AUTHOR]

This article discusses the use of low-dose oral minoxidil (LDOM) as a treatment for traction alopecia (TA) in women. TA is a condition that primarily affects women of African descent and is caused by prolonged tension on the hair follicles due to certain hair grooming practices. The study presents a case series of four patients who experienced significant hair regrowth after using oral minoxidil. The treatment was found to be effective and safe, with improvements in hair thickness and volume observed after just three months of therapy. The article suggests that oral minoxidil may be a viable option for treating TA in both the early and late stages. [Extracted from the article]

In this work, we describe the preparation and characterization of supramolecular ionic liquid gels based on binary mixtures of biopolymers, comprising chitosan, chitin, cellulose and lignin. The gels were obtained in ionic liquids differing in the cation or the anion, with no need for a cross-linking agent or acid treatment. The materials obtained were characterized for the minimum gelation concentration, porosity, swelling and rheological properties, finding a prominent influence of the nature of the ionic liquid anion. Then, we investigated the ability of the gels to scavenge free radicals, finding that the gels exhibit a higher antioxidant ability than their individual components. Moreover, our gels showed a bactericidal activity toward Gram-positive and Gram-negative bacterial strains like Streptomyces coelicolor and Escherichia coli, respectively. The kinetics of bacterial cell viability showed that the gel based on a chitosan : chitin mixture in the IL [bmim][Cl] was the fastest acting against E. coli, with a practically total killing of bacterial cells within 30 min. Once again, a major influence of the ionic liquid anion was detected. Finally, we found an inverse relationship between the antioxidant and antimicrobial activities of our gels. [ABSTRACT FROM AUTHOR]

To explore the feasibility and image quality of ultra-low volume contrast-saline mixture injection with dual-flow injection technique in a computed tomography angiography (CTA) protocol in patients scheduled for transcatheter aortic valve implantation (TAVI). Forty (40) TAVI candidates underwent investigation with CTA using a third-generation dual-source CT scanner between September and November 2020. Different volumes of a monophasic contrast-saline mixture at an 80:20 ratio were administered at an infusion rate of 3 mL/s in 20 patients (group A). The injected volume was based on patient body mass index (BMI): 50 mL if BMI <29 kg/m2 and 63 mL if BMI >29 kg/m2. The other 20 patients (group B)—the control cases—received a total of 65 mL of contrast medium (CM), in multiphasic injections at different flow rates, followed by 10 mL of saline. The images that were obtained were prospectively evaluated for image quality, vessel attenuation (HU), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and estimated radiation dose. Image quality of the aortic root and ilio-femoral vessels was diagnostic in all patients. Vascular attenuation was >200 HU and CNR >3 at any vessel level. Data from this study suggest that a monophasic ultra-low volume contrast-saline mixture injection with a dual-flow technique can provide clear visualisation of the aortic root and ilio-femoral vessels in pre-TAVI CTA, which is comparable with a standard multiphasic volume injection protocol. [ABSTRACT FROM AUTHOR]

Understanding the physical mechanism of ground deformation at a volcano supports the use of deformation data as a monitoring tool. An inverse correlation was observed between eruption frequency and ground deformation of Sakurajima volcano from November 2018 to April 2021. Over the same period, the mass density of magma in the conduit was monitored via muography. Mass density increased during inflation, when eruption frequency was low, and decreased during deflation, when eruption frequency was high. Periods of low eruption frequency are associated with the formation of a dense plug in the conduit, which we infer caused the inflation of the edifice by trapping pressurized magmatic gas. Conversely, periods of high eruption frequency are associated with the absence of the plug, which we infer allows gas to escape, leading to deflation. Muography thus reveals the in‐conduit physical mechanism for the observed correlation, with implications for interpretation of deformation at other volcanoes. Plain Language Summary: The ground surface of a volcano often deforms before an eruption. Remote sensing of ground movements could be a valuable tool for eruption forecasting if the physical causes of ground deformation were known. We have used naturally occurring cosmic muons to image the changes in mass density over time in the upper plumbing system of Sakurajima Volcano (Japan) and compared this with ground surface motions and eruption activity. We found that the mass density increased during dormant periods, when the ground surface of the volcano was high, and the mass density decreased during periods of frequent eruption, when the ground surface was low. Muon imaging helped to reveal the hidden volcanic processes: the volcano plugged with dense magma during dormant periods allowing pressure in the conduit to build up, resulting in the uplift of the volcano's surface. During periods of eruption, the plug was destroyed and replaced with fresh, lower‐density magma, releasing pressure and causing the volcano's surface to move downwards. Key Points: An inverse correlation was observed between eruption frequency and ground surface deformation of Sakurajima volcanoBeneath the crater, muon imaging visualized that the mass density increased during ground inflation and decreased during ground deflationPlugging of the conduit with dense, stiff magma during recharge caused inflation during quiescent periods [ABSTRACT FROM AUTHOR]

Nail psoriasis is a chronic nail disorder that commonly affects psoriatic patients causing severe distress despite the limited body surface area. Treatments for nail psoriasis are limited, as nails are often difficult to treat with topical therapies, and among different systemic agents responses are unpredictable. We carried out a prospective study in order to analyze the effectiveness and tolerability of topical cyclosporine hydrogel ointment in nail psoriasis. Three patients, for a total of 44 nails, were treated with topical cyclosporine hydrogel ointment. All nails were evaluated, before starting the treatment, every 28 days and after 12 weeks of therapy, by the same dermatologists, through clinical and onychoscopic evaluations. The patients were also asked to assess on the compliance with product use. Complete response (CR) was observed in 2 of 3 patients; a partial response (PR) was observed in the other patient. Overall, 24 of 44 nails had CR and 20 had a PR. Cyclosporine hydrogel ointment has shown efficacy and safety in the treatment of nail psoriasis. The product has also been shown to be stable in composition, easy to apply and not discomfortable for the patient. [ABSTRACT FROM AUTHOR]

Our work confirms and emphasizes the role of LDOM in achieving good aesthetic relevance with camouflage effect of LPP-affected female patients, with an even higher rate of efficacy. Low-dose oral minoxidil in female patients with lichen planopilaris: Real-life experience Dear Editor, Lichen planopilaris (LPP) is the most frequent form of scarring alopecia, which mainly affects women between 40 and 60 years of age. [Extracted from the article]

Compared with conventional configurations, axial-injection end-burning hybrid rocket motors work with multiport fuel grains, which mainly burn in the axial direction. The consumption rate is controlled by the several flames developed at the end of each port. Although many studies of performance and flame stability have been carried out in the past, a phenomenological model of the axial regression rate was never provided in the past, which is the objective of the current work. The validation of the physical model is performed by a comparative study between firing tests using gaseous oxygen and nitrous oxide. Two experimental campaigns performed by a pressure-controlled combustion chamber are carried out with a single port grain in operative conditions equivalent to the multiport configuration. The axial regression rate was measured by varying the port diameter in a range between 0.5 and 4.6 mm, the mass flow rate between 0.004 and 1.7 g/s, and the chamber pressure between 0.1 and 3.4 MPa. The measured axial regression rate was quantitatively lower with nitrous oxide than oxygen, and the pressure sensitivity exponent decreased from 1.85 to 1.5, respectively. The physical reason has been attributed to the decomposition reaction of nitrous oxide occurring upstream of the flame front. In addition, a general methodology for fuel grain design is given, highlighting the benefits and drawbacks of introducing multiport grains and the effect of the oxidizer choice on the motor geometry. Finally, multiport firing tests were carried out to confirm the evidence observed in the simplified single-port campaigns. [ABSTRACT FROM AUTHOR]

Background: Rugby is team sport and posses both running and contact play features. In a similar way as another sport producing both physical and psychological stress and both aerobic and anaerobic metabolism, rugby induces intensive oxidative stress. This in turn decreases glutathione peroxidase activity. Furthermore, the complete blood count is severely altered by such a condition. Methods: Twelve Italian rugby players were studied. Subjects were studied in the morning of the day of the match and 10 min after the end of match. Erythrocyte glutathione peroxidase activity was analyzed in control and athlete groups pre and post the rugby match both with and without in vitro addition of vitamin C. Using a Coulter counter, we measured red blood cell count, hematocrit, hemoglobin, mean corpuscular volume, white blood cell count, platelets, neutrophils, eosinophils and basophils in 12 male athletes, who gave their informed consensus. Results: GPX data show that its activity is increased by the in vitro addition of Vitamin C (48mM final concentration), both in controls and rugby players. Haematological data describe the major alterations of particulate fraction of blood from rugby players before and after one match and confirm the structural damages in this fraction. GPX activity is worsened by this kind of strenuous exercise and ascorbic acid relieves such damage. Complete blood cell counts of athletes confirm blood cell damages. Conclusion: In summary rugby players show evident cell count derangements and water-soluble reducing Vitamin C relieves oxidative damages of samples from test subjects undergone to full match fatigue [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) vaccines are authorized for use in numerous countries worldwide. Several cutaneous findings are reported after severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) vaccination. Here, we report the case of a patient with a rapid onset of alopecia areata immediately after receiving the second dose of the COVID-19 vaccine. Alopecia areata is a common autoimmune disease leading to non-scarring hair loss. Among the many cutaneous adverse effects reported after the anti-SARS-COV2 vaccination, no episodes of alopecia areata have been described to date. In this paper, we report the first case of alopecia areata after COVID-19 vaccination described in the literature with a revision of cases of alopecia areata reported after other types of vaccination. Although the significance of these skin reactions is not yet known, further studies will certainly clarify whether the development of alopecia areata or other forms of immune-mediated reactions could represent a positive prognostic factor regarding immune protection from SARS-CoV-2. [ABSTRACT FROM AUTHOR]

We report a case of successful percutaneous transhepatic, embolization of an iatrogenic extra-hepatic pseudoaneurysm (PsA) of the right hepatic artery (RHA) under combined fluoroscopic and ultrasonographic guidance. A 73-year-old man underwent percutaneous transhepatic biliary drainage placement in another hospital, complicated by haemobilia and development of a RHA PsA. Endovascular embolization was attempted, resulting in coil embolization of the proper hepatic artery, and persistence of the PsA. At this point, the patient was referred to our hospital. Computed tomography and direct angiography confirmed the iatrogenic extra-hepatic PsA of the RHA, refilled by small collaterals from the accessory left hepatic artery (LHA) and coil occlusion of the proper hepatic artery. Attempted selective catheterization of these vessels was unsuccessful due to the tortuosity and very small caliber of the intra-hepatic collaterals, the latter precluding endovascular treatment of the PsA. Percutaneous trans-hepatic combined fluoroscopic and ultrasound-guided embolization of the PsA was performed with Lipiodol® and cyanoacrylate-based glue (Glubran®2). Real time fluoroscopic images and computed tomography confirmed complete occlusion of the pseudoaneurysm. Surgical repair, although feasible, was considered at high risk. In our patient, we decided to perform a percutaneous trans-hepatic combined fluoroscopic and ultrasound-guided embolization of the PsA using a mix of Lipiodol® and Glubran®2 because of the fast polymerization time of the glue allowing the complete occlusion of the PsA in few seconds, thus eliminating the risk of coil migration, reducing the risk of PsA rupture and avoid a difficult surgical repair. [ABSTRACT FROM AUTHOR]

A low-dose isotretinoin treatment (0.3 mg/kg) was started with progressive regression of the scalp lesions and disappearance of itching with excellent tolerance to therapy without adverse events (Fig. Dear Editor, Eosinophilic pustular folliculitis (EPF) is a rare, very pruritic, benign skin disease that, characterized by itchy papules and sterile pustules on the scalp, is often misdiagnosed and treated extensively with antibiotics with no effect. Histopathological examination of a biopsied erythematous papule of the scalp showed a prominent suppurative folliculitis with blisters and pustules in the deep stratum corneum, focally extending into the sebaceous gland. [Extracted from the article]

The widespread use of antibiotics has resulted in the outbreak and spread of antibiotic-resistant pathogens. Bacterial antibiotic resistance may develop at cellular and community levels. In the latter case, it is based on tolerance which implicates the shift from a free-living form of life (i.e., planktonic) to a sessile multi-stratified community (i.e., biofilm). Metal nanoparticles (MNPs) have been shown to be promising candidates as antimicrobial agents. MNPs are able to interact with and penetrate bacterial biofilms, thus, resulting effective antibiofilm compounds. Another interesting aspect is the possibility of using plants, fungi, yeasts, and bacteria to obtain biogenic MNPs (BMNP). Bacteria are able to grow in presence of many different toxic heavy metal ions thanks to different metal resistance gene clusters that allow a variety of biochemical counters (formation of harmless complexes, efflux, precipitation, reduction, etc.). The formation of BMNPs by bacterial cells could be, in most cases, just a consequence of metal detoxification mechanisms. This review focuses on BMNPs from bacterial origin that may represent a good source of compounds with a broad spectrum of activity against common Gram-positive and Gram-negative pathogens and bacterial biofilms thereof. In particular, the state of art on BMNP synthesis by bacteria is presented and potential applications in the fight against biofilm-associated infections and resistant pathogens are highlighted. In addition, critical aspects on BMNP bacterial synthesis and utilization are commented. Key points • New antimicrobials to fight antibiotic-resistant pathogens are urgently needed. • Biogenic metal nanoparticles can efficiently hit biofilm-forming pathogens. • Metal-nanoparticle composition could confer specific antibiofilm activity. [ABSTRACT FROM AUTHOR]

Organ transplant is considered a life-saving treatment for patients with end-stage diseases. The knowledge of the population and their opinions can influence the willingness of family members and patients to consent to organ and tissue donation. This work aims to evaluate the effectiveness of a webinar intervention as a knowledge translation tool on the Italian population's knowledge and attitudes related to organ and tissue donation. The study used an interventional methodology, analyzing the results of a webinar event lasting 120 minutes organized and managed by 4 experienced professionals in collaboration with the National Association of Donors. Evaluation of customer satisfaction at the end of the webinar was assessed, along with the impact of the event on the participants' perceived knowledge and attitudes. The overall evaluation of the webinar can be considered satisfactory, and the webinar stood as a valid knowledge translation tool. The intervention significantly improved perceived knowledge, attitudes, and propensity to donate. The analysis showed that the difference between brain death and coma was still doubtful. A short webinar course was effective and appreciated by the participants, representing a valid knowledge translation tool and an alternative to in-presence training on specific topics that require the creation of a real "culture of donation." [ABSTRACT FROM AUTHOR]

Folliculotropic Mycosis Fungoides (FMF) is a rare variant of Mycosis Fungoides involving the scalp leading to alopecia. The clinical and trichoscopic features in 18 patients were analyzed and compared with the reports in the literature. Gender, age, disease stage, site of onset were taken into consideration. Clinical and trichoscopic analyses were performed on each patient. From a clinical point of view, Folliculotropic Mycosis Fungoides lesions involving the scalp presented as generalized alopecia (27.8%) or patchy-plaque alopecia (72.2%). Trichoscopic analysis revealed six most frequent features: single hair (83.3%), dotted dilated vessels (77.8%), broken-dystrophic hairs (66.7%), vellus hairs (61.1%), spermatozoa-like pattern vessels (55.6%), and yellow dots (55.6%). Additional identified trichoscopic patterns were dilation of follicular openings, scales-crusts, purpuric dots, short hair with split-end, pigtail hairs, perifollicular hyperkeratosis, milky-white globules, black dots, white dots/lines and absence of follicular dots. These trichoscopic features were further correlated to clinical presentations and stage of the disease. The rarity of the disease is a limitation. The relatively high number of patients allowed to identify several clinical and trichoscopic patterns that could be featured as specific or highly suspicious for FMF in order to consider trichoscopy as a complementary diagnostic approach and improve the differential diagnoses between FMF and other scalp disorders. [ABSTRACT FROM AUTHOR]

• Experimental tests on hybrid rockets using paraffin wax. • Effect of the grain length on the motor performance. • Effect of the grain length on the fuel regression rate. • Effect of the grain length on the combustion stability. An experimental campaign was carried out on a hybrid rocket engine, using gaseous oxygen and paraffin wax-based fuel, to investigate the effect of fuel grain length on motor performance and internal ballistics. The results of the current work offer the reader a comprehensive overview of the pros and cons of reducing the fuel grain length and the difficulties in optimizing combustion efficiency. Steady-state numerical analyses were also performed to support the experimental findings. The motivation for the current work originates from a previous explorative test campaign performed with a 220 mm fuel grain length where only fuel-rich conditions were experienced. A trade-off analysis was carried out by introducing two additional configurations with grain lengths of 130 mm and 70 mm, since the grain length directly affects the mixture ratio and engine performance. Propellant mixing, combustion instability, entrainment, and regression rate are the main topics discussed in the paper. The results show that the reduction of the grain length increases the mixture ratio close to the optimum value, but mixing and combustion instability issues are promoted. No significant effects of the grain length on the regression rate have been found, leading to a discussion on the physics of the mass transfer mechanism of paraffin wax. [ABSTRACT FROM AUTHOR]

This paper presents a computational thermo-fluid-dynamic model of the hybrid rocket internal ballistics, which was developed with the specific aim of predicting the axial position and severity of the increased fuel-consumption spots observed in static engine firings. Numerical simulations of the internal flow field have been carried out on the configuration of the engine previously fired. The novelty of this work consists in providing a simplified methodology to calculate the regression rate measured burning liquid nitrous oxide with high-density polyethylene, which involves a series of additional complexities with respect to the case of pure gaseous oxygen (i.e., a non-decomposing oxidizer). Indeed, the typical non-premixed flame developed in the chamber is preceded by a decomposition reaction of the nitrous oxide, whose simulation implies further numerical cost. For the validation of the model, data retrieved from two firing tests are compared with the numerical results revealing good agreement of both the average regression rate and fuel consumption axial profile. A dedicated study was performed to assess the reliability of the assumptions underlying the model. Results are also compared with those obtained with either pure oxygen or 85 wt.% hydrogen peroxide. Finally, a different prechamber arrangement was suggested to address the issue deriving from excessive fuel regression. [ABSTRACT FROM AUTHOR]

Palmo‐plantar lesions in discoid lupus erythematosus (DLE) can be considered a very distinct rarity, generally refractory to conventional treatments. We present a 47‐year‐old African female patient with a 6‐month clinical history of palm and soles erosions. Clinical examination revealed painful multiple, well defined, erosions with an erythematous and scaly central area and peripherical post‐inflammatory hyperchromic border bilaterally distributed on the palmo‐plantar surfaces. Pterygium inversum unguis involved all nails of both hands. Histological analysis and direct immunofluorescence study confirmed palmo‐plantar DLE. Therapy with mycophenolate mofetil (MMF) was initiated with a progressive clearing of palmo‐plantar lesions and a drastic reduction of pain. Therapy was well tolerated, neither side effects nor altered laboratory investigations were observed. Our case and literature review confirm that MMF may be an effective approach for the management of refractory palmo‐plantar DLE with a safer profile than Azathioprine regarding adverse effects and cutaneous malignancies risk. [ABSTRACT FROM AUTHOR]

This paper deals with the use of a small-scale freeze-dryer, where very few vials are loaded (e.g. 19, each 10 mL, or 7, each 20 mL), for freeze-drying cycle investigation. The system has a metallic ring surrounding the batch of vials, in contact with the external ones, and its temperature is manipulated independently from that of the shelf on the basis of the temperature of the product measured by thermocouples in some vials of the batch. The experimental study was carried out using two sucrose solutions (5% and 10% w/w), aiming to verify the homogeneity of the batch. Both product temperature and the weight loss after 6 h from the onset of the primary drying stage were selected as key parameters. Experiments were carried out according to a 2 N design of experiments, with two values of chamber pressure (60 and 90 mTorr) and two values of shelf temperature (−20 and 0 °C). Satisfactory results may be obtained by selecting a ring temperature 5 °C lower than that of the monitored samples in case of both products investigated. Besides, the system appears to be useful for the estimation of the coefficient of heat transfer to the product (K v) and of the resistance of the dried cake to vapour flux (R p), thus enabling the use of mathematical modelling for process design and optimization. [ABSTRACT FROM AUTHOR]

Background: Increased levels of malondialdehyde (MDA) and 4-hydroxynonenal (HNE) are demonstrated in plasma of uremic patients. A study showed that the comparison of erythrocytes of healthy and diseased patients (obese, hypertensive, and Type 2 diabetics) with age is associated to a disturbed oxidant/antioxidant balance when obesity is associated with hypertension. 4-hydroxytyrosol is shown to significantly protect red blood cells (RBCs) from oxidative damage (4-HNE). In literature, there are partial discussions on the role of lipids and their oxidation products. The products of degradation of membrane proteins are observed as self-consisting products without interrelations with membrane lipids. Objective: The aim of this study is to evaluate the role of polyunsaturated fatty acid (PUFA) metabolites on oxidative damage (4-hydroxy-alkenals) in RBCs of hypertriglyceridemic patients after membrane treatment with 4-hydroxytyrosol. Materials and Methods: The authors optimize the isolation of RBC ghosts and spectrophotometric method to measure free 4-hydroxyalkenals in human RBC membranes and investigated the effect on oxidative damage in human erythrocyte membranes and in vitro 4-hydroxytyrosol treatment to evaluate the membrane lipids reducible by this phenol. Results: Plasma triglyceride levels in patients are clearly higher than in controls. Moreover, total membrane proteins data are similar to previous described. The normalized alkenals levels are significantly enhanced in hyperlipemic patients in comparison to normoglyceridemic controls. After the 4-hydroxytyrosol action, lipid metabolites substantially decrease. The ratio of oxidized lipids (MDA + HNE) and membrane proteins data are similar to previously described ones. Conclusion: According to experimental data, the accumulation of the alkenals in RBC membrane could be produced either by partial PUFA oxidation contained in glycerides and plasma glycerides and by glycerides into plasma membrane recycled RBC. [ABSTRACT FROM AUTHOR]

In the model actinomycete Streptomyces coelicolor A3(2), small open reading frames encoding proteins with unknown functions were identified in several amino acid biosynthetic gene operons, such as SCO2038 (trpX) in the tryptophan trpCXBA locus. In this study, the role of the corresponding protein in tryptophan biosynthesis was investigated by combining phenotypic and molecular analyses. The 2038KO mutant strain was characterized by delayed growth, smaller aerial hyphae and reduced production of spores and actinorhodin antibiotic, with respect to the WT strain. The capability of this mutant to grow on minimal medium was rescued by tryptophan and tryptophan precursor (serine and/or indole) supplementation on minimal medium and by gene complementation, revealing the essential role of this protein, here named TrpM, as modulator of tryptophan biosynthesis. His-tag pull-down and bacterial adenylate cyclase-based two hybrid assays revealed TrpM interaction with a putative leucyl-aminopeptidase (PepA), highly conserved component among various Streptomyces spp. In silico analyses showed that PepA is involved in the metabolism of serine, glycine and cysteine through a network including GlyA, CysK and CysM enzymes. Proteomic experiments suggested a TrpM-dependent regulation of metabolic pathways and cellular processes that includes enzymes such as GlyA, which is required for the biosynthesis of tryptophan precursors and key proteins participating in the morpho-physiological differentiation program. Altogether, these findings reveal that TrpM controls tryptophan biosynthesis at the level of direct precursor availability and, therefore, it is able to exert a crucial effect on the morpho-physiological differentiation program in S. coelicolor A3(2). [ABSTRACT FROM AUTHOR]

Background: The filamentous actinomycete Microbispora ATCC-PTA-5024 produces the lantibiotic NAI-107, which is an antibiotic peptide effective against multidrug-resistant Gram-positive bacteria. In actinomycetes, antibiotic production is often associated with a physiological differentiation program controlled by a complex regulatory and metabolic network that may be elucidated by the integration of genomic, proteomic and bioinformatic tools. Accordingly, an extensive evaluation of the proteomic changes associated with NAI-107 production was performed on Microbispora ATCC-PTA-5024 by combining two-dimensional difference in gel electrophoresis, mass spectrometry and gene ontology approaches. Results: Microbispora ATCC-PTA-5024 cultivations in a complex medium were characterized by stages of biomass accumulation (A) followed by biomass yield decline (D). NAI-107 production started at 90 h (A stage), reached a maximum at 140 h (D stage) and decreased thereafter. To reveal patterns of differentially represented proteins associated with NAI-107 production onset and maintenance, differential proteomic analyses were carried-out on biomass samples collected: i) before (66 h) and during (90 h) NAI-107 production at A stage; ii) during three time-points (117, 140, and 162 h) at D stage characterized by different profiles of NAI-107 yield accumulation (117 and 140 h) and decrement (162 h). Regulatory, metabolic and unknown-function proteins, were identified and functionally clustered, revealing that nutritional signals, regulatory cascades and primary metabolism shift-down trigger the accumulation of protein components involved in nitrogen and phosphate metabolism, cell wall biosynthesis/maturation, lipid metabolism, osmotic stress response, multi-drug resistance, and NAI-107 transport. The stimulating role on physiological differentiation of a TetR-like regulator, originally identified in this study, was confirmed by the construction of an over-expressing strain. Finally, the possible role of cellular response to membrane stability alterations and of multi-drug resistance ABC transporters as additional self-resistance mechanisms toward the lantibiotic was confirmed by proteomic and confocal microscopy experiments on a Microbispora ATCC-PTA-5024 lantibiotic-null producer strain which was exposed to an externally-added amount of NAI-107 during growth. Conclusion: This study provides a net contribution to the elucidation of the regulatory, metabolic and molecular patterns controlling physiological differentiation in Microbispora ATCC-PTA-5024, supporting the relevance of proteomics in revealing protein players of antibiotic biosynthesis in actinomycetes. [ABSTRACT FROM AUTHOR]

This work presents a novel approach for the modelling of the regression rate in hybrid rocket engines loaded with paraffin-fuel. Two different motor thrust classes have been considered in this work to extend the validity of the numerical model on two motor geometries (200 N and 1 kN). The work consists of two parts. Firstly, a unique and general empirical law of the regression rate was found for both the motor configurations, which are governed by different consumption mechanisms due to the injection system. Ballistic reconstruction techniques have been introduced to reproduce the temporal trend of the regression rate during the burning time and to increase the number of experimental tests used for the development of accurate and reliable regression laws. Experimental observations in the larger motor suggest that the entrainment is dominated by mass diffusive transport phenomena, which is modelled here by a Fick-like relation. This model, coupled with a sophisticated gas-surface interaction treatment, allowed the evaluation of the regression rate in each point of the grain surface by computational fluid dynamic simulations. Then, the overall model has been validated on experimental and reconstructed data. Finally, the effect of the motor configuration on the fuel consumption is shown, thus revealing the crucial influence of the separation zone delivered by the axial injection. [ABSTRACT FROM AUTHOR]

Efficacy of switching from adalimumab originator to adalimumab biosimilar in moderate to severe psoriasis patients: A Real-life experience in a tertiary referral centre 30 (41.1%) patients also had a diagnosis of psoriatic arthritis (PsA) before starting the therapy. All patients received at least one conventional treatment before Adalimumab: Methotrexate was the most used (73.9%) conventional treatment before Adalimumab, followed by Ciclosporin (53.4%) and Acitretin (38.3%). [Extracted from the article]

Introduction: The purpose of this study was to evaluate the ability of polyphenols (red wine polyphenols, resveratrol and catechin) on anion permeability for chloride and oxidative damage in human erythrocytes exposed to the water-soluble free radical initiator 2.2'-azobis-2 amidinopropan dihydrochloride (AAPH). Materials and Methods: The reducing agent treatment efficacy was observed by evaluation of anion permeability for chloride, lipid peroxidation and hemolysis in red blood cells (RBCs). Anion permeability for chloride is an indicator of membrane protein damage and is evaluated in RBCs by the specific absorption of methemoglobin (CM) at 590 and 635 nm after treatment of heparinized blood with NaNO2. The measurement of the membrane lipid degradation is obtained by the determination of malondialdehyde. The lipid peroxidation susceptibility is observed after the oxidative stress induced by AAPH. The hemolysis assays are conducted on blood samples in phosphate buffer saline and the morphological changes of erythrocytes are observed by optical microscopy as membrane damage verification parameter. Results: Polyphenol treatment is associated with a significant increase in anion permeability for chloride compared with control and AAPH affected cells. Treatment with polyphenols was associated with a significant reduction in mean ± standard error of the mean membrane lipid peroxidation compared with control and AAPH treatment. Hemolysis data are also obtained in the previously described conditions. RBCs morphology data indeed confirm previous observations. Conclusion: In this study, it is evident that after in vitro oxidative damage of the membrane, red wine polyphenol extracts are as effective reducing agents also on CM indicator of membrane protein damages. Consequently, both red wine and polyphenol extracts both alone and mixed among them efficiently relieve the effects of oxidative stress. [ABSTRACT FROM AUTHOR]

Amycolatopsis balhimycina DSM5908 is an actinomycete producer of balhimycin, an analogue of vancomycin, the antibiotic of 'last resort' against multidrug-resistant Gram-positive pathogens. Most knowledge on glycopeptide biosynthetic pathways comes from studies on A. balhimycina as this strain, among glycopeptide producers, is genetically more amenable. The recent availability of its genome sequence allowed to perform differential proteomic analyses elucidating key metabolic pathways leading to antibiotic production in different growth conditions. To implement proteomic data on A. balhimycina derived from 2- DE approaches and to identify novel components, a combined approach based on protein extraction with different detergents, SDS- PAGE resolution of intact proteins and nano LC- ESI- LIT- MS/ MS analysis of their tryptic digests was carried out. With this procedure, 206 additional new proteins such as very basic, hydrophobic or large species were identified. This analysis revealed either components whose expression was previously only inferred by growth conditions, that is, those involved in glutamate metabolism or in resistance, or proteins that allow the strain to metabolize alkanes. These findings will give additional insight into metabolic pathways that could really contribute to A. balhimycina growth and antibiotic production and metabolic enzymes that could be manipulated to generate a model producing strain to use for synthetic biology. [ABSTRACT FROM AUTHOR]

Background: The aim of this study is to put into evidence and verify the correlation between hemolysis and oxidative damage in subjects who practice spinning. Methods: A total of 12 volunteers, aged 35 ± 5 years were enrolled in the present study (60 min) before and (60 min) after practicing spinning. The measurement of lipid peroxidation products and the hemolysis assays conducted on blood samples of athletic subjects, and also the red blood cell morphological study. Results: The obtained data evidence that there are significant differences at least 60 min after training: in malonyldialdehyde value (0.12 ± 0.05 nmol/ml) and in malonyldialdehyde value with 2,2'-azobis (2-amidinopropane) dihydrochloride (0.22 ± 0.05 nmol/ml), in hemolysis data up to both 80 min (oxidative lysis) and 120 min (2,2' azobis (2-amidinopropane) dihydrochloride lysis) confirmed by microscopical analysis. Conclusion: The described data on red blood cell hemolysis, after exercise-induced oxidative damage (malonyldialdehyde), and the degradation kinetic under action of 2,2'-azobis (2-amidinopropane) dihydrochloride can be described according to a multistage process with multiple contemporaneous equilibria. The final red blood cell echinocytic form could describe the end product of process. Consequently authors hypothesize a relationship between spinning exercise, plasma membrane oxidation and hemolysis susceptibility. [ABSTRACT FROM AUTHOR]

Rutherford-type cables are used in superconducting accelerator magnets. To produce magnetic fields larger than 10 T, brittle superconductors like Nb3Sn are typically used. The original round wire, in the form of a composite of Copper, Niobium and Tin, is assembled into a so-called Rutherford-type cable, which is used to wind the magnet. The magnet is then subjected to a high temperature heat treatment to produce the chemical reactions that make the material superconducting. At this stage the superconductor is brittle and its superconducting properties sensitive to strain. This work describes a 2D finite element model, which simulates the mechanical behavior of Rutherford-type cable before heat treatment. The model was applied to a number of different cable architectures. To validate a critical criterion adopted into the single Nb-Sn wire analysis, the results of the model were compared with those measured experimentally on cable cross sections. [ABSTRACT FROM PUBLISHER]

The alkB gene, encoding an alkane monooxygenase in the actinomycete Gordonia sp. SoCg, was expressed in the non-alkane-degrading actinomycete Streptomyces coelicolor M145. The resulting engineered strain, M145-AH, can grow on n-hexadecane as sole carbon source. To unravel proteins associated with growth on n-alkanes, proteome of M145-AH after 6, 24, and 48 h of incubation in the Bushnell-Haas (BH) mineral medium containing n-hexadecane as sole carbon source (H condition) and in BH without any carbon source (0 condition) were compared using 2D-differential gel electrophoresis. Proteome analysis revealed significant changes only at 48 h, showing 48 differentially abundant proteins identified by mass spectrometry procedures. To asses if these proteins were specifically related to n-hexadecane metabolism, their expression was investigated, comparing H proteome with that of M145-AH incubated in BH with glucose as sole carbon source (G condition). Thus, protein expression profiles at 6, 24, and 48 h under H, 0, and G conditions were combined, revealing that M145-AH regulates in a temporally- and carbon source-dependent manner the expression of proteins involved in regulatory events, central carbon metabolism, respiration, β-oxidation, membrane transport, and amino acid and protein metabolism. Interestingly, 21 % of them, mostly involved in membrane transport and protein metabolism, showed a n-hexadecane-dependent regulation with regulatory proteins such as CRP likely to have a key role in M145-AH n-hexadecane growth. These results, expanding the knowledge on n-alkane utilization in Gram-positive bacteria, reveal genes to be targeted to develop an efficient S. coelicolor M145-AH-based bioremediation system. [ABSTRACT FROM AUTHOR]

Background: A bacterial strain previously isolated from pyrite mine drainage and named BAS-10 was tentatively identified as Klebsiella oxytoca. Unlikely other enterobacteria, BAS-10 is able to grow on Fe(III)-citrate as sole carbon and energy source, yielding acetic acid and CO2 coupled with Fe(III) reduction to Fe(II) and showing unusual physiological characteristics. In fact, under this growth condition, BAS-10 produces an exopolysaccharide (EPS) having a high rhamnose content and metal-binding properties, whose biotechnological applications were proven as very relevant. Results: Further phylogenetic analysis, based on 16S rDNA sequence, definitively confirmed that BAS-10 belongs to K. oxytoca species. In order to rationalize the biochemical peculiarities of this unusual enterobacteriun, combined 2D-Differential Gel Electrophoresis (2D-DIGE) analysis and mass spectrometry procedures were used to investigate its proteomic changes: i) under aerobic or anaerobic cultivation with Fe(III)-citrate as sole carbon source; ii) under anaerobic cultivations using Na(I)-citrate or Fe(III)-citrate as sole carbon source. Combining data from these differential studies peculiar levels of outer membrane proteins, key regulatory factors of carbon and nitrogen metabolism and enzymes involved in TCA cycle and sugar biosynthesis or required for citrate fermentation and stress response during anaerobic growth on Fe(III)-citrate were revealed. The protein differential regulation seems to ensure efficient cell growth coupled with EPS production by adapting metabolic and biochemical processes in order to face iron toxicity and to optimize energy production. Conclusion: Differential proteomics provided insights on the molecular mechanisms necessary for anaeorobic utilization of Fe(III)-citrate in a biotechnologically promising enterobacteriun, also revealing genes that can be targeted for the rational design of high-yielding EPS producer strains. [ABSTRACT FROM AUTHOR]

Actinomycetes are an important source of biologically active compounds, like antibiotics, antitumor agents, and immunosuppressors. Genome sequencing is revealing that this class of microorganisms has larger genomes relative to other bacteria and uses a considerable fraction of its coding capacity (5-10%) for the production of mostly cryptic secondary metabolites. To access actinomycetes biosynthetic capabilities or to improve the pharmacokinetic properties and production yields of these chemically complex compounds, genetic manipulation of the producer strains can be performed. Heterologous expression in amenable hosts can be useful to exploit and to explore the genetic potential of actinomycetes and not cultivable but interesting bacteria. Artificial chromosomes that can be stably integrated into the Streptomyces genome were constructed and demonstrated to be effective for transferring entire biosynthetic gene clusters from intractable actinomycetes into more suitable hosts. In this paper, the construction of several shuttle Escherichia coli-Streptomyces artificial chromosomes is discussed together with old and new strategies applied to improve heterologous production of secondary metabolites. [ABSTRACT FROM AUTHOR]

Actinomycetes are an important source of biologically active compounds, like antibiotics, antitumor agents, and immunosuppressors. Genome sequencing is revealing that this class of microorganisms has larger genomes relative to other bacteria and uses a considerable fraction of its coding capacity (5-10%) for the production of mostly cryptic secondary metabolites. To access actinomycetes biosynthetic capabilities or to improve the pharmacokinetic properties and production yields of these chemically complex compounds, genetic manipulation of the producer strains can be performed. Heterologous expression in amenable hosts can be useful to exploit and to explore the genetic potential of actinomycetes and not cultivable but interesting bacteria. Artificial chromosomes that can be stably integrated into the Streptomyces genome were constructed and demonstrated to be effective for transferring entire biosynthetic gene clusters from intractable actinomycetes into more suitable hosts. In this paper, the construction of several shuttle Escherichia coli-Streptomyces artificial chromosomes is discussed together with old and new strategies applied to improve heterologous production of secondary metabolites. [ABSTRACT FROM AUTHOR]

Background: Proteomics was recently used to reveal enzymes whose expression is associated with the production of the glycopeptide antibiotic balhimycin in Amycolatopsis balhimycina batch cultivations. Combining chemostat fermentation technology, where cells proliferate with constant parameters in a highly reproducible steady-state, and differential proteomics, the relationships between physiological status and metabolic pathways during antibiotic producing and non-producing conditions could be highlighted. Results: Two minimal defined media, one with low Pi (0.6 mM; LP) and proficient glucose (12 g/l) concentrations and the other one with high Pi (1.8 mM) and limiting (6 g/l; LG) glucose concentrations, were developed to promote and repress antibiotic production, respectively, in A. balhimycina chemostat cultivations. Applying the same dilution rate (0.03 h-1), both LG and LP chemostat cultivations showed a stable steady-state where biomass production yield coefficients, calculated on glucose consumption, were 0.38 ± 0.02 and 0.33 ± 0.02 g/g (biomass dry weight/glucose), respectively. Notably, balhimycin was detected only in LP, where quantitative RT-PCR revealed upregulation of selected bal genes, devoted to balhimycin biosynthesis, and of phoP, phoR, pstS and phoD, known to be associated to Pi limitation stress response. 2D-Differential Gel Electrophoresis (DIGE) and protein identification, performed by mass spectrometry and computer-assisted 2 D reference-map http://www.unipa.it/ ampuglia/Abal-proteome-maps matching, demonstrated a differential expression for proteins involved in many metabolic pathways or cellular processes, including central carbon and phosphate metabolism. Interestingly, proteins playing a key role in generation of primary metabolism intermediates and cofactors required for balhimycin biosynthesis were upregulated in LP. Finally, a bioinformatic approach showed PHO box-like regulatory elements in the upstream regions of nine differentially expressed genes, among which two were tested by electrophoresis mobility shift assays (EMSA). Conclusion: In the two chemostat conditions, used to generate biomass for proteomic analysis, mycelia grew with the same rate and with similar glucose-biomass conversion efficiencies. Global gene expression analysis revealed a differential metabolic adaptation, highlighting strategies for energetic supply and biosynthesis of metabolic intermediates required for biomass production and, in LP, for balhimycin biosynthesis. These data, confirming a relationship between primary metabolism and antibiotic production, could be used to increase antibiotic yield both by rational genetic engineering and fermentation processes improvement. [ABSTRACT FROM AUTHOR]

Background: The alterations of the glutathione peroxidase enzyme complex system occur in physiological conditions such as aging and oxidative stress consequent to strenuous exercise. Methods: Authors optimize the spectrophotometric method to measure glutathione peroxidase activity in rat red blood cell membranes. Results: The optimization, when applied to age paired rats, both nulligravid and pregnant, shows that pregnancy induces, at seventeen d of pregnancy, an increase of both reactive oxygen substance concentration in red blood cells and membrane glutathione peroxidase activity. Conclusion: The glutathione peroxidase increase in erythrocyte membranes is induced by systemic oxidative stress long lasting rat pregnancy. [ABSTRACT FROM AUTHOR]

• Internal ballistics simulation of hybrid rocket engines burning liquefying fuels • Application of CFD to the simulation of the hybrid rocket engines internal ballistics • Development of an in-depth fuel pyrolysis model to calculate the surface temperature of liquefying fuels • Refinement and application of a liquid-entrainment model for the fuel regression rate calculation • Demonstration of the employed CFD model capability to reproduce the experimental data from engine hot fires A novel methodology for the calculation of the surface temperature of liquefying fuels typically burned in hybrid rockets is proposed. This procedure stems from the formulation of a fuel in-depth pyrolysis model coupled with the resolution of the thermo-fluid-dynamic field in the rocket combustion chamber, which allows for the characterization of the unstable liquid layer formed on top of the fuel surface. The aim is the simulation of the internal ballistics of hybrid rocket engines fed by paraffin-based fuels without the need for parametrically assigning the surface temperature to match the experimental data as, indeed, required in the authors' previous work. With the presented technique, surface temperature and fuel vaporization rate are calculated locally along the wall, and, with the integration of a liquid fuel entrainment model, which requires the tuning of just one parameter (i.e. the so-called entrainment factor), the fuel regression rate is determined. The overall numerical approach, upon the assumption that the liquid fuel is in the supercritical pressure regime, is based on the solution of the Reynolds-averaged Navier–Stokes equations for single-phase multicomponent turbulent reacting flow. A series of numerical simulations are carried out to unveil the effect of the oxygen mass flux, which allowed deriving an approximate analytical equation for the regression rate prediction. A set of hot fires of a laboratory-scale hybrid rocket are reproduced through single numerical simulations carried out on the fuel port average geometry in the burn to validate the computational model, showing deviations between the measured and predicted average regression rate less than 4.5%. In order to fairly match also the fuel consumption axial profile, transient numerical simulations over the entire engine firing are conducted with which the post-burn port shape is captured with maximum error of 8%. [ABSTRACT FROM AUTHOR]

Background: To investigate the feasibility, image quality, and clinical implications of a combined ECG-gated and helical acquisition mode in a computed tomography angiography (CTA) protocol in patients scheduled for transcatheter aortic valve implantation (TAVI) using a fixed, low-volume, contrast medium injection.Methods: Between July and October 2019, 43 TAVI candidates underwent investigation with CTA using a 64-slice CT scanner. Images obtained were prospectively evaluated. 65 mL of low iodine dose contrast medium (CM), followed by 25 mL of saline, were administered using a fixed multiphasic injection protocol in all patients. Patients were divided into three groups based on BMI: Group 1 (n = 9) with BMI < 22 kg/m2; Group 2 (n = 22) with BMI 22-29 kg/m2; Group 3 (n = 12) with BMI > 29 kg/m2. Images were evaluated for image quality, vessel attenuation (HU), Signal-to-Noise Ratio (SNR), Contrast-to-Noise Ratio (CNR) and estimated radiation dose. Image quality of the aortic root and iliac-femoral vessels was diagnostic in all patients.Results: Vascular attenuation was > 200 HU and CNR > 3 at all vessel levels.Conclusion: Data from our study suggest that it is possible to image the aortic annulus and aorto-iliac anatomy and obtain high image quality in all patients by using a combined ECG-gated and helical acquisition mode in a computed tomography angiography (CTA) protocol with a fixed low-volume contrast medium injection (65 mL). This allows for accurate CT measurements of the aortic annulus, recruitment of patients for TAVI and facilitates pre-procedural planning in these high surgical risk patients. [ABSTRACT FROM AUTHOR]

In a recent paper, the authors discussed the feasibility study of an innovative technique based on the directionality of Cherenkov light produced in a transparent material to improve the signal to noise ratio in muon imaging applications. In particular, the method was proposed to help in the correct identification of incoming muons direction. After the first study by means of Monte Carlo simulations with Geant4, the first reduced scale prototype of such a detector was built and tested at the Department of Physics and Astronomy "E. Majorana" of the University of Catania (Italy). The characterization technique is based on muon tracking by means of the prototype in coincidence with two scintillating tiles. The results of this preliminary test confirm the validity of the technique and stressed the importance to enhance the Cherenkov photons production to get a signal well distinguishable with respect to sensors and electronic noise. [ABSTRACT FROM AUTHOR]

The shift from conventional wastewater treatment plants to biorefineries is one of the most environmentally and economically sustainable pathways for extracting valuable compounds from waste. Besides chemical-physical processes, microorganisms within sewage sludge utilize organic and inorganic pollutants in the wastewater as nutrients, leading to effective water purification. However, the remaining solid sludge residue, typically destined for specific landfills or incineration, could undergo microbial fermentation to produce volatile fatty acids (VFA), metabolic precursors for biopolymers. Increasing attention has been directed towards optimizing operational parameters to enhance VFA production during sewage sludge fermentation. This study examined the impact of potassium permanganate (PP) on microbial communities during the sewage sludge's acidogenic fermentation. The results highlighted the positive effect of PP treatment, which increased COD production and VFA yield up to 1263.5 mg/L and 664.2 mg COD/L, respectively. The presence of PP significantly enhances VFA yield promoting bacteria positively linked to VFA production. • Bacterial fermentation of solid sludge residue from WWTP presents an opportunity to produce volatile fatty acids (VFA). • Potassium permanganate (KMnO₄) addition enhanced the VFA share up to 55 % of sCOD. • Macellibacteroides fermentans , Pseudomonas veronii and Proteocatella sphenisci increased in sludge treated with KMnO₄. • The addition of KMnO₄ in sewage sludge fermentation is a promising strategy for enhancing VFA yield by modulating bacterial communities. [ABSTRACT FROM AUTHOR]

Muography is an expanding technique for internal structure investigation of large volume object, such as pyramids, volcanoes and also underground cavities. It is based on the attenuation of muon flux through the target in a way similar to the attenuation of X-ray flux through the human body for standard radiography. Muon imaging have to face with high background level, especially compared with the tiny near horizontal muon flux. In this paper the authors propose an innovative technique based on the measurement of Cherenkov radiation by Silicon photo-multipliers arrays to be integrated in a standard telescope for muography applications. Its feasibility study was accomplished by means of Geant4 simulations for the measurement of the directionality of cosmic-ray muons. This technique could be particularly useful for the suppression of background noise due to back-scattered particles whose incoming direction is likely to be wrongly reconstructed. The results obtained during the validation study of the technique principle confirm the ability to distinguish the arrival direction of muons with an efficiency higher than 98% above 1 GeV. In addition, a preliminary study on the tracking performance of the presented technique was introduced. [ABSTRACT FROM AUTHOR]

Background: Klebsiella oxytoca DSM 29614 - isolated from acid mine drainages - grows anaerobically using Fe(III)-citrate as sole carbon and energy source, unlike other enterobacteria and K. oxytoca clinical isolates. The DSM 29614 strain is multi metal resistant and produces metal nanoparticles that are embedded in its very peculiar capsular exopolysaccharide. These metal nanoparticles were effective as antimicrobial and anticancer compounds, chemical catalysts and nano-fertilizers. Results: The DSM 29614 strain genome was sequenced and analysed by a combination of in silico procedures. Comparative genomics, performed between 85 K. oxytoca representatives and K. oxytoca DSM 29614, revealed that this bacterial group has an open pangenome, characterized by a very small core genome (1009 genes, about 2%), a high fraction of unique (43,808 genes, about 87%) and accessory genes (5559 genes, about 11%). Proteins belonging to COG categories "Carbohydrate transport and metabolism" (G), "Amino acid transport and metabolism" (E), "Coenzyme transport and metabolism" (H), "Inorganic ion transport and metabolism" (P), and "membrane biogenesis-related proteins" (M) are particularly abundant in the predicted proteome of DSM 29614 strain. The results of a protein functional enrichment analysis - based on a previous proteomic analysis – revealed metabolic optimization during Fe(III)-citrate anaerobic utilization. In this growth condition, the observed high levels of Fe(II) may be due to different flavin metal reductases and siderophores as inferred form genome analysis. The presence of genes responsible for the synthesis of exopolysaccharide and for the tolerance to heavy metals was highlighted too. The inferred genomic insights were confirmed by a set of phenotypic tests showing specific metabolic capability in terms of i) Fe2+ and exopolysaccharide production and ii) phosphatase activity involved in precipitation of metal ion-phosphate salts. Conclusion: The K. oxytoca DSM 29614 unique capabilities of using Fe(III)-citrate as sole carbon and energy source in anaerobiosis and tolerating diverse metals coincides with the presence at the genomic level of specific genes that can support i) energy metabolism optimization, ii) cell protection by the biosynthesis of a peculiar exopolysaccharide armour entrapping metal ions and iii) general and metal-specific detoxifying activities by different proteins and metabolites. [ABSTRACT FROM AUTHOR]

The Mediterranean diet features plant-based foods renowned for their health benefits derived from bioactive compounds. This review aims to provide an overview of the bioactive molecules present in some representative Mediterranean diet plants, examining their human nutrigenomic effects and health benefits as well as the environmental advantages and sustainability derived from their cultivation. Additionally, it explores the facilitation of producing fortified foods aided by soil and plant microbiota properties. Well-studied examples, such as extra virgin olive oil and citrus fruits, have demonstrated significant health advantages, including anti-cancer, anti-inflammatory, and neuroprotective effects. Other less renowned plants are presented in the scientific literature with their beneficial traits on human health highlighted. Prickly pear's indicaxanthin exhibits antioxidant properties and potential anticancer traits, while capers kaempferol and quercetin support cardiovascular health and prevent cancer. Oregano and thyme, containing terpenoids like carvacrol and γ-terpinene, exhibit antimicrobial effects. Besides their nutrigenomic effects, these plants thrive in arid environments, offering benefits associated with their cultivation. Their microbiota, particularly Plant Growth Promoting (PGP) microorganisms, enhance plant growth and stress tolerance, offering biotechnological opportunities for sustainable agriculture. In conclusion, leveraging plant microbiota could revolutionize agricultural practices and increase sustainability as climate change threatens biodiversity. These edible plant species may have crucial importance, not only as healthy products but also for increasing the sustainability of agricultural systems. [ABSTRACT FROM AUTHOR]

[Display omitted] Development of nanocomposite coating with antibiofilm properties is of fundamental importance to efficient fight biofilm formation preventing infections in biomedical area. In this context, halloysite nanotubes (HNTs), biocompatible and low-cost clay mineral, have been efficiently used as filler for different polymeric matrices affording several nanocomposites with appealing antimicrobial properties. The modification of HNTs surfaces represents a valuable strategy to improve the utilization of the clay for biological purposes. Experiments. Herein, the covalent modification of the HNTs lumen with properly designed dopamine derivatives with different perfluoroalkyl chain length is reported. The obtained nanomaterials are thoroughly characterized by several techniques. As proof of concept the antibiofilm properties on E. coli strain of the nanomaterials are assayed as well. Finally, the HNTs fillers were introduced into a polydopamine matrix allowing for the preparation of functional coatings, resistant to formation of microbial biofilms. All characterization methods proved the selectivity of the modification and the increased hydrophobicity of the lumen. In particular 27Al solid state nuclear magnetic resonance (NMR) spectra showed a upfield shift of the Al signal. Studies on the antibiofilm properties highlighted different activities according to the length of perfluoroalkyl chains of organic molecules as proved by 19F solid state NMR spectra. The synthetized materials were promising for future application as coatings on medical implants. [ABSTRACT FROM AUTHOR]

Pirins are evolutionarily conserved iron-containing proteins that are found in all kingdoms of life, and have been implicated in diverse molecular processes, mostly associated with cellular stress. In the present study, we started from the evidence that the insertional inactivation of pirin-like gene SAM23877_RS18305 ( pirA ) by ΦC31 Att/Int system-based vectors in spiramycin-producing strain Streptomyces ambofaciens ATCC 23877 resulted in marked effects on central carbon and energy metabolism gene expression, high sensitivity to oxidative injury and repression of polyketide antibiotic production. By using integrated transcriptomic, proteomic and metabolite profiling, together with genetic complementation, we here show that most of these effects could be traced to the inability of the pirA -defective strain to modulate beta-oxidation pathway, leading to an unbalanced supply of precursor monomers for polyketide biosynthesis. Indeed, in silico protein-protein interaction modeling and in vitro experimental validation allowed us to demonstrate that PirA is a novel redox-sensitive negative modulator of very long-chain acyl-CoA dehydrogenase, which catalyzes the first committed step of the beta-oxidation pathway. [ABSTRACT FROM AUTHOR]

Membrane vesicles (MVs) are spherical particles with nanoscale dimensions and characterized by the presence of diverse cargos, such as nucleic acids, proteins, lipids, and cellular metabolites. Many examples of (micro)organisms producing MVs are reported in literature. Among them, bacterial MVs are of particular interest because they are now considered as the fourth mechanism of horizontal gene transfer. Streptomyces bacteria are well-known for their ecological roles and ability to synthesize bioactive compounds, with Streptomyces coelicolor being the model organism. It was previously demonstrated that it can produce distinct populations of MVs characterized by different protein and metabolite cargos. In this work we demonstrated for the first time that MVs of S. coelicolor carry both DNA and RNA and that their DNA content represents the entire chromosome of the bacterium. These findings suggest that MV DNA could have a role in the evolution of Streptomyces genomes and that MVs could be exploited in new strain engineering strategies. [ABSTRACT FROM AUTHOR]

In this work, we prepared poly(caprolactone) (PCL) monofilaments incorporating different amounts of the antiseptic chlorhexidine diacetate (CHX) and evaluated the effect of 'online' drawing during the melt spinning or of an 'offline' cold drawing on the antimicrobial and physical properties of PCL/CHX monofilaments. The results showed that the drawing conditions strongly affected the properties of the threads. In particular, the filaments exhibited antimicrobial activity for all the draw ratios (DR) adopted, but on increasing DR the antibacterial efficiency reduced. These results were correlated with the CHX surface concentration and with the release kinetics. [ABSTRACT FROM AUTHOR]

Streptomyces coelicolor is a model organism for studying streptomycetes. This genus possesses relevant medical and economical roles, because it produces many biologically active metabolites of pharmaceutical interest, including the majority of commercialized antibiotics. In this bioinformatic study, the transcriptome of S. coelicolor has been analyzed to identify novel RNA species and quantify the expression of both annotated and novel transcripts in solid and liquid growth medium cultures at different times. The major characteristics disclosed in this study are: (i) the diffuse antisense transcription; (ii) the great abundance of transfer-messenger RNAs (tmRNA); (iii) the abundance of rnpB transcripts, paramount for the RNase-P complex; and (iv) the presence of abundant fragments derived from pre-ribosomal RNA leader sequences of unknown biological function. Overall, this study extends the catalogue of ncRNAs in S. coelicolor and suggests an important role of non-coding transcription in the regulation of biologically active molecule production. [ABSTRACT FROM AUTHOR]

We report the genome sequence of Planobispora rosea ATCC 53733, a mycelium-forming soil-dweller belonging to one of the lesser studied genera of Actinobacteria and producing the thiopeptide GE2270. The P. rosea genome presents considerable convergence in gene organization and function with other members in the family Streptosporangiaceae, with a significant number (44%) of shared orthologs. Patterns of gene expression in P. rosea cultures during exponential and stationary phase have been analyzed using whole transcriptome shotgun sequencing and by proteome analysis. Among the differentially abundant proteins, those involved in protein metabolism are particularly represented, including the GE2270-insensitive EF-Tu. Two proteins from the pbt cluster, directing GE2270 biosynthesis, slightly increase their abundance values over time. While GE2270 production starts during the exponential phase, most pbt genes, as analyzed by qRT-PCR, are down-regulated. The exception is represented by pbtA, encoding the precursor peptide of the ribosomally synthesized GE2270, whose expression reached the highest level at the entry into stationary phase. [ABSTRACT FROM AUTHOR]

NAI-107, produced by the actinomycete Microbispora sp. ATCC-PTA-5024, is a promising lantibiotic active against Gram-positive bacteria and currently in late preclinical-phase. Lantibiotics (lanthionine-containing antibiotics) are ribosomally synthesized and posttranslationally modified peptides (RiPPs), encoded by structural genes as precursor peptides. The biosynthesis of biologically active compounds is developmentally controlled and it depends upon a variety of environmental stimuli and conditions. Inorganic phosphate (Pi) usually negatively regulates biologically-active molecule production in Actinomycetes, while it has been reported to have a positive control on lantibiotic production in Firmicutes strains. So far, no information is available concerning the Pi effect on lantibiotic biosynthesis in Actinomycetes. Results After having developed a suitable defined medium, Pi-limiting conditions were established and confirmed by quantitative analysis of polyphosphate accumulation and of expression of selected Pho regulon genes, involved in the Pi-limitation stress response. Then, the effect of Pi on Microbispora growth and NAI-107 biosynthesis was investigated in a defined medium containing increasing Pi amounts. Altogether, our analyses revealed that phosphate is necessary for growth and positively influences both growth and NAI-107 production up to a concentration of 5 mM. Higher Pi concentrations were not found to further stimulate Microbispora growth and NAI-107 production. Conclusion These results, on one hand, enlarge the knowledge on Microbispora physiology, and, on the other one, could be helpful to develop a robust and economically feasible production process of NAI-107 as a drug for human use. [ABSTRACT FROM AUTHOR]