Development of a portable label-free electrochemical sensor modified with AuNPs/g-C3N4@CTAB for uric acid detection in complex blood samples Fernando C. Gallina, Igor. G. S. Oliveira, Muriel A. Rodrigues, Luís F. Basso, Oswaldo C. Junior, Beatriz T. Marin, Robson S. Souto, Leandro M. C. Pinto, Herintha C. Neitzke-Abreu, Thalles P. Lisboa, Marcos R. V. Lanza, Willyam R. P. Barros Microchimica Acta, 2026 The development and application of a lab-made screen-printed electrode (SPE) modified with electrodeposited gold nanoparticles (AuNPs), graphitic carbon nitride (g-C3N4) and cetyltrimethylammonium bromide (CTAB) for the electrochemical determination of uric acid (UA) is reported. The SPE/AuNPs/g-C3N4@CTAB platform was optimized to enhance its electroactive surface area, conductivity, and charge-transfer kinetics, as confirmed through scanning electronic microscopy, energy-dispersive x-ray spectroscopy, Raman spectroscopy, contact angle analysis, cyclic voltammetry, and electrochemical impedance spectroscopy. Differential pulse voltammetry measurements demonstrated a linear response for UA concentrations between 50 and 600 µmol L⁻¹, with a limit of detection of 1.95 µmol L⁻¹, fully covering clinically relevant ranges. The sensor exhibited high selectivity against common interferents, as well as excellent stability and optimal performance at physiological pH of 7.0, consistent with UA dissociation equilibria. The application of the SPE/AuNPs/g-C3N4@CTAB sensor for UA detection in human whole blood, serum, and plasma samples showed promising results comparable to those obtained from standard enzymatic colorimetric assays, confirming the analytical reliability of the device. The computational analysis by DFT calculations demonstrated that the Eads of UA to the complete modified sensor decreased at − 0.23 eV when compared to the SPE/AuNPs/g-C3N4. This reduction provides strong theoretical evidence supporting the influence of the CTAB modifier on the UA detection mechanism. Overall, the proposed modified SPE platform provides a simple, cost-effective, and portable alternative tool for UA monitoring in clinical samples.
Characterization of sand fly (Diptera: Psychodidae: Phlebotominae) fauna and potential hosts of Leishmania in a military area of Dourados, Mato Grosso do Sul, Brazil Iara Beatriz Andrade de Sousa, Gabriel Barbosa Costa, Walderson Zuza Barbosa, Karen Araújo Magalhães, Kamily Fagundes Pussi, Marco Aurélio Louveira Areco, Salvador Paganella Chaves Júnior, Paulo Silva de Almeida, Manoel Sebastião da Costa Lima Junior, Herintha Coeto Neitzke-Abreu Journal of Medical Entomology, 2026 We investigated the sand fly fauna and the presence of Leishmania spp. DNA in collected specimens, domestic animals, and military personnel. The 4th Mechanized Cavalry Brigade of Dourados, Mato Grosso do Sul, Brazil is located in an area that has characteristics conducive to the life cycle of Leishmania spp. An epidemiological questionnaire applied to military personnel, and whole blood samples were collected from them and domestic animals. Using the collected blood samples, PCR (Polymerase Chain Reaction) and serology tests were performed to detect Leishmania spp. DNA and anti-Leishmania antibodies, respectively. Additionally, CDC (Center on Disease Control) traps were installed at eight points over 12 months. In total, 652 sand flies belonging to 9 genera and 19 species were collected. Lutzomyia longipalpis, which is the main vector of Leishmania infantum, the etiological agent of visceral leishmaniasis was present in half of the collection points. The DNA detection rate of Leishmania spp. was 0.31% (one pool of Psathyromyia aragaoi and one pool of Brumptomyia spp.). We analyzed 35 animals (dogs and horses) and 235 military personnel. Analysis of samples from animals and soldiers was negative for Leishmania spp. About 30.2% (n = 71) of military personnel did not know about leishmaniasis. Although some vector species were found, no Leishmania spp. DNA was identified in species of medical and veterinary importance. The area investigated showed characteristics that can contribute to the proliferation of the vector and the spread of the disease. Long-term monitoring studies and activities that increase awareness in the population should be encouraged by research funding bodies and leishmaniasis surveillance and control programs.
Evaluation of a new rapid diagnostic test, based on the chimeric protein Q5, for the diagnosis of human and canine forms of visceral leishmaniasis Wagner José Tenório dos Santos, Natalia Rocha Nadaes, Allana Kelly Oliveira Dutra, Adalúcia da Silva, Hemilly Rayanne Ferreira da Silva, et al. Memorias do Instituto Oswaldo Cruz, 2026 BACKGROUND: Visceral leishmaniasis (VL), caused by Leishmania infantum, is the most severe form of leishmaniasis, prevalent in many countries, but still with limitations in diagnosis for both human and canine hosts. Serological assays based on recombinant proteins are the most efficient diagnostic alternatives, with the rapid diagnostic test (RDT) being the most cost-effective. The previously described chimeric Q5 is a recombinant protein derived from three native L. infantum antigens, which is potentially useful for both human and canine VL diagnosis, through preliminary enzyme-linked immunosorbent assay (ELISA), but which was not evaluated within an RDT setting. OBJECTIVES: To evaluate the diagnostic performance of the chimeric recombinant protein Q5 in both ELISA and RDT formats for the detection of human and canine VL, and to compare its performance with RDTs based on Lci2 and Lci13 antigens. METHODS: Here, we first expanded the Q5 evaluation through ELISA with a larger set of human and canine VL-positive sera from multiple origins. We confirmed a sensitivity ranging between 80% and 90% for the human VL and greater than 90% with the canine VL sera. A new RDT-Q5 was then set up and tested with multiple batches of human and canine sera. FINDINGS: An improved performance was seen for the human VL diagnosis (94% sensitivity), but it was reduced with canine sera (86% sensitivity). Specificity values for both the ELISA-Q5 and RDT-Q5 were generally greater than 95%, with limited (8%) or no false-positive results with human sera from individuals with cutaneous leishmaniasis (CL) and Chagas disease (CD), respectively. The RDT-Q5 performance was compared with RDTs based on two other recombinant proteins, Lci2 and Lci13, tested respectively for the human and canine VL diagnosis. MAIN CONCLUSIONS: Despite an equivalent performance for the human VL diagnosis, the RDT-Lci2 led to a much greater incidence of false-positive results with the CL and CD sera. In contrast, no setup for the RDT-Lci13 was effective with the canine sera. Our results confirm the RDT-Q5 as an efficient alternative for the VL diagnosis in the field, particularly for the human form of the disease.
OVITRAP-BASED MONITORING AND INFESTATION ANALYSIS OF Aedes aegypti IN BRAZIL Paulo Silva de Almeida, Leticia Bueno De Moura, Iara Beatriz Andrade de Sousa, Marcos Gino Fernandes, Gustavo Vinício Pupo, Leandro Soares de Souza, Herintha Coeto Neitzke Abreu Journal of Tropical Pathology, 2025 Aedes aegypti has been the primary vector of dengue transmission since the 17th century. This study aimed to analyze the infestation index of Ae. aegypti in the municipality of Itaquiraí, Mato Grosso do Sul, Brazil, using ovitrap-based monitoring. Weekly ovitrap collections were conducted in five urban neighborhoods from March 2015 to December 2018. Two key entomological indicators were analyzed: the Egg Density Index (EDI) and the Ovitrap Positivity Index (OPI). A total of 62,198 Ae. aegypti eggs were collected, with 29.7% of traps testing positive. The overall EDI was 35.2%, peaking in April (48.8%). The highest annual EDI was recorded in 2015 (55.3%). Annual OPI values were 75.9% in 2015, 24.4% in 2016, 15.4% in 2017, and 16.2% in 2018. Monthly OPI peaks occurred in April (2015), February (2016), and January (2017 and 2018). The Poisson distribution (λ = 4.50) suggested a mean of 4.5 eggs per trap per sampling period. The Negative Binomial distribution (r = 0.36, p = 0.07) indicated an aggregated dispersion pattern. The Log-Normal distribution parameters (shape = 1.32, location = 18.00, scale = 0.00) revealed that a small proportion of traps accounted for high egg densities. The study concludes that oviposition varied substantially across the monitoring period and was spatially clustered. The period of highest transmission risk occurred from January to April. Environmental and climatic factors, alongside consistent control and monitoring actions, are critical for reducing vector populations. Entomological surveillance using ovitraps, combined with community awareness campaigns, constitutes an essential strategy for guiding preventive and vector control measures. KEY WORDS: Surveillance; insect traps; mosquitoes; arboviruses, dengue.
Aedes Aegypti AND Aedes Albopictus (DIPTERA: CULICIDAE) IN ARTIFICIAL BREEDING SITES IN RURAL SETTLEMENTS AND INDIGENOUS VILLAGES Paulo Silva de Almeida, José Pedro Moreira Carneiro, Tamara Nunes Lima‐Camara, Márcia Bicudo de Paula, Eduardo José de Arruda, et al. Journal of Tropical Pathology, 2024 Aedes aegypti and Aedes albopictus are vectors for different arboviruses. Ae. aegypti is more common in urban areas, where it uses water collected within artificial receptacles to lay its eggs, Ae. albopictus is more prevalent in areas with greater vegetation cover, in which natural water bodies serve as breeding sites for the immature forms. Despite the importance of these two species in Brazil, little is currently known regarding their presence in rural settlements and indigenous villages. In this study, we describe the occurrence of the larvae and pupae of Ae. aegypti and Ae. albopictus in artificial breeding sites in rural settlements and indigenous villages located in municipalities in Mato Grosso do Sul, Brazil. Collections were carried out in seven rural settlements and two indigenous villages, mainly in 2018. At each location, different households were randomly selected and the artificial peridomestic containers were inspected for the presence of larvae and pupae. Immature forms were collected at all nine rural locations, and 64 of the 173 households were investigated (36.99%, 95% CI, 30.04–44.38). A total of 8744 specimens were collected, among which Ae. aegypti was identified as the predominant species, followed by Culex spp. Ae. albopictus, Limatus spp., and Anopheles spp. These findings can contribute to the development of more effective control strategies for Ae. aegypti and Ae. albopictus, and encourage the maintenance of active and continuous entomological surveillance in these areas, given that these mosquitoes serve as vectors in the transmission cycle of arboviruses with public health importance. KEYWORDS: Culicidae; vector; arbovirus; control; breeding sites
Feline immunodeficiency virus, feline leukemia virus and Leishmania spp. prevalence in cats from shelters in Mato Grosso do Sul, Brazil Walderson Zuza Barbosa, Karen Araújo Magalhães, Kamily Fagundes Pussi, Manoel Sebastião da Costa Lima, Herintha Coeto Neitzke-Abreu Revista Brasileira De Parasitologia Veterinaria, 2024 Diseases such as those caused by feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) represent health problems for cats. Feline leishmaniasis (FL) has been reported in several cities across the country. The objective was to carry out a clinical-epidemiological and laboratory study of FIV, FeLV and FL in cats from shelters in Dourados, Mato Grosso do Sul, Brazil. Blood samples and swabs from the conjunctival and nasal mucosa were obtained from 75 cats, from four animal shelters. Serology for FIV and FeLV was performed. For Leishmania, polymerase chain reaction (PCR) was performed on blood, conjunctiva and nasal mucosa. In the immunochromatographic serological test, seven cats tested positive for FIV and none for FeLV. No samples was positive in PCR for Leishmania. The study showed that despite the presence of human and canine leishmaniasis in the studied region, Leishmania spp. were absent in the cats studied. To avoid an increase in contagion in shelters, it is essential isolate cats with FIV.
Nano-encapsulated Cu(II) complex as a promising insecticidal for Aedes aegypti (Diptera: Culicidae) Eduardo José de Arruda, Glenda Biasotto, Marisa Masumi Beppu, Fernando Jorge Monteiro, Pedro L. Granja, Maria Rangel, Andreia Leite, Isaías Cabrini, Tiago Santos, Daniel A. Gonçalves, Herintha Coeto Neitzke Abreu Heliyon, 2024 Nanoparticle (NP) research is an area of scientific interest with high potential for application in biomedical, optical, and electronic fields. Due to their relatively large surface area compared to their mass, NPs can be more chemically reactive and change their reactive strength or other properties. NP-based drug delivery systems provide transport and an effective and controlled way to release the drugs. This work aimed to study the solubility and biological activity of nano-encapsulated copper metal complexes for the induction of toxicity and mortality in larvae of Aedes aegypti mosquitoes. After the nano-encapsulated metal complexes were prepared, the efficiency of this incorporation was determined by electron paramagnetic resonance, and toxicity bioassays were performed. The polymeric-based PLGA NPs encapsulating metal complexes exhibited high toxicity and specificity for target organisms (insect vectors, i.e., A. aegypti ), with relatively less environmental impact and long-term control of their breeding.
Maternal transfer of anti-SARS-CoV-2 antibodies through immunization and breastfeeding for 12 months Carolina Rangel de Lima Santos, Kamily Fagundes Pussi, Iara Beatriz Andrade de Sousa, Manoel Sebastião da Costa Lima Junior, Herintha Coeto Netitzke-Abreu Medicina Brazil, 2024 In February 2023, according to the World Health Organization, there had been more than 700 million cases of COVID-19 worldwide. Maternal immunization has become a hotspot in researchon the transplacental transfer of antibodies to the fetus. Vaccinations administered during pregnancy are intended to protect the mother from serious illness. Case presentation: In this report, we describe a case wherein the transfer of anti-SARS-CoV-2 antibodies to the fetus, baby, and infant was observed through immunization and breastfeeding. Maternal antibodies were detected in the umbilical cord at birth, in breast milk for up to 10 mo after birth, and in the child’s blood for up to 1 y of age, which suggests the importance of vaccination during pregnancy as well as maternal and neonatal protection. Conclusion: When an vaccine was administered to the pregnant patient, effective immunological results were obtained in terms of both placental transfer and breastfeeding, for up to 1 y of age.
An Epidemiological Assessment of SARS-CoV-2 in the Sewage System of a Higher Education Institution Carmem Cícera Maria da Silva, Carolina Rangel de Lima Santos, Eliomar Pivante Céleri, David Salles, Julia Miranda Fardin, Kamily Fagundes Pussi, Daniel Claudio de Oliveira Gomes, Vinicius de Oliveira Ribeiro, Leila Cristina Konrad-Moraes, Herintha Coeto Neitzke-Abreu, Valdemar Lacerda Júnior Annals of Global Health, 2024 Background: The World Health Organization declared the end of the COVID-19 pandemic in May 2023, three years after the adoption of global emergency measures. Monitoring of SARS-CoV-2 in sewage underscores its importance due to its effectiveness and cost-effectiveness, highlighting the need to prioritize research on water resources and sanitation. Objectives: The aim of this study was to conduct an epidemiological assessment of SARS-CoV-2 in the sewage system of a higher education institution located in Vitória Espírito Santo State, Maruípe campus. Methods: Over a period of 66 days, from February 6 to April 12, 2023, 15 samples were collected. Each sample consisted of 1 L, collected in 1 hour, with 250 mL collected every 15 minutes. The samples were characterized by assessing their appearance, and pH was measured using a Horiba U-50 multiparameter probe. The extracted RNA was subjected to RT-qPCR using the Allplex™ 2019-nCovAssay Seegene kit. Results: The samples exhibited a cloudy appearance with impurities, and the pH ranged from 6.35 to 8.17. Among the evaluated samples, SARS-CoV-2 RNA was detected in two, and, by comparing this with the epidemiological bulletin issued by the State Health Department, an increase in cases in the state was observed during the collection period of these samples. Conclusions: Sewage monitoring proved to be an important tool in this post-pandemic period, serving as an alert and prevention mechanism for the population in relation to new outbreaks. Furthermore, it represents a low-cost mapping strategy and extensive testing of a population, aligning with the studies presented at the beginning of the pandemic. We recommend specific adjustments considering distinct populations.
Limitation of Primers Used in PCR for the Characterization of Leishmania infantum Helton Krisman de Araújo, Silvana de Oliveira Castro, Maria Joelma Alves da Silva Valejo, Manoel Sebastião da Costa Lima Junior, Herintha Coeto Neitzke-Abreu Journal of Parasitology, 2023 Conventional PCR provides Leishmania species characterization with even a small amount of biological material. Species-specific primers have been a widely used alternative; however, nonspecific amplifications are a reality, interfering with PCR efficiency. In endemic areas with multiple etiological agents for leishmaniasis, there is a requirement for higher specificity of primers. This study evaluates 3 pairs of primers described for the identification and characterization of Leishmania infantum. Primers RV1/RV2, LEISH1/LEISH2, and FLC2/RLC2 were used with the DNA of L. infantum, Leishmania amazonensis, and Leishmania braziliensis. An initial temperature curve was performed (52-62 C) to determine the optimal annealing temperature, followed by a dilution curve of Leishmania DNA (500 pg/μl, 50 pg/μl, 5 pg/μl, 500 fg/μl, 50 fg/μl, 5 fg/μl, and 0.5 fg/μl) to be used for analytical sensitivity. RV1/RV2 PCR amplified L. infantum and L. amazonensis at all analyzed temperatures; LEISH1/LEISH2 PCR amplified all 3 species of Leishmania, although at some temperatures L. infantum was specifically amplified, and, finally, FLC2/RLC2 PCR amplified only L. infantum at all temperatures analyzed. In terms of sensitivity, RV1/RV2 PCR detected 1 fg of L. infantum DNA and 100 pg of L. amazonensis DNA; LEISH1/LEISH2 PCR detected 1 fg of L. infantum DNA, 100 fg of L. amazonensis DNA, and 10 fg of L. braziliensis DNA; and FLC2/RLC2 PCR detected 10 fg of L. infantum DNA. Thus, PCR with FLC2/RLC2 primers is best suited for the molecular characterization of L. infantum, especially in areas where there is an incidence of more than 1 Leishmania species, such as South America.
Asymptomatic Leishmania infection in humans: A systematic review Milena Menezes Corrêa Pederiva, Sidney Mariano dos Santos, Liz Graciela Sanabria Rivarola, Victor Jorge Guerreiro, Katiana Simões Lopes, Manoel Sebastião da Costa Lima Junior, Herintha Coeto Neitzke-Abreu Journal of Infection and Public Health, 2023
Diagnosis of canine leishmaniasis using ear blood PCR in region of Brazil Herintha Coeto Neitzke-Abreu, Victor Bruno Duarte Vieira, Ana Paula Stefanello da Silveira, Leticia Surian Batalini, Laísa Vieira Gnutzmann, Silvana de Oliveira Castro, Silvia Barbosa do Carmo, Elisabete Friozi, Manoel Sebastião da Costa Lima-Junior Advances in Animal and Veterinary Sciences, 2020
Asymptomatic leishmania infection in blood donors from a major blood bank in northeastern Brazil: A cross-sectional study Lucas Portela Silva, Silvia Montenegro, Roberto Werkauser, Kamila Gaudêncio da Silva Sales, Fábia Carla Silva Soares, Vlaudia Maria Assis Costa, Ana Cristina Bezerra, Maria Betania do Amaral Pinto, Suzany Maria Ferreira, Herintha Coeto Neitzke-Abreu, Filipe Dantas-Torres, Manoel Sebastião da Costa Lima Junior Revista do Instituto De Medicina Tropical De Sao Paulo, 2020
The sand fly species (Diptera: Psychodidae) in an urban environment of Mato Grosso do Sul, Brazil Paulo Silva de Almeida, Talita Moreira Silva, Rosilene Francisca Moreira, Vanessa Fukuda Mariano, Miguel Prudencio Oliveira Neto, Dioelen Virginia Borges Souza de Aquino, Herintha Coeto Neitzke-Abreu, Gustavo Mayr de Lima Carvalho, Jose Dilermando Andrade Filho Journal of Tropical Pathology, 2019
Genetic variability of populations of Nyssomyia neivai in the Northern State of Paraná, Brazil Jaqueline de Carvalho Gasparotto, Magda Clara Vieira da Costa-Ribeiro, Vanete Thomaz-Soccol, Sandra Mara Rodrigues da Silva Liebel, Herintha Coeto Neitzke-Abreu, Kárin Rosi Reinhold-Castro, Edilson Colhera Cristovão, Ueslei Teodoro Revista do Instituto De Medicina Tropical De Sao Paulo, 2017
New primers for detection of Leishmania infantum using polymerase chain reaction Kézia Peres GUALDA, Lílian Mathias MARCUSSI, Herintha Coeto NEITZKE-ABREU, Sandra Mara Alessi ARISTIDES, Maria Valdrinez Campana LONARDONI, Rosilene Fressatti CARDOSO, Thaís Gomes Verzignassi SILVEIRA Revista do Instituto De Medicina Tropical De Sao Paulo, 2015
Evaluation of sandfly control measures Kárin Rosi Reinhold-Castro, Regiane Bertin de Lima Scodro, Alessandra de Cassia Dias-Sversutti, Herintha Coeto Neitzke, Robson Marcelo Rossi, João Balduíno Kühl, Thaís Gomes Verzignassi Silveira, Ueslei Teodoro Revista Da Sociedade Brasileira De Medicina Tropical, 2008
Evaluation of sandfly control measures in northern Paraná State, Brazil Ueslei Teodoro, Demilson Rodrigues dos Santos, Ademar Rodrigues dos Santos, Otílio de Oliveira, Luís Paschoal Poiani, João Balduíno Kühl, Maria Valdrinez Campana Lonardoni, Thaís Gomes Verzignassi Silveira, Wuelton Marcelo Monteiro, Herintha Coeto Neitzke Cadernos De Saude Publica, 2007
Preliminary information on sandflies in the north of Paraná State, Brazil Ueslei Teodoro, Demilson R dos Santos, Ademar R dos Santos, Otílio de Oliveira, Luís Paschoal Poiani, Allan Martins da Silva, Herintha Coeto Neitzke, Wuelton Marcelo Monteiro, Maria V Campana Lonardoni, Thaís G Verzignassi Silveira Revista De Saude Publica, 2006
Evaluation of sandfly control in Lobato municipality, Paraná State, southern Brazil Ueslei Teodoro, Demilson Rodrigues dos Santos, Ademar Rodrigues dos Santos, Otílio de Oliveira, Elcio Silvestre dos Santos, Herintha Coeto Neitzke, Wuelton Marcelo Monteiro, Robson Marcelo Rossi, Maria Valdrinez Campana Lonardoni, Thaís Gomes Verzignassi Silveira Cadernos De Saude Publica, 2006
