Antigen-dependent progression of mucosa-associated lymphoid tissue (MALT)-type lymphoma in the stomach. Effects of antimicrobial therapy on gastric MALT lymphoma in mice

In humans, low-grade B-cell mucosa-associated lymphoid tissue (MALT) lymphomas of the stomach regress when Helicobacter pylori infection is cured by antimicrobial therapy. Using an animal model of human gastric MALT lymphoma, we observed the effects of Helicobacter felis eradication and the relationship between infection and disease progression. Antimicrobial therapy was given to one-half of the BALB/c mice infected with H. felis for 20 months. Groups of antibiotic-treated and untreated mice were killed 2, 3, and 4 months after antimicrobial therapy (ie, 22, 23, and 24 months after infection). The numbers of mice with MALT decreased after H. felis eradication with no lymphoid follicles seen 4 months after treatment. MALT lymphoma was present in a total of 23% (11/48) of antibiotic-treated infected mice compared with 75% (27/36) in untreated infected mice. These lymphomas were further graded into low-, intermediate-, and high-grade lymphoma. In the untreated mice, lymphoma development was more advanced with 36% low-grade (13/36), 39% intermediate-grade (14/36), and 6% high-grade (large B-cell) lymphoma (2/36) whereas in the treated mice the incidence was 21% (10/48), 6% (3/48), and 0% (0/48), respectively. These observations suggest that antigenic stimulation by H. felis sustained growth and progression of low-grade MALT lymphoma and that primary high-grade gastric lymphomas can evolve from the transformation of these tumors. Eradication of the organism caused low-grade tumors to regress, with inhibition or slowing down of lymphoma development toward high-grade lymphoma. The H. felis mouse model of gastric MALT lymphoma presents an opportunity to address the issues arising from antimicrobial treatment of these tumors in humans.     

Reduction of NOx by H2 on WOx-Promoted Pt/Al2O3/SiO2 Catalysts Under O2-Rich Conditions

This work addresses the reduction of NO_x by H₂ under O₂-rich conditions using Al₂O₃/SiO₂-supported Pt catalysts with different loads of WO_x promotor. The samples were thoroughly characterised by N₂ physisorption, temperature-programmed desorption of CO, scanning electron microscopy, X-ray diffraction, laser raman spectroscopy, X-ray photoelectron spectroscopy and diffuse reflectance infrared fourier transform spectroscopy with probe molecule CO. The catalytic studies of the samples without WO_x showed pronounced NO_x conversion below 200 °C, whereas highest efficiency was related to small Pt particles. The introduction of WO_x provided increasing deNO_x activity as well as N₂ selectivity. This promoting effect was referred to an additional reaction path at the Pt-WO_x/Al₂O₃/SiO₂ interface, whereas an electronic activation of Pt by strong metal support interaction was excluded.

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Enhancing Civil Engineering Education and ABET Criteria through Practical Experience

The Accreditation Board for Engineering and Technology (ABET) has adopted a revised set of criteria for accrediting engineering programs. Nevertheless, as in the past, civil engineering departments will be required to demonstrate proficiency in specific subject areas which are included in the ABET program criteria. This paper investigates how civil engineering students at Lamar University improved their understanding of various subject areas required by ABET and listed in the Program Criteria for Civil and Similarly Named Engineering Programs and the General Criteria (professional component) by being involved with cooperative, part-time, and summer work experiences. In particular, the findings suggest that both undergraduate and graduate students believe that three areas have been greatly enhanced with engineering work. They include structural engineering, project management/scheduling and estimating, and teamwork. In addition, undergraduates perceive that their understanding of health and safety issues and ethical considerations has also increased. In contrast, graduate students believe that their knowledge of hydraulics, hydrology, and water resources, constructability, and economic factors has been enhanced by civil engineering work experiences.     

Role of Nitric Oxide-Derived Metabolites in Reactions of Methylglyoxal with Lysine and Lysine-Rich Protein Leghemoglobin

Carbonyl stress occurs when reactive carbonyl compounds (RCC), such as reducing sugars, dicarbonyls etc., accumulate in the organism. The interaction of RCC carbonyl groups with amino groups of molecules is called the Maillard reaction. One of the most active RCCs is α-dicarbonyl methylglyoxal (MG) that modifies biomolecules forming non-enzymatic glycation products. Organic free radicals are formed in the reaction between MG and lysine or Nα-acetyllysine. S-nitrosothiols and nitric oxide (^•NO) donor PAPA NONOate increased the yield of organic free radical intermediates, while other ^•NO-derived metabolites, namely, nitroxyl anion and dinitrosyl iron complexes (DNICs) decreased it. At the late stages of the Maillard reaction, S-nitrosoglutathione (GSNO) also inhibited the formation of glycation end products (AGEs). The formation of a new type of DNICs, bound with Maillard reaction products, was found. The results obtained were used to explain the glycation features of legume hemoglobin—leghemoglobin (Lb), which is a lysine-rich protein. In Lb, lysine residues can form fluorescent cross-linked AGEs, and ^•NO-derived metabolites slow down their formation. The knowledge of these processes can be used to increase the stability of Lb. It can help in better understanding the impact of stress factors on legume plants and contribute to the production of recombinant Lb for biotechnology.     

Aurora Kinase A Is Involved in Controlling the Localization of Aquaporin-2 in Renal Principal Cells

The cAMP-dependent aquaporin-2 (AQP2) redistribution from intracellular vesicles into the plasma membrane of renal collecting duct principal cells induces water reabsorption and fine-tunes body water homeostasis. However, the mechanisms controlling the localization of AQP2 are not understood in detail. Using immortalized mouse medullary collecting duct (MCD4) and primary rat inner medullary collecting duct (IMCD) cells as model systems, we here discovered a key regulatory role of Aurora kinase A (AURKA) in the control of AQP2. The AURKA-selective inhibitor Aurora-A inhibitor I and novel derivatives as well as a structurally different inhibitor, Alisertib, prevented the cAMP-induced redistribution of AQP2. Aurora-A inhibitor I led to a depolymerization of actin stress fibers, which serve as tracks for the translocation of AQP2-bearing vesicles to the plasma membrane. The phosphorylation of cofilin-1 (CFL1) inactivates the actin-depolymerizing function of CFL1. Aurora-A inhibitor I decreased the CFL1 phosphorylation, accounting for the removal of the actin stress fibers and the inhibition of the redistribution of AQP2. Surprisingly, Alisertib caused an increase in actin stress fibers and did not affect CFL1 phosphorylation, indicating that AURKA exerts its control over AQP2 through different mechanisms. An involvement of AURKA and CFL1 in the control of the localization of AQP2 was hitherto unknown.     

Conditional Term Graph Rewriting with Indirect Sharing

For reasons of efficiency, term rewriting is usually implemented by term graph rewriting. In term rewriting, expressions are represented as terms, whereas in term graph rewriting these are represented as directed graphs. Unlike terms, graphs allow a sharing of common subexpressions. In previous work, we have shown that conditional term graph rewriting is a sound and complete implementation for a certain class of CTRSs with strict equality, provided that a minimal structure sharing scheme is used. In this paper, we will show that this is also true for two different extensions of normal CTRSs. In contrast to the previous work, however, a non-minimal structure sharing scheme can be used. That is, the amount of sharing is increased.     

A space efficient solution to the frequent string mining problem for many databases

The frequent string mining problem is to find all substrings of a collection of string databases which satisfy database specific minimum and maximum frequency constraints. Our contribution improves the existing linear-time algorithm for this problem in such a way that the peak memory consumption is a constant factor of the size of the largest database of strings. We show how the results for each database can be stored implicitly in space proportional to the size of the database, making it possible to traverse the results in lexicographical order. Furthermore, we present a linear-time algorithm which calculates the intersection of the results of different databases. This algorithm is based on an algorithm to merge two suffix arrays, and our modification allows us to also calculate the LCP table of the resulting suffix array during the merging.     

Costs and Benefits of MBE Rules in Construction

The findings of a study designed to investigate the costs and benefits of Minority Business Enterprise (MBE) regulations in the construction industry are presented. The data indicate that large contractors have less difficulty than smaller organizations in meeting MBE requirements. In addition, it is shown that the regulations both benefit and enlarge the number of minority contractors. According to the study, however, MBE procedures have not increased the number of qualified minority contractors. The data also indicate that MBE regulations have increased the cost of construction projects. The amount allocated, although significant when compared to percentage profit, is not substantial. For example, the unweighted values, in terms of construction dollar volume, range from 3.41% for the Engineering News‐Record (ENR) 400 organizations to 3.33% for the Associated General Contractors of Indiana, AGC (Indiana). The weighted values range from 2.04% for the ENR 400 contractors, to 3.74% for the AGC (Indiana). The great majority of firms surveyed indicate that MBE rules and regulations should be modified. Better agency procurement efforts and comprehensive programs to train minority contractors are mentioned as a necessity.