Search tips
Search criteria

Results 1-7 (7)

Clipboard (0)

Select a Filter Below

Year of Publication
Document Types
1.  Toward a Surrogate Marker of Malaria Exposure: Modeling Longitudinal Antibody Measurements under Outbreak Conditions 
PLoS ONE  2011;6(7):e21826.
Biomarkers of exposure to Plasmodium falciparum would be a useful tool for the assessment of malaria burden and analysis of intervention and epidemiological studies. Antibodies to pre-erythrocytic antigens represent potential surrogates of exposure.
Methods and Findings
In an outbreak cohort of U.S. Marines deployed to Liberia, we modeled pre- and post-deployment IgG against P. falciparum sporozoites by immunofluorescence antibody test, and both IgG and IgM against the P. falciparum circumsporozoite protein by enzyme-linked immunosorbant assay. Modeling seroconversion thresholds by a fixed ratio, linear regression or nonlinear regression produced sensitivity for identification of exposed U.S. Marines between 58–70% and specificities between 87–97%, compared with malaria-naïve U.S. volunteers. Exposure was predicted in 30–45% of the cohort.
Each of the three models tested has merits in different studies, but further development and validation in endemic populations is required. Overall, these models provide support for an antibody-based surrogate marker of exposure to malaria.
PMCID: PMC3144875  PMID: 21818270
2.  Exposure to Bioterrorism and Mental Health Response among Staff on Capitol Hill 
The October 2001 anthrax attacks heralded a new era of bioterrorism threat in the U.S. At the time, little systematic data on mental health effects were available to guide authorities' response. For this study, which was conducted 7 months after the anthrax attacks, structured diagnostic interviews were conducted with 137 Capitol Hill staff workers, including 56 who had been directly exposed to areas independently determined to have been contaminated. Postdisaster psychopathology was associated with exposure; of those with positive nasal swab tests, PTSD was diagnosed in 27% and any post-anthrax psychiatric disorder in 55%. Fewer than half of those who were prescribed antibiotics completed the entire course, and only one-fourth had flawless antibiotic adherence. Thirty percent of those not exposed believed they had been exposed; 18% of all study participants had symptoms they suspected were symptoms of anthrax infection, and most of them sought medical care. Extrapolation of raw numbers to large future disasters from proportions with incorrect belief in exposure in this limited study indicates a potential for important public health consequences, to the degree that people alter their healthcare behavior based on incorrect exposure beliefs. Incorrect belief in exposure was associated with being very upset, losing trust in health authorities, having concerns about mortality, taking antibiotics, and being male. Those who incorrectly believe they were exposed may warrant concern and potential interventions as well as those exposed. Treatment adherence and maintenance of trust for public health authorities may be areas of special concern, warranting further study to inform authorities in future disasters involving biological, chemical, and radiological agents.
PMCID: PMC2956562  PMID: 20028246
4.  Lipid Profile Remodeling in Response to Nitrogen Deprivation in the Microalgae Chlorella sp. (Trebouxiophyceae) and Nannochloropsis sp. (Eustigmatophyceae) 
PLoS ONE  2014;9(8):e103389.
Many species of microalgae produce greatly enhanced amounts of triacylglycerides (TAGs), the key product for biodiesel production, in response to specific environmental stresses. Improvement of TAG production by microalgae through optimization of growth regimes is of great interest. This relies on understanding microalgal lipid metabolism in relation to stress response in particular the deprivation of nutrients that can induce enhanced TAG synthesis. In this study, a detailed investigation of changes in lipid composition in Chlorella sp. and Nannochloropsis sp. in response to nitrogen deprivation (N-deprivation) was performed to provide novel mechanistic insights into the lipidome during stress. As expected, an increase in TAGs and an overall decrease in polar lipids were observed. However, while most membrane lipid classes (phosphoglycerolipids and glycolipids) were found to decrease, the non-nitrogen containing phosphatidylglycerol levels increased considerably in both algae from initially low levels. Of particular significance, it was observed that the acyl composition of TAGs in Nannochloropsis sp. remain relatively constant, whereas Chlorella sp. showed greater variability following N-deprivation. In both algae the overall fatty acid profiles of the polar lipid classes were largely unaffected by N-deprivation, suggesting a specific FA profile for each compartment is maintained to enable continued function despite considerable reductions in the amount of these lipids. The changes observed in the overall fatty acid profile were due primarily to the decrease in proportion of polar lipids to TAGs. This study provides the most detailed lipidomic information on two different microalgae with utility in biodiesel production and nutraceutical industries and proposes the mechanisms for this rearrangement. This research also highlights the usefulness of the latest MS-based approaches for microalgae lipid research.
PMCID: PMC4149361  PMID: 25171084
5.  Supporting the Creation of New Institutional Review Boards in Developing Countries: The U.S. Naval Medical Research Center Detachment Experience 
Military medicine  2008;173(10):975-977.
The U.S. Naval Medical Research Center Detachment (NMRCD) has worked in Peru since 1983, conducting research on diseases of military importance in large part by interacting with multiple research partners across the scientific community of Central America and South America. Over the years, NMRCD has had research collaborations in Guatemala, Nicaragua, Costa Rica, Belize, Honduras, Suriname, Venezuela, Colombia, Ecuador, Bolivia, Chile, Uruguay, Paraguay, and Argentina. In addition to the various infectious diseases research collaborations, NMRCD has supported capacity building for research ethics and the creation of new institutional review boards. This article describes the contributions of NMRCD to research ethics training in Central America and South America, with specific emphasis on the support given to the creation of new institutional review boards.
PMCID: PMC4042429  PMID: 19160615
6.  An Outbreak of Plasmodium falciparum Malaria in U.S. Marines Deployed to Liberia 
In 2003, 44 U.S. Marines were evacuated from Liberia with either confirmed or presumed Plasmodium falciparum malaria. An outbreak investigation showed that only 19 (45%) used insect repellent, 5 (12%) used permethrin-treated clothing, and none used bed netting. Adherence with weekly mefloquine (MQ) was reported by 23 (55%). However, only 4 (10%) had serum MQ levels high enough to correlate with protection (> 794 ng/mL), and 9 (22%) had evidence of steady-state kinetics (MQ carboxy metabolite/MQ > 3.79). Tablets collected from Marines met USP identity and dissolution specifications for MQ. Testing failed to identify P. falciparum isolates with MQ resistance. This outbreak resulted from under use of personal protective measures and inadequate adherence with chemophrophylaxis. It is essential that all international travelers make malaria prevention measures a priority, especially when embarking to regions of the world with high transmission intensity such as west Africa.“Good doctors are of no use without good discipline. More than half the battle against disease is not fought by doctors, but by regimental officers. It is they who see that the daily dose of mepacrine (anti-malarial chemoprophylactic drug used in WW II) is taken…if mepacrine was not taken, I sacked the commander. I only had to sack three; by then the rest had got my meaning.”—Lieutenant General William Slim (1891–1970), Burma Campaign, 1943
PMCID: PMC2911167  PMID: 20682864
7.  Research Ethics Training in Peru: A Case Study 
PLoS ONE  2008;3(9):e3274.
With the rapidly increasing number of health care professionals seeking international research experience, comes an urgent need for enhanced capacity of host country institutional review boards (IRB) to review research proposals and ensure research activities are both ethical and relevant to the host country customs and needs. A successful combination of distance learning, interactive courses and expert course instructors has been applied in Peru since 2004 through collaborations between the U.S. Naval Medical Research Center Detachment, the University of Washington and the Department of Clinical Bioethics of the National Institutes of Health to provide training in ethical conduct of research to IRB members and researchers from Peru and other Latin American countries. All training activities were conducted under the auspices of the Peruvian National Institute of Health (INS), Ministry of Health. To date, 927 people from 12 different Latin American countries have participated in several of these training activities. In this article we describe our training model.
PMCID: PMC2538562  PMID: 18818763

Results 1-7 (7)