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Introduction. El Alférez, a village in Los Montes de María (Bolívar, Colombia) and a macro-focus of leishmaniasis, recorded its first case in 2018, evidencing changes in the distribution and eco-epidemiology of the disease, although interactions between vectors and local fauna remain unknown. Objective. To evaluate the diversity of sandflies and their blood meal sources in the community of El Alférez in the municipality of El Carmen de Bolívar (Bolívar, Colombia). Materials and methods. In 2018, sandflies were collected using LED-based light traps in domestic, peridomestic, and sylvatic ecotopes and identified at the species level. Multiplex polymerase chain reaction targeting the mitochondrial cytochrome B gene was used to analyze blood from the digestive tract. Results. Lutzomyia evansi was the most abundant species (71.85%; n = 485/675), followed by Lu. panamensis, Lu. gomezi, Lu. trinidadensis, Lu. dubitans, Lu. abonnenci, and Lu.aclydifera. Twenty-five percent of the species had blood meals from Canis familiaris (36.00%; n = 9/25), Ovis aries (36.00%; n=9:/25), Bos taurus (24.00%; n = 6/25), Sus scrofa (20.00%; n = 5/25), and Homo sapiens (8.00%; n = 2/25). Lutzomyia evansi registered the highest feeding frequency (68.00%; n = 17/25), predominantly on a single (44.00%; n = 11/25) or multiple species (24.00%; n = 6/25). Conclusion. Results indicate a eclectic feeding behavior in Lu. evansi, implying potential reservoir hosts for Leishmania spp. and increasing transmission risk. This study is a first step towards understanding the diversity of mammalian blood sources used by sandflies, that may be crucial for vector identification and formulation of effective control measures.

Introducción. En 2018, en la vereda El Alférez de Los Montes de María (Bolívar, Colombia), un macrofoco de leishmaniasis, se reportó el primer caso y se evidenciaron cambios en la distribución y ecoepidemiología de la enfermedad. No obstante, las interacciones entre vectores y fauna local aún son desconocidas. Objetivo. Evaluar la diversidad de flebotomíneos y sus fuentes de alimentación sanguínea en la comunidad de El Alférez del municipio de El Carmen de Bolívar (Bolívar, Colombia). Materiales y métodos. En el 2018, se recolectaron flebotomíneos mediante trampas de luz led ubicadas en el domicilio, el peridomicilio y en el área silvestre, y se identificaron a nivel de especie. Se utilizó la reacción en cadena de la polimerasa múltiple dirigida al gen mitocondrial citocromo B para analizar la sangre del aparato digestivo. Resultados. Lutzomyia evansi fue la especie más abundante (71,85 %; n = 485/675), seguida por Lu. panamensis, Lu. gomezi, Lu. trinidadensis, Lu. dubitans, Lu. abonnenci y Lu. aclydifera. El 25 % (n = 25/100) de las especies analizadas tuvieron como fuentes de ingesta sanguínea a Canis familiaris (36 %; n = 9/25), Ovis aries (36 %; n = 9/25), Bos taurus (24 %; n = 6/25), Sus scrofa (20 %; n = 5/25) y Homo sapiens (8 %; n = 2/25). Lutzomyia evansi fue la especie con la mayor frecuencia de alimentación (68 %; n = 17/25), predominantemente de una sola especie (44 %; n = 11/25) o de varias (24 %; n = 6/25).

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Using integrative tools can be effective for species identification, especially in complex groups like Astyanax. Astyanax bimaculatus group is composed of six valid species, including A. lacustris. "A. altiparanae", "A. asuncionensis", and "A. jacuhiensis" are considered as junior synonyms of A. lacustris. Seeking to test the operational taxonomic unit (OTU) status of the junior synonyms of A. lacustris ("A. altiparanae", "A. asuncionensis", and "A. jacuhiensis"), we used analyses through mitochondrial DNA (COI and Cytb), cytogenetic markers (classical and molecular), and morphometry ("truss network"). Analysis of mitochondrial DNA sequences separated A. lacustris from the other synonymized species. The cytogenetic and morphometric analyses did not corroborate the synonymization and suggest that besides A. lacustris, the OTUs A. altiparanae, A. asuncionensis, and A. jacuhiensis are valid species. The analysis of different characters proposed by the integrative taxonomy used on the same individuals could provide greater reliability and minimize the underestimation of biodiversity.

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Molecular appraoch for identification of unknown species by using Cytochrome b gene is an effective and reliable as compared with morphological based identification. For DNA barcoding universal molecular genes were used to identify the species. Cytochrome b is a specific gene used for identification purpose. DNA barcoding is a reliable and effective method compared to the different traditional morphological methods of specie identification. So,in the present study which was conducted to identify the species, a total of 50 fish samples were collected from five different sites. DNA was extracted by using the Phenol Chloroform method from muscle tissue. Five sequences were sequenced (one from each site), analyzed, and identified specific species as Pangasius pangasius. Identified sequences were variable in length from 369 bp (Site 1), 364 bp (Site 2), 364 bp (Site 3), 352 bp (Site 4), and 334 bp (Site 5). Identity matches on the NCBI database confirmed the specific specie as P. pangasius. A distancing tree was drawn to show maximum likelihood among the same and different species. Yet, in many cases fishes on diverse development stages are difficult to identify by morphological characters. DNA-based identification methods offer an analytically powerful addition or even an alternative tool for species identification and phylogenetic study. This work intends to provide an updated and extensive overview on the DNA based methods for fish species identification by using Cytochrome b gene as targeted markers for identification purpose.

A abordagem molecular para identificação de espécies desconhecidas usando o gene citocromo b é eficaz e confiável em comparação com a identificação baseada na morfologia. Códigos de barras de DNA de genes moleculares universais foram usados ​​para identificar as espécies. O citocromo b é um gene específico usado para fins de identificação. O código de barras de DNA é um método confiável e eficaz em comparação com os diferentes métodos morfológicos tradicionais de identificação de espécies. Assim, no presente estudo, que foi realizado para identificar as espécies, um total de 50 amostras de peixes foram coletadas em cinco locais diferentes. O DNA foi extraído usando o método Fenol Clorofórmio do tecido muscular. Cinco sequências foram sequenciadas (uma de cada local), analisadas e identificadas espécies específicas, como Pangasius pangasius. As sequências identificadas tinham comprimento variável de 369 bp (Local 1), 364 bp (Local 2), 369 bp (Local 1), 364 bp (Local 3), 352 bp (Local 4) e 334 bp (Local 5). As correspondências de identidade no banco de dados do NCBI confirmaram a espécie específica como P. pangasius. Uma árvore de distanciamento foi desenhada para mostrar a máxima probabilidade entre elas e diferentes espécies. No entanto, em muitos casos, peixes em diversos estágios de desenvolvimento são difíceis de identificar por caracteres morfológicos. Os métodos de identificação baseados em DNA oferecem uma adição analiticamente poderosa ou mesmo uma ferramenta alternativa para identificação de espécies e estudo filogenético. Este trabalho pretende fornecer uma visão geral atualizada e abrangente sobre os métodos baseados em DNA para identificação de espécies de peixes usando o gene citocromo b como marcadores direcionados para fins de identificação.

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Amyloid ß (Aß) oligomers are the most neurotoxic forms of Aß, and Aß(1-42) is the prevalent Aß peptide found in the amyloid plaques of Alzheimer's disease patients. Aß(25-35) is the shortest peptide that retains the toxicity of Aß(1-42). Aß oligomers bind to calmodulin (CaM) and calbindin-D28k with dissociation constants in the nanomolar Aß(1-42) concentration range. Aß and histidine-rich proteins have a high affinity for transition metal ions Cu2+, Fe3+ and Zn2+. In this work, we show that the fluorescence of Aß(1-42) HiLyteTM-Fluor555 can be used to monitor hexa-histidine peptide (His6) interaction with Aß(1-42). The formation of His6/Aß(1-42) complexes is also supported by docking results yielded by the MDockPeP Server. Also, we found that micromolar concentrations of His6 block the increase in the fluorescence of Aß(1-42) HiLyteTM-Fluor555 produced by its interaction with the proteins CaM and calbindin-D28k. In addition, we found that the His6-tag provides a high-affinity site for the binding of Aß(1-42) and Aß(25-35) peptides to the human recombinant cytochrome b5 reductase, and sensitizes this enzyme to inhibition by these peptides. In conclusion, our results suggest that a His6-tag could provide a valuable new tool to experimentally direct the action of neurotoxic Aß peptides toward selected cellular targets.

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The New World porcupines of the genus Coendou comprise 16 species of arboreal nocturnal rodents. Some of these species are poorly known and have not been included in phylogenetic analyses. Based on recently collected specimens with associated tissue from the Brazilian Amazonia, we investigate the distribution and phylogenetic relationships of Roosmalens' dwarf porcupine, Coendouroosmalenorum, using an integrative approach using mitochondrial gene sequences and morphological data from new specimens and localities. Our results recovered C.roosmalenorum in the subgenus Caaporamys. However, analyses of our molecular and combined datasets produced different topologies. The new record shows the presence of C.roosmalenorum 480 km to the southeast of the Rio Madeira and 95 km away from Rio Juruena in Mato Grosso state, indicating a wider distribution in southern Amazonia than suspected. All known records of C.roosmalenorum are in the Madeira biogeographical province, to which it might be endemic.

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Leishmaniasis is a dynamic disease in which transmission conditions change due to environmental and human behavioral factors. Epidemiological analyses have shown modifications in the spread profile and growing urbanization of the disease, justifying the expansion of endemic areas and increasing number of cases in dogs and humans. In the city of Belo Horizonte, located in the southeastern state of Minas Gerais (Brazil), visceral leishmaniasis (VL) is endemic, with a typical urban transmission pattern, but with different regional prevalence. This study was conducted at the Zoo of the Foundation of Municipal Parks and Zoobotany of Belo Horizonte (FPMZB-BH), located in the Pampulha region, which is among the areas most severely affected by VL. This study aimed to determine the taxonomic diversity of native phlebotomine sand flies (Diptera: Psychodidae), identify climatic variables that potentially affect the phenology of these insects, and determine the blood meal sources for female phlebotomine sand flies. To achieve this, 10 mammal enclosures in the zoo were selected using the presence of possible leishmaniasis reservoirs as a selection criterion, and sampled using light traps between August 2019 and August 2021. A total of 6034 phlebotomine sand flies were collected, indicating nine species, with Lutzomyia longipalpis being the very abundant species (65.35% of the total). Of the 108 engorged phlebotomine collected females, seven samples (6.5%) were positive for blood meals from humans, marsupials, canids, and birds. Relative humidity and rainfall increased the phenology of phlebotomine sand flies, with population increases in the hottest and wettest months. The data obtained will provide guidelines for competent health agencies to implement vector control measures to reduce the risk of leishmaniasis transmission in the FPMZB-BH.

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BACKGROUND: Angiostrongylus cantonensis (rat lungworm) is the main pathogen responsible for eosinophilic meningitis in humans. One of its intermediate snail hosts, Achatina fulica, was already present in many countries around the world before it appeared in the West Indies in the late 1980s. In the French territories in the Caribbean and northern South America, the first cases of human neuroangiostrongyliasis were reported in Martinique, Guadeloupe and French Guiana in 2002, 2013 and 2017, respectively. In order to better characterize angiostrongyliasis in Guadeloupe, particularly its geographical origin and route of introduction, we undertook molecular characterization of adult worms of Angiostrongylus cantonensis and its intermediate host Achatina fulica. METHODS: Genomic DNA of adult Angiostrongylus cantonensis and Achatina fulica was extracted and amplified by polymerase chain reaction (PCR) targeting the mitochondrial genes cytochrome B and C for A. cantonensis and 16S ribosomal RNA for A. fulica. The PCR products were sequenced and studied by phylogenetic analysis. RESULTS: Cytochrome B and cytochrome C molecular markers indicate a monophyletic lineage of A. cantonensis adult worms in Guadeloupe. Two sequences of A. fulica were identified. CONCLUSIONS: These results confirm the recent introduction of both Angiostrongylus cantonensis and Achatina fulica into Guadeloupe. Achatina fulica in Guadeloupe shares a common origin with those in Barbados and New Caledonia, while Angiostrongylus cantonensis in Guadeloupe shares a common origin with those in Brazil, Hawaii and Japan.

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Until now, Molossus melini was known only from its type locality, in the south of Santa Fe province, Argentina. Specimens of this species were collected in 2021 from a roost in a Fraxinus tree of the urban woodland of Paraná city, Entre Ríos province, Argentina. Bat identification was made by comparing external and cranial characters and measurements with those reported in the bibliography and corroborated by a phylogenetic analysis based on the cytochrome b gene. Also, multivariate morphometric analyses showed that cranial measurements, but not external ones, are informative enough to discriminate M. melini from the other Molossus species in Argentina (M. currentium, M. fluminensis, and M. molossus). This new record extends the distribution of M. melini from the south of Santa Fe province by 230 km to the northeast and represents the first record of the species in the Espinal ecoregion. Supplementary information: The online version contains supplementary material available at 10.1007/s13364-023-00679-1.

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Dibothriocephalus latus and Dibothriocephalus dendriticus are found throughout the temperate and sub-arctic zones of the northern hemisphere, but they are also found in the southern core countries of South America, Chile and Argentina. Genetic characteristics of D. latus and D. dendriticus from South America have yet to be fully defined. The present study aimed to understand the genetic characteristics of D. latus and D. dendriticus from Chile by haplotype network analysis of mitochondrial cytochrome c oxidase subunit I gene (cox1) and cytochrome b gene (cob), as well as their origins. Dibothriocephalus latus and D. dendriticus plerocercoid larvae were obtained from feral and/or wild salmonids captured in Lake Llanquihue in Región de Los Lagos, and Lake Panguipulli in Región de Los Ríos, located south of central Chile. Haplotype analysis of D. latus revealed that H1 in cox1 and H2 in cob are the key haplotypes common to D. latus across the world, including Chile, and both genes exhibited limited genetic diversity in D. latus. It was assumed that D. latus was brought into South America by European and Russian immigrants in the 19th century as previously reported. In contrast, both the cox1 and cob of D. dendriticus display considerable genetic diversity, with no common haplotypes between D. dendriticus populations from Chile and the northern hemisphere. More intriguingly, two cob haplotypes (H24, H25) detected in Chilean D. dendriticus were closely linked to haplotypes (H30, H31) detected in North American D. dendriticus, strongly implying that D. dendriticus in Chile was brought by piscivorous migrating birds from North America. It has also been estimated that the D. dendriticus from Chile genetically diverged from the D. dendriticus from the northern hemisphere approximately 1.11 million years ago, long before humans migrated to the southern parts of South America.

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Although molecular information for the wood stork (Mycteria americana) has been well described, data concerning their karyotypical organization and phylogenetic relationships with other storks are still scarce. Thus, we aimed to analyze the chromosomal organization and diversification of M. americana, and provide evolutionary insights based on phylogenetic data of Ciconiidae. For this, we applied both classical and molecular cytogenetic techniques to define the pattern of distribution of heterochromatic blocks and their chromosomal homology with Gallus gallus (GGA). Maximum likelihood analyses and Bayesian inferences (680 bp COI and 1007 bp Cytb genes) were used to determine their phylogenetic relationship with other storks. The results confirmed 2n = 72, and the heterochromatin distribution pattern was restricted to centromeric regions of the chromosomes. FISH experiments identified fusion and fission events involving chromosomes homologous to GGA macrochromosome pairs, some of which were previously found in other species of Ciconiidae, possibly corresponding to synapomorphies for the group. Phylogenetic analyses resulted in a tree that recovered only Ciconinii as a monophyletic group, while Mycteriini and Leptoptlini tribes were configured as paraphyletic clades. In addition, the association between phylogenetic and cytogenetic data corroborates the hypothesis of a reduction in the diploid number throughout the evolution of Ciconiidae.

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