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关键词： Omega-3 fatty acids   Coronavirus   Kidney function   Respiratory function   POLYUNSATURATED FATTY-ACIDS   PARENTERAL FISH-OIL   DOCOSAHEXAENOIC ACID   DIETARY OMEGA-3   SURVIVAL   MICROCIRCULATION   DYSFUNCTION   MORTALITY   INJURY  

摘要： Background: Omega-3 polyunsaturated fatty acids (n3-PUFAs) may exert beneficial effects on the immune system of patients with viral infections. This paper aimed to examine the effect of n3-PUFA supplementation on inflammatory and biochemical markers in critically ill patients with COVID-19. Methods: A double-blind, randomized clinical trial study was conducted on 128 critically ill patients infected with COVID-19 who were randomly assigned to the intervention (fortified formula with n3-PUFA) (n = 42) and control (n = 86) groups. Data on 1 month survival rate, blood glucose, sodium (Na), potassium (K), blood urea nitrogen (BUN), creatinine (Cr), albumin, hematocrit (HCT), calcium (Ca), phosphorus (P), mean arterial pressure (MAP), O-2 saturation (O(2)sat), arterial pH, partial pressure of oxygen (PO2), partial pressure of carbon dioxide (PCO2), bicarbonate (HCO3), base excess (Be), white blood cells (WBCs), Glasgow Coma Scale (GCS), hemoglobin (Hb), platelet (Plt), and the partial thromboplastin time (PTT) were collected at baseline and after 14 days of the intervention. Results: The intervention group had significantly higher 1-month survival rate and higher levels of arterial pH, HCO3, and Be and lower levels of BUN, Cr, and K compared with the control group after intervention (all P <0.05). There were no significant differences between blood glucose, Na, HCT, Ca, P, MAP, O2sat, PO2, PCO2, WBCs, GCS, Hb, Plt, PTT, and albumin between two groups. Conclusion: Omega-3 supplementation improved the levels of several parameters of respiratory and renal function in critically ill patients with COVID-19. Further clinical studies are warranted.

关键词： CYTOCHROME CD(1) NITRITE   ELECTROCATALYTIC CO2 REDUCTION   COUPLED ELECTRON-TRANSFER   HYDROGEN EVOLUTION REACTION   FORMATE DEHYDROGENASE-H   PI-CATION RADICALS   ACTIVE-SITE MODELS   FE-ONLY HYDROGENASE   DESULFOVIBRIO-DESULFURICANS ATCC-27774   DIIRON AZADITHIOLATE COMPLEXES  

摘要： Reduction of oxides and oxoanions of carbon and nitrogen are of great contemporary importance as they are crucial for a sustainable environment. Substantial research has been dedicated to these areas in the last few decades. These reductions require both electrons and protons and their thermodynamic potentials often make them compete with hydrogen evolution reaction i.e., the reaction of protons and electrons to generate H-2. These reactions are abundant in the environment in microorganisms and are facilitated by naturally occurring enzymes. This review brings together the state-of-the-art knowledge in the area of enzymatic reduction of CO2, NO2- and H+ with those of artificial molecular electrocatalysis. A simple ligand field theory-based design principle for electrocatalysts is first described. The electronic structure considerations developed automatically yield the basic geometry required and the 2(nd) sphere interactions which can potentially aid the activation and the further reduction of these small molecules. A systematic review of the enzymatic reaction followed by those reported in artificial molecular electrocatalysts is presented for the reduction of CO2, NO2- and H+. The review is focused on mechanism of action of these metalloenzymes and artificial electrocatalysts and discusses general principles that guide the rates and product selectivity of these reactions. The importance of the 2(nd) sphere interactions in both enzymatic and artificial molecular catalysis is discussed in detail.

关键词： Staphylococcus aureus   RNA polymerase   delta subunit   beta ' jaw   Interaction interface  

摘要： A large class of bacterial RNA polymerase (RNAP) from low-G+C-content Gram-positive bacterial strains, such as the major human pathogen Staphylococcus aureus, not only contain five conserved subunits (a(I), a(II), beta, beta' and u), but also has a delta subunit. Despite being first identified as unique, Grampositive specific component of RNAP apoenzyme more than 30 years ago and reported to be essential for transcription, the structural basis and molecular mechanism of delta subunit in the regulation of transcription remain poorly understood. Here, we performed structural analyses, site-directed mutagenesis and biochemical assays to uncover the interactions of S. aureus d subunit with RNAP core enzyme and DNA towards the understanding of its role in transcription regulation. Microscale thermophoresis (MST) and electrophoretic mobility shift assay (EMSA) of the wild-type and mutated S. aureus d subunit revealed the N-terminal domain of d subunit directly binds to the beta' jaw of S. aureus RNAP (SauRNAP), identified the key amino acid residues (F58, D61, D65, R67 and W81) of d subunit involving in the binding with SauRNAP core enzyme, and uncovered the d subunit C-terminal domain interferes with the interaction between DNA and SauRNAP core enzyme, by which transcription is regulated. Our results provide an excellent starting point for understanding the unique regulatory role and physiological function of d subunit on transcription regulation in Gram-positive bacteria. (C) 2021 Elsevier Inc. All rights reserved.

关键词： RETINOIC ACID   IN-VITRO   CLEAVAGE   ENZYME   EXPRESSION   PROVITAMIN   VITAMIN   FERRET  

摘要： In mammals, carotenoids are converted by two carotenoid cleavage oxygenases into apocarotenoids, including vitamin A. Although knowledge about beta-carotene oxygenase-1 (BCO1) and vitamin A metabolism has tremendously increased, the function of beta-carotene oxygenase-2 (BCO2) remains less well-defined. We here studied the role of BCO2 in the metabolism of long chain beta-apocarotenoids, which recently emerged as putative regulatory molecules in mammalian biology. We showed that recombinant murine BCO2 converted the alcohol, aldehyde, and carboxylic acid of a beta-apocarotenoid substrate by oxidative deavage at position C9,C10 into a beta-ionone and a diapocarotenoid product. Chain length variation (C20 to C40) and ionone ring site modifications of the apocarotenoid substrate did not impede catalytic activity or alter the regioselectivity of the double bond cleavage by BCO2. Isotope labeling experiments revealed that the double bond cleavage of an apocarotenoid followed a dioxygenase reaction mechanism. Structural modeling and site directed mutagenesis identified amino acid residues in the substrate tunnel of BCO2 that are critical for apocarotenoid binding and catalytic processing. Mice deficient for BCO2 accumulated apocarotenoids in their livers, indicating that the enzyme engages in apocarotenoid metabolism. Together, our study provides novel structural and functional insights into BCO2 catalysis and establishes the enzyme as a key component of apocarotenoid homeostasis in mice.

关键词： Pumpkin   Osborne method   Protein isolate   Essential amino acids nutritional properties   Functional properties   FOOD   SOLUBILITY   DIGESTIBILITY   OPTIMIZATION   EXTRACTION   QUALITY  

摘要： Pumpkin seeds are rich source of nutritionally well-balanced proteins. The biochemical, nutritional, and functional properties of the protein isolate (PPI) and protein fractions from pumpkin seed were evaluated. Extraction method for PPI was optimized by varying NaCl (0, 0.5, 1 M) and flour-to-solution ratio (1:5, 1:10, 1:25), at pH 9.0. Proteins were extracted by Osborne procedure and the alkali fraction (AF, 45.82%) was found to be the predominant fraction. SDS-PAGE profile of PPI revealed major bands ranging from 50 to 7 kDa. AF contained all the essential amino acids (EAA) except lysine and threonine, as required by pre-school children (FAO/WHO). PPI and AF showed better protein efficiency ratio and EAA/TAA (total) %, indicating the presence of good quality proteins. Functional properties were found to be comparable with soybean protein isolate. Circular dichroism studies showed that water fraction comprised of alpha-helix and random coils, while salt and alkali fractions contained beta-strand and coils.