Background-Exercise training reduces the symptoms of chronic heart failure. Which exercise intensity yields maximal beneficial adaptations is controversial. Furthermore, the incidence of chronic heart failure increases with advanced age; it has been reported that 88% and 49% of patients with a first diagnosis of chronic heart failure are Ͼ65 and Ͼ80 years old, respectively. Despite this, most previous studies have excluded patients with an age Ͼ70 years. Our objective was to compare training programs with moderate versus high exercise intensity with regard to variables associated with cardiovascular function and prognosis in patients with postinfarction heart failure. Methods and Results-Twenty-seven patients with stable postinfarction heart failure who were undergoing optimal medical treatment, including ␤-blockers and angiotensin-converting enzyme inhibitors (aged 75.5Ϯ11.1 years; left ventricular [LV] ejection fraction 29%; V O 2peak 13 mL · kg Ϫ1 · min

Background-Individuals with the metabolic syndrome are 3 times more likely to die of heart disease than healthy counterparts. Exercise training reduces several of the symptoms of the syndrome, but the exercise intensity that yields the maximal beneficial adaptations is in dispute. We compared moderate and high exercise intensity with regard to variables associated with cardiovascular function and prognosis in patients with the metabolic syndrome. Methods and Results-Thirty-two metabolic syndrome patients (age, 52.3Ϯ3.7 years; maximal oxygen uptake [V O 2 max], 34 mL · kg Ϫ1 · min

In humans, the strong statistical association between fitness and survival suggests a link between impaired oxygen metabolism and disease. We hypothesized that artificial selection of rats based on low and high intrinsic exercise capacity would yield models that also contrast for disease risk. After 11 generations, rats with low aerobic capacity scored high on cardiovascular risk factors that constitute the metabolic syndrome. The decrease in aerobic capacity was associated with decreases in the amounts of transcription factors required for mitochondrial biogenesis and in the amounts of oxidative enzymes in skeletal muscle. Impairment of mitochondrial function may link reduced fitness to cardiovascular and metabolic disease.

Seventeen Cu complexes with formal oxidation states ranging from Cu I to Cu III are investigated through the use of multiedge X-ray absorption spectroscopy (XAS) and density functional theory (DFT) calculations. Analysis reveals that the metal−ligand bonding in high-valent, formally Cu III species is extremely covalent, resulting in Cu K-edge and L 2,3-edge spectra whose features have energies that complicate physical oxidation state assignment. Covalency analysis of the Cu L 2,3edge data reveals that all formally Cu III species have significantly diminished Cu d-character in their lowest unoccupied molecular orbitals (LUMOs). DFT calculations provide further validation of the orbital composition analysis, and excellent agreement is found between the calculated and experimental results. The finding that Cu has limited capacity to be oxidized necessitates localization of electron hole character on the supporting ligands; consequently, the physical d 8 description for these formally Cu III species is inaccurate. This study provides an alternative explanation for the competence of formally Cu III species in transformations that are traditionally described as metal-centered, 2-electron Cu I /Cu III redox processes.

Poly(ethylene oxide) (PEO)-based solid electrolytes are expected to be exploited in solid-state batteries with high safety. Its narrow electrochemical window, however, limits the potential for high voltage and high energy density applications. Herein the electrochemical oxidation behavior of PEO and the failure mechanisms of LiCoO 2 -PEO solid-state batteries are studied. It is found that although for pure PEO it starts to oxidize at a voltage of above 3.9 V versus Li/Li + , the decomposition products have appropriate Li + conductivity that unexpectedly form a relatively stable cathode electrolyte interphase (CEI) layer at the PEO and electrode interface. The performance degradation of the LiCoO 2 -PEO battery originates from the strong oxidizing ability of LiCoO 2 after delithiation at high voltages, which accelerates the decomposition of PEO and drives the self-oxygen-release of LiCoO 2 , leading to the unceasing growth of CEI and the destruction of the LiCoO 2 surface. When LiCoO 2 is well coated or a stable cathode LiMn 0.7 Fe 0.3 PO 4 is used, a substantially improved electrochemical performance can be achieved, with 88.6% capacity retention after 50 cycles for Li 1.4 Al 0.4 Ti 1.6 (PO 4 ) 3 coated LiCoO 2 and 90.3% capacity retention after 100 cycles for LiMn 0.7 Fe 0.3 PO 4 . The results suggest that, when paired with stable cathodes, the PEO-based solid polymer electrolytes could be compatible with high voltage operation.

Gram-negative bacteria can communicate with each other by N-acyl homoserine lactones (AHLs), which are quorum-sensing autoinducers. Recently, the aiiA gene (encoding an enzyme catalyzing the degradation of AHL) has been cloned from Bacillus sp. strain 240B1. During investigations in the course of the ongoing Bacillus thuringiensis subsp. morrisoni genome project, an aiiA homologue gene in the genome sequence was found. These results led to consideration of the possibility of the widespread existence of the gene in B. thuringiensis. aiiA homologue genes were found in 16 subspecies of B. thuringiensis, and their sequences were determined. Comparison of the Bacillus sp. strain 240B1 aiiA gene with the B. thuringiensis aiiA homologue genes showed high homologies of 89 to 95% and 90 to 96% in the nucleotide sequence and deduced amino acid sequence, respectively. Among the subspecies of B. thuringiensis having an aiiA gene, the subspecies aizawai, galleriae, kurstaki, kyushuensis, ostriniae, and subtoxicus were shown to degrade AHL. It was observed that recombinant Escherichia coli producing AiiA proteins also had AHL-degrading activity and could also attenuate the plant pathogenicity of Erwinia carotovora. These results indicate that insecticidal B. thuringiensis strains might have potential to compete with gram-negative bacteria in natural ecosystems by autoinducer-degrading activity.

Quorum sensing is a signalling mechanism that controls diverse biological functions, including virulence, via N-acylhomoserine lactone (AHL) signal molecules in Gram-negative bacteria. With the aim of isolating strains or enzymes capable of blocking quorum sensing by inactivating AHL, bacteria were screened for AHL degradation by their ability to utilize N-3-oxohexanoyl-Lhomoserine lactone (OHHL) as the sole carbon source. Among four isolates, strain IBN110, identified as Arthrobacter sp., was found to grow rapidly on OHHL, and to degrade various AHLs with different lengths and acyl side-chain substitutions. Co-culture of Arthrobacter sp. IBN110 and the plant pathogen Erwinia carotovora significantly reduced both the AHL amount and pectate lyase activity in co-culture medium, suggesting the possibility of applying Arthrobacter sp. IBN110 in the control of AHL-producing pathogenic bacteria. The ahlD gene from Arthrobacter sp. IBN110 encoding the enzyme catalysing AHL degradation was cloned, and found to encode a protein of 273 amino acids. A mass spectrometry analysis showed that AhlD probably hydrolyses the lactone ring of N-3-hexanoyl-L-homoserine lactone, indicating that AhlD is an N-acylhomoserine lactonase (AHLase). A comparison of AhlD with other known AHL-degrading enzymes, Bacillus sp. 240B1 AiiA, a Bacillus thuringiensis subsp. kyushuensis AiiA homologue and Agrobacterium tumefaciens AttM, revealed 25, 26 and 21 % overall identities, respectively, in the deduced amino acid sequences. Although these identities were relatively low, the HXDH

Terminal copper-nitrenoid complexes have inspired interest in their fundamental bonding structures as well as their putative intermediacy in catalytic nitrene-transfer reactions. Here, we report that aryl azides react with a copper(I) dinitrogen complex bearing a sterically encumbered dipyrrin ligand to produce terminal copper nitrene complexes with near-linear, short copper–nitrenoid bonds [1.745(2) to 1.759(2) angstroms]. X-ray absorption spectroscopy and quantum chemistry calculations reveal a predominantly triplet nitrene adduct bound to copper(I), as opposed to copper(II) or copper(III) assignments, indicating the absence of a copper−nitrogen multiple-bond character. Employing electron-deficient aryl azides renders the copper nitrene species competent for alkane amination and alkene aziridination, lending further credence to the intermediacy of this species in proposed nitrene-transfer mechanisms.