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Several shreds of evidence indicate that visual deprivation does not alter numerical competence neither in adults nor in children. However, studies reporting non-impaired numerical abilities in the visually impaired population present some limitations: (a) they mainly assessed the ability to process numbers (e.g. mathematical competence) rather than represent numbers (e.g. mental number line); (b) they principally focused on positive rather than negative number estimates; (c) they investigated numerical abilities in adult individuals except one focusing on children (Crollen et al. in Cognition 210:104586, 2021). Overall, this could limit a comprehensive explanation of the role exerted by vision on numerical processing when vision is compromised. Here we investigated how congenital visual deprivation affects the ability to represent positive and negative numbers in horizontal and sagittal planes in visually impaired children (thirteen children with low vision, eight children with complete blindness, age range 6–15 years old). We adapted the number-to-position paradigm adopted by Crollen et al. (Cognition 210:104586, 2021), asking children to indicate the spatial position of positive and negative numbers on a graduated rule positioned horizontally or sagittally in the frontal plane. Results suggest that long-term visual deprivation alters the ability to identify the spatial position of numbers independently of the spatial plane and the number polarity. Moreover, results indicate that relying on poor visual acuity is detrimental for low vision children when asked to localize both positive and negative numbers in space, suggesting that visual experience might have a differential role in numerical processing depending on number polarity. Such findings add knowledge related to the impact of visual experience on numerical processing. Since both positive and negative numbers are fundamental aspects of learning mathematical principles, the outcomes of the present study inform about the need to implement early rehabilitation strategies to prevent the risk of numerical difficulties in visually impaired children.

Plastic contamination by micro(nano)plastics represents one of the main threats that ecosystems have to currently face. The impact of micro(nano)plastics on organisms and ecosystems is not fully understood neither in the field nor the laboratory because of the lack of analytical methods that allow to accurately detect and quantify the exposure. This is particularly true for small sized microplastics and nanoplastics, whose quali-quantification is troublesome. Different analytical techniques can be used to measure micro(nano)plastics levels in different matrices, but recently the application of thermal analysis emerged as a promising approach. This review highlights the importance and the advantages of thermal analyses to assess the exposure to micro(nano)plastics in ecotoxicological and toxicological studies.

γ-Glutamyl-peptides are frequently endowed with biological activities. In this work, "

γ-Glutamyl derivatives of proteinogenic or modified amino acids raise considerable interest as flavor enhancers or biologically active compounds. However, their supply, on a large scale and at reasonable costs, remains challenging. Enzymatic synthesis has been recognized as a possible affordable alternative with respect to both isolation procedures from natural sources, burdened by low-yield and by the requirement of massive amount of starting material, and chemical synthesis, inconvenient because of the need of protection/deprotection steps. The E. coli γ-glutamyltransferase (Ec-GGT) has already been proposed as a biocatalyst for the synthesis of various γ-glutamyl derivatives. However, enzymatic syntheses using this enzyme usually provide the desired products in limited yield. Hydrolysis and autotranspeptidation of the donor substrate have been identified as the side reactions affecting the final yield of the catalytic process. In addition, experimental conditions need to be specifically adjusted for each acceptor substrate. Substrate specificity and the fine characterization of the activities exerted by the enzyme over time has so far escaped rationalization. In this work, reactions catalyzed by Ec-GGT between the γ-glutamyl donor glutamine and several representative acceptor amino acids have been finely analyzed with the identification of single reaction products over time. This approach allowed to rationalize the effect of donor/acceptor molar ratio on the outcome of the transpeptidation reaction and on the distribution of the different byproducts, inferring a general scheme for Ec-GGT-catalyzed reactions. The propensity to react of the different acceptor substrates is in agreement with recent findings obtained using model substrates and further supported by x-ray crystallography and will contribute to characterize the still elusive acceptor binding site of the enzyme.

Umami taste, known as appetizing sensation, is mainly imparted by monosodium glutamate (MSG, the first identified umami factor) in synergistic combination with some 5' ribonucleotides such as inosine 5'-monophosphate, IMP, guanosine 5'-monophosphate, GMP, and adenosine 5'-monophoshate, AMP. The level of free glutamic acid in tomatoes is higher than in other vegetables or fruits and increases with ripening and industrial processing. In addition, due to the presence of bioactive metabolites, tomatoes and tomato-based products are among the most consumed healthy food items. The levels of the major umami compounds of tomato, that is, glutamate and 5'-ribonucleotides (GMP and AMP) were assessed in different parts (skin, outer flesh, and inner pulp) of known tomato varieties from southern Italy: San Marzano Originale, San Marzano 245, Black Tomato, Corbarino Corbara, Corbarino Nocera, and Superpomodoro (tomato hybrid). Such varieties were also investigated for their antioxidant properties through DMPD, DPPH, and ABTS assays, with San Marzano Originale showing the highest antioxidant power both in lipophilic and methanolic fractions. The concentration of umami compounds in tomato differs with the part of the fruit analyzed and is greatly dependent on the variety, being Corbarino Nocera the cultivar richest in glutamate and Superpomodoro in ribonucleotides. As for nutritional aspect, results confirm the great nutraceutical feature of San Marzano tomato, the most known variety used in industrial processes. PRACTICAL APPLICATIONS: This study was planned to develop a method to quantify the major umami compounds that strongly influence the organoleptic properties of many different tomato varieties. It is known that the sensory quality of fruits and vegetables is an important factor in consumer's choice. The analytical methods described here enabled the evaluation of the glutamate and 5'-ribonucleotides contents in six selected varieties of tomato from Campania region, and can be easily used to determine the sensory profile of commercial varieties, for example, those perceived as not very tasteful by consumers.

γ-glutamyltransferase (GGT) is an enzyme that uses γ-glutamyl compounds as substrate and catalyzes their transfer into a water molecule or an acceptor substrate with varied physiological-function in bacteria, plants and animals. Crystal structures of GGT are known for different species and in different states of the chemical reaction; however, structural dynamics of the substrate binding to the catalytic site of GGT is unknown. Here, we modeledEscherichia ColiGGT’s glutamine binding by using a swarm of accelerated molecular dynamics (aMD) simulations. Characterization of multiple binding events identified three structural binding motifs composed of polar residues in the binding pocket that govern glutamine binding into the active site. Simulated open and closed conformations of a lid-loop protecting the binding cavity suggests its role as a gating element by allowing or blocking substrates entry into the binding pocket. Partially open states of the lid-loop are accessible within thermal fluctuations, while the estimated free energy cost of a complete open state is 2.4 kcal/mol. Our results suggest that both specific electrostatic interactions and GGT conformational dynamics dictate the molecular recognition of substrate-GGT complexes.

Radiofrequency ablation is a minimally invasive procedure alternative to surgery to treat benign thyroid nodules causing compressive symptoms. Tolerability of this procedure, aimed at treatment of benign conditions, is fundamental. In this study, we evaluated if local anesthesia should be enough to reduce both hospital costs and sedation-related risks for the patient, avoiding deep sedation and presence of the anesthesiologist. From July 2017 to August 2018, 14 consecutive patients (mean age 60.1 years) were treated and divided in two groups: Group A (7 patients) underwent systemic sedoanalgesia (intravenous remifentanil/fentanyl ± intravenous midazolam ± intravenous acetaminophen/nonsteroidal anti-inflammatory drugs) + subcutaneous anesthesia (lidocaine), with anesthesiologist. Group B (7 patients) underwent mild systemic sedoanalgesia (oral solution morphine sulfate + intravenous midazolam + intravenous acetaminophen) + both subcutaneous and subcapsular anesthesia (mepivacaine + bupivacaine), without anesthesiologist. Tolerability, sedation grade (Ramsay scale), total opioid dose, complications, and results at 12 months were analyzed and compared. Mean tolerability was 9.4 in group A and 8.9 in group B (p: 0.786). Mean sedation grade was 3.86 in group A and 2.71 in group B (p: 0.016). Mean total opioid dose was 70.9 mg in group A and 10 mg in group B (p:0.00015). No complications were observed. At 12 months, mean volume reduction was 56.1% in the group A and 60% in the group B. In thyroid radiofrequency ablation, subcapsular anesthesia can decrease both total opioid dose and level of patient's sedation without significant differences in tolerability, allowing to perform ablation without the anesthesiologist.

The lipase-catalyzed regioselective hydrolysis of peracetylated arabinose was performed in a packed bed flow reactor (PBR). In particular, the hydrolysis of the α anomer of peracetylated arabinose catalyzed by Novozym® 435 resulted in the monodeprotection of C5 in only 5 min and 91% yield. By using the immobilized Pseudomonas stutzeri lipase, the regioselective hydrolysis of the β anomer was also accomplished affording the C1 deacetylated derivative in 30 min with good yields. The high local concentration of the immobilized biocatalyst in the PBR allow for a significant reduction of the reaction time; moreover, repeated re-use, and easy downstream processing increase the efficiency and the productivity of the process, if compared to the classical batch procedure. In fact, under optimized conditions, the specific reaction rate of the biocatalyzed flow reaction showed an increase of more than 300 times compared to the batch one. The obtained building blocks were prepared in gram scale and then used for the synthesis of peracetylated arabinofuranosyl-1,5-arabinofuranose.

The aim of this work was the comprehensive characterization of dried Senise pepper, a tasty landrace, to verify the suitability of common industrial processing and different growing locations to its production. Fruits from experimental CREA fields of Battipaglia (southern Italy) and Montanaso (northern Italy), dried using a solar dryer or a forced air oven, were compared with lyophilized and commercial samples. Solar dried samples showed a retention of glucose, while fructose levels decreased. Citric acid was the main acid in all samples, showing a differentiated behavior upon processing, with higher content in Battipaglia samples. The ascorbic acid showed the highest correlation with antioxidant assays, and both drying methods decreased its content, with better retention in Battipaglia samples. Drying did not markedly affect carotenoid levels, showing higher content in Battipaglia peppers. Both drying technique and mostly growing location influenced the volatile profile, with higher apocarotenoid content in Battipaglia samples. PRACTICAL APPLICATIONS: The use of Senise red pepper, a tasty landrace awarded in 1996 with the PGI certification mark, is spreading even outside Italy due to the renewed interest for high quality products with excellent taste and healthy properties. These peppers are mostly sun-dried following a traditional procedure and consumed as spice. New approaches regarding the type of drying and the growing location of this spice, together with the knowledge about the changes in quality indexes with processing, can be useful for a better exploitation of this product, increasing its market availability and lowering the cost of production.

Following a fatal case of Cryptococcus neoformans meningitis in a child with X-linked hyper-immunoglobulin M syndrome (XHIGM), we evaluated the fungal isolate in an experimental infection in a mouse model with respect to microbiology, epidemiology, virulence and response to therapy. The minimum inhibitory concentrations for antifungals in the susceptibility test were 0.5 mg/L for amphotericin B, 4.0 mg/L for fluconazole and 0.12 mg/L for voriconazole. Evaluation of pathogenicity by means of an experimental infection in BALB/c mice showed that fungus isolated from the blood and cerebrospinal fluid of the child was able to disseminate, reaching the spleen, lungs and brain, where it caused significant macroscopic alterations in the size and texture of each organ. Treatment of infected mice with amphotericin B reduced the fungal load in the spleen and lungs, but not in the brain.

Poly(γ-glutamic acid) is a linear anionic biopolymer synthesized by bacterial fermentation from sustainable resources. Being water soluble, biodegradable, edible and non-toxic to humans and the environment, applications of γ-PGA are of interest in a broad range of industrial sectors. However, preparation of γ-PGA derivatives is plagued by several difficulties including its scarce solubility in organic solvents. We here report a γ-PGA derivatization procedure based on the use of its tetrabutylammonium salt. The modified solubility of γ-PGA provided by counterion exchange led to the synthesis of poly(α-ethyl-γ-glutamate), poly(α-benzyl-γ-glutamate) and poly(α-n-butyl-γ-glutamate) under smoother conditions and an almost complete functionalization degree.

The identification of new strategies to fight bacterial infections in view of the spread of multiple resistance to antibiotics has become mandatory. It has been demonstrated that several bacteria develop poly‐γ‐glutamic acid (γ‐PGA) capsules as a protection from external insults and/or host defence systems. Among the pathogens that shield themselves in these capsules are Bacillus anthracis, Francisella tularensis and several Staphylococcus strains. These are important pathogens with a profound influence on human health. The recently characterised γ‐PGA hydrolases, which can dismantle the γ‐PGA‐capsules, are an attractive new direction that can offer real hope for the development of alternatives to antibiotics, particularly in cases of multidrug resistant bacteria. We have characterised in detail the cleaving mechanism and stereospecificity of the enzyme PghL (previously named YndL) from Bacillus subtilis encoded by a gene of phagic origin and dramatically efficient in degrading the long polymeric chains of γ‐PGA. We used X‐ray crystallography to solve the three‐dimensional structures of the enzyme in its zinc‐free, zinc‐bound and complexed forms. The protein crystallised with a γ‐PGA hexapeptide substrate and thus reveals details of the interaction which could explain the stereospecificity observed and give hints on the catalytic mechanism of this class of hydrolytic enzymes.

γ-Glutamyltransferase (GGT) catalyzes the transfer of the γ-glutamyl moiety from a donor substrate such as glutathione to water (hydrolysis) or to an acceptor amino acid (transpeptidation) through the formation of a γ-glutamyl enzyme intermediate. The vast majority of the known GGTs has a short sequence covering the glutamate binding site, called lid-loop. Although being conserved enzymes, both B. subtilis GGT and the related enzyme CapD from B. anthracis lack the lid loop and, differently from other GGTs, both accept poly-γ-glutamic acid (γ-PGA) as a substrate. Starting from this observation, in this work the activity of an engineered mutant enzyme containing the amino acid sequence of the lid loop from E. coli GGT inserted into the backbone of B. subtilis GGT was compared to that of the lid loop-deficient B. subtilis GGT and the lid loop-carrier E. coli GGT. Results indicate that the absence of the lid loop seems not to be the sole structural feature responsible for the recognition of a polymeric substrate by GGTs. Nevertheless, time course of hydrolysis reactions carried out using oligo-γ-glutamyl glutamines as substrates showed that the lid loop acts as a gating structure, allowing the preferential selection of the small glutamine with respect to the oligomeric substrates. In this respect, the mutant B. subtilis GGT revealed to be more similar to E. coli GGT than to its wild-type counterpart. In addition, the transpeptidase activity of the newly produced mutant enzyme revealed to be higher with respect to that of both E. coli and wild-type B. subtilis GGT. These findings can be helpful in selecting GGTs intended as biocatalysts for preparative purposes as well as in designing mutant enzymes with improved transpeptidase activity.

Background The increased survival in Systemic Lupus Erythematosus (SLE) patients implies the development of chronic damage, occurring in up to 50% of cases after a follow-up of 10 years. Its prevention is a major goal in the SLE management. During the last years, it has been suggested that Artificial Neural Networks (ANNs) could be a useful prediction tool in medical scenarios, by using patients9 data as inputs and the specific outcomes as outputs. The International Conference on Advanced Computing and Communication Systems in 2015 underlined the possible application of sophisticated data analysis tools, such as machine learning methods, in SLE patients, in the light of their potential application to diagnostic and prediction purposes. Objectives In the present study, we aimed at predicting chronic damage in a large monocentric SLE cohort by using neural networks. Methods For the present analysis, we used data from 413 SLE patients (1997 ACR criteria; M/F 30/383; mean age ± SD 46.3±11.9 years; mean disease duration ± SD 174.6±112.1 months, mean follow-up period ±SD 63.9±30.7 months). At each visit, the patients underwent a complete physical examination and clinical and laboratory data were collected in a standardized, computerized, and electronically filled form. All the patients were evaluated at least twice per year. Autoantibodies and complement serum levels were also registered. Chronic damage was assessed by the SLICC/ACR Damage Index (SDI). We applied Recurrent Neural Networks (RNNs) as a machine-learning model to predict the risk of chronic damage. The clinical data sequences registered for each patient during the follow-up were used for building and testing the RNNs. We used 27 clinical and laboratory items for the mathematical model. Results At the first visit, 35.8% of patients had an SDI≥1, with a mean±SD value of 1.7±1.1. For the RNN model, two groups of patients were analyzed: patients with SDI=0 at the baseline, developing damage during the follow-up (N=38), and patients without damage (SDI=0). In particular, in the first group, we used all the visits before the development of damage, and in the second group, we considered patients with at least 5 visits and a follow-up of 2 years. We created a mathematical model with an AUC value of 0.77, able to predict damage development. A threshold value of 0.35 (sensitivity 0.74, specificity 0.76) seems able to identify patients at risk to develop damage. Conclusions We applied RNNs to identify a prediction model for SLE chronic damage. By using longitudinal data, including laboratory and clinical items, we created a mathematical model able to identify patients at higher risk to develop chronic damage. Disclosure of Interest None declared

We described the development of a biochromatographic system which uses a purine nucleoside phosphorylase from Aeromonas hydrophila (AhPNP) for the evaluation of the substrate specificity on nucleoside libraries. AhPNP has been covalently immobilized on a fused silica Open Tubular Capillary (OTC) via Schiff base chemistry. The resulting bioreactor has been characterized by the determination of kinetic constants (Km and Vmax) for a natural substrate (inosine) and then assayed versus all natural purine (deoxy)ribonucleosides and a small library of 6-substituted purine ribosides. Characterization of the bioreactor has been carried out through a bidimensional chromatographic system with the sample on-line transfer from the bioreactor to the analytical column for the separation and quantification of substrate and product. Comparison with the soluble enzyme showed that the AhPNP-based bioreactor is reliable as the same ranking order, with respect to the standard activity assay, was obtained. The stability of the IMER was also assessed and the system was found to be stable up to 60 reactions.

Purified lipase fractions from crude commercial extract of Aspergillus niger lipase (ANL) were selectively immobilized on hydrophobic supports. A significant percentage of esterase activity remains in the supernatant, derived from esterase(s) unable to become adsorbed onto the employed matrices. These residual proteins were covalently immobilized on epoxy-acrylic resin. Immobilized hydrolases were tested in the hydrolysis of acetylated disaccharides in water-cosolvent systems. ANL-Esterase was able to catalyze regioselective deprotection of acetylated β-O-methyl lactoside in C-2 position and β-O-methyl lactosaminide in C-3′ position. The hydrolyzed products, never reported before, can be considered new building blocks for the synthesis of oligosaccharides of biological relevance. Furthermore, preparative hydrolyses were also performed in tert-butanol. This solvent is compatible with ANL-esterase stability and it appears to be a novel and promising approach because of its green status.

In Helping Bereaved Children: A Handbook for Practitioners, editor Nancy Boyd Webb has crafted a comprehensive compendium of contemporary research, theory, case studies, and targeted interventions ...

Purine nucleoside phosphorylase (PNP) from Aeromonas hydrophila encoded by the deoD gene has been over-expressed in Escherichia coli, purified, characterized about its substrate specificity and used for the preparative synthesis of some 6-substituted purine-9-ribosides. Substrate specificity towards natural nucleosides showed that this PNP catalyzes the phosphorolysis of both 6-oxo- and 6-aminopurine (deoxy)ribonucleosides. A library of nucleoside analogues was synthesized and then submitted to enzymatic phosphorolysis as well. This assay revealed that 1-, 2-, 6- and 7-modified nucleosides are accepted as substrates, whereas 8-substituted nucleosides are not. A few transglycosylation reactions were carried out using 7-methylguanosine iodide (4) as a d-ribose donor and 6-substituted purines as acceptor. In particular, following this approach, 2- amino-6-chloropurine-9-riboside (2c), 6-methoxypurine- 9-riboside (2d) and 2-amino-6-(methylthio)purine- 9-riboside (2g) were synthesized in very high yield and purity.

An INFN-LNF/UCLA/SAPIENZA collaboration is developing a hybrid photoinjector in X-band. A hybrid photoinjector is a novel high brightness electron source that couples a standing wave cell cavity (acting as an RF gun) directly to a multi-cell travelling-wave structure. This configuration offers a number of advantages over the split standing wave/travelling-wave system. Most notably the reflected RF transient is almost completely suppressed, thus eliminating the need for a circulator and the bunch lengthening effect that occurs in the drift section of the split system. These properties allow scaling of the device to higher field and frequencies, which should dramatically improve beam brightness. The RF coupling between the standing and the traveling wave sections is accomplished in the fourth cell encountered by the beam, with the SW section electrically coupled to it on-axis. This mode of coupling is particularly advantageous, as it is accompanied by a 901 phase shift in the accelerating field, resulting in strong velocity bunching effects on the beam that reverse the usual bunch lengthening induced after the gun exit in standard 1.6 cell photoinjectors. In this scenario, from the beam dynamics point of view, it is seen that device may produce ten’s of femtosecond beams at � 3.5 MeV and the emittance compensation dynamics remains manageable even in the presence of strong compression. We present here a survey of the device characteristics. In particular we show the results of the electromagnetic simulations, a beam dynamics analysis related to the temperature tuning of the SW and TW section, and a RF characterization using bead pull and scattering coefficient measurements of a device prototype.

Tomato is one of the most widely consumed fresh vegetables in the industrialized world and an important source of healthy constituents of the human diet. Despite the unique flavor characteristics of tomatoes, which make them extremely valuable in cooking, and their recognized beneficial role in the diet, the quality of tomato was traditionally only considered in connection to external appearances. As it happened with other highly requested crops, breeding programs of tomato focused their efforts on developing new varieties with higher yields and stress resistance, with better uniformity in fruit size, brighter color and prolonged shelf life. The downside of these strategies was that organoleptic features and nutritional value were often neglected, with a detrimental effect on commercial tomatoes. Over the last years, there has been an increase in consumers’ demand for tasty and healthy products. This aspect, paired with novel and multidisciplinary approaches to tomato research, allowed both sensory and nutritional qualities to be reconsidered as valuable parameters in breeding. In this review we describe the main chemical constituents of tomato, focusing on the flavor compounds (both volatile and non-volatile compounds) and secondary metabolites. Particular attention is paid to their beneficial effects on human health and their relevance to the overall quality of tomato.

(R)-2-Tetralol (R)-2a, (R)-5-hydroxy-2-tetralol (R)-2b and (R)-8-hydroxy-2-tetralol (R)-2c, which are key intermediates in the synthesis of pharmacologically active 2-aminotetralins 3, were prepared in moderate to very high enantiomeric excess (up to 99% ee) by enzymatic resolution of the corresponding racemic butyrates rac-1a, rac-1b and rac-1c, respectively, using lipases immobilized on octyl agarose. This methodology is an alternative to the microbial reduction of 2-tetralones.

(1 R )-1-Deuterated alcohols with high enantiomeric excess were prepared via TiCl 4 /Et 3 SiD reduction of acetals arising from the reaction of aldehydes with (1 S ,2 S )-3,3,3-trifluoro-1-phenylpropane-1,2-diol 9 . Such a chiral auxiliary was synthesized in an enantiomerically pure form starting from l -mandelic acid. Due to its benzylic nature, it was easily removed from the reaction product of the reductive 1,3-dioxolane ring-cleavage to afford the desired α-deuterated alcohol.

Two triglycerides, both bearing polyunsaturated fatty acid residues, were isolated from the hexane extract of Urena lobata. One of them is characterized by the presence of three different polyunsaturated fatty acids. Their structures were studied with spectral methods.

α-Mangostin is the major prenylated xanthone from Garcinia mangostana and it has been used also in recent times as starting material for the semisynthetic preparation of various biologically active derivatives. Its structure is characterised by the presence of few functional groups amenable to chemical manipulations, but present in the molecule in multiple instances (three phenolic hydroxyl groups, two prenyl chains and two unsubstituted aromatic carbons). This study represents a first approach to the systematic investigation of the reactivity of α-mangostin and describes the semisynthesis of some minor xanthones isolated from G. mangostana.

Este trabalho visou o estudo de cerâmicas sinterizadas por fluxo viscoso com ênfase na formação de fases e desenvolvimento microestrutural. Foram estudadas composições de grês porcelanato, preparadas a partir de mistura de argila plástica, caulim, feldspato, quartzo e talco: i) uma composição baseada em formulação encontrada em literatura, e ii) composições preparadas com a finalidade de se observar o efeito da adição de um formador de fase vítrea obtido em laboratório, em substituição ao feldspato. A formação de uma grande quantidade de fase líquida viscosa, durante o processo de queima do grês porcelanato a elevadas temperaturas, favoreceu a eliminação da maioria dos poros e, como conseqüência, a densificação do corpo. A adição da fase vítrea resultou em amostras com boas propriedades físicas e necessidade de menores temperaturas de queima. Portanto, é possível substituir a matéria-prima de maior custo - o feldspato - por uma fase vítrea inerte, sem comprometimento do processamento, propriedades físicas e estéticas do produto final. This work describes an investigation carried out for ceramics sintered by viscous flow with emphasis on phase formation and microstructural development. In this work, compositions prepared by mixing ball clay, kaolin, feldspar, quartz and talc were studied They consisted of a composition based on the formulation of stoneware tileand reported in the literature and compositions intentionally prepared to observe the effect of the addition of a vitreous phase former, replacing feldspar on the phase formation and final characteristics. The formation of a great amount of liquid viscous phase during the firing process of the stoneware tiles at high temperatures provided the elimination of the majority of the pores and, consequently, the densification of the body. The addition of vitreous phase former resulted in samples with good physical properties fired at relatively low temperatures. In addition, it was possible to replace a costly raw material, i.e., feldspar by an inert vitreous phase former previously obtained, without affecting the processing, physical and visual properties of the final product.

Esterification of the Wang resin 5 with the monoamide of oxalic acid (oxamic acid, 7) followed by dehydration of the amide function furnishes the resin-bound cyanoformate 9, which can be elaborated by zinc-catalyzed reaction with β-keto esters. The obtained enamino keto diesters 10a–d react with hydrazines affording, after removal from the solid support, fully substituted pyrazoledicarboxylic acids 12a–n. Optimization of the above sequence and the solid-phase synthesis of a small test-library of 1,5-disubstituted pyrazole-3,4-dicarboxylic acid derivatives are described. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The hydrolytic enzymes contained in a crude extract from Rhizomucor miehei (RML) were immobilized onto different supports. The catalytic behavior of the different enzyme derivatives in the resolution of esters of racemic 2-tetralol and structurally related secondary alcohols was investigated. We observed that, when the immobilization occurs by adsorption on highly hydrophobic solid surfaces, such as octyl-agarose or octadecyl-Sepabeads, only the lipase fraction (36 kDa) was immobilized and the resulting catalysts showed good lipasic activity and high enantioselectivity. By contrast, when immobilization was performed by ionic or covalent attachment, all proteins contained in the crude extract were immobilized and both activity and enantioselectivity were found to be much lower. The different enantioselectivity seems to be related to conformational changes of the lipase fraction (36 kDa) in the different immobilization approaches. (R)-2-Tetralol was obtained with high enantiomeric excess (89% at 50% of conversion, E = 51) by hydrolysis of the corresponding butyric acid ester using RML on octyl-agarose.

The Cl 2 AlH-mediated ring-opening of 2-substituted cis -4-methyl-5-trifluoromethyl-1,3-dioxolanes was found to occur with regioselective cleavage of the O1–C2 bond by attack of the aluminum hydride from the direction anti to the departing oxygen. This stereochemical outcome, which appears to be unprecedented in the reductive cleavage of chiral acetals by aluminum reagents, is interpreted on the basis of theoretical calculations.

TiCl 4 -mediated nucleophilic ring-opening reactions of chiral acetals derived from (2S,3S)-1,1,1-trifluorobutane-2,3-diol proceed in a completely regioselective manner, leading to the break of the O1-C2 bond accompanied by a high degree of stereoselectivity. The use of triethylsilyl deuteride or allyltributyltin as nucleophiles gives access, after removal of the chiral auxiliary, to stereoselectively deuterated primary alcohols or homoallylic secondary alcohols, respectively, with high enantiomeric excesses.

A new constituent, aloeresin H (1), was isolated from Cape aloe, a bittering and laxative agent. Its structure was elucidated by degradation experiments combined with 1D and 2D NMR data. Aloeresin H represents the first C,C-diglucoside discovered in commercial samples of the drug and its polyketide origin can be interpreted in terms of two-chain condensation. Possible conformations of the virtual aglycone were obtained as energy minima by quantum mechanical calculations and were found to be consistent with particular NOE associations observed in the original glucoside.

Tin(IV) chloride selectively promotes the nucleophilic attack of methyl acetoacetate to the cyano instead of the olefinic carbon atom of α,β-unsaturated nitriles to give enaminoketoesters. In the presence of an excess of ketoester a second C–C bond formation occurs followed by cyclisation affording substituted pyridines in a selective cascade sequence.

2,3,5-Tri- O -benzoyl-β- d -ribofuranosyl cyanide reacts with methyl acetoacetate and diethyl malonate in the presence of stoichiometric amounts of SnCl 4 to give a β- d -ribofuranosyl-enaminoketoester and a β- d -ribofuranosyl-enaminodiester, respectively. The β- d -ribofuranosyl-enaminoketoester was debenzoylated, treated with 2,2-dimethoxypropane and tert -butyl-dimethylsilyl chloride to give the methyl 3-amino-3-(5′- O - tert -butyldimethylsilyl-2′,3′- O -isopropylidene-β- d -ribofuranosyl)-2-acetyl propanoate obtained in good yield together with small amounts of its α-anomer. The reactions of the β-anomer with hydrazine, methyl- and phenylhydrazine, carried out under controlled experimental conditions, afforded the pyrazole C-nucleosides in good yields as β-anomers.

The aim of this study was to evaluate the quality of cooled canine semen processed with diluents containing a new isoforme of rMn SOD. Our results suggest that rMnSOD has a preserving effect on the quality of chilled dog spermatozoa.

N2-alkyl and N2-alkanoyl derivatives of guanosine 5′-phosphate bearing a sulfoxide group into the side chain (3b,e; 4b) were synthesized and tested for their synergistic effect with monosodium-l-glutamate (MSG), which is the prototypical substance imparting umami taste to savoury-based foods. Capacities to enhance the taste intensity of MSG were estimated (as γ values) through subjective comparisons of MSG/5′-nucleotide mixtures in water with appropriate solutions of MSG alone, followed by statistical treatment (Probit method) of the resulting responses. The synergistic activity of each sulfoxide toward MSG resulted to be lower than that of the corresponding sulfide. Copyright © 2011 John Wiley & Sons, Ltd.

Purified lipase fractions from crude commercial extract of Aspergillus niger lipase (ANL) were selectively immobilized on hydrophobic supports. A significant percentage of esterase activity remains in the supernatant, derived from esterase(s) unable to become adsorbed onto the employed matrices. These residual proteins were covalently immobilized on epoxy-acrylic resin. Immobilized hydrolases were tested in the hydrolysis of acetylated disaccharides in water-cosolvent systems. ANL-Esterase was able to catalyze regioselective deprotection of acetylated β-O-methyl lactoside in C-2 position and β-O-methyl lactosaminide in C-3′ position. The hydrolyzed products, never reported before, can be considered new building blocks for the synthesis of oligosaccharides of biological relevance. Furthermore, preparative hydrolyses were also performed in tert-butanol. This solvent is compatible with ANL-esterase stability and it appears to be a novel and promising approach because of its green status.

In this paper a series of 2-iminomethoxyethyl mannose-based mono- and disaccharides have been synthesized by a chemoenzymatic approach and used in coupling reactions with ε-amino groups of lysine residues in a model protein (ribonuclease A, RNase A) to give semisynthetic neoglycoconjugates. In order to study the influence of structure of the glycans on the conjugation outcomes, an accurate characterization of the prepared neoglycoproteins was performed by a combination of ESI-MS and LC-MS analytical methods. The analyses of the chymotryptic digests of the all neoglycoconjugates revealed six Lys-glycosylation sites with a the following order of lysine reactivity: Lys 1 ≫ Lys 91 ≅ Lys 31 > Lys 61 ≅ Lys 66. A computational analysis of the reactivity of each lysine residue has been also carried out considering several parameters (amino acids surface exposure and pKa, protein flexibility). The in silico evaluation seems to confirm the order in lysine reactivity resulting from proteomic analysis., This work was funded by Regione Lombardia, Italy (VATUB project, Project Framework agreement Lombardy Region Universities-DGR 9139) and by Fondazione Banca del Monte di Lombardia (Italy) FBML. M. F. thanks to CSIC for a JAE-Doc contract (“Junta para la Ampliacion de estudios”) cofounded by ESF (European Social Fund).

18O-Substituted propane-1,2-diols and meso-butane-1,2-diols were synthesized and fed to growing cells of Lactobacillus brevis. Propan-1-ol and butan-2-ol, prepared from such diols through diol-dehydratase-catalyzed dehydration followed by intracellular reduction, were analyzed for their 18O-content. For each propane-1,2-diol enantiomer, partial retention or complete loss of the isotope appeared to be related to the mode of substrate binding. Specific retention of the O-atom linked to the (R)-configured C-atom of meso-butane-1,2-diol indicates that the diol dehydratase handles this substrate like (R)-propane-1,2-diol.

This Conference is the fifth of a series of Workshops on High Energy Gamma- ray Experiments, following the Conferences held in Perugia 2003, Bari 2004, Cividale del Friuli 2005, Elba Island 2006. This year the focus was on the use of gamma-ray to study the Dark Matter component of the Universe, the origin and propagation of Cosmic Rays, Extra Large Spatial Dimensions and Tests of Lorentz Invariance., Comment: 328 pages, 7.8Mb, Proceedings of the 5th SCINEGHE Workshop, June 18-20, 2007 http://www.roma2.infn.it/SciNeGHE07/

A new route to the synthesis of pyrazole and pyrimidine C-nucleosides, which involves as the key step a metal promoted reaction of β-D-ribofuranosyl ketoesters with alkyl cyanoformates is described. 2,3,5-Tri-O-benzoyl-β-D-ribofuranosyl cyanide 1 reacts with α-bromoesters, in the presence of zinc dust, to give β-D-ribofuranosyl-enaminoesters 2 which are hydrolysed with 1N hydrochloric acid to β-ketoesters 3. The reactions of β-ketoesters 3 with alkyl cyanoformates, in the presence of tin(IV) chloride or of catalytic amounts of metal acetylacetonates, afford β-D-ribofuranosyl enaminoketoesters 4. These compounds react with benzylhydrazine and acetamidine to give pyrazole and pyrimidine C-nucleosides (6,7).

BACKGROUND Collection of multiple products including plasma, packed red blood cells (PBRC) and double units of platelets, is increasingly improving donor utilisation and decreasing blood transfusion costs. Total apheresis is the new trend in blood banking and both industry and physicians are progressively expanding their involvement in this field. During 1998, at our hemapheresis unit, we used three new apparatuses for multicomponent collection (MCC). These apparatuses vary in terms of principle, operation and specific capabilities, and thus knowledge of them is essential to match their characteristics with plateletapheresis needs. STUDY DESIGN We reviewed all MCCs carried out in 1998 with MCS+, Trima and Excel-Pro cell separators. These apparatuses were evaluated in terms of platelet yield, white blood cell (WBC) contamination, efficiency per minute, platelet activation, and PBRC product quality. RESULTS The three machines are compared in the following table [table in text]. CONCLUSIONS MCC with the new apparatuses is well accepted by donors and personnel. There are no risks for the donors and, excluding ACD reactions and/or vaso/vagal attacks at the beginning of procedures, no severe reaction was seen. The quality and quantity of platelet products are good. When PRBC or a second platelets unit are collected, the cost of the kit is covered by this double product.

Maytenus senegalensis (Lam.) Excell (Celastraceae) root extracts were investigated for their topical anti-inflammatory properties by measuring the inhibition of the Croton oil-induced ear oedema in mice. The highest anti-inflammatory activity was detected in the chloroform extract, which reduced the oedematous response with a potency similar to that of the NSAID reference drug indomethacin (ID(50)=84 and 93 microg/cm(2), respectively). Fractionation of the chloroform and of the hexane extracts led to the isolation of maytenoic acid (1), which exhibited a dose-dependent antiphlogistic effect (ID(50)=0.11 micromol/cm(2)) twice that of indomethacin (ID(50)=0.26 micromol/cm(2)) and only three times lower than that of hydrocortisone (ID(50)=0.04 micromol/cm(2)).

A new route to the synthesis of pyrazole and pyrimidine C-nucleosides, involving as the key step a metal catalysed reaction of β-D-ribofuranosyl ketoesters with alkyl cyanoformates, is described, 2,3,5-Tri-O-benzoyl-β-D-ribofuranosyl cyanide (1) reacts with α-bromoesters, in the presence of zinc dust, to give β-D-ribofuranosyl-enaminoesters 2 which are easily hydrolised to β-ketoesters 3. The reactions of compounds 3 with alkyl cyanoformates, in the presence of catalytic amounts of [Cu(acac)2], afford C-glycosyl enaminoketosters 4. These compounds react with benzylhydrazine and acetamidine to give pyrazole and pyrimidine C-nucleosides 5 and 6 respectively.

β-Alkoxycarbonyl-β-enaminoketoesters 1a,b react with hydrazines to give pyrazole ortho-dicarboxylic acid derivatives 3, 4 and 5. Similarly 1a reacts with hydroxylamine to give isoxazole 6 and with amidines and guanidine to give pyrimidine ortho-dicarboxylic acid monoesters 7a-c. The total or partial hydrolysis of selected heterocycles afforded the dicarboxylic acids 8, 9 and 10 and the dicarboxylic acid monoesters 11 and 12.

Nickel acetylacetonate effectively catalyses the carbon-carbon bond formation between malononitrile and β-dicarbonyls. In these metal-catalysed reactions malononitrile behaves as an electrophile towards the intercarbonylic carbon, so exhibiting a reverse reactivity compared with that one under basic or thermal conditions. The resulting organic products are β-cyanomethylene-β-enamino dicarbonyls (2a–h), which are obtained in good- to fair yield. β-Iminodicarbonyl complexes of nickel(II) and copper(II), which are likely intermediates in the catalytic cycle, are synthesised by reaction of the metal β-carbonylenolate with malononitrile or of the metal acetate with the catalysis product (2a, d).