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Find video protocols related to scientific articles indexed in Pubmed.
A fast, efficient and simple method for the synthesis of cyclic alkenyl fluorides by a fluorinative carbocyclization reaction.
Chem. Commun. (Camb.)
PUBLISHED: 10-09-2014
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A simple transformation of alkynol or enyne derivatives into cyclic alkenyl fluorides by using tetrafluoroboric acid as the proton and fluoride source is reported. This study includes the first biomimetic cationic cyclization/nucleophilic fluorination reaction of polyenyne derivatives to give terpenoid derivatives.
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Malaria and HIV Infection in Mozambican Pregnant Women Are Associated With Reduced Transfer of Antimalarial Antibodies to Their Newborns.
J. Infect. Dis.
PUBLISHED: 09-30-2014
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?Malaria and human immunodeficiency virus (HIV) infection during pregnancy affect the transplacental transfer of antibodies against several pathogens from mother to fetus, although the effect of malaria and HIV infection on the transfer of antimalarial antibodies remains unclear.
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Evaluation of a universal coverage bed net distribution campaign in four districts in Sofala Province, Mozambique.
Malar. J.
PUBLISHED: 08-26-2014
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Malaria is the leading cause of death in Mozambique in children under five years old. In 2009, Mozambique developed a novel bed net distribution model to increase coverage, based on assumptions about sleeping patterns. The coverage and impact of a bed net distribution campaign using this model in four districts in Sofala Province, Mozambique was evaluated.
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In vivo efficacy of artemether-lumefantrine and artesunate-amodiaquine for the treatment of uncomplicated falciparum malaria in children: a multisite, open-label, two-cohort, clinical trial in Mozambique.
Malar. J.
PUBLISHED: 08-10-2014
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Mozambique adopted artemisinin-based combination therapy (ACT) for the treatment of uncomplicated Plasmodium falciparum malaria in the year 2006, and since 2009 artemether-lumefantrine (AL) and artesunate-amodiaquine (ASAQ) have been proposed as alternative first-line treatments. A multicentre study was conducted in five sites across the country to assess the in vivo efficacy and tolerability of these two drugs.
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Development of attention networks and their interactions in childhood.
Dev Psychol
PUBLISHED: 07-28-2014
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In the present study, we investigated developmental trajectories of alerting, orienting, and executive attention networks and their interactions over childhood. Two cross-sectional experiments were conducted with different samples of 6- to 12-year-old children using modified versions of the attention network task (ANT). In Experiment 1 (N = 106), alerting and orienting cues were independently manipulated, thus allowing examination of interactions between these 2 networks, as well as between them and the executive attention network. In Experiment 2 (N = 159), additional changes were made to the task in order to foster exogenous orienting cues. Results from both studies consistently revealed separate developmental trajectories for each attention network. Children younger than 7 years exhibited stronger benefits from having an alerting auditory signal prior to the target presentation. Developmental changes in orienting were mostly observed on response accuracy between middle and late childhood, whereas executive attention showed increases in efficiency between 7 years and older ages, and further improvements in late childhood. Of importance, across both experiments, significant interactions between alerting and orienting, as well as between each of these and the executive attention network, were observed. Alerting cues led to speeding shifts of attention and enhancing orienting processes. Also, both alerting and orienting cues modulated the magnitude of the flanker interference effect. These findings inform current theoretical models of human attention and its development, characterizing for the first time, the age-related course of attention networks interactions that, present in adults, stem from further refinements over childhood.
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Shigella isolates from the global enteric multicenter study inform vaccine development.
Clin. Infect. Dis.
PUBLISHED: 06-23-2014
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Shigella, a major diarrheal disease pathogen worldwide, is the target of vaccine development. The Global Enteric Multicenter Study (GEMS) investigated burden and etiology of moderate-to-severe diarrheal disease in children aged <60 months and matched controls without diarrhea during 3 years at 4 sites in Africa and 3 in Asia. Shigella was 1 of the 4 most common pathogens across sites and age strata. GEMS Shigella serotypes are reviewed to guide vaccine development.
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Risk factors for a poor outcome among children admitted with clinically severe pneumonia to a university hospital in Rabat, Morocco.
Int. J. Infect. Dis.
PUBLISHED: 06-18-2014
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Data on prognostic factors among children with severe pneumonia are scarce in middle-income countries. We investigated prognostic factors for an adverse outcome among children admitted to the Hôpital d'Enfants de Rabat, Morocco with World Health Organization-defined clinically severe pneumonia (CSP).
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Getting ready for malaria elimination: a check list of critical issues to consider.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 06-07-2014
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In recent years, a renewed interest in malaria elimination and eradication has emerged and seems to be rooting in the minds of the scientific community, public health specialists, funding bodies, policy makers and politicians. Malaria eradication will certainly benefit from improved and innovative tools; notwithstanding novel knowledge in fields ranging from basic science to mathematical modelling and health systems research. However, the elimination of malaria also encompasses a broad range of essential aspects that countries and other actors need to consider when thinking of embarking on such an adventure, including the implementation of innovative strategies, the ability to incorporate the most up-to-date evidence into policy, the integration of malaria into the broader health agenda, the strengthening of surveillance and health systems, capacity building, funding, advocacy and, very importantly, research. While in some cases this enthusiasm is clearly justified, some countries are still a long way from realistically advancing towards elimination. This paper attempts to provide guidance on all the necessary issues that should be considered when initiating a malaria elimination program.
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Sensitivity and specificity of a rapid point-of-care test for active yaws: a comparative study.
Lancet Glob Health
PUBLISHED: 05-31-2014
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To eradicate yaws, national control programmes use the Morges strategy (initial mass treatment and biannual resurveys). The resurvey component is designed to actively detect and treat remaining yaws cases and is initiated on the basis of laboratory-supported reactive non-treponemal serology (using the rapid plasma reagin [RPR] test). Unfortunately, the RPR test is available rarely in yaws-endemic areas. We sought to assess a new point-of-care assay-the Dual Path Platform (DPP) syphilis assay, which is based on simultaneous detection of antibodies to treponemal and non-treponemal antigens-for guiding use of antibiotics for yaws eradication. A secondary goal was to ascertain at what timepoint the DPP assay line reverted to negative after treatment.
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Plasma advanced oxidative protein products are associated with anti-oxidative stress pathway genes and malaria in a longitudinal cohort.
Malar. J.
PUBLISHED: 03-27-2014
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Advanced oxidation protein products (AOPP) are newly identified efficient oxidative stress biomarkers. In a longitudinal birth cohort the effects were investigated of genetic polymorphisms in five oxidative pathway genes on AOPP levels.
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Impact of age of first exposure to Plasmodium falciparum on antibody responses to malaria in children: a randomized, controlled trial in Mozambique.
Malar. J.
PUBLISHED: 03-22-2014
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The impact of the age of first Plasmodium falciparum infection on the rate of acquisition of immunity to malaria and on the immune correlates of protection has proven difficult to elucidate. A randomized, double-blind, placebo-controlled trial using monthly chemoprophylaxis with sulphadoxine-pyrimethamine plus artesunate was conducted to modify the age of first P. falciparum erythrocytic exposure in infancy and assess antibodies and malaria risk over two years.
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The epidemiology and aetiology of infections in children admitted with clinical severe pneumonia to a university hospital in Rabat, Morocco.
J. Trop. Pediatr.
PUBLISHED: 02-25-2014
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Scarce and limited epidemiological, clinical and microbiological data are available regarding paediatric respiratory tract infections in the Kingdom of Morocco, a middle-income country in northwestern Africa. The results of hospital-based surveillance aiming at describing the aetiology and epidemiology of respiratory distress among children <5 years of age are presented.
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Duration of vaccine efficacy against malaria: 5th year of follow-up in children vaccinated with RTS,S/AS02 in Mozambique.
Vaccine
PUBLISHED: 02-12-2014
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A primary concern for the RTS,S malaria vaccine candidate is duration of protection. The ongoing Phase III trial reported evidence of waning efficacy within the first year following vaccination. Multiple Phase IIb trials demonstrated early waning of efficacy. The longest duration of protection for RTS,S recorded to date was in a trial of a cohort of 1605 Mozambican children age 1-4 yr at the time of immunization (C1), which showed an overall efficacy against clinical malaria of 30.5% over 43 subsequent months of surveillance. A significant reduction in parasite prevalence in RTS,S vaccinees indicated that the vaccine continued to protect at the end of this period. Although follow-up for recording incident cases of clinical malaria was stopped at 45 months, we were interested in evidence of further durability of protection, and revisited the cohort at 63 months, recording the secondary trial endpoint, prevalence of asexual Plasmodium falciparum parasitemia, in the RTS,S and comparator vaccine groups as a proxy for efficacy. As a comparator, we also visited the contemporaneous cohort of 417 children (C2), which showed waning efficacy after 6 months of follow-up. We also assessed anti-circumsporozoite antibody titers. These results were compared with those of other Phase IIb trials. Prevalence of parasitemia was not significantly lower in the RTS,S/AS02 group compared to comparator groups in C1 (57 [119%] Vs 62 [128%]; p=0.696) or C2 (30 [226%] Vs 35 [276%]; p=0.391), despite elevated antibody titers, suggesting that protection did not extend to 5 years after vaccination. This is in contrast to the earlier assessment of parasitemia in C1, where a 34% lower prevalence of parasitemia was observed in the RTS,S/AS02 group at month 45. Comparison with other Phase II trials highlights a complex relationship between efficacy, age and transmission intensity. RTS,S/AS02 provided partial protection from clinical malaria for at least 3.5 years in C1. Duration of protection may depend on environmental circumstances, such as changing malaria transmission, and special attention should be given in the Phase III trial to identifying factors that modify longevity of protection.
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Antigenicity and immunogenicity of a novel Plasmodium vivax circumsporozoite derived synthetic vaccine construct.
Vaccine
PUBLISHED: 01-20-2014
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The circumsporozoite (CS) protein is a major malaria sporozoite surface antigen currently being considered as vaccine candidate. Plasmodium vivax CS (PvCS) protein comprises a dimorphic central repeat fragment flanked by conserved regions that contain functional domains involved in parasite invasion of host cells. The protein amino (N-terminal) flank has a cleavage region (region I), essential for proteolytic processing prior to parasite invasion of liver cells.
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Blood oxidative stress markers and Plasmodium falciparum malaria in non-immune African children.
Br. J. Haematol.
PUBLISHED: 01-16-2014
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Converging in vitro evidence and clinical data indicate that oxidative stress may play important roles in Plasmodium falciparum malaria, notably in the pathogenesis of severe anaemia. However, oxidative modifications of the red blood cell (RBC)-membrane by 4-hydroxynonenal (4-HNE) and haemoglobin-binding, previously hypothesized to contribute mechanistically to the pathogenesis of clinical malaria, have not yet been tested for clinical significance. In 349 non-immune Mozambican newborns recruited in a double-blind placebo-controlled chemoprophylaxis trial, oxidative markers including 4-HNE-conjugates and membrane-bound haemoglobin were longitudinally assessed from 2·5 to 24 months of age, at first acute malaria episode and in convalescence. During acute malaria, 4-HNE-conjugates were shown to increase significantly in parasitized and non-parasitized RBCs. In parallel, advanced oxidation protein products (AOPP) rose in plasma. 4-HNE-conjugates correlated with AOPP and established plasma but not with RBC oxidative markers. High individual levels of 4-HNE-conjugates were predictive for increased malaria incidence rates in children until 2 years of life and elevated 4-HNE-conjugates in convalescence accompanied sustained anaemia after a malaria episode, indicating 4-HNE-conjugates as a novel patho-mechanistic factor in malaria. A second oxidative marker, haemoglobin binding to RBC-membranes, hypothesized to induce clearing of RBCs from circulation, was predictive for lower malaria incidence rates. Further studies will show whether or not higher membrane-haemoglobin values at the first malaria episode may provide protection against malaria.
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Severity of anaemia is associated with bone marrow haemozoin in children exposed to Plasmodium falciparum.
Br. J. Haematol.
PUBLISHED: 01-06-2014
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There are no large-scale ex vivo studies addressing the contribution of Plasmodium falciparum in the bone marrow to anaemia. The presence of malaria parasites and haemozoin were studied in bone marrows from 290 anaemic children attending a rural hospital in Mozambique. Peripheral blood infections were determined by microscopy and polymerase chain reactions. Bone marrow parasitaemia, haemozoin and dyserythropoiesis were microscopically assessed. Forty-two percent (123/290) of children had parasites in the bone marrow and 49% (111/226) had haemozoin, overlapping with parasitaemia in 83% (92/111) of cases. Sexual and mature asexual parasites were highly prevalent (62% gametocytes, 71% trophozoites, 23% schizonts) suggesting their sequestration in this tissue. Sixteen percent (19/120) of children without peripheral infection had haemozoin in the bone marrow. Haemozoin in the bone marrow was independently associated with decreased Hb concentration (P = 0·005) and was more common in dyserythropoietic bone marrows (P = 0·010). The results of this ex vivo study suggest that haemozoin in the bone marrow has a role in the pathogenesis of malarial-anaemia through ineffective erythropoiesis. This finding may have clinical implications for the development of drugs targeted to prevent and treat malarial-anaemia.
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Molecular evidence for the localization of Plasmodium falciparum immature gametocytes in the bone marrow.
Blood
PUBLISHED: 12-13-2013
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Plasmodium falciparum immature gametocytes are not observed in peripheral blood. However, gametocyte stages in organs such as the bone marrow have never been assessed by molecular techniques with increased sensitivities than optical microscopy. We quantified P. falciparum sexual stages in bone marrow (n=174) and peripheral blood (n=70) of Mozambican anemic children by quantitative polymerase chain reaction (qPCR) targeting transcripts specific for early (PF14_0748; PHISTa), intermediate (PF13_0247; Pfs48/45) and mature (PF10_0303; Pfs25) gametocytes. Among children positive for the P. falciparum housekeeping gene (PF08_0085; ubiquitin-conjugating enzyme gene) in bone marrow (n=136) and peripheral blood (n=25), prevalence of immature gametocytes was higher in bone marrow than peripheral blood (early: 95% versus 20%, p<0.001; and intermediate: 80% versus 16%; p<0.001), as were transcript levels (p<0.001 for both stages). In contrast, mature gametocytes were more prevalent (100% versus 51%, p<0.001) and abundant (p<0.001) in peripheral blood than in the bone marrow. Severe anemia (3.57, 95%CI[1.49-8.53]) and dyserythropoiesis (6.21, 95%CI[2.24-17.25]) were independently associated with a higher prevalence of mature gametocytes in bone marrow. Our results highlight the high prevalence and abundance of early sexual stages in bone marrow, as well as a relationship between hematological disturbances and gametocyte development in this tissue.
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Colonic diverticular bleeding: Urgent colonoscopy without purging and endoscopic treatment with epinephrine and hemoclips.
Rev Esp Enferm Dig
PUBLISHED: 11-27-2013
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Diverticular disease is the most frequent cause of lower gastrointestinal bleeding. Most of the times, bleeding stops without any intervention but in 10-20 % of the cases it is necessary to treat the hemorrhage. Several modalities of endoscopic treatment have been described after purging the colon. We present five cases of severe diverticular bleeding treated with injection of epinephrine and hemoclips. All the colonoscopies were performed without purging of the colon in an emergency setting, with correct visualization of the point of bleeding. Patients recovered well avoiding other aggressive procedures such as angiography or surgery.
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Profile: Manhiça Health Research Centre (Manhiça HDSS).
Int J Epidemiol
PUBLISHED: 10-26-2013
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The Manhiça Health Research Centre, established in 1996 in a rural area of southern Mozambique, currently follows around 92 000 individuals living in approximately 20 000 enumerated and geo-positioned households. Its main strength is the possibility of linking demographic data and clinical data to promote and conduct biomedical research in priority health areas. Socio-demographic data are updated twice a year and clinical data are collected on a daily basis. The data collected in Manhiça HDSS comprises household and individual characteristics, household socio-economic assets, vital data, migration, individual health history and cause of death, among others. Studies conducted in this HDSS contributed to guide the health authorities and decision-making bodies to define or adjust health policies such as the introduction of Mozambiques expanded programme of immunization with different vaccines (Haemophilus influenzae type b, Pneumococcus) or the development of the concept of Intermittent Preventive Treatment for Infants (IPTi) that led to the World Health Organization recommendation of this method as best practice for the control of malaria among infants. Manhiças data can be accessed through a formal request to Diana Quelhas (diana.quelhas@manhica.net) accompanied by a proposal that will be analysed by the Manhiça HDSS internal scientific and ethics committees.
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Age differences in hippocampus-cortex connectivity during true and false memory retrieval.
J Int Neuropsychol Soc
PUBLISHED: 09-23-2013
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The present functional magnetic resonance imaging (fMRI) study investigated developmental differences in functional connectivity associated with true and false memory retrieval. A sample of 8- to 9-year-olds and adults (N = 31) was assessed with the Deese/Roediger-McDermott (DRM) paradigm, known to induce high levels of false recognition of lures that are semantically associated with studied items. The strength of semantic association among list items was manipulated. Relative to children, adults correctly recognized more studied items and falsely recognized more critical lures. High-association lists resulted in higher recognition of both studied items and critical lures. Functional connectivity analysis revealed that, overall, true recognition was supported by coupling within two hippocampal-temporal and fronto-parietal set of regions; in contrast, coupling among more distributed hippocampal-temporal-parietal-frontal regions was observed during false recognition. Critically, adults, compared to children, exhibited stronger hippocampal/parietal coupling and stronger hippocampal/dorsolateral prefrontal cortex (PFC) coupling for veridical recognition of high-associative strength items. In contrast, children, compared to adults, exhibited stronger hippocampus/ventrolateral PFC coupling and stronger bilateral middle-temporal gyrus/ventrolateral PFC coupling for high-associative strength critical lures. Our results underscored a role for the anterior hippocampus in true and false recognition, showing different functional patterns as a function of age and association strength.
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Timeliness and completeness of vaccination and risk factors for low and late vaccine uptake in young children living in rural southern Tanzania.
Int Health
PUBLISHED: 09-14-2013
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We studied coverage and timeliness of vaccination and risk factors for low and delayed vaccine uptake in children aged <2 years in rural Tanzania.
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Adult eyewitness memory and compliance: effects of post-event misinformation on memory for a negative event.
Behav Sci Law
PUBLISHED: 06-30-2013
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This study investigated effects of misleading post-event information, delay, and centrality definition on eyewitness memory and suggestibility for a negative event (a vividly filmed murder). Either immediately or 2 weeks after viewing the film, 93 adults read a (misleading or control) narrative about the event and then completed a recognition memory test. Misinformation acceptance was operative, but strong evidence for memory malleability was lacking. Compliance predicted misinformation effects, especially on the delayed test. Although accuracy was generally higher for central than peripheral information, centrality criteria influenced the pattern of results. Self-report of greater distress was associated with better recognition accuracy. The results suggest that use of different centrality definitions may partly explain inconsistencies across studies of memory and suggestibility for central and peripheral information. Moreover, social factors appeared, at least in part, to influence misinformation effects for the highly negative event, especially as memory faded. Implications for eyewitness memory and suggestibility are discussed.
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Haemophilus influenzae type b disease among children in rural Mozambique: impact of vaccine introduction.
J. Pediatr.
PUBLISHED: 06-19-2013
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Haemophilus influenzae type b (Hib) conjugate vaccine has dramatically reduced invasive Hib disease worldwide. Yet, data on protection against pneumonia and among children with HIV are limited. We evaluated the impact of Hib conjugate vaccine introduction in 2009 in a rural, high-HIV prevalence area in Mozambique.
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Staphylococcal disease in Africa: another neglected tropical disease.
Future Microbiol
PUBLISHED: 06-08-2013
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The term neglected tropical diseases predominantly refers to single-entity, mostly parasitic diseases. However, a considerable morbidity and mortality burden is carried by patients infected with Gram-positive cocci and Gram-negative bacilli that are prevalent all over the world, yet have impact in tropical and developing countries, particularly in children, with much higher incidence rates than those reported from developed countries. Staphylococcus aureus is among these pathogens. The African-German StaphNet consortium uses microbiological characterization of African S. aureus isolates, including identification of virulence factors, alongside the gathering of epidemiological and clinical data in an innovative research network between a European country (Germany) and several African partners. By creating an accessible strain repository and by implementing personnel training and capacity building, this network aims to put staphylococcal disease on the international agenda as a truly neglected condition with a major global impact on public health.
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[Treatment for cancer pain at the end of life: a case study in a palliative care service in the Autonomous City of Buenos Aires].
Salud Colect
PUBLISHED: 05-18-2013
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Cancer pain relief has been defined as a worldwide public health challenge in the last decades and has recently been included in public debates as a human rights issue. However, barriers to the provision of adequate pain management continue to exist. This article analyzes the cancer pain treatment provided in a palliative care setting in the Autonomous City of Buenos Aires, focusing on how professionals and patients implement and negotiate the terms and adherence to the pain treatment. Based on a qualitative approach that triangulates data from semi-structured interviews and from ethnographic observations, the article addresses the way pain is measured and assessed and the strategies of health professionals in establishing pain treatment protocols. The article also describes the rhetoric regarding the right to pain relief developed by health professionals through their practice and discusses the limitations of that rhetoric.
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Severe malnutrition among children under the age of 5 years admitted to a rural district hospital in southern Mozambique.
Public Health Nutr
PUBLISHED: 05-02-2013
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To describe the burden, clinical characteristics and prognostic factors of severe malnutrition in children under the age of 5 years.
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[Palliative care: between humanization and medicalization at the end of life].
Cien Saude Colet
PUBLISHED: 04-30-2013
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This paper analyzes the palliative care of terminal patients, examining the tensions between the humanization of care and the progressive medicalization at the end-of-life situation. The research upon which the article is based adopts a qualitative methodological approach derived from interviews with professionals and patients and ethnographic observations in a palliative care unit in the City of Buenos Aires, Argentina. The article describes the configuration of personalized and comprehensive health care based on the core values of more humanized end-of-life care promoted by palliative care supporters. Similarly, the paper analyzes how these practices are assisted by progress in the medicalization process in which the dimension of care is considered less an unprofessional area of medical practice than an area of care in which specific technical skills and know-how are employed. The articles explores how instead of being divergent, the logic of care and medicalization work in a complementary fashion.
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Health care seeking for childhood diarrhea in developing countries: evidence from seven sites in Africa and Asia.
Am. J. Trop. Med. Hyg.
PUBLISHED: 04-29-2013
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We performed serial Health Care Utilization and Attitudes Surveys (HUASs) among caretakers of children ages 0-59 months randomly selected from demographically defined populations participating in the Global Enteric Multicenter Study (GEMS), a case-control study of moderate-to-severe diarrhea (MSD) in seven developing countries. The surveys aimed to estimate the proportion of children with MSD who would present to sentinel health centers (SHCs) where GEMS case recruitment would occur and provide a basis for adjusting disease incidence rates to include cases not seen at the SHCs. The proportion of children at each site reported to have had an incident episode of MSD during the 7 days preceding the survey ranged from 0.7% to 4.4% for infants (0-11 months of age), from 0.4% to 4.7% for toddlers (12-23 months of age), and from 0.3% to 2.4% for preschoolers (24-59 months of age). The proportion of MSD episodes at each site taken to an SHC within 7 days of diarrhea onset was 15-56%, 17-64%, and 7-33% in the three age strata, respectively. High cost of care and insufficient knowledge about danger signs were associated with lack of any care-seeking outside the home. Most children were not offered recommended fluids and continuing feeds at home. We have shown the utility of serial HUASs as a tool for optimizing operational and methodological issues related to the performance of a large case-control study and deriving population-based incidence rates of MSD. Moreover, the surveys suggest key targets for educational interventions that might improve the outcome of diarrheal diseases in low-resource settings.
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Health care utilization and attitudes survey in cases of moderate-to-severe diarrhea among children ages 0-59 months in the District of Manhica, southern Mozambique.
Am. J. Trop. Med. Hyg.
PUBLISHED: 04-29-2013
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In the predominantly rural Manhiça district, in southern Mozambique, diarrhea is one of the leading causes of death among children under 5 years. Caretakers randomly selected from the Demographic Surveillance Database were invited to participate in a community-based survey on use of healthcare services for gastroenteritis. Of those caretakers reporting an episode of diarrhea during the recall period, 65.2% in the first survey and 43.8% in the second survey reported seeking care at a health facility. Independent risk factors for seeking care in health facilities in the first survey included the presence of diarrhea with fever and not knowing any sign of dehydration; having a television at home was related with an independent decreased use of the health facilities. In the second survey, the use of health services was significantly associated with diarrhea with fever and vomiting. Establishment of continuous prospective monitoring allows accounting for changes in healthcare use that may occur because of seasonality or secular events.
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Semantic processes leading to true and false memory formation in schizophrenia.
Schizophr. Res.
PUBLISHED: 04-05-2013
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Encoding semantic relationships between items on word lists (semantic processing) enhances true memories, but also increases memory distortions. Episodic memory impairments in schizophrenia (SZ) are strongly driven by failures to process semantic relations, but the exact nature of these relational semantic processing deficits is not well understood. Here, we used a false memory paradigm to investigate the impact of implicit and explicit semantic processing manipulations on episodic memory in SZ. Thirty SZ and 30 demographically matched healthy controls (HC) studied Deese/Roediger-McDermott (DRM) lists of semantically associated words. Half of the lists had strong implicit semantic associations and the remainder had low strength associations. Similarly, half of the lists were presented under "standard" instructions and the other half under explicit "relational processing" instructions. After study, participants performed recall and old/new recognition tests composed of targets, critical lures, and unrelated lures. HC exhibited higher true memories and better discriminability between true and false memory compared to SZ. High, versus low, associative strength increased false memory rates in both groups. However, explicit "relational processing" instructions positively improved true memory rates only in HC. Finally, true and false memory rates were associated with severity of disorganized and negative symptoms in SZ. These results suggest that reduced processing of semantic relationships during encoding in SZ may stem from an inability to implement explicit relational processing strategies rather than a fundamental deficit in the implicit activation and retrieval of word meanings from patients semantic lexicon.
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Strength of Coupling within a mnemonic control network differentiates those who can and cannot suppress memory retrieval.
J. Neurosci.
PUBLISHED: 03-15-2013
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The ability to direct our thought processes influences not only what we do, but also what we remember later. Here we sought to identify the brain network that supports the ability to control memory retrieval and to understand the neural basis of age-related changes and individual differences in the capacity for mnemonic control. To this end, we collected functional MRI data from 43 children and young adults while they attempted to retrieve or suppress retrieval of previously learned associations. Seed-based functional connectivity analyses revealed a largely right-lateralized dorsolateral prefrontal cortex-cingulate-parietal-hippocampal network that exhibited strongly correlated activity during retrieval suppression. Regardless of age, individuals who were able to suppress memory retrieval exhibited tighter coupling between key nodes in this dorsolateral prefrontal cortex-cingulate-parietal-hippocampal network than individuals who did not. Further, only those capable of mnemonic control exhibited tighter coupling during successful retrieval suppression (intentional forgetting) than during unsuccessful retrieval (unintentional forgetting). Across both children and adults, individual differences in retrieval suppression were best explained by the strength of these network interactions.
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Ivermectin to reduce malaria transmission: a research agenda for a promising new tool for elimination.
Malar. J.
PUBLISHED: 03-01-2013
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The heterogeneity of malaria transmission makes widespread elimination a difficult goal to achieve. Most of the current vector control measures insufficiently target outdoor transmission. Also, insecticide resistance threatens to diminish the efficacy of the most prevalent measures, indoor residual spray and insecticide treated nets. Innovative approaches are needed. The use of endectocides, such as ivermectin, could be an important new addition to the toolbox of anti-malarial measures. Ivermectin effectively targets outdoor transmission, has a novel mechanism of action that could circumvent resistance and might be distributed over the channels already in place for the control of onchocerciasis and lymphatic filariasis.
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Improved pregnancy outcomes in women exposed to malaria with high antibody levels against Plasmodium falciparum.
J. Infect. Dis.
PUBLISHED: 02-28-2013
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Antibodies against VAR2CSA, the Plasmodium falciparum variant surface antigen that binds placental chondroitin sulfate A, have been suggested to mediate protection against malaria in pregnancy but also to be markers of infection. Here, we aimed to identify clinically relevant antibody responses, taking into consideration variations in parasite exposure and human immunodeficiency virus type 1 (HIV) infection status.
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Public health challenges and prospects for malaria control and elimination.
Nat. Med.
PUBLISHED: 02-06-2013
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The past decade witnessed unprecedented efforts to control malaria, including renewed political and financial commitment and increased availability of both old and new strategies and tools. However, malaria still represents a major health burden, particularly in Africa. Important challenges such as the fragility of many health systems, the rise of insecticide and drug resistance, and particularly the expected decline both in funding and in the coverage of key interventions if they are not replaced as needed, urgently need to be addressed. Further research and development is also becoming increasingly crucial. Among other needs, common methodologies for estimating and tracking the malaria burden, new strategies to measure transmission, better understanding of immunity, and increased knowledge of the mechanisms and effects of resistance to drugs and insecticides stand out. The ongoing efforts in research and development for new antimalarial drugs, more sensitive point-of-care rapid diagnostic tests and new insecticides need further innovation and substantial strengthening. Clearly, efforts should focus not only on Plasmodium falciparum but also and increasingly on Plasmodium vivax, the neglected human malaria parasite. Addressing these challenges in a comprehensive and timely way will allow us to sustain the gains made so far and make further progress in control and progressive elimination.
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Breast Milk and Gut Microbiota in African Mothers and Infants from an Area of High HIV Prevalence.
PLoS ONE
PUBLISHED: 01-01-2013
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Human milk and infant gut microbiota are essential for the immune system maturation and protection against infections. There is scarce information on the microbiological composition of breast milk in general, and none from developing countries. The objective of the study was to characterize the breast milk and gut microbiota from mothers and infants from southern Mozambique, where infections and breastfeeding are prevalent.
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High antibody responses against Plasmodium falciparum in immigrants after extended periods of interrupted exposure to malaria.
PLoS ONE
PUBLISHED: 01-01-2013
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Malaria immunity is commonly believed to wane in the absence of Plasmodium falciparum exposure, based on limited epidemiological data and short-lived antibody responses in some longitudinal studies in endemic areas.
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VAR2CSA signatures of high Plasmodium falciparum parasitemia in the placenta.
PLoS ONE
PUBLISHED: 01-01-2013
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Plasmodium falciparum infected erythrocytes (IE) accumulate in the placenta through the interaction between Duffy-binding like (DBL) domains of parasite-encoded ligand VAR2CSA and chondroitin sulphate-A (CSA) receptor. Polymorphisms in these domains, including DBL2X and DBL3X, may affect their antigenicity or CSA-binding affinity, eventually increasing parasitemia and its adverse effects on pregnancy outcomes. A total of 373 DBL2X and 328 DBL3X sequences were obtained from transcripts of 20 placental isolates infecting Mozambican women, resulting in 176 DBL2X and 191 DBL3X unique sequences at the protein level. Sequence alignments were divided in segments containing combinations of correlated polymorphisms and the association of segment sequences with placental parasite density was tested using Bonferroni corrected regression models, taking into consideration the weight of each sequence in the infection. Three DBL2X and three DBL3X segments contained signatures of high parasite density (P<0.003) that were highly prevalent in the parasite population (49-91%). Identified regions included a flexible loop that contributes to DBL3X-CSA interaction and two DBL3X motifs with evidence of positive natural selection. Limited antibody responses against signatures of high parasite density among malaria-exposed pregnant women could not explain the increased placental parasitemia. These results suggest that a higher binding efficiency to CSA rather than reduced antigenicity might provide a biological advantage to parasites with high parasite density signatures in VAR2CSA. Sequences contributing to high parasitemia may be critical for the functional characterization of VAR2CSA and the development of tools against placental malaria.
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Lower respiratory tract infections associated with rhinovirus during infancy and increased risk of wheezing during childhood. A cohort study.
PLoS ONE
PUBLISHED: 01-01-2013
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Although association between respiratory syncytial virus infection and later asthma development has been established, little is known about the role of other respiratory viruses. Rhinovirus was considered a mild pathogen of the upper respiratory tract but current evidence suggests that rhinovirus is highly prevalent among children with lower respiratory tract infections (LRTI). The aim of the study was to evaluate whether LRTI hospitalization associated with rhinovirus during infancy was associated with an increased risk of wheezing - a proxy measure of asthma - during childhood.
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Age-dependent IgG subclass responses to Plasmodium falciparum EBA-175 are differentially associated with incidence of malaria in Mozambican children.
Clin. Vaccine Immunol.
PUBLISHED: 12-14-2011
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Plasmodium falciparum blood-stage antigens such as merozoite surface protein 1 (MSP-1), apical membrane antigen 1 (AMA-1), and the 175-kDa erythrocyte binding antigen (EBA-175) are considered important targets of naturally acquired immunity to malaria. However, it is not clear whether antibodies to these antigens are effectors in protection against clinical disease or mere markers of exposure. In the context of a randomized, placebo-controlled trial of intermittent preventive treatment in infants conducted between 2002 and 2004, antibody responses to Plasmodium falciparum blood-stage antigens in a cohort of 302 Mozambican children were evaluated by immunofluorescence antibody test and enzyme-linked immunosorbent assay at 5, 9, 12, and 24 months of age. We found that IgG subclass responses to EBA-175 were differentially associated with the incidence of malaria in the follow-up period. A double amount of cytophilic IgG1 or IgG3 was associated with a significant decrease in the incidence of malaria (incidence rate ratio [IRR] = 0.49, 95% confidence interval [CI] = 0.25 to 0.97, and P = 0.026 and IRR = 0.44, CI = 0.19 to 0.98, and P = 0.037, respectively), while a double amount of noncytophilic IgG4 was significantly correlated with an increased incidence of malaria (IRR = 3.07, CI = 1.08 to 8.78, P = 0.020). No significant associations between antibodies to the 19-kDa fragment of MSP-1 (MSP-1(19)) or AMA-1 and incidence of malaria were found. Age, previous episodes of malaria, present infection, and neighborhood of residence were the main factors influencing levels of antibodies to all merozoite antigens. Deeper understanding of the acquisition of antibodies against vaccine target antigens in early infancy is crucial for the rational development and deployment of malaria control tools in this vulnerable population.
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First results of phase 3 trial of RTS,S/AS01 malaria vaccine in African children.
Selidji Todagbe Agnandji, Bertrand Lell, Solange Solmeheim Soulanoudjingar, José Francisco Fernandes, Béatrice Peggy Abossolo, Cornelia Conzelmann, Barbara Gaelle Nfono Ondo Methogo, Yannick Doucka, Arnaud Flamen, Benjamin Mordmüller, Saadou Issifou, Peter Gottfried Kremsner, Jahit Sacarlal, Pedro Aide, Miguel Lanaspa, John J Aponte, Arlindo Nhamuave, Diana Quelhas, Quique Bassat, Sofia Mandjate, Eusébio Macete, Pedro Alonso, Salim Abdulla, Nahya Salim, Omar Juma, Mwanajaa Shomari, Kafuruki Shubis, Francisca Machera, Ali Said Hamad, Rose Minja, Ali Mtoro, Alma Sykes, Saumu Ahmed, Alwisa Martin Urassa, Ali Mohammed Ali, Grace Mwangoka, Marcel Tanner, Halidou Tinto, Umberto D'Alessandro, Hermann Sorgho, Innocent Valea, Marc Christian Tahita, William Kaboré, Sayouba Ouédraogo, Yara Sandrine, Robert Tinga Guiguemdé, Jean Bosco Ouédraogo, Mary J Hamel, Simon Kariuki, Chris Odero, Martina Oneko, Kephas Otieno, Norbert Awino, Jackton Omoto, John Williamson, Vincent Muturi-Kioi, Kayla F Laserson, Laurence Slutsker, Walter Otieno, Lucas Otieno, Otsyula Nekoye, Stacey Gondi, Allan Otieno, Bernhards Ogutu, Ruth Wasuna, Victorine Owira, David Jones, Agnes Akoth Onyango, Patricia Njuguna, Roma Chilengi, Pauline Akoo, Christine Kerubo, Jesse Gitaka, Charity Maingi, Trudie Lang, Ally Olotu, Benjamin Tsofa, Philip Bejon, Norbert Peshu, Kevin Marsh, Seth Owusu-Agyei, Kwaku Poku Asante, Kingsley Osei-Kwakye, Owusu Boahen, Samuel Ayamba, Kingsley Kayan, Ruth Owusu-Ofori, David Dosoo, Isaac Asante, George Adjei, Daniel Chandramohan, Brian Greenwood, John Lusingu, Samwel Gesase, Anangisye Malabeja, Omari Abdul, Hassan Kilavo, Coline Mahende, Edwin Liheluka, Martha Lemnge, Thor Theander, Chris Drakeley, Daniel Ansong, Tsiri Agbenyega, Samuel Adjei, Harry Owusu Boateng, Theresa Rettig, John Bawa, Justice Sylverken, David Sambian, Alex Agyekum, Larko Owusu, Francis Martinson, Irving Hoffman, Tisungane Mvalo, Portia Kamthunzi, Ruthendo Nkomo, Albans Msika, Allan Jumbe, Nelecy Chome, Dalitso Nyakuipa, Joseph Chintedza, W Ripley Ballou, Myriam Bruls, Joe Cohen, Yolanda Guerra, Erik Jongert, Didier Lapierre, Amanda Leach, Marc Lievens, Opokua Ofori-Anyinam, Johan Vekemans, Terrell Carter, Didier Leboulleux, Christian Loucq, Afiya Radford, Barbara Savarese, David Schellenberg, Marla Sillman, Preeti Vansadia, .
N. Engl. J. Med.
PUBLISHED: 10-18-2011
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An ongoing phase 3 study of the efficacy, safety, and immunogenicity of candidate malaria vaccine RTS,S/AS01 is being conducted in seven African countries.
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Alterations in T cell subsets in human immunodeficiency virus-infected adults with co-infections in southern Mozambique.
Am. J. Trop. Med. Hyg.
PUBLISHED: 10-07-2011
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T cell activation and depletion of naive T cells are hallmarks of human immunodeficiency virus (HIV) pathogenesis. This study explored the relationships between certain co-infections (including syphilis, hepatitis B and C, human T cell lymphotrophic viruses I and II [HTLV-I/II], Kaposi sarcoma-associated herpesvirus [KSHV], Plasmodium falciparum malaria, and tuberculosis), and levels of activated CD8 and CD4 T cell subsets as well as naive and memory CD4 T cells in HIV-infected adults in a rural area of southern Mozambique. We found that syphilis infection and to a lesser extent HTLV-I/II seropositivity were independently associated with higher CD8 T cell activation (CD8+ CD38+ HLA-DR+) whereas only syphilis was associated with higher CD4 T cell activation. Furthermore, KSHV and HTLV-I/II seropositivities were independently associated with a lower percentage of naive CD4 T cells (CD4+ CD45RA+ CD62L+). These results highlight the importance of screening and prompt treatment of syphilis, and raise questions as to whether HIV-positive persons with certain chronic viral co-infections should initiate combined antiretroviral therapy at higher CD4 cell counts.
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Distinguishing malaria from severe pneumonia among hospitalized children who fulfilled integrated management of childhood illness criteria for both diseases: a hospital-based study in Mozambique.
Am. J. Trop. Med. Hyg.
PUBLISHED: 10-07-2011
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Malaria and severe pneumonia in hospitalized young children may show striking clinical similarities, making differential diagnosis challenging. We investigated ways to increase diagnostic accuracy in patients hospitalized with clinical symptoms compatible with malaria and severe pneumonia, in an area with high a prevalence of infection with human immunodeficiency virus. A total of 646 children admitted at the Manhiça District Hospital in Manhiça, Mozambique who met the World Health Organization clinical criteria for severe pneumonia and malaria were recruited for 12 months and thoroughly investigated to ascertain an accurate diagnosis. Although symptom overlap between malaria and severe pneumonia was frequent among hospitalized children, true disease overlap was uncommon. Clinical presentation and laboratory determinations were ineffective in reliably distinguishing between the two diseases. Infection with human immunodeficiency virus differentially influenced the epidemiology and clinical presentation of these two infectious diseases, further challenging their discrimination on clinical grounds, and having a greater impact on the current burden and prognosis of severe pneumonia.
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Development of vaccines to prevent malaria in pregnant women: WHO MALVAC meeting report.
Expert Rev Vaccines
PUBLISHED: 09-17-2011
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The major public health consequences of malaria in pregnancy have long been acknowledged. However, further information is still required for development and implementation of a malaria vaccine specifically directed to prevent malaria in pregnant women and improve maternal, fetal and infant outcomes. The WHO Malaria Vaccine Advisory Committee (MALVAC) provides guidance to the WHO on strategic priorities and research needs for development of vaccines to prevent malaria. Here we summarize the discussions and conclusions of a MALVAC scientific forum meeting on considerations in the development of vaccines to prevent malaria in pregnant women. This report includes brief summaries of what is known, and major knowledge gaps in disease burden estimation, pathogenesis and immunity, and the challenges with current preventive strategies for malaria in pregnancy. We conclude with the formulation of a conceptual framework for research and development for vaccines to prevent malaria in pregnant women.
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Safety of sulfadoxine/pyrimethamine for intermittent preventive treatment of malaria in infants: evidence from large-scale operational research in southern Tanzania.
Int Health
PUBLISHED: 09-01-2011
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Intermittent preventive treatment with sulfadoxine/pyrimethamine (SP) is recommended for malaria prevention in infants (IPTi-SP). Serious adverse events, including Stevens-Johnson syndrome (SJS), have been reported following exposure to SP, but few infant-specific data exist. The safety of IPTi-SP was evaluated as part of a pilot implementation programme in southern Tanzania using three methods: spontaneous adverse event reporting to capture suspected adverse drug reactions (ADR); a census survey documenting rash-related hospital admissions among children < 2 years of age; and verbal autopsies (VA) completed for rash-related deaths in 2-11-month-olds. Approximately 82 000 IPTi-SP doses were administered to approximately 29 000 children. In total, 119 suspected ADRs were reported, 13 in children aged <2 years, only one of whom had received IPTi-SP. The census involved 243 612 households. Only one rash-related admission was reported amongst 1292 children aged 2-11 months, but this child had no history of exposure to SP. Moreover, 30 of 699 deaths in 2-11-month-olds were said to have been associated with a skin rash. The rates of rash-associated death were 0.59/1000 person-years at risk (PYAR) and 1.17/1000 PYAR in intervention and comparison areas, respectively (P = 0.79). VAs did not suggest SJS or any other ADR. We conclude that IPTi-SP is associated with a very low incidence of severe skin reactions. [ClinicalTrials.gov identifier: NCT00152204].
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Cluster-randomized study of intermittent preventive treatment for malaria in infants (IPTi) in southern Tanzania: evaluation of impact on survival.
Malar. J.
PUBLISHED: 07-26-2011
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Intermittent Preventive Treatment for malaria control in infants (IPTi) consists of the administration of a treatment dose of an anti-malarial drug, usually sulphadoxine-pyrimethamine, at scheduled intervals, regardless of the presence of Plasmodium falciparum infection. A pooled analysis of individually randomized trials reported that IPTi reduced clinical episodes by 30%. This study evaluated the effect of IPTi on child survival in the context of a five-district implementation project in southern Tanzania. [Trial registration: clinical trials.gov NCT00152204].
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Costs associated with low birth weight in a rural area of Southern Mozambique.
PLoS ONE
PUBLISHED: 07-26-2011
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Low Birth Weight (LBW) is prevalent in low-income countries. Even though the economic evaluation of interventions to reduce this burden is essential to guide health policies, data on costs associated with LBW are scarce. This study aims to estimate the costs to the health system and to the household and the Disability Adjusted Life Years (DALYs) arising from infant deaths associated with LBW in Southern Mozambique.
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rTMS stimulation to induce plastic changes at the language motor area in a patient with a left recidivant brain tumor affecting Brocas area.
Neurocase
PUBLISHED: 07-25-2011
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Extent of resection is one of the most powerful predictors of outcome in surgery of gliomas. Tumors located within areas governing eloquence may impede a total tumor resection. Functional plasticity may be induced by therapeutic means, such as cortical stimulation with repetitive transcranial magnetic stimulation (rTMS). Thus, rTMS is a potential tool to induce an improvement of functions of eloquence menaced by brain tumors.
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Assessment of the epidemiology and burden of measles in Southern Mozambique.
Am. J. Trop. Med. Hyg.
PUBLISHED: 07-08-2011
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Measles has been a major killer among vaccine-preventable diseases in children < 5 years of age in developing countries. Despite progress in global efforts to reduce mortality, measles remains a public health problem. Hospital-based measles surveillance was conducted in Manhica, Mozambique (July 2001-September 2004). Suspected cases and community-based controls were enrolled, and blood was collected for immunoglobulin M (IgM) confirmation. Two hundred fifty-three suspected cases and 477 controls were enrolled, with 85% (216 of 253) cases reported during a measles outbreak. Measles-IgM confirmation was 30% among suspected cases and 5% in controls. Fifty-eight percent (14 of 24) of laboratory-confirmed cases had records indicating previous measles vaccination. Mortality was 3% (8 of 246) among cases and 1% among controls (6 of 426). Forty-five percent (33 of 74) of cases were < 24 months of age and 22% occurred in infants < 9 months of age and were associated with a high case-fatality rate (25%). Our data suggest that improved diagnostics, new tools to protect infants < 9 months of age, and a supplemental dose of measles vaccine could assist measles control.
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Viral acute respiratory infections among infants visited in a rural hospital of southern Mozambique.
Trop. Med. Int. Health
PUBLISHED: 06-28-2011
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To determine the epidemiology and clinical presentation of virus-associated acute respiratory infections (ARI) in Mozambican infants.
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What drives community adherence to indoor residual spraying (IRS) against malaria in Manhiça district, rural Mozambique: a qualitative study.
Malar. J.
PUBLISHED: 06-23-2011
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Malaria control remains a challenge in sub-Saharan Africa. In 2006, the World Health Organization (WHO) reinforced the recommendation of indoor residual spraying (IRS) with dichlorodiphenyltrichloroethane (DDT) to reduce malaria transmission. The National Malaria Control Programme has been reporting high coverage rates of IRS in Mozambique. It is important to establish to what extent these rates are a reflection of community acceptability, and to explore the factors associated with adherence, in order to recommend suitable approaches for interventions of this nature.
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Erythropoietin levels are not independently associated with malaria-attributable severe disease in Mozambican children.
PLoS ONE
PUBLISHED: 06-02-2011
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Severe malaria is difficult to differentiate from other forms of malaria or other infections with similar symptoms. Any parameter associated to malaria-attributable severe disease could help to improve severe malaria diagnosis.
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Transcription of var genes other than var2csa in Plasmodium falciparum parasites infecting Mozambican pregnant women.
J. Infect. Dis.
PUBLISHED: 06-02-2011
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Increased susceptibility to Plasmodium falciparum infection during pregnancy has been attributed to the accumulation of infected erythrocytes in the placenta. This phenomenon is mediated by a var gene coding for VAR2CSA, which adheres to chondroitin sulphate A. However, the contribution of parasites transcribing other var genes to maternal infections has not been well characterized.
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Impact of the RTS,S malaria vaccine candidate on naturally acquired antibody responses to multiple asexual blood stage antigens.
PLoS ONE
PUBLISHED: 04-14-2011
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Partial protective efficacy lasting up to 43 months after vaccination with the RTS,S malaria vaccine has been reported in one cohort (C1) of a Phase IIb trial in Mozambique, but waning efficacy was observed in a smaller contemporaneous cohort (C2). We hypothesized that low dose exposure to asexual stage parasites resulting from partial pre-erythrocytic protection afforded by RTS,S may contribute to long-term vaccine efficacy to clinical disease, which was not observed in C2 due to intense active detection of infection and treatment.
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Epidemiology, molecular characterization and antibiotic resistance of Neisseria meningitidis from patients ?15 years in Manhiça, rural Mozambique.
PLoS ONE
PUBLISHED: 04-14-2011
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The epidemiology of meningococcal disease in Mozambique and other African countries located outside the "meningitis belt" remains widely unknown. With the event of upcoming vaccines microbiological and epidemiological information is urgently needed.
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Pyrethroid use-malaria control and individual applications by households for other pests and home garden use.
Environ Int
PUBLISHED: 04-06-2011
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Presence of pyrethroid insecticides in human breast milk and in thatch wall material of dwellings from Southern Africa subtropical area (Manhiça, Mozambique) was investigated to assess potential pyrethroid route of human exposure. Human breast milk samples were collected during 2002 when pyrethroids were widely used as insecticides for mosquito bed nets in Mozambique for malaria control. The median concentration value of total pyrethroids ranged between 87 and 1200ng/glw, with ?-cyhalothrin being the most predominant pyrethroid in human breast milk contributing for 35% of the total amount. Moreover, and for the first time, an isomer-specific enrichment was found in human breast milk, showing a selective isomeric accumulation or metabolism in the human body. Based on the calculated pyrethroid concentrations in human breast milk, the daily ingestion rate of pyrethroid was estimated. The nursing infant dietary intake ranged from 0.67 to 9.0?g(kg of body weight)(-1)day(-1). In addition, thatch materials collected after the reintegration of dichlorodiphenyltrichloroethene (DDT) as insecticide residual spraying (IRS) in Mozambique, showed the presence of pyrethroids with concentration values ranging between 6.9 and 700ng/gdw. In thatch material as well as in human breast milk, pyrethroid contamination was mainly attributed to the agriculture usage of this insecticide knowing that agriculture represent the 80% of the economy in Mozambique. However, a possible usage of this insecticide as IRS in Mozambique cannot be excluded despite their low efficiency for malaria control. The continued use of these compounds (both for agriculture and malaria prevention) and the ingestion rates calculated from the breast milk concentrations indicate that these insecticides cannot be overlooked for the assessment of the lactation risks of breastfeeding infants from the Manhiça region.
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Association of severe malaria outcomes with platelet-mediated clumping and adhesion to a novel host receptor.
PLoS ONE
PUBLISHED: 04-02-2011
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Severe malaria has been attributed partly to the sequestration of Plasmodium falciparum-infected erythrocytes (IEs) in the microvasculature of vital host organs. Identification of P. falciparum cytoadherence phenotypes that are associated with severe malaria may lead to the development of novel strategies against life-threatening malaria.
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HIV and placental infection modulate the appearance of drug-resistant Plasmodium falciparum in pregnant women who receive intermittent preventive treatment.
Clin. Infect. Dis.
PUBLISHED: 03-29-2011
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Factors involved in the development of resistance to sulphadoxine-pyrimethamine (SP) by Plasmodium falciparum, particularly in the context of intermittent preventive treatment during pregnancy (IPTp), are not well known. We aimed to determine the impact of IPTp and human immunodeficiency virus (HIV) infection on molecular markers of SP resistance and the clinical relevance of resistant infections.
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Assessment of exposure to DDT and metabolites after indoor residual spraying through the analysis of thatch material from rural African dwellings.
Environ Sci Pollut Res Int
PUBLISHED: 03-21-2011
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We report on the analysis of 4,4-dichlorodiphenyltrichloroethane (4,4-DDT) and its metabolites in thatch and branch samples constituting the wall materials of dwellings from South African subtropical areas. This approach was used to assess the exposure to DDT in the residents of the dwellings after indoor residual spraying (IRS) following recommended sanitation practices against malaria vectors.
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Concentration of DDT compounds in breast milk from African women (Manhiça, Mozambique) at the early stages of domestic indoor spraying with this insecticide.
Chemosphere
PUBLISHED: 03-19-2011
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Breast milk concentrations of 4,4-DDT and its related compounds were studied in samples collected in 2002 and 2006 from two populations of mothers in Manhiça, Mozambique. The 2006 samples were obtained several months after implementation of indoor residual spraying (IRS) with DDT for malaria vector control in dwellings and those from 2002 were taken as reference prior to DDT use. A significant increase in 4,4-DDT and its main metabolite, 4,4-DDE, was observed between the 2002 (median values 2.4 and 0.9 ng/ml, respectively) and the 2006 samples (7.3 and 2.6 ng/ml, respectively, p<0.001 and 0.019, respectively). This observation identifies higher body burden intakes of these compounds in pregnant women already in these initial stages of the IRS program. The increase in both 4,4-DDT and 4,4-DDE suggest a rapid transformation of DDT into DDE after incorporation of the insecticide residues. The median baseline concentrations in breast milk in 2002 were low, and the median concentrations in 2006 (280 ng/g lipid) were still lower than in other world populations. However, the observed increases were not uniform and in some individuals high values (5100 ng/g lipid) were determined. Significant differences were found between the concentrations of DDT and related compounds in breast milk according to parity, with higher concentrations in primiparae than multiparae women. These differences overcome the age effect in DDT accumulation between the two groups and evidence that women transfer a significant proportion of their body burden of DDT and its metabolites to their infants.
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Four year immunogenicity of the RTS,S/AS02(A) malaria vaccine in Mozambican children during a phase IIb trial.
Vaccine
PUBLISHED: 03-09-2011
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Previous studies with the malaria vaccine RTS,S/AS02(A) in young children in a malaria endemic area of Mozambique have shown it to have a promising safety profile and to reduce the risk of Plasmodium falciparum infection and disease. In this study, we assessed the antibody responses to the P. falciparum and hepatitis B components of the RTS,S/AS02(A) vaccine over a 45 months surveillance period in a large phase IIb trial which included 2022 children aged 1-4 years at recruitment. The RTS,S/AS02(A) vaccine induced high anti-circumsporozoite antibody levels with at least 96% of children remaining seropositive during the entire follow-up period. IgG titers decayed over the first 6 months of follow-up to about 25% of the initial level, but still remained 30-fold higher until month 45 compared to controls. Children with higher levels of naturally acquired immunity at baseline, assessed by blood stage indirect fluorescent antibody test, had slightly higher anti-circumsporozoite levels, after adjusting for the effect of age. The RTS,S/AS02(A) vaccine also induced high levels of anti-hepatitis B surface antigen antibodies (seroprotection >97%). RTS,S/AS02(A) vaccine is immunogenic and induces long-lasting anti-circumsporozoite antibodies, persisting at least 42 months after immunization. These antibodies may play a role in protection against malaria.
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Comparison of commercial kits to measure cytokine responses to Plasmodium falciparum by multiplex microsphere suspension array technology.
Malar. J.
PUBLISHED: 03-08-2011
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Multiplex cytokine profiling systems are useful tools for investigating correlates of protective immunity. Several Luminex and flow cytometry methods are commercially available but there is limited information on the relative performance of different kits. A series of comparison experiments were carried out to determine the most appropriate method for our subsequent studies.
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[Paraesophageal abscess: an uncommon cause of dysphagia in epidermolysis bullosa].
Gastroenterol Hepatol
PUBLISHED: 03-01-2011
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Epidermolysis bullosa encompasses a group of disorders characterized by the development of blisters on the skin and mucous membranes after minimal trauma. Gastrointestinal involvement is almost always present in the recessive dystrophic form, with the esophagus being one of the most frequent sites of extracutaneous manifestations. The most common symptom is dysphagia, which is usually secondary to esophageal blisters that evolve to scar tissue and stenosis.
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Prospects for malaria elimination in non-Amazonian regions of Latin America.
Acta Trop.
PUBLISHED: 02-22-2011
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Latin America contributes 1-1.2 million clinical malaria cases to the global malaria burden of about 300 million per year. In 21 malaria endemic countries, the population at risk in this region represents less than 10% of the total population exposed worldwide. Factors such as rapid deforestation, inadequate agricultural practices, climate change, political instability, and both increasing parasite drug resistance and vector resistance to insecticides contribute to malaria transmission. Recently, several malaria endemic countries have experienced a significant reduction in numbers of malaria cases. This is most likely due to actions taken by National Malaria Control Programs (NMCP) with the support from international funding agencies. We describe here the research strategies and activities to be undertaken by the Centro Latino Americano de Investigación en Malaria (CLAIM), a new research center established for the non-Amazonian region of Latin America by the National Institute of Allergy and Infectious Diseases (NIAID). Throughout a network of countries in the region, initially including Colombia, Guatemala, Panama, and Peru, CLAIM will address major gaps in our understanding of changing malaria epidemiology, vector biology and control, and clinical malaria mainly due to Plasmodium vivax. In close partnership with NMCPs, CLAIM seeks to conduct research on how and why malaria is decreasing in many countries of the region as a basis for developing and implementing new strategies that will accelerate malaria elimination.
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Spatio-temporal analysis of mortality among children under the age of five in Manhiça (Mozambique) during the period 1997-2005.
Int J Health Geogr
PUBLISHED: 02-18-2011
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Reducing childhood mortality is the fourth goal of the Millennium Development Goals agreed at the United Nations Millennium Summit in September 2000. However, childhood mortality in developing countries remains high. Providing an accurate picture of space and time-trend variations in child mortality in a region might generate further ideas for health planning actions to achieve such a reduction. The purpose of this study was to examine the spatio-temporal variation for child mortality rates in Manhiça, a district within the Maputo province of southern rural Mozambique during the period 1997-2005 using a proper generalized linear mixed model.
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Evaluating the effectiveness of IPTi on malaria using routine health information from sentinel health centres in southern Tanzania.
Malar. J.
PUBLISHED: 02-14-2011
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Intermittent preventive treatment of malaria in infants (IPTi) consists of the administration of a treatment dose of sulphadoxine-pyrimethamine (SP) at the time of routine vaccinations. The use of routine Health Management and Information Services (HMIS) data to investigate the effect of IPTi on malaria, anaemia, and all-cause attendance in children aged 2-11 months presenting to 11 health centres in southern Tanzania is described.
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Parity and placental infection affect antibody responses against Plasmodium falciparum during pregnancy.
Infect. Immun.
PUBLISHED: 02-07-2011
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Women are at higher risk of Plasmodium falciparum infection when pregnant. The decreasing risk of malaria with subsequent pregnancies is attributed to parity-dependent acquisition of antibodies against placental parasites expressing variant surface antigens, VAR2CSA, that mediate placental sequestration through adhesion to chondroitin sulfate A (CSA). However, modulation of immunity during pregnancy may also contribute to increase the risk of malaria. We compared antibody responses among 30 Mozambican primigravidae and 60 multigravidae at delivery, 40 men, and 40 children. IgG levels were measured against the surface antigens of erythrocytes infected with P. falciparum isolated from 12 pregnant women (4 placental and 8 peripheral blood isolates) and 26 nonpregnant hosts. We also measured IgG levels against merozoite recombinant antigens and total IgG. Placental P. falciparum infection was associated with increased levels of total IgG as well as IgG levels against merozoite antigens and parasite isolates from pregnant and nonpregnant hosts. We therefore stratified comparisons of antibody levels by placental infection. Compared to multigravidae, uninfected primigravidae had lower total IgG as well as lower levels of IgGs against peripheral blood isolates from both pregnant and nonpregnant hosts. These differences were not explained by use of bed nets, season at delivery, neighborhood of residence, or age. Compared to men, infected primigravidae had higher levels of IgGs against isolates from pregnant women and CSA-binding lines but not against other isolates, supporting the concept of a pregnancy-specific development of immunity to these parasite variants. Results of this study show that parity and placental infection can modulate immune responses during pregnancy against malaria parasites.
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Some lessons for the future from the Global Malaria Eradication Programme (1955-1969).
PLoS Med.
PUBLISHED: 01-25-2011
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Encouraged by the early success of using dichloro-diphenyl-trichloroethane (DDT) against malaria, the World Health Organization (WHO) embarked on the Global Malaria Eradication Program (GMEP) in 1955. Fourteen years later, the campaign was discontinued when it was recognised that eradication was not achievable with the available means in many areas, although the long-term goal remained unchanged. During the GMEP, malaria was permanently eliminated from many regions. In other areas, however, substantial gains were lost in resurgences, sometimes of epidemic proportions. During the 1970s and 1980s, because of economic and financial crises, international support for malaria control declined rapidly, but in the past decade, following increasing demands from endemic countries and promising results from scaling up of control activities, interest in malaria elimination and the long-term goal of eradication has received international political and financial support. In 2007, there was a renewed call for malaria eradication and a consultative process to define a research and development agenda for malaria eradication (malERA) was established. Lessons learned from the GMEP (1955-1969) highlight the fact that no single strategy can be applicable everywhere and that a long-term commitment with a flexible strategy that includes community involvement, integration with health systems, and the development of agile surveillance systems is needed.
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A research agenda to underpin malaria eradication.
PLoS Med.
PUBLISHED: 01-25-2011
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The interruption of malaria transmission worldwide is one of the greatest challenges for international health and development communities. The current expert view suggests that, by aggressively scaling up control with currently available tools and strategies, much greater gains could be achieved against malaria, including elimination from a number of countries and regions; however, even with maximal effort we will fall short of global eradication. The Malaria Eradication Research Agenda (malERA) complements the current research agenda--primarily directed towards reducing morbidity and mortality--with one that aims to identify key knowledge gaps and define the strategies and tools that will result in reducing the basic reproduction rate to less than 1, with the ultimate aim of eradication of the parasite from the human population. Sustained commitment from local communities, civil society, policy leaders, and the scientific community, together with a massive effort to build a strong base of researchers from the endemic areas will be critical factors in the success of this new agenda.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.