Deglutition manifestations in patients with oropharyngeal cancer subjected to conservative therapy: systematic review / Manifestações da deglutição em pacientes com câncer de orofaringe submetidos à terapia conservadora: revisão sistemática

ABSTRACT Objectives: To characterize scientific production and identify deglutition changes in individuals with oropharyngeal cancer subjected to conservative therapy. Methods: The search was applied to five electronic database [Scientific Electronic Library Online (Scielo), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), US National Library of Medicine National Institutes of Health (PubMed), Web of Science, and Scopus], besides the search of grey literature in the databases (OpenThesis e OpenGrey), avoiding selection and publication bias. Prospective longitudinal studies concerning the theme: deglutition disorders in individuals with oropharyngeal cancer subjected to conservative therapy were considered eligible. The risk of bias and the evaluation of individual methodological quality of the selected studies were measured by "The Joanna Briggs Institute Critical Appraisal tools for use in JBI Systematic Reviews" for prospective and longitudinal studies. Results: The search resulted in 899 records and after analysis four of them fulfilled the eligibility criteria. Among the studies included, all individuals presented some type of deglutition changes, the most common were: reduced of strength and retraction of the base of the tongue, delayed deglutition trigger, reduced laryngeal elevation, presence of residues on tongue and palate, in the pharyngeal area, valleculae, and posterior pharyngeal wall, as well as in the vestibules and in pyriform sinuses. Conclusion: The evidence from this systematic review suggests that conservative therapies cause deglutition changes or amplify the pre-existing ones, regardless of the type and magnitude of radiation, as well as tumor staging. However, there is little standardization in the research methodologies, making a meta-analysis study difficult to conduct.

RESUMEN Objetivos: Caracterizar la producción científica e identificar las alteraciones de deglución en personas con cáncer de orofaringe sometidas a tratamiento conservador. Métodos: Se realizó una búsqueda en cinco bases de datos electrónicas [Scientific Electronic Library Online (Scielo), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), US National Library of Medicine National Institutes of Health (PubMed), Web of Science y Scopus], además de la literatura gris en las bases de datos OpenThesis y OpenGrey, evitando sesgo de selección y publicación. Se consideraron elegibles los estudios longitudinales prospectivos sobre el tema: trastornos de deglución en pacientes con cáncer de orofaringe sometidos a tratamiento conservador. El riesgo de sesgo y la calidad metodológica individual de los estudios seleccionados se evaluaron mediante la herramienta de evaluación crítica del Instituto Joanna Briggs (JBI) para uso de sus revisiones sistemáticas, estudios prospectivos y longitudinales. Resultados: La búsqueda encontró 899 registros y, tras análisis, cuatro de ellos cumplieron los criterios de elegibilidad. Entre los estudios incluidos, todos los pacientes presentaron algún tipo de trastorno de la deglución. Los más frecuentes fueron: fuerza y retracción reducidas de la base de la lengua, retraso en el disparo de la deglución, elevación laríngea reducida, presencia de residuo en lengua y paladar, en región faríngea, valléculas y pared posterior de la faringe, así como en el interior de los vestíbulos y en los senos piriformes. Conclusión: Esta revisión sistemática sugiere que los tratamientos conservadores producen alteraciones de deglución o intensifican aquellas que ya existen, independientemente del tipo y de la intensidad de radiación, así como de la estadificación del tumor. Hay, sin embargo, poca estandarización en las metodologías de investigación, lo que hace difícil un estudio de metanálisis.

RESUMO Objetivos: Caracterizar a produção científica e identificar as alterações da deglutição em indivíduos com câncer de orofaringe submetidos à terapia conservadora. Métodos: Realizou-se uma busca em cinco base de dados eletrônicas [Scientific Electronic Library Online (Scielo), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), US National Library of Medicine National Institutes of Health (PubMed), Web of Science e Scopus], além da busca da literatura cinzenta nas bases de dados (OpenThesis e OpenGrey), evitando viés de seleção e publicação. Foram considerados elegíveis estudos longitudinais prospectivos sobre o tema: alterações de deglutição em indivíduos com câncer de orofaringe submetidos à terapia conservadora. O risco de viés e a qualidade metodológica individual dos estudos selecionados foram avaliados pela ferramenta de avaliação crítica do Joanna Briggs Institute (JBI) para uso de suas revisões sistemáticas, estudos prospectivos e longitudinais. Resultados: A busca resultou em 899 registros e, após análise, quatro deles atenderam aos critérios de elegibilidade. Entre os estudos incluídos, todos os indivíduos apresentaram algum tipo de alteração de deglutição; os mais frequentes foram: força e retração da base da língua reduzidas, atraso no disparo da deglutição, elevação laríngea reduzida, presença de resíduo em língua e palato, em região faríngea, valéculas e parede posterior da faringe, bem como no interior dos vestíbulos e em seios piriformes. Conclusão: Esta revisão sistemática sugere que as terapias conservadoras produzem distúrbios de deglutição ou intensificam os já existentes, independentemente do tipo e da intensidade de radiação, bem como do estadiamento do tumor. Há, no entanto, pouca padronização nas metodologias das pesquisas, dificultando um estudo de metanálise.

Genome-wide diversity and differentiation in New World populations of the human malaria parasite Plasmodium vivax.

BACKGROUND: The Americas were the last continent colonized by humans carrying malaria parasites. Plasmodium falciparum from the New World shows very little genetic diversity and greater linkage disequilibrium, compared with its African counterparts, and is clearly subdivided into local, highly divergent populations. However, limited available data have revealed extensive genetic diversity in American populations of another major human malaria parasite, P. vivax. METHODS: We used an improved sample preparation strategy and next-generation sequencing to characterize 9 high-quality P. vivax genome sequences from northwestern Brazil. These new data were compared with publicly available sequences from recently sampled clinical P. vivax isolates from Brazil (BRA, total n = 11 sequences), Peru (PER, n = 23), Colombia (COL, n = 31), and Mexico (MEX, n = 19). PRINCIPAL FINDINGS/CONCLUSIONS: We found that New World populations of P. vivax are as diverse (nucleotide diversity π between 5.2 × 10-4 and 6.2 × 10-4) as P. vivax populations from Southeast Asia, where malaria transmission is substantially more intense. They display several non-synonymous nucleotide substitutions (some of them previously undescribed) in genes known or suspected to be involved in antimalarial drug resistance, such as dhfr, dhps, mdr1, mrp1, and mrp-2, but not in the chloroquine resistance transporter ortholog (crt-o) gene. Moreover, P. vivax in the Americas is much less geographically substructured than local P. falciparum populations, with relatively little between-population genome-wide differentiation (pairwise FST values ranging between 0.025 and 0.092). Finally, P. vivax populations show a rapid decline in linkage disequilibrium with increasing distance between pairs of polymorphic sites, consistent with very frequent outcrossing. We hypothesize that the high diversity of present-day P. vivax lineages in the Americas originated from successive migratory waves and subsequent admixture between parasite lineages from geographically diverse sites. Further genome-wide analyses are required to test the demographic scenario suggested by our data.

Naturally Acquired Binding-Inhibitory Antibodies to Plasmodium vivax Duffy Binding Protein and Clinical Immunity to Malaria in Rural Amazonians.

BACKGROUND: Antibodies to the cysteine-rich domain II of Plasmodium vivax Duffy binding protein (PvDBP) can inhibit binding of this parasite ligand to its receptor on red blood cells, the Duffy antigen/receptor for chemokines. These binding-inhibitory antibodies (BIAbs) also inhibit P. vivax invasion of reticulocytes in vitro. METHODS: To investigate whether naturally acquired anti-PvDBP antibodies are associated with reduced risk of clinical malaria in a population exposed to low levels of P. vivax transmission, we measured total levels of immunoglobulin G antibodies to 5 PvDBP variants and used a functional in vitro assay to quantify their binding-inhibitory activity in a cohort of 466 rural Amazonians followed up for up to 37 months. RESULTS: No association between total immunoglobulin G antibody responses to any PvDBP variant and risk of symptomatic, laboratory-confirmed vivax malaria was observed in this cohort. However, a Cox proportional hazards model, adjusted for age, sex, and genotype for the Duffy antigen/receptor for chemokines, showed a >40% decrease in the prospective risk of clinical vivax malaria in subjects with the strongest BIAb responses (upper and middle terciles). High BIAb responses were mostly PvDBP variant transcending and stable over time. CONCLUSIONS: Strong naturally acquired BIAb responses are associated with a reduced risk of clinical P. vivax malaria in rural Amazonians.

Genetic diversity of Plasmodium vivax over time and space: a community-based study in rural Amazonia.

To examine how community-level genetic diversity of the malaria parasite Plasmodium vivax varies across time and space, we investigated the dynamics of parasite polymorphisms during the early phases of occupation of a frontier settlement in the Amazon Basin of Brazil. Microsatellite characterization of 84 isolates of P. vivax sampled over 3 years revealed a moderate-to-high genetic diversity (mean expected heterozygosity, 0.699), with a large proportion (78.5%) of multiple-clone infections (MCI), but also a strong multilocus linkage disequilibrium (LD) consistent with rare outcrossing. Little temporal and no spatial clustering was observed in the distribution of parasite haplotypes. A single microsatellite haplotype was shared by 3 parasites collected during an outbreak; all other 81 haplotypes were recovered only once. The lowest parasite diversity, with the smallest proportion of MCI and the strongest LD, was observed at the time of the outbreak, providing a clear example of epidemic population structure in a human pathogen. Population genetic parameters returned to pre-outbreak values during last 2 years of study, despite the concomitant decline in malaria incidence. We suggest that parasite genotyping can be useful for tracking the spread of new parasite strains associated with outbreaks in areas approaching malaria elimination.

Epidemiology of disappearing Plasmodium vivax malaria: a case study in rural Amazonia.

BACKGROUND: New frontier settlements across the Amazon Basin pose a major challenge for malaria elimination in Brazil. Here we describe the epidemiology of malaria during the early phases of occupation of farming settlements in Remansinho area, Brazilian Amazonia. We examine the relative contribution of low-density and asymptomatic parasitemias to the overall Plasmodium vivax burden over a period of declining transmission and discuss potential hurdles for malaria elimination in Remansinho and similar settings. METHODS: Eight community-wide cross-sectional surveys, involving 584 subjects, were carried out in Remansinho over 3 years and complemented by active and passive surveillance of febrile illnesses between the surveys. We used quantitative PCR to detect low-density asexual parasitemias and gametocytemias missed by conventional microscopy. Mixed-effects multiple logistic regression models were used to characterize independent risk factors for P. vivax infection and disease. PRINCIPAL FINDINGS/CONCLUSIONS: P. vivax prevalence decreased from 23.8% (March-April 2010) to 3.0% (April-May 2013), with no P. falciparum infections diagnosed after March-April 2011. Although migrants from malaria-free areas were at increased risk of malaria, their odds of having P. vivax infection and disease decreased by 2-3% with each year of residence in Amazonia. Several findings indicate that low-density and asymptomatic P. vivax parasitemias may complicate residual malaria elimination in Remansinho: (a) the proportion of subpatent infections (i.e. missed by microscopy) increased from 43.8% to 73.1% as P. vivax transmission declined; (b) most (56.6%) P. vivax infections were asymptomatic and 32.8% of them were both subpatent and asymptomatic; (c) asymptomatic parasite carriers accounted for 54.4% of the total P. vivax biomass in the host population; (d) over 90% subpatent and asymptomatic P. vivax had PCR-detectable gametocytemias; and (e) few (17.0%) asymptomatic and subpatent P. vivax infections that were left untreated progressed to clinical disease over 6 weeks of follow-up and became detectable by routine malaria surveillance.

Versão Portuguesa da Escala Breve de Redes Sociais de Lubben (LSNS-6) / Portuguese version of the abbreviated Lubben Social Network Scale (LSNS-6)

A avaliação das redes sociais na investigação e prática gerontológica requer o uso de instrumentos válidos e eficazes que sejam simples, concisos e de fácil aplicação na população idosa. A Escala de Redes Sociais de Lubben (LSNS) é um dos instrumentos mais utilizados para avaliar a integração social e o risco de isolamento social em idosos residentes na comunidade. Este artigo debruça-se sobre a tradução e validação da versão abreviada da escala (LSNS-6) para o Português Europeu e expõe as suas principais características psicométricas.(AU)

The assessment of social networks in gerontological and research practice requires valid, concise and reliable short scales that can be easily used with older adults. The Lubben Social Network Scale (LSNS) is one of the most widely used instruments to assess social integration and to screen for social isolation among community-dwelling populations. This study presents the translation and validation process of the SNLS abbreviated version (LSNS-6) to European Portuguese. Main psychometric properties are discussed.(AU)

Versão Portuguesa da Escala Breve de Redes Sociais de Lubben (LSNS-6) / Portuguese version of the abbreviated Lubben Social Network Scale (LSNS-6)

A avaliação das redes sociais na investigação e prática gerontológica requer o uso de instrumentos válidos e eficazes que sejam simples, concisos e de fácil aplicação na população idosa. A Escala de Redes Sociais de Lubben (LSNS) é um dos instrumentos mais utilizados para avaliar a integração social e o risco de isolamento social em idosos residentes na comunidade. Este artigo debruça-se sobre a tradução e validação da versão abreviada da escala (LSNS-6) para o Português Europeu e expõe as suas principais características psicométricas.

The assessment of social networks in gerontological and research practice requires valid, concise and reliable short scales that can be easily used with older adults. The Lubben Social Network Scale (LSNS) is one of the most widely used instruments to assess social integration and to screen for social isolation among community-dwelling populations. This study presents the translation and validation process of the SNLS abbreviated version (LSNS-6) to European Portuguese. Main psychometric properties are discussed.

Challenges in estimating insecticide selection pressures from mosquito field data.

Insecticide resistance has the potential to compromise the enormous effort put into the control of dengue and malaria vector populations. It is therefore important to quantify the amount of selection acting on resistance alleles, their contributions to fitness in heterozygotes (dominance) and their initial frequencies, as a means to predict the rate of spread of resistance in natural populations. We investigate practical problems of obtaining such estimates, with particular emphasis on Mexican populations of the dengue vector Aedes aegypti. Selection and dominance coefficients can be estimated by fitting genetic models to field data using maximum likelihood (ML) methodology. This methodology, although widely used, makes many assumptions so we investigated how well such models perform when data are sparse or when spatial and temporal heterogeneity occur. As expected, ML methodologies reliably estimated selection and dominance coefficients under idealised conditions but it was difficult to recover the true values when datasets were sparse during the time that resistance alleles increased in frequency, or when spatial and temporal heterogeneity occurred. We analysed published data on pyrethroid resistance in Mexico that consists of the frequency of a Ile1,016 mutation. The estimates for selection coefficient and initial allele frequency on the field dataset were in the expected range, dominance coefficient points to incomplete dominance as observed in the laboratory, although these estimates are accompanied by strong caveats about possible impact of spatial and temporal heterogeneity in selection.