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Background and Purpose Cardiolipin plays an important role in mitochondrial respiration and cardiolipin peroxidation is associated with age-related diseases. Hydrophobic interactions between cytochrome c and cardiolipin converts cytochrome c from an electron carrier to a peroxidase. In addition to cardiolipin peroxidation, this impedes electron flux and inhibits mitochondrial ATP synthesis. SS-31 (D-Arg-dimethylTyr-Lys-Phe-NH2) selectively binds to cardiolipin and inhibits cytochrome c peroxidase activity. Here, we examined whether SS-31 also protected the electron carrier function of cytochrome c. Experimental Approach Interactions of SS-31 with cardiolipin were studied using liposomes and bicelles containing phosphatidylcholine alone or with cardiolipin. Structural interactions were assessed by fluorescence spectroscopy, turbidity and nuclear magnetic resonance. Effects of cardiolipin on electron transfer kinetics of cytochrome c were determined by cytochrome c reduction in vitro and oxygen consumption using mitoplasts, frozen and fresh mitochondria. Key Results SS-31 interacted only with liposomes and bicelles containing cardiolipin in about 1:1 ratio. NMR studies demonstrated that the aromatic residues of SS-31 penetrated deep into cardiolipin-containing bilayers. SS-31 restored cytochrome c reduction and mitochondrial oxygen consumption in the presence of added cardiolipin. In fresh mitochondria, SS-31 increased state 3 respiration and efficiency of ATP synthesis. Conclusions and Implications SS-31 selectively targeted cardiolipin and modulated its interaction with cytochrome c. SS-31 inhibited the cytochrome c/cardiolipin complex peroxidase activity while protecting its ability to serve as an electron carrier, thus optimizing mitochondrial electron transport and ATP synthesis. This novel class of cardiolipin therapeutics has the potential to restore mitochondrial bioenergetics for treatment of numerous age-related diseases. Linked Articles This article is part of a themed issue on Mitochondrial Pharmacology: Energy, Injury & Beyond. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2014.171.issue-8

The length of a vocal tract is reflected in the sound it is producing. The length of the vocal tract is correlated with body size and humans are very good at making size judgments based on the acoustic effect of vocal tract length only. Here we investigate the underlying mechanism for processing this main auditory cue to size information in the human brain. Sensory encoding of the acoustic effect of vocal tract length (VTL) depends on a time-stabilized spectral scaling mechanism that is independent of glottal pulse rate (GPR, or voice pitch); we provide evidence that a potential neural correlate for such a mechanism exists in the medial geniculate body (MGB). The perception of the acoustic effect of speaker size is influenced by GPR suggesting an interaction between VTL and GPR processing; such an interaction occurs only at the level of non-primary auditory cortex in planum temporale and anterior superior temporal gyrus. Our findings support a two-stage model for the processing of size information in speech based on an initial stage of sensory analysis as early as MGB, and a neural correlate of the perception of source size in non-primary auditory cortex.

Cardiolipin plays an important role in mitochondrial respiration and cardiolipin peroxidation is associated with age-related diseases. Hydrophobic interactions between cytochrome c and cardiolipin converts cytochrome c from an electron carrier to a peroxidase. In addition to cardiolipin peroxidation, this impedes electron flux and inhibits mitochondrial ATP synthesis. SS-31 (D-Arg-dimethylTyr-Lys-Phe-NH2 ) selectively binds to cardiolipin and inhibits cytochrome c peroxidase activity. Here, we examined whether SS-31 also protected the electron carrier function of cytochrome c.Interactions of SS-31 with cardiolipin were studied using liposomes and bicelles containing phosphatidylcholine alone or with cardiolipin. Structural interactions were assessed by fluorescence spectroscopy, turbidity and nuclear magnetic resonance. Effects of cardiolipin on electron transfer kinetics of cytochrome c were determined by cytochrome c reduction in vitro and oxygen consumption using mitoplasts, frozen and fresh mitochondria.SS-31 interacted only with liposomes and bicelles containing cardiolipin in about 1:1 ratio. NMR studies demonstrated that the aromatic residues of SS-31 penetrated deep into cardiolipin-containing bilayers. SS-31 restored cytochrome c reduction and mitochondrial oxygen consumption in the presence of added cardiolipin. In fresh mitochondria, SS-31 increased state 3 respiration and efficiency of ATP synthesis.SS-31 selectively targeted cardiolipin and modulated its interaction with cytochrome c. SS-31 inhibited the cytochrome c/cardiolipin complex peroxidase activity while protecting its ability to serve as an electron carrier, thus optimizing mitochondrial electron transport and ATP synthesis. This novel class of cardiolipin therapeutics has the potential to restore mitochondrial bioenergetics for treatment of numerous age-related diseases.

Significant yield increases of sugarcane and rice have been observed in the Everglades Agricultural Area of Florida from application of soluble silicon as calcium silicate slag. Although calcium silicate slag contains trace quantities of P, significant quantities of P can be applied using commercial rates of slag. This may be of concern to both the agronomists responsible for determining P fertilization rates for these crops and to land managers attempting to limit the application of P in this region. The objective of our research was to determine the biological availability of P applied as calcium silicate slag. Two sugarcane studies and two rice studies were conducted on a Terra Ceia muck (Euic, hyperthermic Typic Medisaprist), Pahokee muck (Euic, hyperthermic Lithic Medisaprist), and a Okeelanta muck (sandy or sandy‐skeletal, siliceous, euic hyperthermic Terric Medisaprist) at five locations for one to three years each. Calcium silicate slag was applied at rates ranging from 0 to 20 Mg ha‐1. F...

The cortical silent period has not previously been studied in tetanus. Transcranial magnetic brain stimulation in a patient with generalized tetanus revealed enlarged electromyographic (EMG) responses and absence or reduction of the late phase of EMG silence following the motor evoked potential in sternomastoid and biceps brachii muscles. Following clinical recovery, the silent period returned to normal. This observation is interpreted as evidence of impaired inhibitory mechanisms at multiple levels of the nervous system, including the cortex, in generalized tetanus.

Semantic dementia (SD) is a unique syndrome in the frontotemporal lobar degeneration spectrum. Typically presenting as a progressive, fluent anomic aphasia, SD is the paradigmatic disorder of semantic memory with a characteristic anatomical profile of asymmetric, selective antero-inferior temporal lobe atrophy. Histopathologically, most cases show a specific pattern of abnormal deposition of protein TDP-43. This relatively close clinical, anatomical and pathological correspondence suggests SD as a promising target for future therapeutic trials. However, rational drug design and monitoring is likely to require a comprehensive understanding of how the molecular insult in SD translates to a clinico-anatomical phenotype. Here we propose a pathophysiological model of SD. The model is motivated by neuropsychological and neuroimaging data and posits the sequential, regionally determined disintegration of a vulnerable neural network. The key features of the model are: (1) existence of local zones of synaptic convergence within the temporal lobe with predictable network organisation; (2) a mechanism (or mechanisms) for transynaptic action of the molecular insult; and (3) establishment of a gradient of neuronal damage across the affected network, both within and between the temporal lobes. The model makes empirically testable predictions concerning the evolution of regional atrophy in SD.

Successful organ transplantation depends on adequate preservation of cellular function. We tested the effect of four commonly used donor organ preservation fluids on the ability of cultured bovine pulmonary artery endothelial cells to release endothelium-derived relaxing factor (EDRF). Columns of endothelial cells grown on microcarrier beads were exposed to either University of Wisconsin (Belzer's) solution, Marshall's preservation fluid, Euro-Collins solution, or a blood-based preservation fluid at 4 degrees C for 6 hours, and then to Krebs-Henseleit buffer at 37 degrees C for 1 hour. They were then stimulated with boluses of bradykinin, and the EDRF released was detected by bioassay. The release of EDRF from endothelial cells previously exposed to a preservation fluid was compared with the release of EDRF from control columns of cells perfused throughout at 37 degrees C with Krebs-Henseleit buffer. Previous exposure to any of the three non-blood-based preservation fluids did not attenuate bradykinin-stimulated EDRF release. By contrast, previous perfusion with the blood-based solution completely inhibited EDRF release (p less than 0.01, ANOVA), an effect attributable to the acidity of the solution. Donor organ preservation fluids differ in their effect on endothelial cell function, and this has important implications for lung and for other organ transplantation.

1. To investigate the morphology and physiology of vertical medium-lead burst neurons with downward on-directions (DMLBs), we impaled midbrain axons and recorded their discharge patterns in relation to spontaneous saccades of alert, behaving squirrel monkeys. Selected axons were injected with horseradish peroxidase and morphologically characterized. 2. DMLBs emitted bursts of impulses that preceded rapid eye movements by approximately 5 ms. Parameters of the burst (duration and number of spikes) were highly correlated with parameters of the saccadic eye movement (duration and amplitude of the downward displacement of the eyes). 3. Somata of DMLBs were recovered in the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF, n = 14), and in the interstitial nucleus of Cajal (NIC, n = 2). Fibers originating from riMLF DMLBs projected, usually ipsilaterally, to the NIC as well as in the inferior rectus and the superior oblique subdivisions of the oculomotor complex. The axons of NIC DMLBs projected to the ipsilateral riMLF, NIC, and the mesencephalic reticular formation but not to the oculomotor complex. 4. Our data demonstrate that some DMLBs can provide extraocular motoneurons of both eyes with the pulse of activity they display during downward saccades. In addition, such neurons can supply the NIC with one of the signals that this nucleus is thought to integrate to extract an estimate of the vertical eye position. Finally, our data demonstrate the existence of DMLBs that do not establish direct connections with oculomotoneurons.

An atomic absorption Spectrophotometric (AAS) method for determining chelated iron in iron chelate concentrates was collaboratively studied by 13 laboratories. Nonchelated iron was selectively precipitated as ferric hydroxide from an aqueous solution of the sample by adjusting to pH 8.5 with sodium hydroxide. A filtered portion of the sample solution was diluted with 0.5N HC1, and the iron was determined by AAS using standards containing disodium EDTA. Six pairs of iron chelate materials (12 samples) were analyzed and the average coefficients of variation were iron EDTA 3.52%, iron HEDTA 4.16%, iron DTPA 3.55%, iron EDDHA 3.52%, iron citrate 2.86%, and iron DPS 8.47%. The method has been adopted official first action.

9,10-Anthracenedicarboxaldehyde bis[(4,5-dihydro-1H-imidazol-2-yl)hydrazone] (bisantrene, VI-1) showed anticancer activity in mice vs. both leukemias and solid tumors. Increases in life span vs. the following neoplasms were: P-388 leukemia, 137%; B-16 melanoma, 122%; Lieberman plasma cell tumor, greater than 85%; colon tumor 26, 150%; Ridgway osteogenic sarcoma, 85%. There were significant numbers of long-term survivors. Both DNA and RNA synthesis were strongly inhibited. The drug was resistant to biodegradation and was bound strongly to tissues; in monkeys the half-life for disappearance from serum was 6 days. Related hydrazones were synthesized, and structure-activity relationships are discussed. Two routes to ring-substituted anthracene-9,10-dicarboxaldehyde intermediates were developed.

A rapid method is described for extraction and cleanup of raw and processed milk for determination of anatoxins M1 and M2 by using a C18 Sep-Pak/silica gel cleanup column combination. Anatoxins are separated by normal phase liquid chromatography and their concentrations are determined by fluorescence detection in a silica gel-packed flow cell. Recoveries ranged from 99 to 103% with coefficients of variation less than 2% for Mi levels of 0.117-1.17 ng/mL added to raw milk. Similar recoveries were obtained for M2. The coefficient of variation for analysis of 5 subsamples of naturally contaminated milk was Jess than 1%. Agreement with the official method is satisfactory. Each sample requires less than 25 mL solvent and 10 min actual handling time. Sample chromatograms show no interferences in the M1-M2 elution region and no late-eluting peaks, which permits spacing injections at 13-20 min intervals. Anatoxin levels as low as 0.03 ppb may be determined by this procedure. Extracts have also been analyzed by thin layer chromatography.

A rapid method is described for extraction and cleanup of raw and processed milk for determination of aflatoxins M1 and M2 by using a C18 Sep-Pak/silica gel cleanup column combination. Aflatoxins are separated by normal phase liquid chromatography and their concentrations are determined by fluorescence detection in a silica gel-packed flow cell. Recoveries ranged from 99 to 103% with coefficients of variation less than 2% for M1 levels of 0.117-1.17 ng/mL added to raw milk. Similar recoveries were obtained for M2. The coefficient of variation for analysis of 5 subsamples of naturally contaminated milk was less than 1%. Agreement with the official method is satisfactory. Each sample requires less than 25 mL solvent and 10 min actual handling time. Sample chromatograms show no interferences in the M1-M2 elution region and no late-eluting peaks, which permits spacing injections at 13-20 min intervals. Aflatoxin levels as low as 0.03 ppb may be determined by this procedure. Extracts have also been analyzed by thin layer chromatography.

9,10-Anthracenedicarboxaldehyde bis[(4,5-dihydro-1H-imidazol-2-yl)hydrazone] (bisantrene, VI-1) showed anticancer activity in mice vs. both leukemias and solid tumors. Increases in life span vs. the following neoplasms were: P-388 leukemia, 137%; B-16 melanoma, 122%; Lieberman plasma cell tumor, greater than 85%; colon tumor 26, 150%; Ridgway osteogenic sarcoma, 85%. There were significant numbers of long-term survivors. Both DNA and RNA synthesis were strongly inhibited. The drug was resistant to biodegradation and was bound strongly to tissues; in monkeys the half-life for disappearance from serum was 6 days. Related hydrazones were synthesized, and structure-activity relationships are discussed. Two routes to ring-substituted anthracene-9,10-dicarboxaldehyde intermediates were developed.