Antibacterial Activity of Nitrogen-Doped Carbon Dots Enhanced by Atomic Dispersion of Copper.

Antibiotic resistance is an imminent threat to human health, requiring the development of effective alternate antibacterial agents. One such alternative includes nanoparticle (photo)catalysts that are good at producing reactive oxygen species (ROS). Herein, we report the design and preparation of nitrogen-doped carbon dots functionalized with atomically dispersed copper centers by Cu-N coordination (Cu/NCD) that exhibit apparent antibacterial activity toward Gram-negative Escherichia coli (E. coli) under photoirradiation. The growth of E. coli cells is found to be markedly inhibited by Cu/NCD under 365 nm photoirradiation, whereas no apparent inhibition is observed in the dark or with the copper-free carbon dots alone. This is ascribed to the prolonged photoluminescence lifetime of Cu/NCD that facilitates the separation of photogenerated electron-hole pairs and ROS formation. The addition of tert-butyl alcohol is found to completely diminish the antimicrobial activity, suggesting that hydroxyl radicals are responsible for microbial death. Consistent results are obtained from fluorescence microscopic studies using CellROX green as the probe. Similar bactericidal behaviors are observed with Gram-positive Staphylococcus epidermidis (S. epidermidis). The copper content within the carbon material is optimized at a low loading of 1.09 wt %, reducing the possibility of toxic copper-ion leaching. Results from this study highlight the significance of carbon-based nanocomposites with isolated metal species as potent antimicrobial reagents.

Costs associated with acute respiratory illness and select virus infections in hospitalized children, El Salvador and Panama, 2012-2013.

BACKGROUND AND OBJECTIVES: Although acute respiratory illness (ARI) is a leading cause of hospitalization among young children, few data are available about cost of hospitalization in middle-income countries. We estimated direct and indirect costs associated with severe ARI resulting in hospitalization among children aged <10 years in El Salvador and Panama through the societal perspective. METHODS: During 2012 and 2013, we surveyed caregivers of children hospitalized with ARI about their direct medical (i.e., outpatient consultation, medications, hospital fees), non-medical (transportation, childcare), and indirect costs (lost wages) at discharge and 7 days after discharge. We multiplied subsidized hospital bed costs derived from administrative data by hospitalization days to estimate provider costs. RESULTS: Overall, 638 children were enrolled with a median age of 12 months (IQR 6-23). Their median length of hospitalization was 4 days (IQR 3-6). In El Salvador, caregivers incurred a median of US$38 (IQR 22-72) in direct and indirect costs per illness episode, while the median government-paid hospitalization cost was US$118 (IQR 59-384) generating an overall societal cost of US$219 (IQR 101-416) per severe ARI episode. In Panama, caregivers incurred a median of US$75 (IQR 39-135) in direct and indirect costs, and the health-care system paid US$280 (IQR 150-420) per hospitalization producing an overall societal cost of US$393 (IQR 258-552). CONCLUSIONS: The cost of severe ARI to caregivers and the health care system was substantive. Our estimates will inform models to estimate national costs of severe ARI and cost-benefit of prevention and treatment strategies.

A randomized, double-blind, placebo-controlled trial evaluating the safety of early oseltamivir treatment among children 0-9 years of age hospitalized with influenza in El Salvador and Panama.

BACKGROUND: Oseltamivir reduces symptom duration among children with uncomplicated influenza, but few data exist on treatment efficacy and tolerability among hospitalized children, particularly among infants aged <1 year. We evaluated tolerability and efficacy of oseltamivir treatment of children aged 0-9 years hospitalized with influenza. METHODS: We conducted a double-blind, randomized, placebo-controlled trial at tertiary care hospitals in El Salvador and Panama. Primary outcomes were length of hospitalization and increased work of breathing. Children were eligible if hospitalized <7 days after symptom onset with cough or sore throat plus tachypnea. Children were randomized 1:1 to receive oseltamivir or placebo; had swabs collected at enrollment for influenza RT-PCR testing; were assessed at enrollment and every 12 h for work of breathing; and were followed for adverse events through 7 days after discharge. Analyses were intention-to-treat. RESULTS: Overall, 683 children were randomized (oseltamivir, n = 341, placebo n = 342). Fifty-three percent were aged <1 year and 30 had influenza (oseltamivir, n = 19; placebo, n = 11). The study was terminated early after enrollment of 21% of the sample size due to lower than anticipated participant accrual. Using Kaplan-Meier analysis, there was no significant difference in median length of hospitalization (3 days, IQR 2-4 vs. 5 days, IQR 3-7, p = 0.22) and increased work of breathing (36 h, IQR 24-72 vs. 96 h, IQR 13-108, p = 0.14) between oseltamivir versus placebo recipients. There was no difference in adverse events between groups. CONCLUSION: Oseltamivir treatment was well tolerated among hospitalized children, including among infants aged <1 year.

What Is the Added Benefit of Oropharyngeal Swabs Compared to Nasal Swabs Alone for Respiratory Virus Detection in Hospitalized Children Aged <10 Years?

We evaluated the added value of collecting both nasal and oropharyngeal swabs, compared with collection of nasal swabs alone, for detection of common respiratory viruses by reverse transcription-polymerase chain reaction in hospitalized children aged <10 years. Nasal swabs had equal or greater sensitivity than oropharyngeal swabs for detection of respiratory syncytial virus, adenovirus, human metapneumovirus, rhinovirus, and influenza virus but not parainfluenza virus. The addition of an oropharyngeal swab, compared with use of a nasal swab alone, increased the frequency of detection of each respiratory virus by no more than 10% in children aged <10 years.