Role of pyrite in formation of hydroxyl radicals in coal: possible implications for human health

Background  

Exposure to ambient particulate matter has been associated with a number of adverse health effects. Particle characteristics such as size, surface area and chemistry seem to influence the negative effects of particles. In this study, combustion particles from vehicle exhaust and wood smoke, currently used in biological experiments, were analysed with respect to microstructure and chemistry.     

The Puzzle of RNAs that Target Gene Promoters

Setting the right target : Most researchers who use small RNAs in mammalian cells assume that mRNA will be the target. Recent studies suggest that small RNAs can also target chromosomal DNA.

     

Swagger, sway, and sexuality: Judging sexual orientation from body motion and morphology.

People can accurately judge the sexual orientation of others, but the cues they use have remained elusive. In 3 studies, the authors examined how body shape and motion affect perceived sexual orientation. In 2 studies, participants judged the sexual orientation of computer-generated animations in which body shape and motion were manipulated. Gender-typical combinations (e.g., tubular body moving with shoulder swagger or hourglass body moving with hip sway) were perceived generally to be heterosexual; gender-atypical combinations were perceived generally to be homosexual. These effects were stronger for male targets. Body shape affected perceived sexual orientation of women, but motion affected perceived sexual orientation of both men and women. Study 3 replicated and extended these findings. Participants judged dynamic outlines of real people (men and women, both gay and straight) in which body shape and motion were measured. Again, gender-atypical body motion affected perceived sexual orientation and, importantly, affected accuracy as well. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Number and stoichiometry of subunits in the native atrial G-protein-gated K+ channel, IKACh

The G-protein-regulated, inwardly rectifying K+ (GIRK) channels are critical for functions as diverse as heart rate modulation and neuronal post-synaptic inhibition. GIRK channels are distributed predominantly throughout the heart, brain, and pancreas. In recent years, GIRK channels have received a great deal of attention for their direct G-protein betagamma (Gbetagamma) regulation. Native cardiac IKACh is composed of GIRK1 and GIRK4 subunits (Krapivinsky, G., Gordon, E. A., Wickman, K. A., Velimirovic, B., Krapivinsky, L., and Clapham, D. E. (1995) Nature 374, 135-141). Here, we examine the quaternary structure of IKACh using a variety of complementary approaches. Complete cross-linking of purified atrial IKACh protein formed a single adduct with a total molecular weight that was most consistent with a tetramer. In addition, partial cross-linking of purified IKACh produced subsets of molecular weights consistent with monomers, dimers, trimers, and tetramers. Within the presumed protein dimers, GIRK1-GIRK1 and GIRK4-GIRK4 adducts were formed, indicating that the tetramer was composed of two GIRK1 and two GIRK4 subunits. This 1:1 GIRK1 to GIRK4 stoichiometry was confirmed by two independent means, including densitometry of both silver-stained and Western-blotted native atrial IKACh. Similar experimental results could potentially be obtained if GIRK1 and GIRK4 subunits assembled randomly as 2:2 and equally sized populations of 3:1 and 1:3 tetramers. We also show that GIRK subunits may form homotetramers in expression systems, although the evidence to date suggests that GIRK1 homotetramers are not functional. We conclude that the inwardly rectifying atrial K+ channel, IKACh, a prototypical GIRK channel, is a heterotetramer and is most likely composed of two GIRK1 subunits and two GIRK4 subunits.     

Evidence of latency and reactivation of both herpes simplex virus (HSV)-1 and HSV-2 in the genital region

While superinfection with different herpes simplex virus (HSV) types has been demonstrated in animals, the ability of the two HSV types to colonize and reactivate in the same anatomic region in humans has not been well demonstrated. In 6 patients, both HSV-1 and HSV-2 was recovered from genital lesions. In 4 of them, who initially acquired genital HSV-1 infection, subsequent HSV-2 infection presented as a prolonged episode of genital lesions and a marked increase in the frequency of genital recurrences. While most of the subsequent clinical reactivations were HSV-2, in 2 patients the recurrence rate of genital HSV-1 increased after the acquisition of HSV-2. These data demonstrate the ability of a second HSV type to infect the same anatomic region and illustrate the difference in reactivation frequency of the two types in the same person. Typing of HSV isolates may be useful in persons with recent alteration in recurrence rates of genital HSV.     

Taxol plus recombinant human granulocyte-colony stimulating factor as initial and as salvage chemotherapy for metastatic breast cancer: a preliminary report

Twenty-eight patients received Taxol as their first chemotherapy for stage IV breast cancer. An additional 51 patients with extensive prior exposure to other chemotherapeutic agents received Taxol as salvage therapy. We found significant activity for the drug in both situations, as well as a strong clinical suggestion of non-cross-resistance with doxorubicin. An excellent response in previously irradiated skin was noted in one case. The routine use of recombinant human granulocyte-colony stimulating factor seemed to ameliorate some of the dose-limiting toxicity of neutropenia. Other toxicity was mild to moderate in most cases. With further development, Taxol should play a significant role in the systemic management of breast cancer.     

Confirmatory factor analysis of the Fear Questionnaire in panic disorder with agoraphobia.

The Fear Questionnaire responses of 390 patients with panic disorder with agoraphobia were used in a confirmatory factor analysis. The results provide strong support for the 3-factor model of this scale (agoraphobia, social phobia, blood/injury phobia) and the multidimensional model of fears proposed by W. A. Arrindell (1980). The presence of fear clusters other than agoraphobia existing in panic disorder is also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Association between cytomegalovirus seroconversion and upper genital tract infection among women attending a sexually transmitted disease clinic: a prospective study

To study relationships between acquisition of cytomegalovirus (CMV), sexual activity, and sexually transmitted diseases, 245 CMV-seronegative women were followed (median, 23 months) in a sexually transmitted disease clinic between 1980 and 1988. Thirty-six (15%) seroconverted (10%-12%/year). At entry, seroconverters were younger (P = .03), were younger at sexual debut (P = .004), and had more sex partners (P = .004) than non-seroconverters. During follow-up, seroconverters had more sex partners, had more new sex partners (P = .05 for each), and were more likely to have gonorrhea, chlamydia, or pelvic inflammatory disease. At seroconversion, Chlamydia trachomatis was isolated from cervix in 14%, versus 3% of non-seroconverters (odds ratio [OR], 4.5; 95% confidence interval [CI], 1.3-14.9). Signs of upper genital tract infection were present in 8% of seroconverters versus 2% of non-seroconverters (OR, 4.7; 95% CI, 1.0-21.8). Acquisition of CMV in these women was associated with sexual activity, sexually transmitted diseases, and signs of upper genital tract infection.     

Resonant coupling between surface vibrations and electronic states in silicon nanocrystals at the strong confinement regime

A striking correlation between infrared photoinduced absorption spectra and the photoluminescence from silicon nanocrystals indicates that quantized electronic sublevels of the nanocrystals are resonantly coupled to surface vibrational modes via a polarization field produced by coherent longitudinal polar vibrations. Our experimental results and model support the assumption that the mechanism responsible for the efficient photoluminescence from silicon nanocrystals should be assigned to inhibition of nonradiative channels rather than enhancement of radiative channels.