D-methionine administered as late as 36 hours post-noise exposure rescues from permanent threshold shift and dose-dependently increases serum antioxidant levels.

Objective: To elucidate D-methionine's (D-met) dose and time rescue parameters from steady-state or impulse noise-induced permanent threshold shift (PTS) and determine D-met rescue's influence on serum and cochlear antioxidant levels.

Design: Five D-met doses at 0, 50, 100, or 200 mg/kg/dose administered starting at 1, 24, or 36 hours post steady-state or impulse noise exposure. Auditory brainstem responses at baseline and 21 days post-noise measured PTS.

D-methionine immediate and continued rescue after noise exposure does not prevent temporary threshold shift but alters cochlear and serum antioxidant levels.

Objective: Determine if D-methionine (D-met) rescue prevents temporary threshold shift (TTS) from steady-state or impulse noise and determine D-met's impact on serum and cochlear antioxidant levels.

Design: D-met at 50, 100 or 200 mg/kg/doses were administered 0, 6 and 18 hours-post noise. ABRs at baseline and 24 hours post-noise measured TTS.

D-methionine (D-met) significantly reduces kanamycin-induced ototoxicity in pigmented guinea pigs.

Objective: Test D-methionine (D-met) as an otoprotectant from kanamycin-induced ototoxicity and determine the lowest maximally protective D-met dose.

Design: Auditory brainstem responses (ABR) were measured at 4, 8, 14, and 20 kHz at baseline and two, four, and six weeks after kanamycin and D-met administration initiation. ABR threshold shifts assessed auditory function.

d-Methionine reduces tobramycin-induced ototoxicity without antimicrobial interference in animal models.

Background: Tobramycin is a critical cystic fibrosis treatment however it causes ototoxicity. This study tested d-methionine protection from tobramycin-induced ototoxicity and potential antimicrobial interference.

Methods: Auditory brainstem responses (ABRs) and outer hair cell (OHC) quantifications measured protection in guinea pigs treated with tobramycin and a range of d-methionine doses.

D-methionine pre-loading reduces both noise-induced permanent threshold shift and outer hair cell loss in the chinchilla.

Objective: This study tested multiple dosing epochs of pre-loaded D-methionine (D-met) for otoprotection from noise-induced hearing loss (NIHL).

Design: Auditory brainstem response (ABR) thresholds were measured at baseline, 1 day, and 21 days following a 6-hour 105 dB sound pressure level (SPL) octave band noise (OBN) exposure. Outer hair cell (OHC) counts were measured after day 21 sacrifice.

A model iridium hydroformylation system with the large bite angle ligand xantphos: reactivity with parahydrogen and implications for hydroformylation catalysis.

Iridium complexes containing the large bite angle bisphosphine ligand xantphos have been synthesized and their reactivity studied. Several of these complexes are the first reported Ir(xantphos) systems to be characterized by X-ray diffraction. Variable-temperature NMR spectroscopic studies of IrI(CO)2(xantphos) (1-I) and Ir(COEt)(CO)2(xantphos) (8) show two separate dynamic processes in which the phosphorus donors and the backbone methyl groups of the xantphos ligand are exchanged.

Highly diastereoselective oxidative addition of methyl iodide to a chiral square-planar complex.

Oxidative addition of methyl iodide to the chiral square-planar complex IrI(CO)(duphos) shows a high level of diastereoselectivity. The basis for the diastereoselectivity of the reaction is best explained based on the crystal structure of IrI(CO)(duphos) in which methyl iodide approach across the two faces is differentiated by the chiral ligand.

Neurofeedback: an alternative and efficacious treatment for Attention Deficit Hyperactivity Disorder.

Current research has shown that neurofeedback, or EEG biofeedback as it is sometimes called, is a viable alternative treatment for Attention Deficit Hyperactivity Disorder (ADHD). The aim of this article is to illustrate current treatment modalities(s), compare them to neurofeedback, and present the benefits of utilizing this method of treatment to control and potentially alleviate the symptoms of ADHD. In addition, this article examines the prevalence rates and possible etiology of ADHD, the factors associated with ADHD and brain dysfunction, the current pharmacological treatments of ADHD, Ritalin, and the potential risks and side effects.

Synthesis of a first-row transition metal parent amido complex and carbon monoxide insertion into the amide N-H bond.

The parent amido iron complex (dmpe)2Fe(H)(NH2) (dmpe = 1,2-bis(dimethylphosphino)ethane), the first such first-row transition metal complex, has been synthesized and characterized spectroscopically and crystallographically. This complex has been found to insert carbon monoxide into the amide N-H bond (rather than the M-N bond) to give trans-(dmpe)2Fe(H)(NHCHO). The mechanism of this transformation has been studied and is believed to occur through an unusual mechanism in which CO behaves as an apparent electrophile.

Formation, reactivity, and properties of nondative late transition metal-oxygen and -nitrogen bonds.

Complexes containing bonds between heteroatoms such as nitrogen and oxygen and "late" transition metals (i.e., those located on the right side of the transition series) have been implicated as reactive intermediates in numerous important catalytic systems.