Selective Deamidation and Enzymatic Methylation of Seminal Ribonuclease

Isoenzymatic forms alfa2, alfa-beta, and beta2 of bovine seminal ribonuclease are generated by the transformation of beta-type into alfa-type subunit through deamidation of a single amide group. The residue involved in this selective deamidation has been identified as Asn67 . Deamidation occurs by formation of a cyclic imide intermediate involving the Gly at position 68. Opening of the cyclic imide may occur on either side of the nitrogen, generating both the normal alfa-aspartyl and an isoaspartyl residue at position 67. The alfa-carboxyl of the isoaspartyl residue is effectively methylated by bovine brain protein carboxylmethyltransferase

The biofilm matrix of Pseudomonas sp. OX1 grown on phenol is mainly constituted by alginate oligosaccharides

The structure of the major constituent of the biofilm matrix produced by Pseudomonas sp. OX1, when grown on phenol as the sole carbon source is described. This investigation, carried out by chemical analysis, NMR spectroscopy and MALDI-TOF MS spectrometry, showed the presence of an oligosaccharide blend with the typical alginate structure, namely (1-->4) substituted beta-D-mannuronic (ManA) and alpha-L-guluronic acid (GulA). GulA residues were non-acetylated whereas ManA was always O-acetylated at C-2 or C-3

Local anaesthesia efficacy as postoperative analgesia for open shoulder instability surgery. a prospective randomised controlled study

Background and objectives: The aim of present study was to evaluate for the first time, the clinical effect of local anaesthetic infiltration as postoperative analgesia in open shoulder surgery for anterior-inferior instability. The comparison of the local infiltration and interscalenic brachial plexus block to a control group test the local anaesthetic efficacy in this surgery. Methods: 78 patients scheduled for open shoulder surgery were enrolled and randomly assigned to one of three groups: local infiltration anaesthesia (LIA), interscalenic brachial plexus block (IBPB) and control (C). All patients received standardized general anaesthesia and all injections were performed with the same dose and volume of anaesthetic. The number boluses delivered by a PCA pump applied at the end of surgery and the visual analogue score (VAS) at 0, 2, 4, 6, 12, 18 and 24 hours after intervention were recorded. A patient satisfaction score was also assessed. Results: Mean bolus consumption of the rescue analgesic, compared to C, was significantly less both in the LIA and IBPB groups (P<0.05). The IBPB group showed VAS scores that were significantly better than C group at all time points (P<0.05). The VAS scores for LIA group were clinically comparable to IBPB, and only at the 2 and 6 hours, postoperative time points there were no significant differences found in respect to the C group. IBPB and LIA showed comparable patient satisfaction scores. Conclusion: The local anaesthetic infiltration as postoperative analgesia appears to be a clinically valid alternative, statistically comparable to IBPB, with no clinical meaningful adverse effects

THE IMPORTANCE OF DYNAMIC EFFECTS ON THE ENZYME ACTIVITY: X-RAY STRUCTURE AND MOLECULAR DYNAMICS OF ONCONASE MUTANTS.

Onconase (ONC), a member of the RNase A superfamily extracted from oocytes of Rana pipiens, is an effective cancer killer. It is currently used in treatment of various forms of cancer. ONC antitumor properties depend on its ribonucleolytic activity that is low in comparison with other members of the superfamily. The most damaging side effect from Onconase treatment is renal toxicity, which seems to be caused by the unusual stability of the enzyme. Therefore, mutants with reduced thermal stability and/or increased catalytic activity may have significant implications for human cancer chemotherapy. In this context, we have determined the crystal structures of two Onconase mutants (M23L-ONC and C87S,des103-104-ONC) and performed molecular dynamic simulations of ONC and C87S,des103-104-ONC with the aim of explaining on structural grounds the modifications of the activity and thermal stability of the mutants. The results also provide the molecular bases to explain the lower catalytic activity of Onconase compared with RNase A and the unusually high thermal stability of the amphibian enzyme

The Role of the Conserved Residues His-246, His-199, and Tyr-255 in the Catalysis of Catechol 2,3-Dioxygenase from Pseudomonas stutzeri OX1

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Ultrafast processes triggered by one- and two-photon excitation of a photochromic and luminescent hydrazone

In this work we apply a combination of steady state and time resolved luminescence and absorption spectroscopies to investigate the excited-state dynamics of a recently developed molecular photoswitch, belonging to the hydrazone family. The outstanding properties of this molecule, involving fluorescence toggling, bistability, high isomerization quantum yield and non-negligible two-photon absorption cross section, make it very promising for numerous applications. Here we show that the light induced Z/E isomerization occurs on a fast &lt;1 ps timescale in both toluene and acetonitrile, while the excited state lifetime of the Z-form depends on solvent polarity, suggesting a partial charge transfer nature of its low lying excited state. Time-resolved luminescence measurements evidence the presence of a main emission component in the 500\u2013520 nm spectral range, attributed to the Z-isomer, and a very short living blue-shifted emission, attributed to the E-isomer. Finally, transient absorption measurements performed upon far-red excitation are employed as an alternative method to determine the two-photon absorption cross-section of the molecule

Outcomes and indications for Emergency Thoracotomy after adoption of a more liberal policy in a western European level 1 Trauma Center: 8-years experience.

Background: The role of Emergency Thoracotomy (ET) in blunt trauma is still a matter of debate and in Europe only small studies have been published. We report our experience about ET both in penetrating and blunt trauma, discussing indications, outcomes and proposing an algorithm for patient selection. Materials and methods: We retrospectively analysed patients who underwent ET at Maggiore Hospital Trauma Center over two periods: from January 1st, 2010 to December 31st, 2012, and from January 1st, 2013 to May 31st, 2017. Demographic and clinical data, mechanism of injury, Injury Severity Score, site of injury, time of witnessed cardiac arrest, presence/absence of signs of life, length of stay, were considered, as well as survival rate and neurological outcome. Results: 27 ETs were performed; 21 after blunt trauma and six after penetrating trauma. Motor vehicle accident was the main mechanism of injury, followed by fall from height. The mean age was 40,5 years and the median Injury Severity Score was of 40. The most frequent injury was cardiac tamponade. The overall survival rate was 10% during the first period and 23.5% during the second period, after the adoption of a more liberal policy. No long term neurological sequelae were reported. Conclusions: The outcomes of ET in trauma patient, either after penetrating or blunt trauma, are poor but not negligible. To date, only small series of ET from European trauma centers have been published, although larger series are available from USA and South Africa. However, in selected patients, all efforts must be made for the patient's survival; the possibility of organ donation should be taken into consideration as well

Electrolyte Measures to Prevent Polysulfide Shuttle in Lithium‐Sulfur Batteries

Lithium-sulfur (Li−S) batteries are recognized as one of the most promising technologies with the potential to become the next-generation batteries. However, to ensure Li−S batteries reach commercialization, complex challenges remain, among which the tailoring of an appropriate electrolyte is the most important. This review discusses the role of electrolytes in Li−S batteries, focusing on the main issues and solutions for the shuttle mechanism of polysulfides and the instability of the interface with lithium metal. Herein, we present a background on Li−S chemistry followed by the state-of-the-art electrolytes highlighting the different strategies undertaken with liquid and solid electrolytes