A DNA polymerase stop assay for G-quadruplex-interactive compounds

We have developed and characterized an assay for G-quadruplex-interactive compounds that makes use of the fact that G-rich DNA templates present obstacles to DNA synthesis by DNA polymerases. Using Taq DNA polymerase and the G-quadruplex binding 2, 6-diamidoanthraquinone BSU-1051, we find that BSU-1051 leads to enhanced arrest of DNA synthesis in the presence of K+by stabilizing an intramolecular G-quadruplex structure formed by four repeats of either TTGGGG or TTAGGG in the template strand. The data provide additional evidence that BSU-1051 modulates telomerase activity by stabilization of telomeric G-quadruplex DNA and point to a polymerase arrest assay as a sensitive method for screening for G-quadruplex-interactive agents with potential clinical utility.     

Quantitation and kinetic properties of hepatic microsomal and recombinant flavin-containing monooxygenases 3 and 5 from humans

For many profoundly hearing-impaired listeners (hearing loss > 90 dB HL) speechreading is the most important means of communication; amplified speech may provide, at best, additional information to speechreading. In order to improve audiovisual communication, three speech pattern elements comprising voice-fundamental frequency (f0), the first formant (F1), and the first and the second formant (F1F2) were presented as supplements to speechreading. A fourth condition consisted of a natural speech supplement, a fifth of speechreading only. Twenty subjects were tested; all audiovisual speech scores were significantly higher than the purely visual scores. Audiovisual scores for amplified, natural speech were significantly higher than those for f0 and F1F2 coded speech. Scores for natural speech and for F1 coded speech were not significantly different. The relations between the increase in audiovisual speech scores over the visual scores and measures of difference limen for frequency (DLf) and gap detection were not clear. The most prominent correlations with the speech scores were found for the DLf at 125 Hz and for gap detection.     

1alpha,25-dihydroxyvitamin D3 actions in LNCaP human prostate cancer cells are androgen-dependent

We and others have recently shown that 1alpha,25-dihydroxyvitamin D3 [1,25-(OH)2D3] significantly inhibits cell proliferation and increases secretion of prostate-specific antigen (PSA) in LNCaP cells, an androgen-responsive human prostate cancer cell line. The present study was designed to investigate the possible interactions between 1,25-(OH)2D3 and androgens in the regulation of LNCaP cellular function. LNCaP cell growth was dose-dependently inhibited by 1,25-(OH)2D3 (60% inhibition at 10 nM) when cells were cultured in medium supplemented with FBS (FBS medium). 1,25-(OH)2D3-treated cells showed a 5-fold increase in PSA secretion, similar to the increase seen in dihydrotestosterone (DHT)-treated cells. In combination, 1,25-(OH)2D3 and DHT synergistically enhanced PSA secretion 22-fold. This synergistic effect was even greater when cells were cultured in medium supplemented with charcoal-stripped serum (CSS medium), where endogenous steroids are substantially depleted. Under these conditions, 1,25-(OH)2D3 and DHT together stimulated PSA secretion up to 50-fold over the untreated control. Radioligand binding assays and Western blot analyses showed that the androgen receptor (AR) content was increased significantly by 1,25-(OH)2D3 at 48 h. Furthermore, the steady-state mRNA level of AR was up-regulated approximately 2-fold by 1,25-(OH)2D3 at 24 h. When cells were grown in CSS medium, 1,25-(OH)2D3 alone no longer inhibited cell growth or induced PSA secretion. Titration experiments revealed that the addition of DHT at 1 nM to the medium restored the antiproliferative activity of 1,25-(OH)2D3. Conversely, an antiandrogen, Casodex, completely blocked 1,25-(OH)2D3 antiproliferative and PSA stimulation activities when cells were cultured in FBS medium. In conclusion, these results demonstrate that the antiproliferative and PSA induction activities of 1,25-(OH)2D3 in LNCaP cells are dependent upon androgen action and that AR up-regulation by 1,25-(OH)2D3 likely contributes to the synergistic actions of 1,25-(OH)2D3 and DHT in these cells.     

Sexually transmitted disease among married Zambian women: the role of male and female sexual behaviour in prevention and management

Two methods of endotracheal intubation of patients lying on the ground were compared for ease and speed of intubation and minimization of complications in a crossover study of prehospital-oriented emergency physicians. Intubation of a mannequin was attempted by the physicians in either a left lateral decubitus (LLD) position or a kneeling (K) position, followed by the alternate position. The LLD position afforded more rapid intubation, better glottic visualization, and less dental trauma. Eighty-seven percent of physicians completely visualized the glottis in the LLD position, versus 33% of the K position group. Intubation times were 10.5 versus 14.6 seconds in the LLD and K positions, respectively (P < .001). The LLD position is a more effective position (in a mannequin model) than the K position for intubation of patients found lying on the ground, a frequent situation in prehospital care.     

Egg production capacity of Paragonimus pulmonalis in cats

In the present study, each of 43 cats was fed with a single metacercaria of Paragonimus pulmonalis and 2 cats (controls) with 2 metacercariae. They were killed 22-372 days postinfection. In the test group, 18 (41.9%) cats were infected, as well as the 2 cats in the control group. Among the 18 worms recovered from the test group, 9 found in the lungs were mature, whereas 5 mature and 4 immature worms were in the pleural cavity. Most eggs from worms encased in a cyst were passed in the feces. However, eggs from worms in the pleural cavity were only found on the lung surface and pleural cavity. Mature worms in cysts seemed to exhibit higher egg production capacity than those in the pleural cavity. Paired mature worms from a cyst laid more eggs than a single encysted mature worm in vitro at room temperature.