Verificación del desempeño general del método Elecsys® Chagas en la detección de anticuerpos específicos contra Trypanosoma cruzi / Verification of the general performance of the Elecsys® Chagas method in the detection of specific antibodies against Trypanosoma cruzi

Resumen La enfermedad de Chagas es una parasitosis producida por Trypanosoma cruzi, prevalente principalmente en el continente americano, y observada en regiones no endémicas, producto de viajes y migraciones. El objetivo de este estudio fue comparar el desempeño del ensayo Elecsys® Chagas (Roche Diagnostics Alemania) (ECLIA) para el diagnóstico de la infección chagásica crónica con el método estándar y evaluar su posible empleo en reemplazo del método automatizado existente. Se estudiaron 77 muestras de sueros pertenecientes a pacientes con diagnóstico presuntivo de enfermedad de Chagas, procesadas por los distintos métodos disponibles en la Sección Parasitología del Hospital Muñiz: inmunoensayo quimioluminiscente de micropartículas (CMIA) (Abbott), enzimoinmunoanálisis de adsorción (ELISA) (Wiener) y hemaglutinación indirecta (HAI) (Lab. Lemos S.R.L.). Los resultados de los métodos ELISA y HAI fueron comparados con los obtenidos en la prueba ECLIA, y estos a su vez con el método automatizado disponible. De las muestras analizadas, 22 (28,57%) presentaron IgG anti-T. cruzi y 55 (71,43%) resultaron negativas. Con el método ECLIA se logró un 100% en los parámetros de desempeño, con diferencias en los intervalos de confianza. La razón de verosimilitud positiva y la razón de verosimilitud negativa clasificaron al ensayo como excelente y la potencia global del test apoyó esa afirmación. Los métodos inmunológicos automatizados ayudan a la performance diagnóstica en la etapa crónica de la enfermedad de Chagas, permiten minimizar errores, favorecen la velocidad de emisión de los resultados y, debido a su alta sensibilidad y especificidad, en ciertos escenarios podrían proponerse para usar como única técnica.

Abstract Chagas disease is a parasitosis caused by Trypanosoma cruzi, prevalent mainly in the American continent, and observed in non-endemic regions as a result of travel and migration. The objective of this study was to compare the performance of the Elecsys® Chagas (Roche Diagnostics Alemania) (ECLIA) assay for the diagnosis of chronic Chagas infection with the diagnostic standard, and to evaluate its possible use as a replacement for the existing automated method. A total of 77 serum samples belonging to patients with a presumptive diagnosis of Chagas disease were evaluated, processed by the different methods available in the Parasitology Section of Hospital Muñiz: microparticle chemiluminescent immunoassay (CMIA) (Abbott), enzyme-linked immunosorbent assay (ELISA) (Wiener) and indirect hemagglutination (HAI) (Lab. Lemos S.R.L). The results of the ELISA and HAI methods were compared with those obtained in the ECLIA test, and these in turn with the available automated method. Of the samples analysed, 22 (28.57%) presented IgG anti-T. cruzi and 55 (71.43%) were negative. With the ECLIA method, 100% was achieved in the performance parameters, with differences in the confidence intervals. The positive likelihood ratio and the negative likelihood ratio classify the essay as excellent, and the overall power of the test supports this statement. Automated immunological methods help diagnostic performance in the chronic stage of Chagas disease, allow minimising errors, favour the speed of issuance of results, and due to the high sensitivity and specificity, in certain scenarios, they could be proposed for use as single technique.

Resumo A doença de Chagas é uma parasitose causada pelo Trypanosoma cruzi, prevalente principalmente no continente americano, e observada em regiões não endêmicas em decorrência de viagens e migrações. O objetivo deste estudo foi comparar o desempenho do ensaio Elecsys® Chagas (Roche Diagnostics Alemanha) (ECLIA) para o diagnóstico da infecção crônica de Chagas com o método padrão e avaliar seu possível uso em substituição do método automatizado existente. Foram avaliadas 77 amostras de soro pertencentes a pacientes com diagnóstico presuntivo de doença de Chagas, processadas pelos diferentes métodos disponíveis na Seção de Parasitologia do Hospital Muñiz: imunoensaio quimioluminescente de micropartículas (CMIA) (Abbott), ensaio imunoenzimático de adsorção (ELISA) (Wiener) e hemaglutinação indireta (HAI) (Lab. Lemos S.R.L). Os resultados dos métodos ELISA e HAI foram comparados com os obtidos no teste ECLIA, e estes por sua vez com o método automatizado disponível. Das amostras analisadas, 22 (28,57%) apresentaram IgG anti-T. cruzi e 55 (71,43%) foram negativos. Com o método ECLIA, foram obtidos 100% nos parâmetros de desempenho, com diferenças nos intervalos de confiança. A razão de verossimilhança positiva e a razão de verossimilhança negativa classificam o ensaio como excelente, e a potencia geral do teste conformou essa afirmação. Os métodos imunológicos automatizados auxiliam no desempenho diagnóstico na fase crônica da doença de Chagas, permitem minimizar erros, favorecem a rapidez na emissão dos resultados e, devido à alta sensibilidade e especificidade, em determinados cenários, poderiam ser propostos para uso como técnica única.

Confusing a Pollen Grain with a Parasite Egg: Infection or Traditional Medicine?

Camacho & Reinhard stated in the December 2019 issue of the KJP (57: 621-625) that we confused a pollen grain with an Enterobius egg found in the grave of a female adolescent residing in ancient Tehran 7,000 years ago. We want here to clarify and answer to the outlined points in their article.

Estratégia Nacional dos Laboratórios Clínicos 2020-2024 / National Strategy for Clinical Laboratories 2020-2024

Laboratórios clínicos desempenham um papel importante no apoio ao sistema do Serviço Nacional de Saúde, proporcionando saúde de qualidade para a população moçambicana. Como parte deste sistema, os laboratórios trabalham lado a lado com outros sectores para garantir testagem apropriada para o diagnóstico e acompanhamento (monitoria) de várias doenças. A Estratégia Nacional dos Laboratórios Clínicos de Moçambique (ENLC) foi desenvolvida em complementaridade do Plano Estratégico do Sector de Saúde 2014-2019, liderando esforços para fortalecer a rede de laboratórios clínicos em Moçambique e servirá para orientar, harmonizar e coordenar todas acções nacionais e internacionais ao longo dos próximos cinco anos. Sendo os laboratórios clínicos uma área transversal, os Objectivos Estratégicos, Metas, Indicadores e Actividades da ENLC foram desenvolvidos após uma revisão dos planos estratégicos anteriores, políticas e directrizes existentes, avaliações situacionais com envolvimento das partes interessadas e uma reflexão crítica sobre a crescente dependência de serviços laboratoriais de alta qualidade em todo o sistema de saúde. Reconhecendo a complexidade dos serviços laboratoriais de Moçambique, a disponibilidade de financiamento pode afectar o alcance dos Objectivos. Com efeito, solicita-se a todos os intervenientes que utilizam serviços de laboratório para apoiarem na disponibilização de recursos para fortalecer os serviços de diagnóstico laboratorial de qualidade, acessíveis à população moçambicana, com vista a se alcançar progressivamente a Cobertura Universalde Saúde, permitindo deste modo, a todos os moçambicanos, especialmente os mais vulneráveis, desfrutarem da melhor saúde possível. Espera-se também que as propostas de intervenções desta Estratégia sejam incorporadas nos planos dos gestores e implementadores do Sistema Nacional de Saúde de acordo com as responsabilidades que lhe forem conferidas e que sirva de inspiração usando-o no seu dia-a-dia.

Assessing the Parasitic Burden in a Late Antique Florentine Emergency Burial Site.

Excavation (2008-2014) carried out under the Uffizi Gallery (Florence, Italy) led to the discovery of 75 individuals, mostly buried in multiple graves. Based on Roman minted coins, the graves were preliminarily dated between the second half of the 4th and the beginning of the 5th centuries CE. Taphonomy showed that this was an emergency burial site associated with a catastrophic event, possibly an epidemic of unknown etiology with high mortality rates. In this perspective, paleoparasitological investigations were performed on 18 individuals exhumed from 9 multiple graves to assess the burden of gastrointestinal parasitism. Five out of eighteen individuals (27.7%) tested positive for ascarid-type remains; these are considered as "decorticated" Ascaris eggs, which have lost their outer mammillated coat. Roundworms (genus Ascaris) commonly infest human populations under dire sanitary conditions. Archaeological and historical evidence indicates that Florentia suffered a period of economic crisis between the end of 4th and the beginning of the 5th centuries CE, and that the aqueduct was severely damaged at the beginning of the 4th century CE, possibly during the siege of the Goths (406 CE). It is more than plausible that the epidemic, possibly coupled with the disruption of the aqueduct, deeply affected the living conditions of these individuals. A 27.7% frequency suggests that ascariasis was widespread in this population. This investigation exemplifies how paleoparasitological information can be retrieved from the analysis of sediments sampled in cemeteries, thus allowing a better assessment of the varying frequency of parasitic infections among ancient populations.

Paleoparasitology of Merovingian Corpses Buried in Stone Sarcophagi in the Saint-Martin-au-Val Church (Chartres, France).

Paleoparasitological analysis was carried on 4 Merovingian skeletons, dated from the late-5th to the late-9th centuries, and recovered in the church of Saint-Martin-au-Val in Chartres (Center region, France). The corpses were buried in stone sarcophagi, which were still sealed at the time of excavation. Parasite marker extraction was conducted on sediment samples taken from the abdominal and pelvic regions, but also on samples taken from under the head and the feet as control samples. Microscopic observation revealed the presence of 3 gastrointestinal parasites, namely the roundworm (Ascaris lumbricoides), the whipworm (Trichuris trichiura) and the fish tapeworm (genus Diphyllobothrium). This analysis contributes to a better knowledge of the health status and the lifestyle of ancient medieval populations during the Merovingian period, for which very few paleoparasitological data were available, up until now. It demonstrates the presence of the fish tapeworm for the first time during this period.

Confusing a Pollen Grain with a Parasite Egg: an Appraisal of "Paleoparasitological Evidence of Pinworm (Enterobius Vermicularis) Infection in a Female Adolescent Residing in Ancient Tehran".

There is often the risk of confusing pollen grains with helminth eggs from archaeological sites. Thousands to millions of pollen grains can be recovered from archaeological burial sediments that represent past ritual, medication and environment. Some pollen grain types can be similar to parasite eggs. Such a confusion is represented by the diagnosis of enterobiasis in ancient Iran. The authors of this study confused a joint-pine (Ephedra spp.) pollen grain with a pinworm egg. This paper describes the specific Ephedra pollen morphology that can be confused with pinworm eggs.

Comparative study of hatching estimation methods of Rhipicephalus (Boophilus) microplus eggs.

Reproductive parameters of Rhipicephalus (Boophilus) microplus are often evaluated. They are good indicators of resistance to commercial acaricides and of plant extracts' efficacy. The objective of this study was to compare the techniques: visual estimation and quantification by sampling used in the Adult Immersion Test (AIT) to calculate the hatching rate of eggs. Engorged females collected from cattle were subjected to the AIT with plant extracts and kept in an incubator for oviposition. The egg hatching was evaluated in 210 syringes by visual estimation (%). Then, eggs and larvae were counted into samples of 100 individuals, in three repetitions by stereo microscope. Significant differences were found between the two tests (p≤ 0.05). The egg hatching average of visual estimation was higher than the quantification by sampling, 56.8-48.0, respectively (correlation = 0.85). We found that the visual assessment leads to a higher estimate of larvae in relation to eggs, because the infertile eggs can be concealed in the center of the syringe. In quantification by sampling, no statistical differences (p = 0.99) were observed in the pairwise counts between the three samples (48.1 ± 26.6%, 47.8 ± 26.9%, 48.1 ± 26.5%) (correlation of repetitions = 0.96). This suggests that counting one sample is sufficient and the result should not differ much, regardless of the evaluator. Regarding the cutoff point of tick resistance status (95%), both methods are reliable. This study contributes to improvement of the AIT and can stimulate researchers to choose more accurate techniques for the assessment of egg hatching.

Molecular archaeoparasitology identifies cultural changes in the Medieval Hanseatic trading centre of Lübeck.

Throughout history, humans have been afflicted by parasitic worms, and eggs are readily detected in archaeological deposits. This study integrated parasitological and ancient DNA methods with a large sample set dating between Neolithic and Early Modern periods to explore the utility of molecular archaeoparasitology as a new approach to study the past. Molecular analyses provided unequivocal species-level parasite identification and revealed location-specific epidemiological signatures. Faecal-oral transmitted nematodes (Ascaris lumbricoides and Trichuris trichiura) were ubiquitous across time and space. By contrast, high numbers of food-associated cestodes (Diphyllobothrium latum and Taenia saginata) were restricted to medieval Lübeck. The presence of these cestodes and changes in their prevalence at approximately 1300 CE indicate substantial alterations in diet or parasite availability. Trichuris trichiura ITS-1 sequences grouped into two clades; one ubiquitous and one restricted to medieval Lübeck and Bristol. The high sequence diversity of T.tITS-1 detected in Lübeck is consistent with its importance as a Hanseatic trading centre. Collectively, these results introduce molecular archaeoparasitology as an artefact-independent source of historical evidence.

Qualidade microbiológica e parasitológica de amostras de quibe cru comercializado nos Municípios de Balneário Camboriú e Itajaí, SC / Microbiological and parasitological quality of raw quibe samples commercialized in the Municipalities of Balneário Camboriú and Itajaí, SC

O presente estudo objetivou avaliar microbiologicamente e parasitologicamente quibes crus comercializados nos municípios de Balneário Camboriú e Itajaí em Santa Catarina. Amostras de oito estabelecimentos foram submetidas às análises exigidas pela RDC nº 12 de 2001 e complementares: Staphylococcus coagulase positiva, Coliformes a 45°C, Salmonella sp., Coliformes a 35°C, bolores e leveduras, bem como análise parasitológica. Os resultados revelaram que as amostras coletadas estavam contaminadas com Staphylococcus coagulase positiva, porém com valores dentro do permitido pela referida legislação, 25% apresentaram Coliformes a 45°C acima do preconizado e quanto à Salmonella sp., todas estavam em conformidade. Dados das análises complementares apresentaram ausência de cistos, ovos e larvas de parasitos, porém alta contagem de Coliformes a 35°C (100%), bolores e leveduras (75%). Conclui-se que é notória a necessidade de cuidado na preparação deste alimento, treinamento para os manipuladores, aplicação de boas práticas na manipulação dos alimentos, higienização adequada dos equipamentos e utensílios, além da necessidade da reformulação da legislação referente aos padrões microbiológicos existentes para a obtenção de um produto com qualidade objetivando a segurança dos alimentos.

The aim of the present study was to evaluate he uncooked kibbe commercialized in the municipalities of Balneário Camboriú and Itajaí, in Santa Catarina, in their microbiological and parasitological aspect. Samples from eight establishments were submitted to analysis required by RDC nº 12 de 2001 and complementary: coagulase positive Staphylococcus, Coliforms at 45°, Coliforms at 35°, Salmonella sp., molds and yeasts, as well as parasitological analysis. The results showed that the collected samples were contaminated with positive coagulase Staphylococcus, but with values within the limits allowed by the legislation, 25% had Coliforms at 45° higher than recommended and for Salmonella sp., all were in compliance. Data from the complementary analyzes showed absence of cysts, eggs and larvae of parasites, but high counts of coliforms at 35° (100%), molds and yeasts (75%). It is concluded that the need for care in the preparation of this food, training for manipulators, application of good practices, adequate hygiene of equipment and utensils, and the need to reformulate the legislation regarding the existing microbiological standards to obtain a product with quality aiming at food safety.

Ecological Stoichiometry for Parasitologists.

Ecological stoichiometry (ES) is an ecological theory used to study the imbalances of chemical elements, ratios, and flux rates among organisms and the environment to better understand nutrient cycling, energy flow, and the role of organisms in ecosystems. Parasitologists can use this framework to study phenomena across biological scales from genomes to ecosystems. By using the common currency of elemental ratios such as carbon:nitrogen:phosphorus, parasitologists are beginning to explicitly link parasite-host interactions to ecosystem dynamics. Thus, ecological stoichiometry provides a framework for studying the feedbacks of parasites on the environment as well as the effects of the environment on parasites and disease.

Evaluation of in vitro culture systems for the maintenance of microfilariae and infective larvae of Loa loa.

BACKGROUND: Suitable and scalable in vitro culture conditions for parasite maintenance are needed to foster drug research for loiasis, one of the neglected tropical diseases which has attracted only limited attention over recent years, despite having important public health impacts. The present work aims to develop adequate in vitro culture systems for drug screening against both microfilariae (mf) and infective third-stage larvae (L3) of Loa loa. METHODS: In vitro culture conditions were evaluated by varying three basic culture media: Roswell Park Memorial Institute (RPMI-1640), Dulbecco's modified Eagle's medium (DMEM) and Iscove's modified Dulbecco's medium (IMDM); four sera/proteins: newborn calf serum (NCS), foetal bovine serum (FBS), bovine serum albumin (BSA) and the lipid-enriched BSA (AlbuMax® II, ALB); and co-culture with the Monkey Kidney Epithelial Cell line (LLC-MK2) as a feeder layer. The various culture systems were tested on both mf and L3, using survival (% motile), motility (T90 = mean duration (days) at which at least 90% of parasites were fully active) and moulting rates of L3 as the major criteria. The general linear model regression analysis was performed to assess the contribution of each variable on the viability of Loa loa L3 and microfilarie. All statistical tests were performed at 95% confidence interval. RESULTS: Of the three different media tested, DMEM and IMDM were the most suitable sustaining the maintenance of both L. loa L3 and mf. IMDM alone could sustain L3 for more than 5 days (T90 = 6.5 ± 1.1 day). Serum supplements and LLC-MK2 co-cultures significantly improved the survival of parasites in DMEM and IMDM. In co-cultures with LLC-MK2 cells, L. loa mf were maintained in each of the three basic media (T90 of 16.4-19.5 days) without any serum supplement. The most effective culture systems promoting significant moulting rate of L3 into L4 (at least 25%) with substantial maintenance time were: DMEM + BSA, DMEM + NCS, DMEM-AlbuMax®II, DMEM + FBS all in co-culture with LLC-MK2, and IMDM + BSA (1.5%), DMEM + FBS (10%) and DMEM + NCS (5%) without feeder cells. DMEM + 1% BSA in co-culture scored the highest moulting rate of 57 of 81 (70.37%). The factors that promoted L. loa mf viability included feeder cells (ß = 0.490), both IMDM (ß = 0.256) and DMEM (ß = 0.198) media and the protein supplements NCS (ß = 0.052) and FBS (ß = 0.022); while for L. loa L3, in addition to feeder cells (ß = 0.259) and both IMDM (ß = 0.401) and DMEM (ß = 0.385) media, the protein supplements BSA (ß = 0.029) were found important in maintaining the worm motility. CONCLUSIONS: The findings from this work display a range of culture requirements for the maintenance of Loa loa stages, which are suitable for developing an effective platform for drug screening.

Medicinal plants from the Brazilian Amazonian region and their antileishmanial activity: a review / 中西医结合学报

Leishmaniasis, a neglected disease caused by Leishmania protozoans, primarily affects people in tropical and subtropical areas. Chemotherapy based on the use of pentavalent antimonials, amphotericin B, paromomycin, miltefosine and liposomal amphotericin B is currently the only effective treatment. However, adverse effects, long-term treatment and the emergence of parasite resistance have led to the search for alternative treatments. Natural products used in traditional medicine provide an unlimited source of molecules for the identification of new drugs, and the Amazon region has abundant biodiversity that includes several species of plants and animals, providing a rich source of new products and compounds. Although the literature describes numerous promising compounds and extracts for combating Leishmania protozoans, the results of such research have not been embraced by the pharmaceutical industry for the development of new drugs. Therefore, this review focused on the antileishmanial activity of extracts, isolated compounds and essential oils commonly used by the local population in the Brazilian Amazonian region to treat several illnesses and described in the literature as promising compounds for combating leishmaniasis.

Anti-parasitic effects of water-soluble alkaloid fractions from ethanolic extracts of Sophora moorcroftiana seeds in Caenorhabditis elegans / 中国天然药物

Parasite infections of humans and animals remain a major global health problem, with limited choice of drugs being available to the treatment of parasitosis in the clinic. Sophora moorcroftiana (S. moorcroftiana) is a shrub that grows in Tibet Plateau of China. Decoction of the seeds has been used as a traditional Tibetan medicine to treat parasitosis for years. But the anti-parasitic effects of water-soluble fractions in the seeds need further investigation. In the present study, the water-soluble alkaloid fractions (E2) were obtained from S. moorcroftiana seeds by refluxing extraction with 60% ethanol and low polarity fraction (E2-a) and high polarity fraction (E2-b) were subsequently isolated from E2 using column chromatography. As a parasite model, Caenorhabditis elegans (C. elegans) were treated with different fractions and their survivals were recorded. The results showed that that E2-a induced a lower survival rate in C. elegans than E2-b and E2. The protoscoleces of Echinococcus granulosus (E. granulosus) were cultured in the presence of E2-a. Compared with E2-b and E2, protoscoleces exhibited decreased survival rate following E2-a treatment. Furtherly, the effects of E2-a on the behavior, brood size, and lifespan of the worms were investigated. Body bend frequencies of the worms treated with the high concentration of E2-a were reduced by two-thirds compared with the control group (P < 0.01). Compared with non-E2-a-treated group, exposure of nematodes to E2-a led to a decrease in head thrashes and pharyngeal pumps frequency (P < 0.01). E2-a treatment resulted in a significantly lower brood size (P < 0.01). Additional E2-a treatment induced a significantly shortened lifespan, compared with the control (P < 0.05). These findings indicated that water-soluble fraction E2-a from S. moorcroftiana seeds was a potential helminthic agent.

Anti-parasitic effects of water-soluble alkaloid fractions from ethanolic extracts of Sophora moorcroftiana seeds in Caenorhabditis elegans / 中国天然药物

Parasite infections of humans and animals remain a major global health problem, with limited choice of drugs being available to the treatment of parasitosis in the clinic. Sophora moorcroftiana (S. moorcroftiana) is a shrub that grows in Tibet Plateau of China. Decoction of the seeds has been used as a traditional Tibetan medicine to treat parasitosis for years. But the anti-parasitic effects of water-soluble fractions in the seeds need further investigation. In the present study, the water-soluble alkaloid fractions (E2) were obtained from S. moorcroftiana seeds by refluxing extraction with 60% ethanol and low polarity fraction (E2-a) and high polarity fraction (E2-b) were subsequently isolated from E2 using column chromatography. As a parasite model, Caenorhabditis elegans (C. elegans) were treated with different fractions and their survivals were recorded. The results showed that that E2-a induced a lower survival rate in C. elegans than E2-b and E2. The protoscoleces of Echinococcus granulosus (E. granulosus) were cultured in the presence of E2-a. Compared with E2-b and E2, protoscoleces exhibited decreased survival rate following E2-a treatment. Furtherly, the effects of E2-a on the behavior, brood size, and lifespan of the worms were investigated. Body bend frequencies of the worms treated with the high concentration of E2-a were reduced by two-thirds compared with the control group (P < 0.01). Compared with non-E2-a-treated group, exposure of nematodes to E2-a led to a decrease in head thrashes and pharyngeal pumps frequency (P < 0.01). E2-a treatment resulted in a significantly lower brood size (P < 0.01). Additional E2-a treatment induced a significantly shortened lifespan, compared with the control (P < 0.05). These findings indicated that water-soluble fraction E2-a from S. moorcroftiana seeds was a potential helminthic agent.

Intestinal parasites from the 2nd-5th century AD latrine in the Roman Baths at Sagalassos (Turkey).

The aim of this research was to determine the species of intestinal parasite present in a Roman Imperial period population in Asia Minor, and to use this information to improve our understanding of health in the eastern Mediterranean region in Roman times. We analyzed five samples from the latrines of the Roman bath complex at Sagalassos, Turkey. Fecal biomarker analysis using 5ß-stanols has indicated the feces were of human origin. The eggs of roundworm (Ascaris) were identified in all five samples using microscopy, and the cysts of the protozoan Giardia duodenalis (which causes dysentery) were identified multiple times in one sample using ELISA. The positive G. duodenalis result at Sagalassos is particularly important as it represents the earliest reliable evidence for this parasite in the Old World (i.e. outside the Americas). As both these species of parasite are spread through the contamination of food and water by fecal material, their presence implies that Roman sanitation technologies such as latrines and public baths did not break the cycle of reinfection in this population. We then discuss the evidence for roundworm in the writings of the Roman physician Galen, who came from Pergamon, another town in western Asia Minor.

[Helminthology according to the philosophy of science of Imre Lakatos]. / La helmintología según la filosofía de la ciencia de Imre Lakatos.

Lakatos's philosophy of science has been used for different branches of biology, however this has not been true for helminthology. Therefore, this article examines the possibility of using his methodology of scientific research programmes (SRP) for reconstructing the history of the discipline of helminthology. It is upheld that the first SRP in biology was inaugurated by Aristotle, and its protective belt included a small group of auxiliary hypotheses referring to helminths. This programme continued up until the 17th century, when two rival programmes in helminthology arose: the internalist and the externalist. After the second half of the 19th century the internalist SRP was abandoned, while the externalist considerably broadened its protective belt during the 20th century. The internalist programme was abandoned due to the crucial experiments of Küchenmeister, which permitted the consolidation of the externalist SRP.

La helmintología según la filosofía de la ciencia de Imre Lakatos / Helminthology according to the philosophy of science of Imre Lakatos

RESUMEN A pesar de que en distintas ramas de la biología se ha utilizado la filosofía de la ciencia de Lakatos, no se ha hecho esto con la helmintología. Aquí utilizamos su metodología de programas de investigación científica (PIC) para reconstruir la historia de la disciplina en cuestión. Sostenemos que el primer PIC de la biología lo inauguró Aristóteles, y en su cinturón protector hay un pequeño grupo de hipótesis auxiliares que se refieren a los helmintos. Ese programa se mantuvo vigente hasta el siglo XVII, época en la que surgen dos PIC rivales en helmintología: el internalista y el externalista. A partir de la segunda mitad del siglo XIX, el PIC internalista fue abandonado, mientras que el externalista amplió considerablemente su cinturón protector durante el siglo XX. El abandono del PIC internalista se debió a los experimentos cruciales de Küchenmeister, que permitieron la consolidación del PIC externalista.

ABSTRACT Lakatos’s philosophy of science has been used for different branches of biology, however this has not been true for helminthology. Therefore, this article examines the possibility of using his methodology of scientific research programmes (SRP) for reconstructing the history of the discipline of helminthology. It is upheld that the first SRP in biology was inaugurated by Aristotle, and its protective belt included a small group of auxiliary hypotheses referring to helminths. This programme continued up until the 17th century, when two rival programmes in helminthology arose: the internalist and the externalist. After the second half of the 19th century the internalist SRP was abandoned, while the externalist considerably broadened its protective belt during the 20th century. The internalist programme was abandoned due to the crucial experiments of Küchenmeister, which permitted the consolidation of the externalist SRP.

In vivo antimalarial activity of synthetic hepcidin against Plasmodium berghei in mice / 中国天然药物

The present study was designed to investigate the antimalarial activity of synthetic hepcidin and its effect on cytokine secretion in mice infected with Plasmodium berghei. The mice were infected with P. berghei intravenously and treated with hepcidin according to 4-day suppression test and Rane's test. The serum levels of interleukins (IL-1β, IL-2, IL-6, IL-10, IL-12p70, and IL-17A), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) in the experimental mice were determined using a cytometric bead array (CBA) kit. The survival rate of the infected mice was also registered. Additionally, the serum iron, alanine transaminase (ALT), aspartate transaminase (AST), and total bilirubin (BIL) were detected to evaluate liver functions. Hepcidin exerted direct anti-malarial function in vivo and increased survival rate in a dose-dependent manner. In addition, the secretion of T helper cell type 1 (Th1), Th2, and Th17 cytokines, TNF-α, and IFN-γ were inhibited by hepcidin. In conclusion, our results demonstrated that synthetic hepcidin exerts in vivo antimalarial activity and possesses anti-inflammatory function, which provides a basis for future design of new derivatives with ideal anti-malarial activity.

Ancient Human Parasites in Ethnic Chinese Populations.

Whilst archaeological evidence for many aspects of life in ancient China is well studied, there has been much less interest in ancient infectious diseases, such as intestinal parasites in past Chinese populations. Here, we bring together evidence from mummies, ancient latrines, and pelvic soil from burials, dating from the Neolithic Period to the Qing Dynasty, in order to better understand the health of the past inhabitants of China and the diseases endemic in the region. Seven species of intestinal parasite have been identified, namely roundworm, whipworm, Chinese liver fluke, oriental schistosome, pinworm, Taenia sp. tapeworm, and the intestinal fluke Fasciolopsis buski. It was found that in the past, roundworm, whipworm, and Chinese liver fluke appear to have been much more common than the other species. While roundworm and whipworm remained common into the late 20th century, Chinese liver fluke seems to have undergone a marked decline in its prevalence over time. The iconic transport route known as the Silk Road has been shown to have acted as a vector for the transmission of ancient diseases, highlighted by the discovery of Chinese liver fluke in a 2,000 year-old relay station in northwest China, 1,500 km outside its endemic range.

Microfluidic platform for electrophysiological recordings from host-stage hookworm and Ascaris suum larvae: A new tool for anthelmintic research.

The screening of candidate compounds and natural products for anthelmintic activity is important for discovering new drugs against human and animal parasites. We previously validated in Caenorhabditis elegans a microfluidic device ('chip') that records non-invasively the tiny electrophysiological signals generated by rhythmic contraction (pumping) of the worm's pharynx. These electropharyngeograms (EPGs) are recorded simultaneously from multiple worms per chip, providing a medium-throughput readout of muscular and neural activity that is especially useful for compounds targeting neurotransmitter receptors and ion channels. Microfluidic technologies have transformed C. elegans research and the goal of the current study was to validate hookworm and Ascaris suum host-stage larvae in the microfluidic EPG platform. Ancylostoma ceylanicum and A. caninum infective L3s (iL3s) that had been activated in vitro generally produced erratic EPG activity under the conditions tested. In contrast, A. ceylanicum L4s recovered from hamsters exhibited robust, sustained EPG activity, consisting of three waveforms: (1) conventional pumps as seen in other nematodes; (2) rapid voltage deflections, associated with irregular contractions of the esophagus and openings of the esophogeal-intestinal valve (termed a 'flutter'); and (3) hybrid waveforms, which we classified as pumps. For data analysis, pumps and flutters were combined and termed EPG 'events.' EPG waveform identification and analysis were performed semi-automatically using custom-designed software. The neuromodulator serotonin (5-hydroxytryptamine; 5HT) increased EPG event frequency in A. ceylanicum L4s at an optimal concentration of 0.5 mM. The anthelmintic drug ivermectin (IVM) inhibited EPG activity in a concentration-dependent manner. EPGs from A. suum L3s recovered from pig lungs exhibited robust pharyngeal pumping in 1 mM 5HT, which was inhibited by IVM. These experiments validate the use of A. ceylanicum L4s and A. suum L3s with the microfluidic EPG platform, providing a new tool for screening anthelmintic candidates or investigating parasitic nematode feeding behavior.