Gasoline prices and their relationship to drunk-driving crashes

This study investigates the relationship between changing gasoline prices and drunk-driving crashes. Specifically, we examine the effects of gasoline prices on drunk-driving crashes in Mississippi by several crash types and demographic groups at the monthly level from 2004 to 2008, a period experiencing great fluctuation in gasoline prices. An exploratory visualization by graphs shows that higher gasoline prices are generally associated with fewer drunk-driving crashes. Higher gasoline prices depress drunk-driving crashes among young and adult drivers, among male and female drivers, and among white and black drivers. Results from negative binomial regression models show that when gas prices are higher, there are fewer drunk-driving crashes, particularly among property-damage-only crashes. When alcohol consumption levels are higher, there are more drunk-driving crashes, particularly fatal and injury crashes. The effects of gasoline prices and alcohol consumption are stronger on drunk-driving crashes than on all crashes. The findings do not vary much across different demographic groups. Overall, gasoline prices have greater effects on less severe crashes and alcohol consumption has greater effects on more severe crashes.     

Determining the effects of antioxidants on oxidative stress induced carbonylation of proteins

There is potential that the pathological effects of oxidative stress (OS) associated diseases such as diabetes could be ameliorated with antioxidants, but this will require a clearer understanding of the pathway(s) by which proteins are damaged by OS. This study reports the development and use of methods that assess the efficacy of dietary antioxidant supplementation at a mechanistic level. Data reported here evaluate the impact of green tea supplementation on oxidative stress induced post-translational modifications (OSi-PTMs) in plasma proteins of Zucker diabetic fatty (ZDF) rats. The mechanism of antioxidant protection was examined through both the type and amount of OSi-PTMs using mass spectrometry based identification and quantification. Carbonylated proteins in freshly drawn blood samples were derivatized with biotin hydrazide. Proteins thus biotinylated were selected from plasma samples of green tea fed diabetic rats and control animals by avidin affinity chromatography, further fractionated by reversed phase chromatography (RPC); fractions from the RPC column were tryptic digested, and the tryptic digest was fractionated by RPC before being identified by tandem mass spectrometry (MS/MS). Relative quantification of peptides bearing carbonylation sites was achieved for the first time by RPC-MS/MS using selective reaction monitoring (SRM). Seventeen carbonylated peptides were detected and quantified in both control and treated plasma. The relative concentration of eight was dramatically different between control and green tea treated animals. Seven of the OSi-PTM bearing peptides had dropped dramatically in concentration with treatment while one increased, indicating differential regulation of carbonylation by antioxidants. Green tea antioxidants were found to reduce carbonylation of proteins by lipid peroxidation end products most, followed by advanced glycation end products to a slightly lower extent. Direct oxidation of proteins by reactive oxygen species (ROS) was protected the least by green tea.     

Nano-LC-MS/MS of glycopeptides produced by nonspecific proteolysis enables rapid and extensive site-specific glycosylation determination

Given the biological importance of glycosylation on proteins, the identification of protein glycosylation sites is integral to understanding broader biological structure and function. Unfortunately, the determination of the microheterogeneity at the site of glycosylation still remains a significant challenge. Nanoflow liquid chromatography with tandem mass spectrometry provides both separation of glycopeptides and the ability to determine glycan composition and site-specific glycosylation. However, because of the size of glycopeptides, they are not often amenable to tandem MS. In this work, proteins are digested with multiple proteases to produce glycopeptides that are of suitable size for tandem MS analysis. The conditions for collision-induced dissociation are optimized to obtain diagnostic ions that maximize glycan and peptide information. The method is applied to glycoproteins with contrasting glycans and multiple sites of glycosylation and identifies multiple glycan compositions at each individual glycosylation site. This method provides an important improvement in the routine determination of glycan microheterogeneity by mass spectrometry.     

Comparison between thiosulphate-citrate-bile salt sucrose (TCBS) agar and CHROMagar Vibrio for isolating Vibrio parahaemolyticus

Considering its widespread distribution in marine environments, its fast replication times and low infectious doses and the rapid spread of its strains in recent years, intensive and continuous monitoring of potentially pathogenic Vibrio parahaemolyticus is strongly recommended in order to assess the human health risk arising from shellfish consumption. The lack of epidemiological data points to the need to develop specific methods for detecting V. parahaemolyticus. In this note, the authors compare two plating media currently available for isolating V. parahaemolyticus in shellfish. Both approaches involve pre-enrichment of V. parahaemolyticus. One uses thiosulphate-citrate-bile salt sucrose (TCBS) as the isolation medium, while the other uses a chromogenic medium (CHROMagar Vibrio). Next, biochemical identification of isolates was performed with API 20E, followed by PCR assay aimed at the toxR gene to confirm the cultural and biochemical identification. Comparison of the two methods highlighted that CHROMagar Vibrio is more accurate and specific than TCBS. The analysis of data from 160 shellfish samples showed an accuracy and specificity of just 51% and 71% for TCBS compared with 88% and 95% for CAV.     

Nitric oxide stimulates human sperm motility via activation of the cyclic GMP/protein kinase G signaling pathway

Nitric oxide (NO), a modulator of several physiological processes, is involved in different human sperm functions. We have investigated whether NO may stimulate the motility of human spermatozoa via activation of the soluble guanylate cyclase (sGC)/cGMP pathway. Sperm samples obtained by masturbation from 70 normozoospermic patients were processed by the swim-up technique. The kinetic parameters of the motile sperm-rich fractions were assessed by computer-assisted sperm analysis. After a 30-90 min incubation, the NO donor S-nitrosoglutathione (GSNO) exerted a significant enhancing effect on progressive motility (77, 78, and 78% vs 66, 65, and 62% of the control at the corresponding time), straight linear velocity (44, 49, and 48?μm/s vs 34, 35, and 35.5?μm/s), curvilinear velocity (81, 83, and 84?μm/s vs 68?μm/s), and average path velocity (52, 57, and 54?μm/s vs 40, 42, and 42?μm/s) at 5?μM but not at lower concentrations, and in parallel increased the synthesis of cGMP. A similar effect was obtained with the NO donor spermine NONOate after 30 and 60 min. The GSNO-induced effects on sperm motility were abolished by 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (a specific sGC inhibitor) and mimicked by 8-bromo-cGMP (8-Br-cGMP; a cell-permeating cGMP analog); the treatment with Rp-8-Br-cGMPS (an inhibitor of cGMP-dependent protein kinases) prevented both the GSNO- and the 8-Br-cGMP-induced responses. On the contrary, we did not observe any effect of the cGMP/PRKG1 (PKG) pathway modulators on the onset of hyperactivated sperm motility. Our results suggest that NO stimulates human sperm motility via the activation of sGC, the subsequent synthesis of cGMP, and the activation of cGMP-dependent protein kinases.     

Chlorophylls in olive and in olive oil: chemistry and occurrences

The chlorophylls are responsible for the characteristic green color of the olive fruits and their products. Virgin olive oil (VOO) is obtained from processing olives only by mechanical and physical means under conditions ensuring that the natural characteristics of the fruit composition are maintained as far as possible. In terms of the total chlorophyll content of oil, the extraction process entails a loss of chlorophyll of up to 80%. Many factors, both agronomical and technological, can affect the presence of green pigments in VOO. The analysis of green pigments in olives and/or oil requires an initial phase of extraction of these compounds from the solid and fluid matrix, followed by the selective separation and subsequent identification of the different components of the chlorophyll fraction. The aim of this review article is to summarize and critically analyze the available information about chlorophylls in VOO.     

Bupropion and cognitive-behavioral therapy for smoking cessation in women.

Gender data for bupropion suggest that it may be a particularly effective smoking cessation medication for women. It is not known whether the efficacy of this pharmacotherapy differs as a function of the psychotherapy with which it is administered. This study used a two level factorial design to examine the independent and interactive effects of medication (bupropion 300 mg/day vs. placebo) and psychotherapy (cognitive-behavioral therapy [CBT] vs. supportive therapy [ST]). In addition to testing the hypothesis that bupropion with CBT would be most effective of all the treatments, we examined medication compliance and its role in the efficacy of bupropion. Participants were 154 women, aged at least 30 years and smoking more than 10 cigarettes/day. Compliance with study medication was assessed using Medication Event Monitoring Systems (MEMS) over 7 weeks of treatment. Psychological interventions were delivered in 60-min weekly group sessions. Longitudinal analysis of abstinence outcomes from end of treatment (EOT) through 12 months after treatment revealed a significant interaction of medication and therapy. Higher abstinence rates at EOT and 3-, 6-, 9-, and 12-month follow-ups were observed when bupropion was delivered concurrently with CBT (44%, 24%, 30%, 23%, 17%) rather than with ST (18%, 1%, 8%, 5%, 2%). The bupropion-CBT combination, however, was not clearly superior to placebo, regardless of therapy assignment. Higher rates of medication compliance were positively predictive of abstinence, and this effect was most evident in the placebo condition. Findings provide only modest support for CBT as the preferred type of intensive therapy in conjunction with bupropion in women.     

Development of SNAP-tag fluorogenic probes for wash-free fluorescence imaging

The ability to specifically attach chemical probes to individual proteins represents a powerful approach to the study and manipulation of protein function in living cells. It provides a simple, robust and versatile approach to the imaging of fusion proteins in a wide range of experimental settings. However, a potential drawback of detection using chemical probes is the fluorescence background from unreacted or nonspecifically bound probes. In this report we present the design and application of novel fluorogenic probes for labeling SNAP-tag fusion proteins in living cells. SNAP-tag is an engineered variant of the human repair protein O(6)-alkylguanine-DNA alkyltransferase (hAGT) that covalently reacts with benzylguanine derivatives. Reporter groups attached to the benzyl moiety become covalently attached to the SNAP tag while the guanine acts as a leaving group. Incorporation of a quencher on the guanine group ensures that the benzylguanine probe becomes highly fluorescent only upon labeling of the SNAP-tag protein. We describe the use of intramolecularly quenched probes for wash-free labeling of cell surface-localized epidermal growth factor receptor (EGFR) fused to SNAP-tag and for direct quantification of SNAP-tagged β-tubulin in cell lysates. In addition, we have characterized a fast-labeling variant of SNAP-tag, termed SNAP(f), which displays up to a tenfold increase in its reactivity towards benzylguanine substrates. The presented data demonstrate that the combination of SNAP(f) and the fluorogenic substrates greatly reduces the background fluorescence for labeling and imaging applications. This approach enables highly sensitive spatiotemporal investigation of protein dynamics in living cells.     

Photoinduced interfacial electron transfer and lateral charge transport in molecular donor-acceptor photovoltaic systems

Nanostructured liquid/solid and solid/solid bulk heterojunctions designed for the conversion of solar energy offer ideal models for the investigation of light-induced ET dynamics at surfaces. Despite significant study of processes leading to charge generation in third-generation solar cells, a conclusive picture of the photophysics of these photovoltaic converters is still missing. More specifically searched is the link between the molecular structure of the interface and the kinetics of surface photoredox reactions. Fundamental scientific issues in this field are addressed by the research project undertaken in the frame of the NCCR MUST endeavor, an outline of which is given here.