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1.
bioRxiv ; 2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39229023

RESUMO

Targeted amplicon sequencing is a powerful and efficient tool to interrogate the P. falciparum genome and generate actionable data from infections to complement traditional malaria epidemiology. For maximum impact, genomic tools should be multi-purpose, robust, sensitive and reproducible. We developed, characterized, and implemented MAD4HatTeR, an amplicon sequencing panel based on Multiplex Amplicons for Drug, Diagnostic, Diversity, and Differentiation Haplotypes using Targeted Resequencing, along with a bioinformatic pipeline for data analysis. MAD4HatTeR targets 165 highly diverse loci, focusing on multiallelic microhaplotypes; key markers for drug and diagnostic resistance, including duplications and deletions; and csp and potential vaccine targets. In addition, it can detect non-falciparum Plasmodium species. We used laboratory control and field sample data to demonstrate the high sensitivity and robustness of the panel. The successful implementation of this method in five laboratories, including three in malaria-endemic African countries, showcases its feasibility in generating reproducible data across laboratories. Finally, we introduce an analytical approach to detect gene duplications and deletions from amplicon sequencing data. MAD4HatTeR is thus a powerful research tool and a robust resource for malaria public health surveillance and control.

2.
Antimicrob Agents Chemother ; 68(7): e0034624, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38771031

RESUMO

While the Plasmodium falciparum malaria parasite continues to cause severe disease globally, Mozambique is disproportionally represented in malaria case totals. Acquisition of copy number variations (CNVs) in the parasite genome contributes to antimalarial drug resistance through overexpression of drug targets. Of interest, piperaquine resistance is associated with plasmepsin 2 and 3 CNVs (pfpmp2 and pfpmp3, respectively), while CNVs in the multidrug efflux pump, multidrug resistance-1 (pfmdr1), increase resistance to amodiaquine and lumefantrine. These antimalarials are partner drugs in artemisinin combination therapies (ACTs) and therefore, CNV detection with accurate and efficient tools is necessary to track ACT resistance risk. Here, we evaluated ~300 clinically derived samples collected from three sites in Mozambique for resistance-associated CNVs. We developed a novel, medium-throughput, quadruplex droplet digital PCR (ddPCR) assay to simultaneously quantify the copy number of pfpmp3, pfpmp2, and pfmdr1 loci in these clinical samples. By using DNA from laboratory parasite lines, we show that this nanodroplet-based method is capable of detecting picogram levels of parasite DNA, which facilitates its application for low yield and human host-contaminated clinical surveillance samples. Following ddPCR and the application of quality control standards, we detected CNVs in 13 of 229 high-quality samples (prevalence of 5.7%). Overall, our study revealed a low number of resistance CNVs present in the parasite population across all three collection sites, including various combinations of pfmdr1, pfpmp2, and pfpmp3 CNVs. The potential for future ACT resistance across Mozambique emphasizes the need for continued molecular surveillance across the region.


Assuntos
Antimaláricos , Variações do Número de Cópias de DNA , Resistência a Medicamentos , Malária Falciparum , Plasmodium falciparum , Proteínas de Protozoários , Antimaláricos/farmacologia , Moçambique , Plasmodium falciparum/genética , Plasmodium falciparum/efeitos dos fármacos , Humanos , Resistência a Medicamentos/genética , Variações do Número de Cópias de DNA/genética , Malária Falciparum/parasitologia , Malária Falciparum/tratamento farmacológico , Proteínas de Protozoários/genética , Reação em Cadeia da Polimerase/métodos , Quinolinas/farmacologia , Amodiaquina/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Ácido Aspártico Endopeptidases/genética , Artemisininas/farmacologia , Lumefantrina/farmacologia , Piperazinas
3.
Nat Commun ; 15(1): 2402, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493162

RESUMO

Routine sampling of pregnant women at first antenatal care (ANC) visits could make Plasmodium falciparum genomic surveillance more cost-efficient and convenient in sub-Saharan Africa. We compare the genetic structure of parasite populations sampled from 289 first ANC users and 93 children from the community in Mozambique between 2015 and 2019. Samples are amplicon sequenced targeting 165 microhaplotypes and 15 drug resistance genes. Metrics of genetic diversity and relatedness, as well as the prevalence of drug resistance markers, are consistent between the two populations. In an area targeted for elimination, intra-host genetic diversity declines in both populations (p = 0.002-0.007), while for the ANC population, population genetic diversity is also lower (p = 0.0004), and genetic relatedness between infections is higher (p = 0.002) than control areas, indicating a recent reduction in the parasite population size. These results highlight the added value of genomic surveillance at ANC clinics to inform about changes in transmission beyond epidemiological data.


Assuntos
Malária Falciparum , Malária , Parasitos , Criança , Animais , Feminino , Gravidez , Humanos , Cuidado Pré-Natal/métodos , Moçambique/epidemiologia , Malária/epidemiologia , Malária/prevenção & controle , Plasmodium falciparum/genética , Genômica , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Malária Falciparum/parasitologia
4.
Res Sq ; 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38014035

RESUMO

Routine sampling of pregnant women at first antenatal care (ANC) visits could make Plasmodium falciparum genomic surveillance more cost-efficient and convenient in sub-Saharan Africa. We compared the genetic structure of parasite populations sampled from 289 first ANC attendees and 93 children from the community in Mozambique between 2015 and 2019. Samples were amplicon sequenced targeting 165 microhaplotypes and 15 drug resistance genes. Metrics of genetic diversity and relatedness, as well as the prevalence of drug resistance markers, were consistent between the two populations. In an area targeted for elimination, intra-host genetic diversity declined in both populations (p=0.002-0.007), while for the ANC population, population genetic diversity was also lower (p=0.0004), and genetic relatedness between infections were higher (p=0.002) than control areas, indicating a recent reduction in the parasite population size. These results highlight the added value of genomic surveillance at ANC clinics to inform about changes in transmission beyond epidemiological data.

5.
Commun Biol ; 6(1): 619, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37291425

RESUMO

Mozambique is one of the four African countries which account for over half of all malaria deaths worldwide, yet little is known about the parasite genetic structure in that country. We performed P. falciparum amplicon and whole genome sequencing on 2251 malaria-infected blood samples collected in 2015 and 2018 in seven provinces of Mozambique to genotype antimalarial resistance markers and interrogate parasite population structure using genome-wide microhaplotyes. Here we show that the only resistance-associated markers observed at frequencies above 5% were pfmdr1-184F (59%), pfdhfr-51I/59 R/108 N (99%) and pfdhps-437G/540E (89%). The frequency of pfdhfr/pfdhps quintuple mutants associated with sulfadoxine-pyrimethamine resistance increased from 80% in 2015 to 89% in 2018 (p < 0.001), with a lower expected heterozygosity and higher relatedness of microhaplotypes surrounding pfdhps mutants than wild-type parasites suggestive of recent selection. pfdhfr/pfdhps quintuple mutants also increased from 72% in the north to 95% in the south (2018; p < 0.001). This resistance gradient was accompanied by a concentration of mutations at pfdhps-436 (17%) in the north, a south-to-north increase in the genetic complexity of P. falciparum infections (p = 0.001) and a microhaplotype signature of regional differentiation. The parasite population structure identified here offers insights to guide antimalarial interventions and epidemiological surveys.


Assuntos
Antimaláricos , Malária Falciparum , Malária , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Moçambique , Plasmodium falciparum/genética , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária/tratamento farmacológico , Resistência a Medicamentos/genética , Sequenciamento Completo do Genoma , Estruturas Genéticas
6.
Malar J ; 22(1): 160, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208708

RESUMO

BACKGROUND: Malaria remains one of the most serious public health problems in sub-Saharan Africa and Mozambique is the world's fourth largest contributor, with 4.7% of disease cases and 3.6% of total deaths due to malaria. Its control relies on the fight against the vector and treatment of confirmed cases with anti-malarial drugs. Molecular surveillance is an important tool for monitoring the spread of anti-malarial drug resistance. METHODS: A cross-sectional study recruited 450 participants with malaria infection detected by Rapid Diagnostic Tests, from three different study sites (Niassa, Manica and Maputo) between April and August 2021. Correspondent blood samples were collected on filter paper (Whatman® FTA® cards), parasite DNA extracted and pfk13 gene sequenced using Sanger method. SIFT software (Sorting Intolerant From Tolerant) was used, predict whether an amino acid substitution affects protein function. RESULTS: No pfkelch13-mediated artemisinin resistance gene mutation was detected in this study settings. However, non-synonymous mutations were detected at prevalence of 10.2%, 6% and 5% in Niassa, Manica and Maputo, respectively. Most (56.3%) of the reported non-synonymous mutations were due to substitution at the first base of the codon, 25% at the second base and 18.8% at the third base. Additionally, 50% of non-synonymous mutations showed a SIFTscore bellow cut off value of 0.05, therefore, they were predicted to be deleterious. CONCLUSION: These results do not show an emergence of artemisinin resistance cases in Mozambique. However, the increased number of novel non-synonymous mutations highlights the relevance of increasing the number of studies focused on the molecular surveillance of artemisinin resistance markers, for its early detection.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Moçambique/epidemiologia , Estudos Transversais , Malária Falciparum/parasitologia , Artemisininas/uso terapêutico , Mutação , Resistência a Medicamentos/genética , Proteínas de Protozoários/metabolismo
7.
BMJ Open ; 12(7): e063456, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35820756

RESUMO

INTRODUCTION: Genomic data constitute a valuable adjunct to routine surveillance that can guide programmatic decisions to reduce the burden of infectious diseases. However, genomic capacities remain low in Africa. This study aims to operationalise a functional malaria molecular surveillance system in Mozambique for guiding malaria control and elimination. METHODS AND ANALYSES: This prospective surveillance study seeks to generate Plasmodium falciparum genetic data to (1) monitor molecular markers of drug resistance and deletions in rapid diagnostic test targets; (2) characterise transmission sources in low transmission settings and (3) quantify transmission levels and the effectiveness of antimalarial interventions. The study will take place across 19 districts in nine provinces (Maputo city, Maputo, Gaza, Inhambane, Niassa, Manica, Nampula, Zambézia and Sofala) which span a range of transmission strata, geographies and malaria intervention types. Dried blood spot samples and rapid diagnostic tests will be collected across the study districts in 2022 and 2023 through a combination of dense (all malaria clinical cases) and targeted (a selection of malaria clinical cases) sampling. Pregnant women attending their first antenatal care visit will also be included to assess their value for molecular surveillance. We will use a multiplex amplicon-based next-generation sequencing approach targeting informative single nucleotide polymorphisms, gene deletions and microhaplotypes. Genetic data will be incorporated into epidemiological and transmission models to identify the most informative relationship between genetic features, sources of malaria transmission and programmatic effectiveness of new malaria interventions. Strategic genomic information will be ultimately integrated into the national malaria information and surveillance system to improve the use of the genetic information for programmatic decision-making. ETHICS AND DISSEMINATION: The protocol was reviewed and approved by the institutional (CISM) and national ethics committees of Mozambique (Comité Nacional de Bioética para Saúde) and Spain (Hospital Clinic of Barcelona). Project results will be presented to all stakeholders and published in open-access journals. TRIAL REGISTRATION NUMBER: NCT05306067.


Assuntos
Antimaláricos , Malária , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Resistência a Medicamentos/genética , Feminino , Deleção de Genes , Humanos , Malária/epidemiologia , Moçambique/epidemiologia , Estudos Multicêntricos como Assunto , Plasmodium falciparum/genética , Gravidez , Estudos Prospectivos
8.
BMC Med Ethics ; 22(1): 139, 2021 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-34656108

RESUMO

BACKGROUND: Organ transplantation represents the most effective and acceptable therapy for end-stage organ failure. However, its frequent practice often leads to a shortage of organs worldwide. To solve this dilemma, some countries, such as Portugal, have switched from an opt-in to an opt-out system, which has raised concerns about respect for individual autonomy. We aimed to evaluate whether young university students are aware of this opt-out system so that they can make informed, autonomous and conscious decisions, as well as to identify the factors that determine a positive attitude toward post-mortem organ donation. METHODS: An observational, cross-sectional study was developed and a questionnaire was administered to first-year students from six faculties of the University of Porto. RESULTS: Of the 841 participants, 60% were unaware that Portugal had adopted an opt-out system. Among the informed individuals, their main sources of information included social media, internet, and family. Furthermore, only 48% of all participants agreed with the current opt-out system. Female sex (p = 0.049; OR 1.393), knowledge of the law (p < 0.001; OR 4.749) and family being the primary source of information (p < 0.001; OR 2.855) were independent factors associated with a positive attitude toward post-mortem organ donation law. CONCLUSIONS: There is a significant lack of knowledge among young university students regarding the presumed post-mortem organ donation law and how it works. Female sex, having family as a primary source of information and being aware of the presumed post-mortem organ donation law are the strongest independent factors that determine a positive attitude toward the opt-out system.


Assuntos
Obtenção de Tecidos e Órgãos , Universidades , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Consentimento Presumido , Estudantes , Inquéritos e Questionários , Doadores de Tecidos
9.
Materials (Basel) ; 12(7)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939723

RESUMO

In this work, the meso-tetra[4-(2-(3-n-pentadecylphenoxy)ethoxy]phenylporphyrin (H2P), obtained from the cashew nut shell liquid (CNSL), and its zinc (ZnP) and copper (CuP) metallic complexes, were applied as emitting layers in organic light emitting diodes (OLEDs). These compounds were characterized via optical and electrochemical analysis and the electroluminescent properties of the device have been studied. We performed a cyclic voltammetry analysis to determine the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) energy levels for the porphyrins, in order to select the proper materials to assemble the device. H2P and ZnP presented fluorescence emission band in the red region, from 601 nm to 718 nm. Moreover, we verified that the introduction of bulky substituents hinders the π⁻π stacking, favoring the emission in the film. In addition, the strongest emitter, ZnP, presented a threshold voltage of 4 V and the maximum irradiance of 10 µW cm-2 with a current density (J) of 15 mA cm-2 at 10 V. The CuP complex showed to be a favorable material for the design of OLEDs in the infrared. These results suggest that the porphyrins derived from a renewable source, such as CNSL, is a promising material to be used in organic optoelectronic devices such as OLEDs.

10.
Rev. enferm. UFPE on line ; 12(4): 1091-1096, abr. 2018.
Artigo em Português | BDENF - enfermagem (Brasil) | ID: biblio-970725

RESUMO

Objetivo: discutir acerca dos métodos não farmacológicos para alívio da dor no parto domiciliar. Método: estudo qualitativo tipo análise reflexiva originado na iniciação científica do curso de graduação em enfermagem, mediante as seguintes etapas: busca nas bases de dados, leitura do material selecionado, movimento da práxis analítica da temática e formulação do material escrito. Resultados: há uma gama de métodos utilizados no ambiente domiciliar para o alívio da dor, como o banho de aspersão/imersão, bola suíça, método "cavalinho", "banquinho U", musicoterapia, aromaterapia, massagens, acupressão e deambulação. Desse modo, essas práticas contribuem para inibição de estímulos dolorosos e promovendo o conforto para o processo parturitivo. Conclusão: o parto domiciliar surge com o propósito de trazer de volta a autonomia da mulher sobre seu corpo, protagonismo, resguardando seu direito a um parto respeitoso e essas práticas não farmacológicas permitem a mulher vivenciar o parto de forma humanizada e respeitosa.(AU)


Assuntos
Humanos , Feminino , Gravidez , Trabalho de Parto , Parto Humanizado , Dor do Parto , Parto Domiciliar , Parto Normal , Enfermeiros Obstétricos , Enfermagem Obstétrica , Pesquisa Qualitativa
11.
Rev. enferm. UFPE on line ; 11(12): 5074-5078, dez.2017.
Artigo em Português | BDENF - enfermagem (Brasil) | ID: biblio-1031982

RESUMO

Objetivo: discutir, a partir da análise reflexiva, acerca da assistência ofertada a mulher em situação deabortamento. Método: estudo qualitativo, do tipo análise reflexiva, originado na iniciação científica do cursode graduação em enfermagem, mediante das seguintes etapas: busca nas bases de dados, leitura do materialselecionado, movimento da práxis analítica da temática, e formulação do material escrito. Resultados: asmulheres que realizam o aborto são submetidas ao desrespeito frente a sua escolha, culpabilizadas pelafamília, profissionais de saúde e sociedade, discriminadas e marginalizadas, e carecem de apoio de ordemfísica, emocional e psicológica. Conclusão: o cuidado deve ser focalizado na mulher, de forma integral, earticular para a qualidade e humanização da assistência. Devendo, o respeito as suas escolhas, sem ojulgamento em que muitos profissionais executam, e desrespeitando as mulheres em situação deabortamento.


Assuntos
Feminino , Humanos , Gravidez , Aborto Criminoso , Aborto Espontâneo , Aborto Induzido , Enfermagem Obstétrica , Humanização da Assistência , Relações Enfermeiro-Paciente , Saúde da Mulher , Pesquisa Qualitativa
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