Abstracts 1251-1506 and Author Index
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380 1249 476 bpm, (p=0.0001) and stroke volume: 31.9 ± 9.3 vs. 39.2 ± 5.5 µl (p=0.03); therefore in cardiac output: 13.1 ± 3.5 vs. 18.7 ± 3.2 µl/min CONSIDERABLE PROPORTION OF LEISHMANIA BRAZILIENSIS (p=0.002). There are relevant susceptibility and hemodynamic differences RRNA MOLECULES ARE POLYADENYLATED between these strains of mice during acute chagasic infection. Further characterizations of heart tissue histopathology, immunohistochemistry Marlene Jara Portocarreo, Jorge Arevalo and gene expression will investigate possible host factor determinants for Instituto de Medicina Tropical Alexander von Humboldt, Lima, Peru acute chagasic myocarditis. Leishmania parasites are ancestral eukaryotes with unusual characteristics like polycistronic transcription and RNA trans-splicing. Like other 1250A eukaryotes, their RNA ribosomal genes are tandemly repeated and transcribed by RNA polymerase I. Unlike other eukaryotes, Leishmania QUANTITATIVE KDNA ASSESSMENT DURING TREATMENT OF ribosomes have rRNA molecules of 18S, 5.8S, and 28S, with the latter MUCOSAL LEISHMANIASIS AS A POTENTIAL BIOMARKER OF one being split into six rRNAs (α.γ, β, δ, ζ and ε). The polyadenylation OUTCOME is a post-transcriptional process well known for mRNA but scarcely Marlene Jara1, Braulio M. Valencia1, Milena Alba1, Vanessa Adaui1, reported for rRNA. Our previous work on L. braziliensis and L. donovani Jorge Arevalo1, Alejandro Llanos-Cuentas1, Andrea K. Boggild2 demonstrated that at least the rRNA 28S ε undergo the polyadenylation 1 2 process and that its relative abundance varies in Leishmania promastigote Universidad Peruana Cayetano Heredia, Lima, Peru, University of Toronto, and amastigote stages. To determine if all rRNA gene subunits are Toronto, ON, Canada subjected to polyadenylation, we evaluated the 18S rRNA, 5.8S rRNA and Mucosal leishmaniasis (ML) is a disfiguring manifestation of infection with all the subunits homolog to 28S rRNA at stationary and logarithmic phase Leishmania (Viannia) spp. As there is no known biomarker of treatment promastigotes of the L. braziliensis strain MHOM/BR/75/M2904. We found outcome in ML, we evaluated the concentration of kinetoplast minicircle that all the rRNA subunits were polyadenylated. Moreover, we quantified DNA (kDNA) by cytology brush quantitative PCR before, during, and the absolute amount of polyadenylated and non-polyadenylated rRNA after treatment of ML in Peruvian patients. ML lesions were sampled by of the sub-units 18S, 5.8S and 28S α by Reverse Transcription-Real time cytology brushes for quantitative PCR at enrolment, days 14 and 21_28 quantitative PCR. In the logarithmic promastigotes, the percentage of of therapy, and 3-, 6-, or 12-mos after treatment. Parasite concentration polyadenylated rRNA 18S, rRNA 5.8S and rRNA 28S α were 0.378 ± 0.02 in tissue was correlated to demographic, clinical, and parasitologic (mean ± standard deviation), 4.55 ± 0.43 and 13.86 ± 0.95, respectively. factors. Twenty patients completed follow-up: 12 men and 8 women, The stationary promastigotes had higher percentages of polyadenylated with median age of 37 yrs (range 18_78 yrs). Fifteen patients were rRNA 18S (0.704 ±0.29, P=0.064) and rRNA 5.8S (5.69 ± 0.28, P=0.045) treated with sodium stibogluconate, and 5 with amphotericin B. Cure than the logarithmic promastigotes, whereas the 28S α did not show any was achieved in 17 patients, while 2 patients failed multiple courses of significant differences between log and stationary promastigotes. These therapy. Clinical outcome is unknown in 1 patient. Mean parasite load findings confirm a remarkable fact of Leishmania rRNA gene expression (PL) at enrolment was 85,614.8 ± 60,427.3 parasites per ug of tissue DNA (also present in L.amazonensis, data not shown) and it is related to the (par/ug tDNA). Three patterns of quantifiable kDNA during therapy and parasite growth. The biological role of this phenomenon remains unknown follow-up emerged: pattern 1 (N=10) was characterized by a mean PL of but its wide conservation in the genus Leishmania indicates it is an 170,867 ± 117,482.6 at enrolment, with sequential decline in PL during important one. and after therapy until kDNA was undetectable. Pattern 2 (N=4) was characterized by mean PL of 566.4 ± 306.4 at enrolment, with clearance of detectable kDNA by D14 of treatment, followed by an increased PL by 1250 D21-28 of treatment to 80.4 ± 32.1 par/ug tDNA. Pattern 3 (N=6) was PHENOTYPIC CHARACTERISTICS OF ACUTE CHAGASIC characterized by mean PL of 226.7 ± 116.1 at enrolment, with clearance of detectable kDNA during treatment, followed by increased PL by MYOCARDITIS AMONG C57 AND BALB/C MICE 6-mos follow-up to 36.6 ± 13.1 par/ug tDNA. Both patients who failed Andrés F. Henao-Martínez, Anne H. Agler, Timothy A. treatment demonstrated Pattern 1. Patterns 2 and 3 were associated with McKinsey, David A. Schwartz, Ivana V. Yang granulomatous inflammation (p=0.02). Younger age (33.5 vs. 64 yrs, University of Colorado Denver, Aurora, CO, United States p=0.10) and shorter ML duration (20.5 vs. 48 mos, p=0.11) are potentially correlated to sequential clearance (pattern 1). Baseline PL, sex, exposure Chagasic disease is a notable neglected tropical disease with high duration, lesion number, and ML location were not correlated to pattern of morbidity in Latin America and among immigrants to the US. The primary PL. We have demonstrated that the concentration of parasite kDNA in ML mechanism of mortality is cardiomyopathy and sudden death. Acute can be quantified by cytology brush sampling and quantitative PCR during chagasic myocarditis is consistently found in acute infections but little is and after treatment. Interim analysis demonstrates 3 distinct patterns known about its contribution to chronic forms of cardiomyopathy and of PL during and after treatment, which warrant further investigation. what host factors play a role in acute myocarditis. The aim of this study Granulomatous inflammation may predict rebound of PL during or after was to phenotypically characterize two strains of mice with differential treatment, though the clinical significance of this rebound is presently susceptibility to acute chagasic infection and correlate strain phenotypes unknown. with heart tissue gene expression. Laboratory mouse Tulahuen strain of Trypanosoma cruzi was grown in 3T3 fibroblast cell culture and tissue- derived trypomastigotes (TCT) were harvested from supernatant. C57 1251 and Balb/c mice were injected intraperiotneally with 0 or 150-200 TCT. COMPARISON OF TWO COMBINATION PARASITE LACTATE Weekly, mice were weighed and parasitemia was monitored via retro- DEHYDROGENASE-BASED RAPID TESTS FOR THE DIAGNOSIS orbital blood sample. At 4 weeks Brain natriuretic peptide (BNP) and OF MALARIA DUE TO PLASMODIUM KNOWLESI AND OTHER Troponin were measured in plasma and echocardiograms were obtained. 4-week mortality was 56.3% and 12.5% for Balb/c and C57 (p=0.009), PLASMODIUM SPECIES IN SABAH, MALAYSIA respectively. Infected Balb/c mice lost more weight than infected C57 Matthew J. Grigg1, T. William1, B. E. Barber1, U. Parameswaran1, mice (p=0.018). Parasitemia peaked at 2 weeks, but was not significantly T. W. Yeo2, N. M. Anstey2 different between strains due to high variation in counts: 500,781 ± 1Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia, 2Menzies 866,464 (Balb/c) vs. 140,625 ± 280,606 (C57) parasites/ml (p=0.12). For School of Health Research and Charles Darwin University, Darwin, Australia infected mice, BNP and troponin levels were not significantly different between strains, but BNP differed from uninfected mice. Echocardiograms Plasmodium knowlesi human infection has been reported throughout demonstrated differences in heart rate in BALB/c vs. C57 mice: 413 vs. South-East Asia, and is the most common cause of severe malaria in parts astmh.org 381 of Borneo. Microscopic misdiagnosis is common, and may impact prompt 1253 initiation of treatment shown to improve mortality outcomes. Previous studies have shown cross-reactivity of P. knowlesi with parasite lactate NATIONALLY REPRESENTATIVE SURVEYS OF MALARIA dehydrogenase monoclonal antibodies used to detect P. falciparum and DIAGNOSTIC CAPACITY IN THE PUBLIC SECTOR: FINDINGS P. vivax. Our initial evaluation of rapid diagnostic tests (RDTs) has not FROM GHANA AND BENIN demonstrated sufficient sensitivity for P. knowlesi, and no specific antibody 1 1 2 2 for P. knowlesi has been developed. At both tertiary and district referral Joseph Keating , Tim Finn , Luis Benavente , Chris Petruccelli , 2 1 3 4 sites in Sabah, Malaysia, we prospectively evaluated two combination RDTs Nicole Whitehurst , Thomas Eisele , Gilbert Dery , Ekow Biney , 5 1 for the diagnosis of uncomplicated and severe malaria. Firstly with a pan- Benjamin Fayomi , Joshua O. Yukich Plasmodium parasite lactate dehydrogenase (pan-pLDH) and P. falciparum 1Tulane University School of Public Health and Tropical Medicine, New specific parasite lactate dehyrogenase (PfLDH) RDT (Optimal-IT). Secondly Orleans, LA, United States, 2Medical Care Development International, with a non-P. falciparum pan-parasite lactate dehydrogenase (VOM), and Silver Spring, MD, United States, 3DERMED Consult LLC, Tamale, Ghana, P. falciparum histidine-rich protein-2 (HRP2) RDT (Carestart). Among 250 4Ghana Health Services, Accra, Ghana, 5Insitut d’Sciences Biomedicales patients hospitalised with PCR-confirmed P. knowlesi, P. falciparum and P. Appliquees (ISBA), Cotonou, Benin vivax monoinfection, the pre-treatment sensitivity of the pan-pLDH test for In many African settings, malaria cases are treated presumptively. The each species was 36% (49/137; 95% confidence interval [CI] 28 to 44%), absence of parasitological confirmation of malaria infection can lead to 75% (63/84; CI 64 to 84), and 83% (24/29; CI 64 to 94) respectively. The overtreatment of febrile illness with anti-malarial drugs, or the missing of PfLDH test sensitivities were 33% (45/137; CI 25 to 41), 77% (65/84; CI other potentially fatal conditions. The development of rapid diagnostic 67 to 86) and 14% (4/29; CI 4 to 32) respectively.