PubMed Central (PMC3 - NLM DTD)
Archive of life sciences journal literature at the U.S. National Institutes of Health (NIH), developed and managed by NIH's National Center for Biotechnology Information (NCBI) in the National Library of Medicine (NLM).
Pentoxifylline Reverses Chronic Experimental Chagasic Cardiomyopathy in Association with Repositioning of Abnormal CD8+ T-Cell Response - Pereira, Isabela Resende; Vilar-Pereira, Glaucia; Moreira, Otacilio Cruz; Ramos, Isalira Peroba; Gibaldi, Daniel; Britto, Constança; Moraes, Milton Ozório; Lannes-Vieira, Joseli
Chronic chagasic cardiomyopathy (CCC) is the main clinical manifestation of Chagas disease (CD), a neglected illness caused by the protozoan parasite Trypanosoma cruzi. More than hundred years after its discovery, CD continues to be a public health problem and millions of chronically infected people wait for an effective treatment. Chagasic cardiomyopathy is associated with CD8+ T-cell-enriched myocarditis, fibrosis and cardiac electrical and structural abnormalities, frequently progressing to heart failure. Presently, the available therapies only mitigate symptoms of CCC. Abnormalities in CD8+ T-cell compartment are present in CCC patients. Recently, we described the importance of CD8+ T-cells in the pathogenesis of...
Epidemiological Trends of Dengue Disease in Colombia (2000-2011): A Systematic Review - Villar, Luis Angel; Rojas, Diana Patricia; Besada-Lombana, Sandra; Sarti, Elsa
A systematic literature review was conducted to describe the epidemiology of dengue disease in Colombia. Searches of published literature in epidemiological studies of dengue disease encompassing the terms “dengue”, “epidemiology,” and “Colombia” were conducted. Studies in English or Spanish published between 1 January 2000 and 23 February 2012 were included. The searches identified 225 relevant citations, 30 of which fulfilled the inclusion criteria defined in the review protocol. The epidemiology of dengue disease in Colombia was characterized by a stable “baseline” annual number of dengue fever cases, with major outbreaks in 2001–2003 and 2010. The geographical spread of dengue disease...
Antibodies against Immature Virions Are Not a Discriminating Factor for Dengue Disease Severity - Rodenhuis-Zybert, Izabela A.; da Silva Voorham, Júlia M.; Torres, Silvia; van de Pol, Denise; Smit, Jolanda M.
Humoral immunity plays an important role in controlling dengue virus (DENV) infection. Antibodies (Abs) developed during primary infection protect against subsequent infection with the same dengue serotype, but can enhance disease following secondary infection with a heterologous serotype. A DENV virion has two surface proteins, envelope protein E and (pre)-membrane protein (pr)M, and inefficient cleavage of the prM protein during maturation of progeny virions leads to the secretion of immature and partially immature particles. Interestingly, we and others found that historically regarded non-infectious prM-containing DENV particles can become highly infectious in the presence of E- and prM-Abs. Accordingly, we hypothesized...
Immunization of Knock-Out α/β Interferon Receptor Mice against High Lethal Dose of Crimean-Congo Hemorrhagic Fever Virus with a Cell Culture Based Vaccine - Canakoglu, Nurettin; Berber, Engin; Tonbak, Sukru; Ertek, Mustafa; Sozdutmaz, Ibrahim; Aktas, Munir; Kalkan, Ahmet; Ozdarendeli, Aykut
Crimean-Congo hemorrhagic fever (CCHF) is an acute tick-borne zoonotic disease. The disease has been reported in many countries of Africa, Asia, the Middle East, and in Eurasia. During the past decade, new foci of CCHF have emerged in the Balkan Peninsula, southwest Russia, the Middle East, western China, India, Africa, and Turkey. CCHF virus produces severe hemorrhagic manifestations in humans with fatality rates up to 30%. Vaccine development efforts have been significantly hampered by a lack of animal models and therefore, no protective vaccine has been achieved. Lately, IFN α/β receptor deficient (IFNAR−/−) mice have been established as a novel...
Impact of Helminth Infection during Pregnancy on Cognitive and Motor Functions of One-Year-Old Children - Mireku, Michael O.; Boivin, Michael J.; Davidson, Leslie L.; Ouédraogo, Smaïla; Koura, Ghislain K.; Alao, Maroufou J.; Massougbodji, Achille; Cot, Michel; Bodeau-Livinec, Florence
The WHO recommends anthelmintics for pregnant women after their first trimester but the benefits remain unequivocal. Although the consequences of helminth infection during pregnancy on the health of pregnant women have been well studied, the impact on the early development of offspring has been understudied. Studies suggest that helminth infection in children may be associated with poor cognitive development, but very little is known whether a similar consequence exists for offspring of women infected with helminths during pregnancy. From our study, we found that women who had intestinal worm infection at least once during pregnancy, had children with lower cognitive...
Randomized Controlled Field Trial to Assess the Immunogenicity and Safety of Rift Valley Fever Clone 13 Vaccine in Livestock - Njenga, M. Kariuki; Njagi, Leonard; Thumbi, S. Mwangi; Kahariri, Samuel; Githinji, Jane; Omondi, Eunice; Baden, Amy; Murithi, Mbabu; Paweska, Janusz; Ithondeka, Peter M.; Ngeiywa, Kisa J.; Dungu, Baptiste; Donadeu, Meritxell; Munyua, Peninah M.
Although livestock vaccination is effective in preventing Rift Valley fever (RVF) outbreaks, there are concerns about safety and effectiveness of the only commercially available vaccine for the disease. Here, we conducted a field trial in Kenya to evaluate the safety and ability to induce protection for a new RVF vaccine, referred to as Clone 13, that was recently registered in South Africa. A total of 404 animals, consisting of cattle, sheep, and goats, were divided two groups and one group was vaccinated with Clone 13 vaccine while the other group was not vaccinated. The animals were followed for one year...
Epidemiological Changes in Leishmaniasis in Spain According to Hospitalization-Based Records, 1997–2011: Raising Awareness towards Leishmaniasis in Non-HIV Patients - Herrador, Zaida; Gherasim, Alin; Jimenez, B. Carolina; Granados, Marisol; San Martín, Juan Victor; Aparicio, Pilar
In Spain, Leishmania infantum is endemic, human visceral and cutaneous leishmaniasis cases occurring both in the Peninsula, as well as in the Balearic Islands. We aimed to describe the clinical characteristics of leishmaniasis patients and the changes in the disease evolution after the introduction of antiretroviral therapy in 1997. In this descriptive study, we used Spanish Centralized Hospital Discharge Database for the hospitalized leishmaniasis cases between 1997 and 2011. We included in the analysis only the records having leishmaniasis as the first registered diagnosis and calculated the hospitalization rates. Disease trend was described taking into account the HIV status. Adjusted...
Association of Symptoms and Severity of Rift Valley Fever with Genetic Polymorphisms in Human Innate Immune Pathways - Hise, Amy G.; Traylor, Zachary; Hall, Noémi B.; Sutherland, Laura J.; Dahir, Saidi; Ermler, Megan E.; Muiruri, Samuel; Muchiri, Eric M.; Kazura, James W.; LaBeaud, A. Desirée; King, Charles H.; Stein, Catherine M.
The underlying risk factors that lead to severe human Rift Valley Fever disease are unknown, but are likely multi-factorial. Host factors, such as innate immune genetic makeup, are likely important determinants of disease phenotype. This study investigated the association of 46 single nucleotide polymorphisms (SNPs) in genes encoding innate immune receptors, signaling pathways or mediators with RVF disease phenotype. Of the 46 SNPs tested, TLR3, TLR7, TLR8, MyD88, TRIF, MAVS, and RIG-I were repeatedly associated with severe RVF symptomatology, suggesting that these genes may have a robust association with RVFV-associated clinical outcomes.
Coinjection with TLR2 Agonist Pam3CSK4 Reduces the Pathology of
Leishmanization in Mice - Huang, Lu; Hinchman, Meleana; Mendez, Susana
Cutaneous leishmaniasis caused by Leishmania major is an
emergent, uncontrolled public health problem and there is no vaccine. A
promising prophylactic approach has been immunotherapy with Toll-like receptor
(TLR) agonists to enhance parasite-specific immune responses. We have previously
reported that vaccination of C57BL/6 mice with live L.
major plus the TLR9 agonist CpG DNA prevents lesion
development and confers immunity to reinfection. Our current study aims to
investigate whether other TLR agonists can be used in leishmanization without
induction of lesion formation. We found that live L.
major plus the TLR2 agonist Pam3CSK4 reduced the pathology
in both genetically resistant (C57BL/6) and susceptible (BALB/c) mouse strains.
The addition of Pam3CSK4 activated...
Exposure to Leishmania braziliensis Triggers Neutrophil Activation and Apoptosis - Falcão, Sarah A. C.; Weinkopff, Tiffany; Hurrell, Benjamin P.; Celes, Fabiana S.; Curvelo, Rebecca P.; Prates, Deboraci B.; Barral, Aldina; Borges, Valeria M.; Tacchini-Cottier, Fabienne; de Oliveira, Camila I.
Leishmania is the parasite responsible for the disease leishmaniasis, present in all continents. Leishmania parasites are spread through infected sand-flies and, during transmission into the vertebrate host, neutrophils are among the first cells to arrive at the infection site. Since neutrophils are key players at the frontline of defense against invading organisms, we investigated their response to Leishmania braziliensis. Importantly, L. braziliensis causes both Cutaneous and Mucocutaneous Leishmaniasis, two clinical manifestations characterized by their chronic development and by the presence of skin lesions with tissue destruction. Upon inoculation of mice with L. braziliensis, neutrophils rapidly arrive at the site of...
Development of a pHrodo-Based Assay for the Assessment of In Vitro and In Vivo Erythrophagocytosis during Experimental Trypanosomosis - Stijlemans, Benoit; Cnops, Jennifer; Naniima, Peter; Vaast, Axel; Bockstal, Viki; De Baetselier, Patrick; Magez, Stefan
Extracellular trypanosomes can cause a wide range of diseases and pathological complications in a broad range of mammalian hosts. One common feature of trypanosomosis is the occurrence of anemia, caused by an imbalance between erythropoiesis and red blood cell clearance of aging erythrocytes. In murine models for T. brucei trypanosomosis, anemia is marked by a very sudden non-hemolytic loss of RBCs during the first-peak parasitemia control, followed by a short recovery phase and the subsequent gradual occurrence of an ever-increasing level of anemia. Using a newly developed quantitative pHrodo based in vitro erythrophagocytosis assay, combined with FACS-based ex vivo and...
Relationship between Antibody Susceptibility and Lipopolysaccharide O-Antigen Characteristics of Invasive and Gastrointestinal Nontyphoidal Salmonellae Isolates from Kenya - Onsare, Robert S.; Micoli, Francesca; Lanzilao, Luisa; Alfini, Renzo; Okoro, Chinyere K.; Muigai, Anne W.; Revathi, Gunturu; Saul, Allan; Kariuki, Samuel; MacLennan, Calman A.; Rondini, Simona
Nontyphoidal Salmonellae (NTS) are an emerging major cause of invasive bacterial disease in African children aged less than 5 years and immunocompromised adults, with an estimated case fatality rate of 20–25%. NTS also cause diarrhoea, a killer of about 1.5 million young children annually, mainly in low- and middle-income countries. No vaccine against NTS is available, but improved understanding of the Salmonella bacteria that cause disease in Africa would help the development of new vaccines. The authors characterized a collection of 192 Kenyan NTS strains (114 S. Typhimurium and 78 S. Enteritidis) from blood and stool specimens. All strains could...
Why Latrines Are Not Used: Communities’ Perceptions and Practices Regarding Latrines in a Taenia solium Endemic Rural Area in Eastern Zambia - Thys, Séverine; Mwape, Kabemba E.; Lefèvre, Pierre; Dorny, Pierre; Marcotty, Tanguy; Phiri, Andrew M.; Phiri, Isaak K.; Gabriël, Sarah
Taenia solium cysticercosis is a neglected parasitic zoonosis occurring in many developing countries. Socio-cultural determinants related to its control remain unclear. Studies in Africa have shown that the underuse of sanitary facilities and the widespread occurrence of free-roaming pigs are the major risk factors for porcine cysticercosis. The study objective was to assess the communities’ perceptions, practices and knowledge regarding latrines in a T. solium endemic rural area in Eastern Zambia inhabited by the Nsenga ethno-linguistic group, and to identify possible barriers to their construction and use. A total of 21 focus group discussions on latrine use were organized separately...
Molecular Characterization of Cryptosporidium spp. among Children in Rural Ghana - Eibach, Daniel; Krumkamp, Ralf; Al-Emran, Hassan M.; Sarpong, Nimako; Hagen, Ralf Matthias; Adu-Sarkodie, Yaw; Tannich, Egbert; May, Jürgen
Cryptosporidium spp. are a frequent cause of diarrhoea worldwide. While both animal-to-human and human-to-human transmission has been reported from industrialized countries, human-to-human transmission clearly prevails in Sub-Saharan Africa. However, data on the distribution of zoonotic and human subtypes is limited for rural African regions, where children are in very close contact to animals. We conducted a case-control study with 2232 stool samples from symptomatic and asymptomatic children living in the rural Ashanti region of Ghana. The combination of molecular typing results and clinical data helped to untangle transmission routes and to analyze the association of clinical symptoms with specific Cryptosporidium...
Prevalence and Determinants of the Gender Differentials Risk Factors of Child Deaths in Bangladesh: Evidence from the Bangladesh Demographic and Health Survey, 2011 - Hossain, Md. Mosharaf; Mani, Kulanthayan K. C.; Islam, Md. Rafiqul
Children are a significant asset of a country. Child deaths are an important way to determine the health sector development. The effectiveness of the interventions is required to prevent child deaths. The purpose of this study is to identify the prevalence and risk factors of child deaths in Bangladesh. Data were collected from the Bangladesh Demographic and Health Survey, 2011. The results indicate that in Bangladesh there is an association with child deaths and mothers’ age, mothers’ education, social-economic status, birth interval, birth order, baby size and place delivered. For Bangladesh, this study recommends expanding female education to increase mothers’...
Toxocariasis Diagnosed in International Travelers at the Institute of Tropical Medicine, Antwerp, Belgium, from 2000 to 2013 - Van Den Broucke, Steven; Kanobana, Kirezi; Polman, Katja; Soentjens, Patrick; Vekemans, Marc; Theunissen, Caroline; Vlieghe, Erika; Van Esbroeck, Marjan; Jacobs, Jan; Van Den Enden, Erwin; Van Den Ende, Jef; Van Gompel, Alfons; Clerinx, Jan; Bottieau, Emmanuel
Although infection with Toxocara canis or T. catis (commonly referred as toxocariasis) appears to be highly prevalent in (sub)tropical countries, information on its frequency and presentation in returning travelers and migrants is scarce. In this study, we reviewed all cases of asymptomatic and symptomatic toxocariasis diagnosed during post-travel consultations at the reference travel clinic of the Institute of Tropical Medicine, Antwerp, Belgium. Toxocariasis was considered as highly probable if serum Toxocara-antibodies were detected in combination with symptoms of visceral larva migrans if present, elevated eosinophil count in blood or other relevant fluid and reasonable exclusion of alternative diagnosis, or definitive...
Exposure of Trypanosoma brucei to an N-acetylglucosamine-Binding Lectin Induces VSG Switching and Glycosylation Defects Resulting in Reduced Infectivity - Castillo-Acosta, Víctor M.; Ruiz-Pérez, Luis M.; Van Damme, Els J. M.; Balzarini, Jan; González-Pacanowska, Dolores
Trypanosoma brucei variant surface glycoproteins (VSG) are glycosylated by both paucimannose and oligomannose structures which are involved in the formation of a protective barrier against the immune system. Here, we report that the stinging nettle lectin (UDA), with predominant N-acetylglucosamine-binding specificity, interacts with glycosylated VSGs and kills parasites by provoking defects in endocytosis together with impaired cytokinesis. Prolonged exposure to UDA induced parasite resistance based on a diminished capacity to bind the lectin due to an enrichment of biantennary paucimannose and a reduction of triantennary oligomannose structures. Two molecular mechanisms involved in resistance were identified: VSG switching and modifications in...