ABSTRACT
OBJECTIVES: Correlations are made between mainstream cigarette smoke deliveries of individual PAHs over multiple years. Average overall PAH deliveries in mainstream cigarette smoke by study year, mentholation, ring size, and manufacturer are compared. METHODS: Mainstream smoke deliveries were determined by GC/MS for 14 polycyclic aromatic hydrocarbons (PAHs) from selected cigarettes on the US market in 2002, 2004, 2007, and 2011. The mainstream smoke PAH emissions were measured under international standardization organization (ISO) smoking conditions. Pearson product-moment correlation was used to examine the linear relationship among the PAHs over multiple years. RESULTS: A number of the PAH analytes were statistically highly correlated with each other. The overall average for mainstream smoke deliveries of PAHs did not change significantly between study years. Similar levels in average PAH deliveries were seen for mentholated and non-mentholated cigarettes. CONCLUSIONS: The strong correlations between PAH compounds over multiple years show that a limited set of PAHs can predict deliveries of others with confidence over multiple years. A more limited panel of analytes may be considered when designing studies involving PAH measurements in mainstream smoke.
ABSTRACT
BACKGROUND: Over the past 50 years, antibiotics of choice for treatment of plague, including streptomycin, chloramphenicol, and tetracycline, have mostly become outdated or unavailable. To test gentamicin in the treatment of naturally occurring plague and the implications of its use in the treatment of bioterrorist plague, a randomized, comparative, open-label, clinical trial comparing monotherapy with gentamicin or doxycycline was conducted in Tanzania. METHODS: Sixty-five adults and children with symptoms of bubonic, septicemic, or pneumonic plague of < or =3 days duration were enrolled in the study. Bubo aspirates and blood were cultured for Yersinia pestis. Acute-phase and convalescent-phase serum samples were tested for antibody against fraction 1 antigen of Y. pestis. Thirty-five patients were randomized to receive gentamicin (2.5 mg/kg intramuscularly every 12 h for 7 days), and 30 patients were randomized to receive doxycycline (100 mg [adults] and 2.2 mg/kg [children] orally every 12 h for 7 days). Serum creatinine concentrations were measured before and after treatment, and peak and trough concentrations of antibiotics were measured. RESULTS: Three patients, 2 of whom were treated with gentamicin and 1 of whom was treated with doxycycline, died on the first or second day of treatment, and these deaths were attributed to advanced disease and complications including pneumonia, septicemia, hemorrhage, and renal failure at the start of therapy. All other patients experienced cure or an improved condition after receiving therapy, resulting in favorable response rates of 94% for gentamicin (95% CI, 81.1%-99.0%) and 97% for doxycycline (95% CI, 83.4%-99.8%). Y. pestis isolates obtained from 30 patients belonged to biotype antigua and were susceptible to gentamicin and doxycycline, which had MICs of 0.13 mg/L and 0.25-0.5 mg/L, respectively. Serum concentrations of antibiotics were within therapeutic ranges, and adverse events were infrequent. Patients treated with gentamicin demonstrated a modest increase in the mean serum creatinine concentration after treatment (P<.05, by paired t test). CONCLUSIONS: Both gentamicin and doxycycline were effective therapies for adult and pediatric plague, with high rates of favorable responses and low rates of adverse events.
