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1.
Vet Parasitol Reg Stud Reports ; 52: 101050, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38880579

RESUMO

Species belonging to the family Paramphistomidae Fischoeder, 1901, commonly known as "rumen flukes", are a group of parasites frequently related to Brazilian livestock production. They inhabit the digestive tract of ruminants and have recognized pathogenicity during the early stages of infection, which can be responsible for economic losses. These trematodes are often associated with Southern Brazil, a region heavily focused on animal farming, which also makes it ideal for the life cycle of paramphistomes. Despite their aforementioned importance, studies regarding their distribution, molecular taxonomy and biology are still scarce in the country. In the present study, rumen flukes collected from cattle (n = 22) and sheep (n = 3) from 9 batches of ruminants from the cities of Jaguarão, Pelotas and Rio Grande, state of Rio Grande do Sul, Brazil, between May and July 2022, were subjected to morphological and molecular study. The microscopic analysis of histological and manual cuts revealed diagnostical traits compatible with Paramphistomum leydeni Näsmark, 1937, including the presence of tegumental papillae, pharynx of the liorchis type and acetabulum of the leydeni type. Molecular data corroborated the morphological identification, with ITS-2 and cox-1 sequences here obtained presenting 100% and 96.8-99.8% similarity, respectively, to P. leydeni samples previously characterized in different countries from Asia, Europe, and South America. Intensity of infection ranged from 5 to 458 and 1 to3 specimens of P. leydeni in sampled cattle and sheep, respectively. The present study contributes to a better understanding of the taxonomy of the flukes involved in cattle and sheep paramphistomosis in Brazil, suggesting that P. leydeni could be the main paramphistome species found in ruminants in the studied region.


Assuntos
Doenças dos Bovinos , Paramphistomatidae , Doenças dos Ovinos , Infecções por Trematódeos , Animais , Brasil/epidemiologia , Bovinos , Ovinos , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/epidemiologia , Paramphistomatidae/genética , Paramphistomatidae/classificação , Paramphistomatidae/isolamento & purificação , Rúmen/parasitologia , Filogenia
2.
Front Oral Health ; 5: 1359132, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38813461

RESUMO

Introduction: Patient and Public Involvement (PPI) can have a positive impact on research. PPI can make research more meaningful and appropriate as well as preventing research waste. For decades, patient advocates with HIV have played a key part in public health and research. This article presents the PPI activity undertaken during a doctoral study. The aim of this article is to demonstrate how PPI was embedded into a doctoral study that explored the feasibility of HIV testing in dental settings. Methods: Patients and the public were invited to be involved with the feasibility study through various organisations and charities. A comprehensive PPI activity strategy was devised, and appropriate funding was obtained. Patients and the public were predominantly consulted or collaboratively involved with several aspects of the study. Findings: Patients and the public positively contributed to the intervention development and the resources supporting its implementation. As a result, the study resources (i.e., questionnaire and information leaflets) were easier to read, and the intervention was more appropriate to the needs of patients. Furthermore, the training and focus groups conducted with dental patients and people with HIV benefitted from input of people with lived experience. Conclusions: PPI can be embedded within doctoral studies provided there is sufficient funding, flexibility, and supervisory support. However, PPI activity may be impacted by limited resource and a priori research protocol and funding agreements.

3.
Parasitol Int ; 100: 102867, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38364969

RESUMO

Despite the importance of fish-borne trematodes of the family Opisthorchiidae as causative agents of human liver fluke disease, studies on these parasites outside Asia are relativally scarce. In South America, human focus of amphimerosis is known in Ecuador since the mid-20th century, and Amphimerus spp. have also been reported in wild and domestic mammals. Nevertheless, the knowledge on the snails that act as the first intermediate host of these potentially zoonotic parasites are scarce. Herein, a new cercaria of the pleurolophocercous morphotype found in the freshwater snail Idiopyrgus souleyetianus from Brazil was subjected to morphological and molecular studies. Multigene phylogenetic analyses based on 28S, 5.8S-ITS-2 and Cox-1 sequences enabled the identification of Amphimerus sp., a species distinct from that reported in humans from Ecuador. This cercariae was morphologically compared with other opisthorchiid cercariae known. The possible occurrence of human amphimerosis in Brazil is discussed.


Assuntos
Fasciola hepatica , Opisthorchidae , Trematódeos , Infecções por Trematódeos , Animais , Humanos , Brasil , Filogenia , Caramujos/parasitologia , Cercárias/genética , Cercárias/anatomia & histologia , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , Mamíferos
4.
Science ; 383(6680): 293-297, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38236975

RESUMO

Plants sustain human life. Understanding geographic patterns of the diversity of species used by people is thus essential for the sustainable management of plant resources. Here, we investigate the global distribution of 35,687 utilized plant species spanning 10 use categories (e.g., food, medicine, material). Our findings indicate general concordance between utilized and total plant diversity, supporting the potential for simultaneously conserving species diversity and its contributions to people. Although Indigenous lands across Mesoamerica, the Horn of Africa, and Southern Asia harbor a disproportionate diversity of utilized plants, the incidence of protected areas is negatively correlated with utilized species richness. Finding mechanisms to preserve areas containing concentrations of utilized plants and traditional knowledge must become a priority for the implementation of the Kunming-Montreal Global Biodiversity Framework.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Dispersão Vegetal , Plantas , Humanos , África , Ecossistema , Alimentos , Conhecimento
5.
Nat Commun ; 14(1): 7083, 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37925495

RESUMO

Feedback oscillators, consisting of an amplifier whose output is partially fed back to its input, provide stable references for standardization and synchronization. Notably, the laser is such an oscillator whose performance can be limited by quantum fluctuations. The resulting frequency instability, quantified by the Schawlow-Townes formula, sets a limit to laser linewidth. Here, we show that the Schawlow-Townes formula applies universally to feedback oscillators beyond lasers. This is because it arises from quantum noise added by the amplifier and out-coupler in the feedback loop. Tracing the precise origin of quantum noise in an oscillator informs techniques to systematically evade it: we show how squeezing and entanglement can enable sub-Schawlow-Townes linewidth feedback oscillators. Our analysis clarifies the quantum limits to the stability of feedback oscillators in general, derives a standard quantum limit (SQL) for all such devices, and quantifies the efficacy of quantum strategies in realizing sub-SQL oscillators.

7.
Ann Parasitol ; 69(1): 31-36, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37768302

RESUMO

Non-parasitic vermiform organisms can circumstantially be associated with humans and their identification can be challenging for medical professionals. The present report describes the finding of a worm in the toilet bowl by a patient from Brazil, who thought he had expelled it in his feces. The gross analyses in a clinical laboratory reveal the worm was different from other macroscopic organisms routinely identified, and the laboratory staff requested assistance in an academic laboratory specialized in helminthology. After preliminary analysis in a stereomicroscope, the supposed human worm was identified as an oligochaete annelid (earthworm). The patient was contacted to investigate a possible case of pseudoparasitism. However, we were informed that the organism had been collected in a toilet bowl from a rural environment where the untreated water comes from a cistern indicating our finding was circumstantial. The methodology revisited herein allowed a quick microscopic analysis of easy-to-view morphological structures, which are useful to separate oligochaete annelids from helminths and can prevent misdiagnosis in similar situations. We discuss the overly restricted view on human parasites by health professionals in collecting clinical history and laboratory analysis, providing some epistemological insights on the necessary interdisciplinarity between parasitology and other basic knowledge with health practice.


Assuntos
Aparelho Sanitário , Parasitos , Masculino , Animais , Humanos , Brasil/epidemiologia , Fezes
9.
Trends Parasitol ; 39(9): 801-802, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37419860

Assuntos
Caramujos , Animais
10.
Small ; 19(31): e2300541, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37058095

RESUMO

Biodiesel remains one of the most promising alternatives to replace fossil fuel-derived petrodiesel. Nonetheless, conventional biodiesel synthesis relies on homogeneous alkali-based catalysts that involve long and tedious purification steps , increasing biodiesel production costs. Heterogeneous catalysts have emerged as promising alternatives to circumvent these drawbacks, as they can easily be recovered and reused. Herein, polymeric carbon nitride dots and nanosheets are synthesized through a solid-phase reaction between urea and sodium citrate. Their morphology and surface chemistry are tuned by varying the precursor's ratio, and the materials are investigated as catalysts in the transesterification reaction of canola oil to biodiesel. A conversion of > 98% is achieved using a 5 wt% catalyst loading, oil to methanol ratio of 1:36 at 90 °C for 4 h, with the performance maintained over at least five reuse cycles. In addition, the effect of the transesterification reaction parameters on the reaction kinetics is evaluated, which follows a pseudo-first-order (PFO) regime. Combined with a deep understanding of the catalyst's surface, these results have allowed us to propose a reaction mechanism similar to the one observed for homogenous alkali catalysts. These carbon nitride-based nanoparticles offer a metal-free and cost-effective alternative to conventional homogeneous and metal-based heterogeneous catalysts.

11.
Chem Commun (Camb) ; 59(21): 3071-3074, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36753325

RESUMO

A Zr6-based metal-organic framework (MOF), MOF-808, is investigated for the adsorptive removal of IO3- from aqueous solutions, due to its high surface area and abundance of open metal sites. The uptake kinetics, adsorption capacity and binding mode are studied, showing a maximum uptake capacity of 233 mg g-1, the highest reported by any material.

12.
Parasitology ; : 1-11, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36632020

RESUMO

Echinostoma paraensei, described in Brazil at the end of the 1960s and used as a biological model for a range of studies, belongs to the 'revolutum' complex of Echinostoma comprising species with 37 collar spines. However, molecular data are available only for a few isolates maintained under laboratory conditions, with molecular prospecting based on specimens originating from naturally infected hosts virtually lacking. The present study describes Echinostoma maldonadoi Valadão, Alves & Pinto n. sp., a species cryptically related to E. paraensei found in Brazil. Larval stages (cercariae, metacercariae and rediae) of the new species were found in the physid snail Stenophysa marmorata in the State of Minas Gerais, Brazil, the same geographical area where E. paraensei was originally described. Adult parasites obtained experimentally in Meriones unguiculatus were used for morphological (optical microscopy) and molecular [28S, internal transcribed spacer (ITS), nad1 and cox1] characterization. The morphology of larval and adult parasites (most notable the small-sized dorsal spines in the head collar), associated with low (0­0.1%) molecular divergence for 28S gene or ITS region, and only moderate divergence for the mitochondrial cox1 gene (3.83%), might suggest that the newly collected specimens should be assigned to E. paraensei. However, higher genetic divergence (6.16­6.39%) was found in the mitochondrial nad1, revealing that it is a genetically distinct, cryptic lineage. In the most informative phylogenetic reconstruction, based on nad1, E. maldonadoi n. sp. exhibited a strongly supported sister relationship with E. paraensei, which may indicate a very recent speciation event giving rise to these 2 species.

13.
Sci Total Environ ; 867: 161259, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638981

RESUMO

Constructed wetlands (CWs) have been demonstrated as a cost-effective alternative to chemical treatment systems for mine waters, with the microbial communities attributed to promoting carbonation and aiding pH neutralization. However, few data are available for the long-term use of CWs treating alkaline leachates nor the activity of microbes within them. To investigate the feasibility of CW to buffer alkaline pH, a pilot-scale wetland was implemented in 2015 to treat alkaline bauxite residue leachate. After 5.5 years, samples of supernatant water and sediment were taken at 0.5 m increments along the 11 m long wetland. Waters were analysed for pH, EC and metal(loid) content, while sediment was subjected to physico-chemical assessment and element fractionation. Microbial biomass and community were assessed by phospholipid fatty acid analysis (PLFA) and functionality by the Rapid Automated Bacterial Impedance Technique (RABIT). Evidence presented demonstrates that the CW operating for 66 months effectively treats bauxite residue leachate, with reduced influent pH from 11.5 to 7.8. Trace element analysis revealed effective reduction in Al (94.9 %), As (86.7 %) and V (57.6 %) with substrate analysis revealing a frontloading of elevated pH and trace element content in the first 5 m of the wetland. Sediment Al, As and V were present mostly (>94 % of total) in recalcitrant forms. Sediment Na was mostly soluble (48-62 %), but soils were not sodic (ESP < 15 %). Investigations into the microbial community revealed greatest biomass was in the first 5 m of the wetland, where pH, EC and metal contents were greatest. Microbial respiration using endemic Phragmites australis as a substrate demonstrates an ability to cycle recalcitrant carbon sources within a CW system. These novel microbial findings highlight the need for further investigation into the microbial communities in alkaline CWs.


Assuntos
Microbiota , Oligoelementos , Áreas Alagadas , Metais/química , Óxido de Alumínio/química
14.
Acta Parasitol ; 68(1): 282-287, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36705769

RESUMO

PURPOSE: Eucotylid trematodes are parasites of the urinary system of birds with a cosmopolitan distribution. Despite the importance of these flukes, fundamental aspects of their biology, such as intermediate hosts and larval morphology, are poorly known. Herein, the potential involvement of aquatic mollusks in the transmission of a species of Tanaisia is reported for the first time. METHODS: During the search of non-emergent larval stages of trematodes in mollusks collected from an urban waterbody from Brazil in February of 2021, 1 out of 18 specimens (5.5%) of Biomphalaria straminea was found harboring sporocysts, cercariae and encysted metacercariae morphologically compatible with those described for eucotylid species. Sequences generated for 28S, ITS-2, and cox1 molecular markers were compared with sequences available in GenBank and subjected to phylogenetic analyses. RESULTS: Molecular analyses revealed parasite affiliation with members of the genus Tanaisia, given it groped in a strongly supported clade with species of this genus included in the 28S phylogenetic tree. The larvae tentatively identified as Tanaisia sp. can be conspecific with an unpublished isolate of Tanaisia valida found in birds in South Brazil (100% similarity in 28S and ITS-2). CONCLUSION: Biomphalaria straminea is reported as a natural host of a species of Tanaisia for the first time. This finding highlights the possibility, so far unknown, of transmission of species of the family Eucotylidae in aquatic environments.


Assuntos
Biomphalaria , Trematódeos , Animais , Biomphalaria/parasitologia , Brasil , Filogenia , Aves
15.
Pathogens ; 11(12)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36558867

RESUMO

The present work aimed to study ecological aspects related to the distribution pattern of medically important and native freshwater mollusks, found in a rural municipality in the state of Minas Gerais, Brazil. Malacological captures were carried out in aquatic environments (lentic and lotic) from 46 locations between October 2018 and September 2019. The collected specimens were subjected to taxonomic identification and evaluation for infection with trematode larvae. Qualitative data were used to analyze the similarity and the odds ratios between the environmental variables. In total, 1125 specimens were sampled, belonging to the following species: Biomphalaria glabrata, B. tenagophila, B. straminea, B. kuhniana, B. cousini, Biomphalaria sp., and Drepanotrema cimex (Planorbidae), Stenophysa marmorata (Physidae), Omalonyx sp. (Succineidae), Pseudosuccinea columella (Lymnaeidae), and Pomacea sp. (Ampullaridae). Echinostome, strigeocercaria, and xiphidiocercaria types of larval trematodes were detected in S. marmorata and D. cimex. Of note was the similarity in the distribution of S. marmorata, a supposedly endangered species, with that of the medically important Biomphalaria species, with the two sharing environments. This complex scenario led us to reflect on and discuss the need for the control of important intermediate hosts, as well as the conservation of endangered species. This relevant issue has not yet been discussed in detail, in Brazil or in other countries that recommend snail control.

16.
Chem Commun (Camb) ; 58(78): 10925-10928, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36065793

RESUMO

Y-CU-45, an analogue of Zr-MOF-808, is synthesized for the first time. Several reaction conditions are tested demonstrating that two fluorinated modulators are required for a reproducible synthesis yielding high quality material. Y-CU-45 shows high crystallinity and surface area, shining light on the potential for rare-earth cluster-based MOFs with open metal sites.

17.
Int J Parasitol Parasites Wildl ; 19: 84-88, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36090667

RESUMO

Despite the recent advances raised in the molecular era to the taxonomic knowledge of species of the family Clinostomidae, especially those belonging to the specious genus Clinostomum, some groups of these vertebrate parasites remain poorly studied. This is the case of species of the enigmatic genus Ithyoclinostomum Witenberg, 1926, until recently monotypic and restricted to South America, but with its occurrence expanded to North America after the description of I. yamagutii Rosser et al., 2020. Nevertheless, molecular data for the type species of the genus, Ithyoclinostomum dimorphum (Diesing, 1850), is lacking so far. In the present study, large clinostomid metacercariae morphologically indistinguishable from I. dimorphum were obtained from two erythrinid fishes from the Rio Doce River, Southeast Brazil. Samples of the parasites were subjected to a multigene (28S rDNA, ITS and cox1) molecular characterization followed by phylogenetic reconstructions. Phylogenies based on single-gene and concatenated datasets revealed unequivocally that I. dimorphum falls in a well-supported clade together with species of the genus Clinostomum. Moreover, the molecular divergences observed in relation to Clinostomum spp. [ranges of 2.4-6%, 2.4-3.8% and 14.7-19.3% for the ITS, 28S and cox1 genes, respectively] are compatible with a congeneric status with these species. Therefore, the genus Ithyoclinostomum is here synonymized with Clinostomum Leidy, 1856 and C. dimorphum (Diesing, 1850) Braun, 1899 re-established. In the phylogenetic analysis, the recently described 'Ithyoclinostomum' yamagutii, presented as an isolated, independent lineage, showing significant molecular divergences to C. dimorphum (12.6%, 7.6%, 18,6% for the ITS, 28S and cox1 genes, respectively). However, given the complex scenario raised in the morphology-based taxonomy of Clinostomidae, we took a conservative approach by not proposing a new genus to 'I.' yamagutii until molecular data of other clinostomid genus from birds, Clinostomatopsis, become available. Data here presented reveals that body size is not a useful criterion for higher-level classification in Clinostomidae. Finally, we highlighted the importance of the availability of molecular data for the type species of trematode genera proposed from South America to support a trans- or intercontinental distribution.

18.
Pathogens ; 11(7)2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35890014

RESUMO

Schistosomatidae Stiles and Hassall 1898 is a medically significant family of digenetic trematodes (Trematoda: Digenea), members of which infect mammals or birds as definitive hosts and aquatic or amphibious gastropods as intermediate hosts. Currently, there are 17 named genera, for many of which evolutionary interrelationships remain unresolved. The lack of a resolved phylogeny has encumbered our understanding of schistosomatid evolution, specifically patterns of host-use and the role of host-switching in diversification. Here, we used targeted sequence capture of ultra-conserved elements (UCEs) from representatives of 13 of the 17 named genera and 11 undescribed lineages that are presumed to represent either novel genera or species to generate a phylogenomic dataset for the estimation of schistosomatid interrelationships. This study represents the largest phylogenetic effort within the Schistosomatidae in both the number of loci and breadth of taxon sampling. We present a near-comprehensive family-level phylogeny providing resolution to several clades of long-standing uncertainty within Schistosomatidae, including resolution for the placement of the North American mammalian schistosomes, implying a second separate capture of mammalian hosts. Additionally, we present evidence for the placement of Macrobilharzia at the base of the Schistosoma + Bivitellobilharzia radiation. Patterns of definitive and intermediate host use and a strong role for intermediate host-switching are discussed relative to schistosomatid diversification.

19.
Parasitol Int ; 90: 102607, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35659634

RESUMO

Human cercarial dermatitis (HCD) caused by avian schistosomes is an emerging health issue in different parts of the world. Nevertheless, parasite diversity, life cycle, and involvement in HCD remain poorly known or neglected in South America. Herein, we reported data obtained during a long-term malacological survey carried out in Pampulha Reservoir, an urban eutrophic waterbody from Brazil between 2009 and 2012. An ocellate brevifurcate cercaria emerged from 55 of 16,235 (0.34%) specimens of Biomphalaria straminea. Samples of the cercariae were subjected to morphological, experimental, and molecular study (analysis of partial sequences of nuclear 28S and mitochondrial cox1 genes). The molecular analysis revealed that the larva corresponds to an avian schistosome; however, it does not correspond to any named genus. A close related isolate was previously reported in Biomphalaria sudanica from Kenya (molecular divergences of 0.54% and 9.62% for 28S and cox1, respectively). The morphology of this cercaria was compared with other avian schistosome larvae from Biomphalaria spp. Attempts to infect experimentally ducks (Cairina moschata) and mice revealed cutaneous manifestations after exposure to cercariae, but adult parasites were not obtained in these hosts. Phylogenetic analysis suggests this parasite is a putative new genus and species of avian schistosome. The potential involvement of the larvae herein described in cases of HCD in Brazil cannot be ruled out. Surprisingly, HCD was not reported in the country so far, which can be related to difficulties in its diagnosis in areas of overlap with human schistosomes.


Assuntos
Biomphalaria , Dermatite , Esquistossomose , Dermatopatias Parasitárias , Trematódeos , Animais , Biomphalaria/parasitologia , Brasil/epidemiologia , Cercárias/anatomia & histologia , Patos , Humanos , Camundongos , Filogenia , Esquistossomose/epidemiologia , Esquistossomose/parasitologia , Esquistossomose/veterinária , Caramujos
20.
Vet Parasitol Reg Stud Reports ; 31: 100726, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35569908

RESUMO

Platynosomum illiciens is a dicrocoeliid trematode from the biliary tract of warm-blooded vertebrates (felines, primates, marsupials, and birds) reported in different parts of the world. Although the veterinary relevance of platynosomosis in mammals, especially in domestic felines, has been increasingly evidenced in the scientific literature, studies involving avian disease caused by P. illiciens are comparatively scarce. In the present study, a female specimen of the American kestrel, Falco sparverius L., found dead, in November 2019, in Brazil, was necropsied. Parietal biliary effusion in the celomatic cavity was observed, suggesting biliary transudation and gallbladder stasis, which possibily preceded the distension and rupture of gallbladder noted during necropsy. In the microscopic analysis of the bile content, small trematodes were found and characterized as immature stages of Platynosomum after the morphological study. Partial sequences of the cox-1 gene enabled the identification of P. illiciens, with 100% similarity with previously sequenced sympatric isolates from mammals. The finding of immature specimens in a ruptured gallbladder strongly suggests a role for the parasite in biliary flow dysfunction, indicating acute platynosomosis as a clinically relevant and potentially fatal condition that has not yet been discussed.


Assuntos
Dicrocoeliidae , Falconiformes , Infecções por Trematódeos , Animais , Brasil/epidemiologia , Dicrocoeliidae/genética , Falconiformes/parasitologia , Feminino , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária
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