RESUMO
BACKGROUND: Studies on haemosporidian diversity, including origin of human malaria parasites, malaria's zoonotic dynamic, and regional biodiversity patterns, have used target gene approaches. However, current methods have a trade-off between scalability and data quality. Here, a long-read Next-Generation Sequencing protocol using PacBio HiFi is presented. The data processing is supported by a pipeline that uses machine-learning for analysing the reads. METHODS: A set of primers was designed to target approximately 6 kb, almost the entire length of the haemosporidian mitochondrial genome. Amplicons from different samples were multiplexed in an SMRTbell® library preparation. A pipeline (HmtG-PacBio Pipeline) to process the reads is also provided; it integrates multiple sequence alignments, a machine-learning algorithm that uses modified variational autoencoders, and a clustering method to identify the mitochondrial haplotypes/species in a sample. Although 192 specimens could be studied simultaneously, a pilot experiment with 15 specimens is presented, including in silico experiments where multiple data combinations were tested. RESULTS: The primers amplified various haemosporidian parasite genomes and yielded high-quality mt genome sequences. This new protocol allowed the detection and characterization of mixed infections and co-infections in the samples. The machine-learning approach converged into reproducible haplotypes with a low error rate, averaging 0.2% per read (minimum of 0.03% and maximum of 0.46%). The minimum recommended coverage per haplotype is 30X based on the detected error rates. The pipeline facilitates inspecting the data, including a local blast against a file of provided mitochondrial sequences that the researcher can customize. CONCLUSIONS: This is not a diagnostic approach but a high-throughput method to study haemosporidian sequence assemblages and perform genotyping by targeting the mitochondrial genome. Accordingly, the methodology allowed for examining specimens with multiple infections and co-infections of different haemosporidian parasites. The pipeline enables data quality assessment and comparison of the haplotypes obtained to those from previous studies. Although a single locus approach, whole mitochondrial data provide high-quality information to characterize species pools of haemosporidian parasites.
Assuntos
Genoma Mitocondrial , Haemosporida , Sequenciamento de Nucleotídeos em Larga Escala , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Haemosporida/genética , Haemosporida/classificação , Biodiversidade , Aprendizado de MáquinaRESUMO
BACKGROUND: Pfhrp2 and pfhrp3 deletions are threatening Plasmodium falciparum malaria diagnosis by rapid diagnostic tests (RDT) due to false negatives. This study assesses the changes in the frequencies of pfhrp2 and pfhrp3 deletions (pfhrp2Del and pfhrp3Del, respectively) and the genes in their flaking regions, before and after RDT introduction in Equatorial Guinea. METHODS: A total of 566 P. falciparum samples were genotyped to assess the presence of pfhrp2 and pfhrp3 deletions and their flanking genes. The specimens were collected 18 years apart from two provinces of Equatorial Guinea, North Bioko (Insular Region) and Litoral Province (Continental Region). Orthologs of pfhrp2 and pfhrp3 genes from other closely related species were used to compare sequencing data to assess pfhrp2 and pfhrp3 evolution. Additionally, population structure was studied using seven neutral microsatellites. RESULTS: This study found that pfhrp2Del and pfhrp3Del were present before the introduction of RDT; however, they increased in frequency after their use, reaching more than 15%. Haplotype networks suggested that pfhrp2Del and pfhrp3Del emerged multiple times. Exon 2 of pfhrp2 and pfhrp3 genes had high variability, but there were no significant changes in amino acid sequences. CONCLUSIONS: Baseline sampling before deploying interventions provides a valuable context to interpret changes in genetic markers linked to their efficacy, such as the dynamic of deletions affecting RDT efficacy.
Assuntos
Antígenos de Protozoários , Plasmodium falciparum , Proteínas de Protozoários , Guiné Equatorial , Proteínas de Protozoários/genética , Antígenos de Protozoários/genética , Plasmodium falciparum/genética , Evolução Molecular , Malária Falciparum , Testes Diagnósticos de Rotina , Humanos , Deleção de Sequência , Deleção de GenesRESUMO
Overkill of large mammals is recognized as a key driver of Pleistocene megafaunal extinctions in the Americas and Australia. While this phenomenon primarily affected mega-mammals, its impact on large Quaternary reptiles has been debated. Freshwater turtles, due to the scarcity of giant forms in the Quaternary record, have been largely neglected in such discussions. Here we present a new giant podocnemidid turtle, Peltocephalus maturin sp. nov., from the Late Pleistocene Rio Madeira Formation in the Brazilian Amazon, that challenges this assumption. Morphological and phylogenetic analyses of the holotype, a massive partial lower jaw, reveal close affinities to extant Amazonian species and suggest an omnivorous diet. Body size regressions indicate Pe. maturin possibly reached about 180 cm in carapace length and is among the largest freshwater turtles ever found. This finding presents the latest known occurrence of giant freshwater turtles, hinting at coexistence with early human inhabitants in the Amazon.
Assuntos
Tartarugas , Animais , Humanos , Filogenia , Brasil , Répteis , Água Doce , MamíferosRESUMO
BACKGROUND: Deoxyguanosine kinase (DGUOK) deficiency is a rare mitochondrial disorder characterized by early onset liver failure and varying degrees of neurologic dysfunction. Patients typically present during infancy with progressive hepatic dysfunction leading to liver failure, which can precede neurologic deterioration. Outcomes posttransplantation are historically worse than average and the role of liver transplantation remains controversial. These factors, in combination with the increasing number of patients being diagnosed via molecular genetic testing, may impede waitlist access. METHODS: We report our single-center experience with three patients with DGUOK deficiency, all of whom were considered for transplant. We review the current literature regarding management and discuss the role of liver transplantation in DGUOK deficiency-associated liver failure. RESULTS: Two patients presented with hypoglycemia, conjugated hyperbilirubinemia, and lactic acidosis within the first week of life, were diagnosed with DGUOK deficiency prior to 2 months of age and had severe neurologic involvement. The third patient presented in later infancy was diagnosed with DGUOK deficiency at 18 months of age and had minimal neurologic involvement. All three patients were considered for transplant, though only two patients were listed. All three died from complications of end-stage liver failure prior to liver transplantation between the ages of 5-20 months. CONCLUSION: Selection for liver transplantation in DGUOK deficiency is complex, requiring a multidisciplinary team approach. Recent data suggest that liver transplantation can be successful in select patients with absent or mild neurologic manifestations. National databases reporting long-term outcomes posttransplantation are needed.
Assuntos
Doença Hepática Terminal , Transplante de Fígado , Doenças Mitocondriais , Humanos , Lactente , DNA Mitocondrial/genética , Doença Hepática Terminal/cirurgiaRESUMO
BACKGROUND AND OBJECTIVE: A significant proportion of women of childbearing age have psoriasis. The aim of this study was to examine family planning concerns in this population. MATERIAL AND METHODS: Observational, descriptive, cross-sectional, multicenter study conducted between March 2020 and October 2021. We collected sociodemographic data and analyzed responses to a family planning questionnaire administered to women aged 18 to 45 years with plaque psoriasis who were candidates for systemic treatment. RESULTS: We studied 153 patients (mean [SD] age, 35.4 [8.0] years; mean disease duration, 16.7 years) being treated at 11 Spanish hospitals. Overall, 38.4% of women were considered to have moderate to severe psoriasis by their physicians; perceived severity ratings were significantly higher among women. Psoriasis affected the women's desire to become pregnant or led to their delaying pregnancy in 1 in 3 respondents. They were concerned that their condition might worsen if they had to discontinue or switch treatment or that the treatment might harm the baby. Approximately half of the women had not received family planning counseling from their physicians, and this was more likely to be the case among never-pregnant women. Women on biologic therapy (58.7%) had better psoriasis control and a better quality of life than women on other treatments. Their sexual health was also less affected. CONCLUSIONS: Women with psoriasis have numerous family planning concerns, which in some cases can lead them to delay pregnancy or affect their desire to become pregnant. Dermatologists need to receive better training regarding family planning in women with psoriasis so that they can provide their patients with more and better information.
Assuntos
Serviços de Planejamento Familiar , Psoríase , Humanos , Feminino , Gravidez , Adulto , Estudos Transversais , Qualidade de Vida , Inquéritos e Questionários , Psoríase/tratamento farmacológicoRESUMO
BACKGROUND AND OBJECTIVE: A significant proportion of women of childbearing age have psoriasis. The aim of this study was to examine family planning concerns in this population. MATERIAL AND METHODS: Observational, descriptive, cross-sectional, multicenter study conducted between March 2020 and October 2021. We collected sociodemographic data and analyzed responses to a family planning questionnaire administered to women aged 18 to 45 years with plaque psoriasis who were candidates for systemic treatment. RESULTS: We studied 153 patients (mean [SD] age, 35.4 [8.0] years; mean disease duration, 16.7 years) being treated at 11 Spanish hospitals. Overall, 38.4% of women were considered to have moderate to severe psoriasis by their physicians; perceived severity ratings were significantly higher among women. Psoriasis affected the women's desire to become pregnant or led to their delaying pregnancy in 1 in 3 respondents. They were concerned that their condition might worsen if they had to discontinue or switch treatment or that the treatment might harm the baby. Approximately half of the women had not received family planning counseling from their physicians, and this was more likely to be the case among never-pregnant women. Women on biologic therapy (58.7%) had better psoriasis control and a better quality of life than women on other treatments. Their sexual health was also less affected. CONCLUSIONS: Women with psoriasis have numerous family planning concerns, which in some cases can lead them to delay pregnancy or affect their desire to become pregnant. Dermatologists need to receive better training regarding family planning in women with psoriasis so that they can provide their patients with more and better information.
Assuntos
Serviços de Planejamento Familiar , Psoríase , Humanos , Feminino , Gravidez , Adulto , Estudos Transversais , Qualidade de Vida , Inquéritos e Questionários , Psoríase/tratamento farmacológicoRESUMO
Morphological traits from blood stages have been the gold standard for determining haemosporidian parasite species. However, the status of some taxa and the value of such traits in parasites from reptiles remain contentious. The scarce sampling of these species worsens the situation, and several taxa lack molecular data. A survey was performed in the Magdalena Department in Colombia, where 16 species of reptiles were captured. A peculiar haemosporidian parasite was found in the Turnip-tailed gecko Thecadactylus rapicauda. This haemosporidian does not show malarial pigment in blood stages under light microscopy; thus, it fits the Garnia genus's characters belonging to the Garniidae. However, the phylogenetic analyses using a partial sequence of cytochrome b and the mitochondrial DNA placed it within the Plasmodium clade. Our findings suggest that many putative Garnia species belong to the genus Plasmodium, like the one reported here. This study either shows that visible malarial pigment in blood stages is not a diagnostic trait of the genus Plasmodium or malarial pigment might be present in an undetectable form under a light microscope. In any case, the current taxonomy of haemosporidian parasites in reptiles requires revision. This study highlights the importance of using molecular and morphological traits to address taxonomic questions at the species and genus levels in haemosporidian parasites from reptiles.
Assuntos
Brassica napus , Haemosporida , Lagartos , Parasitos , Plasmodium , Animais , Filogenia , Plasmodium/genética , Serpentes , Haemosporida/genéticaRESUMO
The distribution of avian haemosporidians of the genus Leucocytozoon in the Neotropics remains poorly understood. Recent studies confirmed their presence in the region using molecular techniques alone, but evidence for gametocytes and data on putative competent hosts for Leucocytozoon are still lacking outside highland areas. We combined morphological and molecular data to characterize a new Leucocytozoon species infecting a non-migratory red-legged seriema (Cariama cristata), the first report of a competent host for Leucocytozoon in Brazil. Leucocytozoon cariamae n. sp. is distinguished from the Leucocytozoon fringillinarum group by its microgametocytes that are not strongly appressed to the host cell nucleus. The bird studied was coinfected with Haemoproteus pulcher, and we present a Bayesian phylogenetic analysis based on nearly complete mitochondrial genomes of these 2 parasites. Leucocytozoon cariamae n. sp. morphology is consistent with our phylogenetic analysis indicating that it does not share a recent common ancestor with the L. fringillinarum group. Haemoproteus pulcher and Haemoproteus catharti form a monophyletic group with Haemocystidium parasites of Reptilia, supporting the polyphyly of the genus Haemoproteus. We also discussed the hypothesis that H. pulcher and H. catharti may be avian Haemocystidium, highlighting the need to study non-passerine parasites to untangle the systematics of Haemosporida.
Assuntos
Doenças das Aves , Coinfecção , Genoma Mitocondrial , Haemosporida , Parasitos , Infecções Protozoárias em Animais , Animais , Filogenia , Brasil/epidemiologia , Teorema de Bayes , Infecções Protozoárias em Animais/parasitologia , Doenças das Aves/parasitologia , Haemosporida/genética , Parasitos/genética , AvesRESUMO
PURPOSE: Cavity shaving (CS) is a surgical technique used in the treatment of breast cancer (BC). It may reduce margin positivity in histologic assessment and consequently reduces re- excision rates in breast conserving surgery (BCS). The evidence for this assumption is described in the present review. METHODS: A systematic review of relevant literature in English from January 1999 to April 2019 was conducted. The analysis included studies on CS and its effects on re-excision rates and margin positivity. We searched PubMed databases for relevant publications. In total, 22 studies were included in the present review. RESULTS: The benefit from CS on re-excision rates and histologic margin positivity was variable. Out of 22 studies, 17 reported a reduction in both re-excision rates and histologic margin positivity in margin shaved patients. Four studies could not find a significant reduction of second surgeries and residual tumor rates. One study suggested that CS after BCS was superior to single BCS only in subgroup analysis in IDC tumors. CONCLUSION: CS is a surgical technique that was shown to reduce re-excision and margin positivity rates in most of the studies. Furthermore, it can be a useful tool to assess specimen margins and detect multifocality.
Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Feminino , Humanos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Mastectomia Segmentar/métodos , Neoplasia Residual/patologia , Reoperação , Estudos RetrospectivosRESUMO
While general mechanisms by which Plasmodium ookinetes invade the mosquito midgut have been studied, details regarding the interface of the ookinete, specifically its barriers to invasion, such as the proteolytic milieu, the chitin-containing, protein cross-linked peritrophic matrix, and the midgut epithelium, remain to be understood. Here, we review our knowledge of Plasmodium chitinases and the mechanisms by which they mediate ookinetes crossing the peritrophic matrix. The integration of new genomic insights into previous findings advances our understanding of Plasmodium evolution. Recently obtained Plasmodium species genomic data enable identification of the conserved residues in the experimentally demonstrated hetero-multimeric, high-molecular-weight complex comprised of a short chitinase covalently linked to binding partners, von Willebrand factor A domain-related protein (WARP) and secreted ookinete adhesive protein (SOAP). Artificial intelligence-based high-resolution structural modeling using the DeepMind AlphaFold algorithm yielded highly informative three-dimensional structures and insights into how short chitinases, WARP, and SOAP may interact at the atomic level to form the ookinete-secreted peritrophic matrix invasion complex. Elucidating the significance of the divergence of ookinete-secreted micronemal proteins among Plasmodium species may lead to a better understanding of the ookinete invasion machinery and the coevolution of Plasmodium-mosquito interactions.
Assuntos
Quitinases/metabolismo , Culicidae/parasitologia , Interações Hospedeiro-Parasita , Micronema/metabolismo , Complexos Multiproteicos/metabolismo , Plasmodium/fisiologia , Animais , Evolução Biológica , Quitinases/genética , Sistema Digestório/parasitologia , Modelos Biológicos , Modelos Moleculares , Peso Molecular , Complexos Multiproteicos/química , Filogenia , Plasmodium/classificação , Conformação Proteica , Especificidade da Espécie , Relação Estrutura-AtividadeRESUMO
Among the primate malaria parasites, those found in lemurs have been neglected. Here, six Plasmodium lineages were detected in 169 lemurs. Nearly complete mitochondrial genomes (mtDNA, ≈6Kb) and apicoplast loci (≈6Kb) were obtained from these parasites and other Haemosporida species. Plasmodium spp. in lemurs are a diverse clade that shares a common ancestor with other primate parasites from continental Africa. Time-trees for the mtDNA were estimated under different scenarios, and the origin of the lemur clade coincides with the proposed time of their host species' most recent common ancestor (Lemuridae-Indriidae). A time tree with fewer taxa was estimated with mtDNA + Apicoplast loci. Those time estimates overlapped but were younger and had narrower credibility intervals than those from mtDNA alone. Importantly, the mtDNA + Apicoplast estimates that the clade including the most lethal malaria parasite in humans, Plasmodium falciparum, may have originated with Homininae (African apes). Finally, the phylogenetic congruence of the lemurs and their parasites was explored. A statistically significant scenario identified four cospeciation, two duplications, four transfer (host-switches), and zero loss events. Thus, the parasite species sampled in lemurs seem to be radiating with their hosts.
Assuntos
Lemur , Lemuridae , Malária , Parasitos , Plasmodium , Animais , DNA Mitocondrial/genética , Lemur/genética , Lemuridae/genética , Malária/genética , Malária/parasitologia , Parasitos/genética , Filogenia , Plasmodium/genética , Primatas/genética , Primatas/parasitologiaRESUMO
The global malaria burden sometimes obscures that the genus Plasmodium comprises diverse clades with lineages that independently gave origin to the extant human parasites. Indeed, the differences between the human malaria parasites were highlighted in the classical taxonomy by dividing them into two subgenera, the subgenus Plasmodium, which included all the human parasites but Plasmodium falciparum that was placed in its separate subgenus, Laverania. Here, the evolution of Plasmodium in primates will be discussed in terms of their species diversity and some of their distinct phenotypes, putative molecular adaptations, and host-parasite biocenosis. Thus, in addition to a current phylogeny using genome-level data, some specific molecular features will be discussed as examples of how these parasites have diverged. The two subgenera of malaria parasites found in primates, Plasmodium and Laverania, reflect extant monophyletic groups that originated in Africa. However, the subgenus Plasmodium involves species in Southeast Asia that were likely the result of adaptive radiation. Such events led to the Plasmodium vivax lineage. Although the Laverania species, including P. falciparum, has been considered to share "avian characteristics," molecular traits that were likely in the common ancestor of primate and avian parasites are sometimes kept in the Plasmodium subgenus while being lost in Laverania. Assessing how molecular traits in the primate malaria clades originated is a fundamental science problem that will likely provide new targets for interventions. However, given that the genus Plasmodium is paraphyletic (some descendant groups are in other genera), understanding the evolution of malaria parasites will benefit from studying "non-Plasmodium" Haemosporida.
Assuntos
Malária Falciparum , Malária , Plasmodium , Animais , Malária/parasitologia , Plasmodium/genética , Plasmodium falciparum/genética , Plasmodium vivax/genéticaRESUMO
We study the electronic transport through an all-carbon quantum ring side-coupled to a quantum wire. We employ both first-principles calculations and a tight-binding approach; the latter allows for the derivation of analytical expressions for the conductance and density of states, which facilitates the interpretation of the transport characteristics. Two bond models are employed: either all the hoppings are equal (cumulenic ring) or they have alternating bonds (polyynic ring). Assuming cumulenic bonds, if the number of atoms in the carbon ring is a multiple of four, it produces an antiresonant peak in the conductance at the Fermi level. This effect disappears for the polyynic configuration, i.e., when the hoppings in the carbon rings are alternating. Additionally, a gap opens at the Fermi energy in the polyynic rings, yielding distinct transport signatures for the two bond configurations. Comparison to first-principles calculations shows an excellent agreement on the changes of the conductance due to the carbon ring. We propose such transport measurements as a way to elucidate the character of the bonds in these novel carbon nanostructures.
RESUMO
The electronic structure of monolayer pentagonal palladium diselenide (PdSe2) is analyzed from the topological band theory perspective. Employing first-principles calculations, effective models and symmetry indicators, we find that the low-lying conduction bands are topologically nontrivial, protected by time reversal and crystalline symmetries. Numerical evidence supporting the nontrivial character of the bands is presented. Furthermore, we obtain a relevant physical response from the topological viewpoint, such as the spin Hall conductivity.
RESUMO
A fruit processing wastewater was submitted to different advanced oxidation processes, namely, electro-Fenton (EF), electrochemical oxidation (EO), activated persulfate (PS), and combined EF/PS. The performance of the treatment processes, at different experimental conditions, regarding organic load removal, biodegradability increment, toxicity reduction, and specific energy consumption (Esp), was evaluated. At the experimental conditions studied, EO led to the treated solutions with the highest biodegradability increment, from 0.24 to 0.48, and toxicity reduction towards Daphnia magna, from 5.8 to 1.5 toxic units, without requiring the addition of chemicals. Nevertheless, the highest chemical oxygen demand (COD) removals were obtained for EF and combined EF/PS treatments. For the electrochemical processes, an increase in COD removal rate with applied current density (j) was observed. However, the increase in j substantially raised the Esp. In PS treatment, COD removals above 80% were only achieved for high amounts of added persulfate and iron, which led to less biodegradable and more toxic solutions. Combined EF/PS attained the lowest Esp values, mainly due to the conductivity increase originated by the persulfate and iron salts addition. Besides the disadvantage of the chemicals added, this combined treatment led to treated solutions with very acidic pH and significant iron content.
Assuntos
Águas Residuárias , Poluentes Químicos da Água , Análise da Demanda Biológica de Oxigênio , Frutas/química , Peróxido de Hidrogênio , Oxirredução , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Águas Residuárias/toxicidade , Poluentes Químicos da Água/análiseRESUMO
OBJECTIVE: Patients with nonmelanoma skin cancer (NMSC)-ie, basal cell carcinoma (BCC) or squamous cell carcinoma (SCC)-have an increased risk of developing a second skin cancer. The aim of this study was to describe the frequency, incidence per 1000 person-years, and predictors of a second skin cancer in a cohort of patients with NMSC treated with Mohs micrographic surgery (MMS). MATERIAL AND METHODS: Prospective study of a national cohort of patients with NMSC who underwent MMS at 22 Spanish hospitals between July 2013 and February 2020; case data were recorded in the REGESMOHS registry. The study variables included demographic characteristics, frequency and incidence per 1000 person-years of second skin cancers diagnosed during the study period, and risk factors identified using mixed-effects logistic regression. RESULTS: We analyzed data for 4768 patients who underwent MMS; 4397 (92%) had BCC and 371 (8%) had SCC. Mean follow-up was 2.4 years. Overall, 1201 patients (25%) developed a second skin cancer during follow-up; 1013 of the tumors were BCCs (21%), 154 were SCCs (3%), and 20 were melanomas (0.4%). The incidence was 107 per 1000 person-years (95% CI, 101-113) for any cancer, 90 per 1000 person-years (95% CI, 85-96) for BCC, 14 (95% CI, 12-16) per 1000 person-years for SCC, and 2 (95% CI, 1-3) per 1000 person-years for melanoma. More men than women developed a subsequent skin cancer (738 [61%] vs 463 [39%]). The main risk factors were a history of multiple tumors before diagnosis (relative risk [RR], 4.6; 95% CI, 2.9-7.1), immunosuppression (RR, 2.1; 95% CI, 1.4-3.1), and male sex (RR, 1.6; 95% CI, 1.4-1.9). CONCLUSION: Patients have an increased risk of developing a second tumor after MMS treatment of NMSC. Risk factors are a history of multiple tumors at diagnosis, immunosuppression, and male sex.
Assuntos
Carcinoma Basocelular , Carcinoma de Células Escamosas , Melanoma , Neoplasia de Células Basais , Neoplasias Cutâneas , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/patologia , Carcinoma Basocelular/cirurgia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Estudos de Coortes , Feminino , Humanos , Masculino , Melanoma/complicações , Cirurgia de Mohs , Estudos Prospectivos , Fatores de Risco , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/cirurgiaRESUMO
Universities are encouraging the implementation of innovative methodologies and teaching strategies to develop an interactive and appealing educational environment where students are the focus of the learning process. In such a personalised learning environment, an increase of the students' engagement and the improvement of the outcomes arise. MathE has been developed to help achieve this goal. Based on collaborative procedures, internet resources - both pre-existing and freely available as well as resources specifically conceived by the project team - and communities of practices, MathE intends to be a tool to nurture and stimulate the learning of Mathematics in higher education. This study introduces and describes the MathE platform, which is divided into three sections: Student's Assessment, Library and Community of Practice. An in-depth description of the Student's Assessment section is presented and an analysis of the results obtained from students, when using this feature of the platform, is also provided. After this, and based on the answers to an online survey, the impact of the MathE platform among students and teachers of eight countries is shown. Although the number of collected results is still scarce, it allows the recognition of a trend regarding the use of the material of the Student's Assessment section for autonomous study. The results indicate the platform is well organized, with a satisfactory amount and diversity of questions and good interconnection between the various parts. Nevertheless, both teachers and students indicate that more questions should be introduced. The overall opinion about the MathE platform is very favourable.
RESUMO
Apicomplexa is a phylum of parasitic protozoa; among them are the order Haemosporida, vector-borne parasites that include those that cause malaria (genus Plasmodium). Most Apicomplexa species have a non-photosynthetic plastid or apicoplast. Given its unique metabolic pathways, this organelle is considered a target for malaria therapeutics. Regardless of its importance, there is a paucity of complete apicoplast genome data hindering comparative studies. Here, the Haemoproteus (Haemoproteus) columbae apicoplast genome (lineage HAECOL1) was obtained using next-generation sequencing. This genome was included in a comparative analysis with other plastids. This 29.8 kb circular genome shares the same structure found in Plasmodium parasites. It is A + T rich (87.7%), comparable but at the higher end of A + T content observed in Plasmodium species (85.5-87.2%). As expected, considering its high A + T content, the synonymous codon usage (RSCU) and the effective number of codons (ENc) showed a moderate codon bias. Several apicoplast genes have a phylogenetic signal. However, unlike mitochondrial genes, single-gene phylogenies have low support in haemosporidian clades that diverged recently. The H. columbae apicoplast genome suggests that the apicoplast function may be conserved across Haemosporida. This parasite could be a model to study this organelle in a non-mammalian system.
Assuntos
Apicoplastos/genética , Haemosporida/citologia , Filogenia , Plasmodium/parasitologiaRESUMO
BACKGROUND: Venezuela accounted for 55% of the cases and 73% of the malaria deaths in the Americas in 2019. Bolivar state, in the southeast, contributes > 60% of the country's Plasmodium vivax and Plasmodium falciparum cases every year. This study describes the clinical-epidemiological characteristics of clinical malaria patients in this high-transmission area. METHODS: A prospective study was conducted on patients seeking medical attention in three medical centres in the state capital, Ciudad Bolivar, between June and October 2018. Malaria diagnosis was carried out using microscopy following national standards. Malaria-positive patients were examined for clinical symptoms, and haematological tests were performed at the time of diagnosis. Patients were followed up by telephone to evaluate malaria recurrences. RESULTS: Out of 287 patients, 200 (69.7%) were positive for P. vivax, 69 (24%) for P. falciparum, and 18 (6.3%) had mixed (P. vivax/P. falciparum) infections. Patients' median age was 33 years (IQR 20), 168 (69%) were men, and 40% practiced gold mining as the main occupation. Fever (96.5%), chills (91.3%), and headaches (90.6%) were the most frequent symptoms. At least one symptom associated with severe malaria was observed in 69 out of 161 patients with complete clinical evaluation (42.9%). Plasmodium vivax infections were found in 42 out of 69 (60.9%) severe cases; by contrast, P. falciparum and mixed malaria caused 34.8% (24/69) and 4.4% (3/69) of infections, respectively. Two patients died of cerebral malaria. Mean hemoglobin was lower in the patients infected with P. falciparum than those infected with P. vivax. Regardless of the parasite causing the infection, patients presented high levels of total bilirubin, aminotransferases (AST, ALT), and lactate dehydrogenase (LDH). Out of the 142 patients followed up by phone for three months (49.5% of the 287 patients), 35 (24.7%) reported recurrences. CONCLUSIONS: The high malaria prevalence among young male adults practicing gold mining suggests that this occupation is a significant risk factor. The unexpected high prevalence of P. vivax patients with at least one criteria of severe clinical disease is a matter of concern. Whether it is the result of a lack of timely diagnosis and effective treatment should be explored.
Assuntos
Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Doenças Profissionais/epidemiologia , Plasmodium falciparum/fisiologia , Plasmodium vivax/fisiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Mineração , Doenças Profissionais/parasitologia , Prevalência , Fatores de Risco , Venezuela/epidemiologia , Adulto JovemRESUMO
Delimiting and describing Plasmodium species in reptiles remains a pressing problem in Haemosporida taxonomy. The few morphological characters used can overlap, and the significance of some life-history traits is not fully understood. Morphologically identical lizard Plasmodium forms have been reported infecting different cell types (red and white blood cells) in the same host and have been considered the same species. An example is Plasmodium tropiduri tropiduri, a species known to infect erythrocytes, thrombocytes and lymphocyte-like cells. Here, both forms of P. t. tropiduri were analysed using light microscope-based morphological characteristics and phylogenetic inferences based on almost complete mitochondrial genomes of parasites naturally infecting lizards in southeastern Brazil. Although morphologically similar, two distinct phylogenetic lineages infecting erythrocytes and non-erythrocytic cells were found. The lineage found in the erythrocytes forms a monophyletic group with species from Colombia. However, the non-erythrocytic lineage shares a recent common ancestor with Plasmodium leucocytica, which infects leucocytes in lizards from the Caribbean islands. Here, Plasmodium ouropretensis n. sp. is described as a species that infects thrombocytes and lymphocyte-like cells.