Transition-Metal-Free Direct C(sp3)-H Functionalization leading to Aza-γ-Carboline Alkaloid Analogues in Cascade Fashion

Iodine promoted cascade reaction has been developed for the synthesis of unrivalled Aza-γ-carboline alkaloid analogues via C-H functionalization of 2H-indazoles. The construction of the product has been realized under metal-free condition via in situ formation of imine, transimination followed by cyclization. In this present method iodine played a triple role, in imine formation, transimination and imine activation. The key features of the present protocol are metal-free, peroxide-free, operational simplicity and wide substrates scope

The Evolution of Satellite III DNA Subfamilies among Primates

We demonstrate that satellite III (SatIII) DNA subfamilies cloned from human acrocentric chromosomes arose in the Hominoidea superfamily. Two groups, distinguished by sequence composition, evolved nonconcurrently, with group 2 evolving 16–23 million years ago (MYA) and the more recent group 1 sequences emerging ∼4.5 MYA. We also show the relative order of emergence of each group 2 subfamily in the various primate species. Our results show that each SatIII subfamily is an independent evolutionary unit, that the rate of evolution is not uniform between species, and that the evolution within a species is not uniform between chromosomes

Kinetics of nitrite reduction and peroxynitrite formation by ferrous heme in human cystathionine β-synthase

Cystathionine β-synthase (CBS) is a pyridoxal phosphate-dependent enzyme that catalyzes the condensation of homocysteine with serine or with cysteine to form cystathionine and either water or hydrogen sulfide, respectively. Human CBS possesses a noncatalytic heme cofactor with cysteine and histidine as ligands, which in its oxidized state is relatively unreactive. Ferric CBS (Fe(III)-CBS) can be reduced by strong chemical and biochemical reductants to Fe(II)-CBS, which can bind carbon monoxide (CO) or nitric oxide (NO·), leading to inactive enzyme. Alternatively, Fe(II)-CBS can be reoxidized by O2 to Fe(III)-CBS, forming superoxide radical anion (O2 -·). In this study, we describe the kinetics of nitrite (NO2·-) reduction by Fe(II)-CBS to form Fe(II)NO·-CBS. The second order rate constant for the reaction of Fe(II)-CBS with nitrite was obtained at low dithionite concentrations. Reoxidation of Fe(II)NO·-CBS by O2 showed complex kinetic behavior and led to peroxynitrite (ONOO-) formation, which was detected using the fluorescent probe, coumarin boronic acid. Thus, in addition to being a potential source of superoxide radical, CBS constitutes a previously unrecognized source of NO· and peroxynitrite

Population distribution analyses reveal a hierarchy of molecular players underlying parallel endocytic pathways.

Single-cell-resolved measurements reveal heterogeneous distributions of clathrin-dependent (CD) and -independent (CLIC/GEEC: CG) endocytic activity in Drosophila cell populations. dsRNA-mediated knockdown of core versus peripheral endocytic machinery induces strong changes in the mean, or subtle changes in the shapes of these distributions, respectively. By quantifying these subtle shape changes for 27 single-cell features which report on endocytic activity and cell morphology, we organize 1072 Drosophila genes into a tree-like hierarchy. We find that tree nodes contain gene sets enriched in functional classes and protein complexes, providing a portrait of core and peripheral control of CD and CG endocytosis. For 470 genes we obtain additional features from separate assays and classify them into early- or late-acting genes of the endocytic pathways. Detailed analyses of specific genes at intermediate levels of the tree suggest that Vacuolar ATPase and lysosomal genes involved in vacuolar biogenesis play an evolutionarily conserved role in CG endocytosis

Evaluation of the quality of transesophageal echocardiography images and verification of proficiency

Various metrics have been used in curriculum-based transesophageal echocardiography (TEE) training programs to evaluate acquisition of proficiency. However, the quality of task completion, that is the final image quality, was subjectively evaluated in these studies. Ideally, the endpoint metric should be an objective comparison of the trainee-acquired image with a reference ideal image. Therefore, we developed a simulator-based methodology of preclinical verification of proficiency (VOP) in trainees by tracking objective evaluation of the final acquired images. We utilized geometric data from the simulator probes to compare image acquisition of anesthesia residents who participated in our structured longitudinal simulator-based TEE educational program vs ideal image planes determined from a panel of experts. Thirty-three participants completed the study (15 experts, 7 postgraduate year (PGY)-1 and 11 PGY-4). The results of our study demonstrated a significant difference in image capture success rates between learners and experts (χ2 = 14.716, df = 2, P < 0.001) with the difference between learners (PGY-1 and PGY-4) not being statistically significant (χ2 = 0, df = 1, P = 1.000). Therefore, our results suggest that novices (i.e. PGY-1 residents) are capable of attaining a level of proficiency comparable to those with modest training (i.e. PGY-4 residents) after completion of a simulation-based training curriculum. However, professionals with years of clinical training (i.e. attending physicians) exhibit a superior mastery of such skills. It is hence feasible to develop a simulator-based VOP program in performance of TEE for junior anesthesia residents

Farmers, Lenders and Water Districts Response to Texas

There are 6.4 million irrigated acres in Texas with 80 percent irrigated from ground water and 20 percent irrigated from surface sources. This is compared to 8.6 million acres irrigated in 1979, a dramatic reduction. Total acre feet of water applied annually is approximately 8.8 million. This is 60-65 percent of all water use in Texas. However, irrigated land contributes about $2.0 billion of output annually which has an economic impact to the state of over$6.0 billion. Thus, irrigation is important to the economy of Texas and particularly to the economic viability of rural communities over much of the state. There was a time when water was plentiful and there were only a limited numbers of users. With urbanization and growth in industry, water has become a limited resource. Continued pumping from the Ogallalla results in a declining water table. Urban demands in many areas have drawn heavily upon available supplies. The importance of water to the continued growth of agriculture, municipal and industrial sectors emphasizes the critical need for efficiency in use. The Texas Legislature enacted a program whereby low interest loans could be made available for the purchase of water conserving (more efficient) irrigation equipment. This was called the "Agricultural Water Conservation Loan Program." The legislation is covered under Texas Administrative Code sections 367.70-367.79 and are promulgated under the authority of the Texas Water Code, sections 6.101 and 17.903

Supplementary material for the article: Wedmann, R.; Onderka, C.; Wei, S.; Szijártó, I. A.; Miljkovic, J. L.; Mitrovic, A.; Lange, M.; Savitsky, S.; Yadav, P. K.; Torregrossa, R.; et al. Improved Tag-Switch Method Reveals That Thioredoxin Acts as Depersulfidase and Controls the Intracellular Levels of Protein Persulfidation. Chemical Science 2016, 7 (5), 3414–3426. https://doi.org/10.1039/c5sc04818d

Supplementary material for: [https://doi.org/10.1039/c5sc04818d]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1925

Human Polycomb 2 Protein Is a SUMO E3 Ligase and Alleviates Substrate-Induced Inhibition of Cystathionine β-Synthase Sumoylation

Human cystathionine β-synthase (CBS) catalyzes the first irreversible step in the transsulfuration pathway and commits homocysteine to the synthesis of cysteine. Mutations in CBS are the most common cause of severe hereditary hyperhomocysteinemia. A yeast two-hybrid approach to screen for proteins that interact with CBS had previously identified several components of the sumoylation pathway and resulted in the demonstration that CBS is a substrate for sumoylation. In this study, we demonstrate that sumoylation of CBS is enhanced in the presence of human polycomb group protein 2 (hPc2), an interacting partner that was identified in the initial yeast two-hybrid screen. When the substrates for CBS, homocysteine and serine for cystathionine generation and homocysteine and cysteine for H2S generation, are added to the sumoylation mixture, they inhibit the sumoylation reaction, but only in the absence of hPc2. Similarly, the product of the CBS reaction, cystathionine, inhibits sumoylation in the absence of hPc2. Sumoylation in turn decreases CBS activity by ∼28% in the absence of hPc2 and by 70% in its presence. Based on these results, we conclude that hPc2 serves as a SUMO E3 ligase for CBS, increasing the efficiency of sumoylation. We also demonstrate that γ-cystathionase, the second enzyme in the transsulfuration pathway is a substrate for sumoylation under in vitro conditions. We speculate that the role of this modification may be for nuclear localization of the cysteine-generating pathway under conditions where nuclear glutathione demand is high