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1.
Mol Biol Evol ; 39(4)2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35302613

RESUMO

Cryptosporidiosis is a major global health problem and a primary cause of diarrhea, particularly in young children in low- and middle-income countries (LMICs). The zoonotic Cryptosporidium parvum and anthroponotic Cryptosporidium hominis cause most human infections. Here, we present a comprehensive whole-genome study of C. hominis, comprising 114 isolates from 16 countries within five continents. We detect two lineages with distinct biology and demography, which diverged circa 500 years ago. We consider these lineages two subspecies and propose the names C. hominis hominis and C. hominis aquapotentis (gp60 subtype IbA10G2). In our study, C. h. hominis is almost exclusively represented by isolates from LMICs in Africa and Asia and appears to have undergone recent population contraction. In contrast, C. h. aquapotentis was found in high-income countries, mainly in Europe, North America, and Oceania, and appears to be expanding. Notably, C. h. aquapotentis is associated with high rates of direct human-to-human transmission, which may explain its success in countries with well-developed environmental sanitation infrastructure. Intriguingly, we detected genomic regions of introgression following secondary contact between the subspecies. This resulted in high diversity and divergence in genomic islands of putative virulence genes, including muc5 (CHUDEA2_430) and a hypothetical protein (CHUDEA6_5270). This diversity is maintained by balancing selection, suggesting a co-evolutionary arms race with the host. Finally, we find that recent gene flow from C. h. aquapotentis to C. h. hominis, likely associated with increased human migration, maybe driving the evolution of more virulent C. hominis variants.


Assuntos
Criptosporidiose , Cryptosporidium , Criança , Pré-Escolar , Criptosporidiose/epidemiologia , Criptosporidiose/genética , Cryptosporidium/genética , DNA de Protozoário/genética , Genoma , Genótipo , Humanos , Metagenômica
2.
Conserv Biol ; 36(4): e13918, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35554972

RESUMO

The pink pigeon (Nesoenas mayeri) is an endemic species of Mauritius that has made a remarkable recovery after a severe population bottleneck in the 1970s to early 1990s. Prior to this bottleneck, an ex situ population was established from which captive-bred individuals were released into free-living subpopulations to increase population size and genetic variation. This conservation rescue led to rapid population recovery to 400-480 individuals, and the species was twice downlisted on the International Union for the Conservation of Nature (IUCN) Red List. We analyzed the impacts of the bottleneck and genetic rescue on neutral genetic variation during and after population recovery (1993-2008) with restriction site-associated sequencing, microsatellite analyses, and quantitative genetic analysis of studbook data of 1112 birds from zoos in Europe and the United States. We used computer simulations to study the predicted changes in genetic variation and population viability from the past into the future. Genetic variation declined rapidly, despite the population rebound, and the effective population size was approximately an order of magnitude smaller than census size. The species carried a high genetic load of circa 15 lethal equivalents for longevity. Our computer simulations predicted continued inbreeding will likely result in increased expression of deleterious mutations (i.e., a high realized load) and severe inbreeding depression. Without continued conservation actions, it is likely that the pink pigeon will go extinct in the wild within 100 years. Conservation rescue of the pink pigeon has been instrumental in the recovery of the free-living population. However, further genetic rescue with captive-bred birds from zoos is required to recover lost variation, reduce expression of harmful deleterious variation, and prevent extinction. The use of genomics and modeling data can inform IUCN assessments of the viability and extinction risk of species, and it helps in assessments of the conservation dependency of populations.


La paloma rosada (Nesoenas mayeri) es una especie endémica de Mauricio que se ha recuperado impresionantemente después de un grave cuello de botella poblacional a principios de la década de 1970 que duró hasta inicios de la década de 1990. Antes de este cuello de botella se había establecido una población ex situ de la cual se liberaban individuos reproducidos en cautiverio a las subpoblaciones en libertad para incrementar la variación genética y el tamaño poblacional. Este rescate de conservación derivó en una recuperación rápida de la población (400-480 individuos) y la especie cambió positivamente de categoría dos veces en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN). Analizamos los impactos del cuello de botella y el rescate genético sobre la variación genética neutral durante y después de la recuperación poblacional (de 1993 a 2008) mediante secuenciación RAD, análisis de microsatélites y análisis genéticos cuantitativos de los datos del libro genealógico de 1112 aves ubicadas en zoológicos de Europa y los Estados Unidos. Usamos simulaciones por computadora para estudiar los cambios pronosticados en la variación genética y en la viabilidad poblacional del pasado hacia el futuro. La variación genética declinó rápidamente, a pesar de la recuperación poblacional, y el tamaño efectivo de la población fue aproximadamente un orden de magnitud más pequeño que el tamaño del censo. La especie contó con una carga genética elevada de casi 15 equivalentes letales para la longevidad. Nuestras simulaciones pronostican que la endogamia continua probablemente resultará en un incremento en la expresión de mutaciones deletéreas (es decir, una carga realizada elevada) y en una depresión endogámica severa. Sin acciones continuas para la conservación, es probable que la paloma rosada esté extinta en vida libre dentro de cien años. El rescate de conservación de la paloma rosada ha sido fundamental en la recuperación de la población silvestre; sin embargo, se requiere de un rescate genético adicional con las aves de reproducción en cautiverio de los zoológicos para recuperar la variación perdida, reducir la expresión de la variación deletérea dañina y prevenir la extinción. El uso de la genómica y los datos modelados puede orientar las valoraciones de la UICN sobre la viabilidad y el riesgo de extinción de las especies, además de que ayuda en la evaluación de la dependencia que tienen las poblaciones de la conservación.


Assuntos
Aves , Conservação dos Recursos Naturais , Animais , Aves/genética , Espécies em Perigo de Extinção , Europa (Continente) , Variação Genética , Genômica , Densidade Demográfica
3.
Parasitology ; 148(4): 408-419, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33261668

RESUMO

A prior systematic review on the efficacy of halofuginone (HFG) treatment to prevent or treat cryptosporidiosis in bovine calves was inconclusive. We undertook an updated synthesis and meta-analyses on key outcomes for the treatment of calves with HFG. Evaluated outcomes were oocyst shedding, diarrhoea, mortality and weight gain. Experiments had to describe results for same age animals in contemporary arms. Most doses were 100-150 mcg kg-1 day-1. Results were subgrouped by study design, experiments with the lowest risk of bias and lack of industry funding. Eighteen articles were found that described 25 experiments. Most evidence came from randomized controlled trials in Europe. Significantly lower incidence of oocyst shedding, diarrhoea burden and mortality was reported when treatment started before calves were 5 days old. Most studies reported on outcomes for animals up to at least 28 days old. Publication bias was possible in all outcomes and seemed especially likely for diarrhoea outcomes. Beneficial results when HFG treatment was initiated in calves older than 5 days were also found. Prophylactic treatment to prevent cryptosporidiosis is effective in preventing multiple negative outcomes and is beneficial to calf health and will result in a reduction of environmental contamination by Cryptosporidium oocysts.


Assuntos
Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/prevenção & controle , Coccidiostáticos/uso terapêutico , Criptosporidiose/tratamento farmacológico , Criptosporidiose/prevenção & controle , Piperidinas/uso terapêutico , Quinazolinonas/uso terapêutico , Animais , Bovinos , Doenças dos Bovinos/mortalidade , Doenças dos Bovinos/parasitologia , Coccidiostáticos/normas , Criptosporidiose/mortalidade , Cryptosporidium parvum/efeitos dos fármacos , Cryptosporidium parvum/fisiologia , Diarreia/veterinária , Fezes/parasitologia , Oocistos , Piperidinas/normas , Quinazolinonas/normas , Aumento de Peso
4.
Parasitology ; 148(10): 1125-1136, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33843511

RESUMO

Previously, it was suggested that haemadipsid leeches represent an important vector of trypanosomes amongst native animals in Australia. Consequently, Chtonobdella bilineata leeches were investigated for the presence of trypanosome species by polymerase chain reaction (PCR), DNA sequencing and in vitro isolation. Phylogenetic analysis ensued to further define the populations present. PCR targeting the 28S rDNA demonstrated that over 95% of C. bilineata contained trypanosomes; diversity profiling by deep amplicon sequencing of 18S rDNA indicated the presence of four different clusters related to the Trypanosoma (Megatrypanum) theileri. Novy­MacNeal­Nicolle slopes with liquid overlay were used to isolate trypanosomes into culture that proved similar in morphology to Trypanosoma cyclops in that they contained a large numbers of acidocalcisomes. Phylogeny of 18S rDNA/GAPDH/ND5 DNA sequences from primary cultures and subclones showed the trypanosomes were monophyletic, with T. cyclops as a sister group. Blood-meal analysis of leeches showed that leeches primarily contained blood from swamp wallaby (Wallabia bicolour), human (Homo sapiens) or horse (Equus sp.). The leech C. bilineata is a host for at least five lineages of Trypanosoma sp. and these are monophyletic with T. cyclops; we propose Trypanosoma cyclops australiensis as a subspecies of T. cyclops based on genetic similarity and biogeography considerations.


Assuntos
Interações Hospedeiro-Parasita , Sanguessugas/parasitologia , Trypanosoma/isolamento & purificação , Animais , DNA de Protozoário/análise , DNA Ribossômico/análise , New South Wales , Reação em Cadeia da Polimerase
5.
Parasitol Res ; 119(11): 3571-3584, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32996051

RESUMO

Cryptosporidiosis is common in young calves, causing diarrhoea, delayed growth, poor condition and excess mortality. No vaccine or cure exists, although symptomatic onset may be delayed with some chemoprophylactics. Other response and management strategies have focused on nutritional status, cleanliness and biosecurity. We undertook a systematic review of observational studies to identify risk or protective factors that could prevent Cryptosporidium parvum infection in calves. Included studies used multivariate analysis within cohort, cross-sectional or case-control designs, of risk factors among young calves, assessing C. parvum specifically. We tabulated data on characteristics and study quality and present narrative synthesis. Fourteen eligible studies were found; three of which were higher quality. The most consistent evidence suggested that risk of C. parvum infection increased when calves had more contact with other calves, were in larger herds or in organic production. Hard flooring reduced risk of infection and calves tended to have more cryptosporidiosis during warm and wet weather. While many other factors were not found to be associated with C. parvum infection, analyses were usually badly underpowered, due to clustering of management factors. Trials are needed to assess effects of manipulating calf contact, herd size, organic methods, hard flooring and temperature. Other factors need to be assessed in larger observational studies with improved disaggregation of potential risk factors.


Assuntos
Doenças dos Bovinos/prevenção & controle , Criptosporidiose/prevenção & controle , Cryptosporidium parvum , Animais , Bovinos , Estudos Transversais , Diarreia/veterinária , Fezes , Estudos Observacionais como Assunto , Fatores de Risco
6.
Microbiology (Reading) ; 165(5): 500-502, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31268415

RESUMO

The protozoan Cryptosporidium is notorious for its resistance to chlorine disinfection, a mainstay of water treatment. Human infections, mainly of the small intestine, arise from consumption of faecally contaminated food or water, environmental exposure, and person-to-person or animal-to-person spread. Acute gastrointestinal symptoms can be prolonged but are usually self-limiting. Problems arise with immune-deficient, including malnourished, people including chronic diarrhoea, hepato-biliary tree and extra-gastrointestinal site infection, and few options for treatment or prevention exist. Although genomics has enabled refined classification, identification of chemotherapeutic targets and vaccine candidates, and putative factors for host adaption and pathogenesis, their confirmation has been hampered by a lack of biological tools.


Assuntos
Criptosporidiose/microbiologia , Cryptosporidium/fisiologia , Animais , Cryptosporidium/classificação , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Genoma de Protozoário , Humanos , Filogenia
7.
Parasitology ; 145(12): 1548-1552, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29681249

RESUMO

Avian trichomonosis is an architypal disease of wild columbids and those birds that predate them. Increasingly though, it has been reported in passerines; a recent and ongoing epidemic in the chaffinches and greenfinches of Europe and outbreaks amongst house finches, American goldfinches and purple finches in North America. The parasite, Trichomonas gallinae, causes lesions in the upper respiratory tract which can cause mortality associated with dehydration and emaciation. This paper reports for the first time, the widespread, endemic and often asymptomatic infection of common mynah (Acridotheres tristis) around the Faisalabad District, Pakistan. Parasite typing was used to investigate the potential for transmission among the frequently sympatric species. Type C parasites were found in mynah, and while this is analagous to the pandemic finch strain which is Type A, it is the first known example of passerine infections of this parasite genotype. Subtype analysis showed the strain to be C4 a subtype which has a widespread distribution in columbids.


Assuntos
Doenças das Aves/epidemiologia , Tentilhões/parasitologia , Estorninhos/parasitologia , Tricomoníase/veterinária , Trichomonas/isolamento & purificação , Animais , Doenças das Aves/parasitologia , Epidemias/veterinária , Feminino , Genótipo , Masculino , Paquistão/epidemiologia , Filogenia , Trichomonas/genética , Tricomoníase/epidemiologia , Tricomoníase/parasitologia
8.
Traffic ; 14(7): 853-69, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23601193

RESUMO

Epithelial cell invasion by the protozoan parasite Trypanosoma cruzi is enhanced by the presence of an enzyme expressed on its cell surface during the trypomastigote life cycle stage. The enzyme, trans-sialidase (TS), is a member of one of the largest gene families expressed by the parasite and the role of its activity in mediating epithelial cell entry has not hitherto been understood. Here we show that the T. cruzi TS generates an eat me signal which is capable of enabling epithelial cell entry. We have utilized purified, recombinant, active (TcTS) and inactive (TcTS2V0) TS coated onto beads to challenge an epithelial cell line. We find that TS activity acts upon G protein coupled receptors present at the epithelial cell synapse with the coated bead, thereby enhancing cell entry. By so doing, we provide evidence that TS proteins bind glycans, mediate the formation of distinct synaptic domains and promote macropinocytotic uptake of microparticles into a perinuclear compartment in a manner which may emulate entosis.


Assuntos
Endocitose , Células Epiteliais/metabolismo , Glicoproteínas/metabolismo , Neuraminidase/metabolismo , Animais , Membrana Celular/metabolismo , Cães , Entose , Células Epiteliais/enzimologia , Células Epiteliais/fisiologia , Células Madin Darby de Rim Canino , Microesferas , Polissacarídeos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
9.
Parasitology ; 142(8): 1053-62, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25804862

RESUMO

Finch trichomonosis, caused by Trichomonas gallinae, emerged in the Canadian Maritime provinces in 2007 and has since caused ongoing mortality in regional purple finch (Carpodacus purpureus) and American goldfinch (Carduelis tristis) populations. Trichomonas gallinae was isolated from (1) finches and rock pigeons (Columbia livia) submitted for post-mortem or live-captured at bird feeding sites experiencing trichomonosis mortality; (2) bird seed at these same sites; and (3) rock pigeons live-captured at known roosts or humanely killed. Isolates were characterized using internal transcribed spacer (ITS) region and iron hydrogenase (Fe-hyd) gene sequences. Two distinct ITS types were found. Type A was identical to the UK finch epidemic strain and was isolated from finches and a rock pigeon with trichomonosis; apparently healthy rock pigeons and finches; and bird seed at an outbreak site. Type B was obtained from apparently healthy rock pigeons. Fe-hyd sequencing revealed six distinct subtypes. The predominant subtype in both finches and the rock pigeon with trichomonosis was identical to the UK finch epidemic strain A1. Single nucleotide polymorphisms in Fe-hyd sequences suggest there is fine-scale variation amongst isolates and that finch trichomonosis emergence in this region may not have been caused by a single spill-over event.


Assuntos
Doenças das Aves/epidemiologia , Columbidae/parasitologia , Epidemias , Tentilhões/parasitologia , Tricomoníase/veterinária , Trichomonas/genética , Animais , Sequência de Bases , Doenças das Aves/parasitologia , Canadá/epidemiologia , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Genótipo , Hidrogenase/genética , Proteínas Ferro-Enxofre/genética , Dados de Sequência Molecular , Filogenia , Proteínas de Protozoários/genética , Análise de Sequência de DNA/veterinária , Trichomonas/isolamento & purificação , Tricomoníase/epidemiologia , Tricomoníase/parasitologia
10.
Clin Microbiol Rev ; 26(1): 115-34, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23297262

RESUMO

Cryptosporidium is a protozoan parasite of medical and veterinary importance that causes gastroenteritis in a variety of vertebrate hosts. Several studies have reported different degrees of pathogenicity and virulence among Cryptosporidium species and isolates of the same species as well as evidence of variation in host susceptibility to infection. The identification and validation of Cryptosporidium virulence factors have been hindered by the renowned difficulties pertaining to the in vitro culture and genetic manipulation of this parasite. Nevertheless, substantial progress has been made in identifying putative virulence factors for Cryptosporidium. This progress has been accelerated since the publication of the Cryptosporidium parvum and C. hominis genomes, with the characterization of over 25 putative virulence factors identified by using a variety of immunological and molecular techniques and which are proposed to be involved in aspects of host-pathogen interactions from adhesion and locomotion to invasion and proliferation. Progress has also been made in the contribution of host factors that are associated with variations in both the severity and risk of infection. Here we provide a review comprised of the current state of knowledge on Cryptosporidium infectivity, pathogenesis, and transmissibility in light of our contemporary understanding of microbial virulence.


Assuntos
Criptosporidiose/patologia , Criptosporidiose/veterinária , Cryptosporidium/patogenicidade , Animais , Criptosporidiose/parasitologia , Criptosporidiose/transmissão , Cryptosporidium/genética , Cryptosporidium/crescimento & desenvolvimento , Gastroenterite/parasitologia , Gastroenterite/patologia , Gastroenterite/veterinária , Interações Hospedeiro-Patógeno , Humanos , Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
11.
J Clin Microbiol ; 52(4): 1081-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24452166

RESUMO

Vibrio parahaemolyticus is the leading bacterial cause of food-borne illness due to the consumption of contaminated seafood. The aim of the present study was to determine the population of its subtypes and establish a better understanding of the various types of V. parahaemolyticus strains that are causing human illness in Canada. The subtypes for 100 human clinical isolates of V. parahaemolyticus collected between 2000 and 2009 were determined by performing serotyping, ribotyping, pulsed-field gel electrophoresis, and multilocus sequence typing. Within this panel of strains, there was a high level of diversity (between 22 and 53 subtypes per method), but the presence of predominant clones with congruent subtypes between the various methods was also observed. For example, all 32 isolates belonging to sequence type 36 (ST36) were from serogroup O4, while 31 of them were ribotype EcoVib235-287, and 24 of the 32 were SfiI pulsed-field gel electrophoresis (PFGE) pattern VPSF1.0001. With regard to the presence of known virulence genes, 74 of the 100 isolates were PCR positive for the presence of the thermostable direct hemolysin (tdh); and 59 of these 74 strains also contained the second virulence marker, the tdh-related hemolysin (trh). The detection of trh was more predominant (81%) among the clinical isolates, and only four (4%) of the clinical isolates tested negative for the presence of both tdh and trh. This database, comprising 100 clinical isolates of V. parahaemolyticus strains from Canada, forms a baseline understanding of subtype diversity for future source attribution and other epidemiologic studies.


Assuntos
Tipagem Molecular , Sorotipagem , Vibrioses/microbiologia , Vibrio parahaemolyticus/classificação , Vibrio parahaemolyticus/isolamento & purificação , Canadá , Genótipo , Humanos , Fenótipo , Reação em Cadeia da Polimerase , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/fisiologia , Fatores de Virulência/genética
12.
Cell Microbiol ; 14(9): 1345-53, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22646288

RESUMO

It is widely accepted that Trypanosoma cruzi can exploit the natural exocytic response of the host to cell damage, utilizing host cell lysosomes as important effectors. It is, though, increasingly clear that the parasite also exploits endocytic mechanisms which allow for incorporation of plasma membrane into the parasitophorous vacuole. Further, that these endocytic mechanisms are involved in cross-talk with the exocytic machinery, in the recycling of vesicles and in the manipulation of the cytoskeleton. Here we review the mechanisms by which T. cruzi exploits features of the exocytic and endocytic pathways in epithelial and endothelial cells and the evidence for cross-talk between these pathways.


Assuntos
Endocitose , Exocitose , Interações Hospedeiro-Patógeno , Trypanosoma cruzi/patogenicidade , Vacúolos/parasitologia , Animais , Humanos , Modelos Biológicos
13.
Parasitology ; 140(10): 1234-45, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23920088

RESUMO

Avian trichomonosis, caused by the flagellated protozoan Trichomonas gallinae, is a recently emerged infectious disease of British passerines. The aetiological agent, a clonal epidemic strain of the parasite, has caused unprecedented finch mortality and population-level declines in Britain and has since spread to continental Europe. To better understand the potential origin of this epidemic and to further investigate its host range, T. gallinae DNA extracts were collected from parasite culture and tissue samples from a range of avian species in Britain. Sequence typing at the ITS1/5.8S rRNA/ITS2 region resolved three distinct ITS region types circulating in free-ranging British birds. Subtyping by sequence analyses at the Fe-hydrogenase gene demonstrated further strain variation within these ITS region types. The UK finch epidemic strain was preponderant amongst columbids sampled, however, wide strain diversity was encountered in isolates from a relatively small number of pigeons, suggesting further strains present in columbid populations across the UK are yet to be identified. Fe-hydrogenase gene sequence data in isolates from birds of prey with disease were predominantly identical to the UK finch epidemic strain, demonstrating its presence as a virulent strain in UK birds of prey since at least 2009.


Assuntos
Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Tentilhões/parasitologia , Tricomoníase/veterinária , Trichomonas/genética , Animais , DNA Espaçador Ribossômico/genética , Variação Genética , Especificidade de Hospedeiro , Hidrogenase/genética , Proteínas Ferro-Enxofre/genética , Dados de Sequência Molecular , Filogenia , Especificidade da Espécie , Trichomonas/classificação , Tricomoníase/epidemiologia , Tricomoníase/parasitologia , Reino Unido
14.
Cell Host Microbe ; 31(1): 5-7, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36634622

RESUMO

A new study in this issue of Cell Host & Microbe from Huang et al. provides important insights into the global epidemiology of human-infectious Cryptosporidium and mechanisms leading to the rapid emergence and rise to dominance of new, possibly more virulent, parasite strains.


Assuntos
Criptosporidiose , Cryptosporidium , Humanos , Cryptosporidium/genética , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia
15.
Virulence ; 14(1): 2273004, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37872759

RESUMO

Cryptosporidium spp. infection causes significant disease in immunosuppressed individuals and children under the age of 5 years. The severity of the pathological presentation of cryptosporidiosis is a function of the host and parasite genotypes, host immune status, and the enteric environment or microbiome of the host. Cryptosporidiosis often presents with abdominal pain and severe diarrhoea and is associated with intestinal dysbiosis and inflammation. Our systematic analysis of the available literature revealed that bacterial diversity is reduced during infection in larger animal models, lending support to recent studies which indicate that the use of probiotics or the presence of a naturally diverse gut microbiome can prevent or minimise pathology caused by gastrointestinal pathogens. In summary, we present evidence that the presence of a diverse gut microbiome, natural or induced, reduces both symptomatic pathology and oocyst output.


Assuntos
Criptosporidiose , Cryptosporidium parvum , Cryptosporidium , Microbioma Gastrointestinal , Animais , Criança , Humanos , Pré-Escolar , Criptosporidiose/parasitologia , Bactérias/genética , Fezes/parasitologia
16.
Biochim Biophys Acta ; 1808(3): 634-41, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21126508

RESUMO

Within the lateral organisation of plasma membranes of polarized cell types there exist heterogeneous microdomains of distinct lipid composition, the small size of which (10-200 nm) makes them difficult to discern with traditional microscopic techniques, but which can be distinguished on the basis of lipid packing. These microdomains or rafts can be concentrated in larger more visible liquid-ordered regions, particularly by cross-linking of their constituents as in the immunological synapse or in features of the polarized cell such as pseudopodia or flagella. One technique, Laurdan fluorescence microscopy, has proven very useful for distinguishing such regions but has hitherto relied on 2-photon confocal microscopy. This has to some extent limited its utility to living systems and its widespread adoption in studying membrane dynamics on the surface of living cells. Here we describe and validate the adaptation of a standard widefield fluorescence microscope for live imaging of Laurdan stained cell membranes.


Assuntos
Membrana Celular/química , Membrana Celular/ultraestrutura , Rim/metabolismo , Lipídeos/química , Macrófagos/metabolismo , Microdomínios da Membrana/química , 2-Naftilamina/análogos & derivados , Animais , Células Cultivadas , Colesterol/metabolismo , Cães , Corantes Fluorescentes , Processamento de Imagem Assistida por Computador , Rim/citologia , Lauratos , Microdomínios da Membrana/ultraestrutura , Camundongos , Trypanosoma rangeli/ultraestrutura
17.
BMC Genomics ; 13: 531, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-23035642

RESUMO

BACKGROUND: Trypanosoma cruzi marinkellei is a bat-associated parasite of the subgenus Schizotrypanum and it is regarded as a T. cruzi subspecies. Here we report a draft genome sequence of T. c. marinkellei and comparison with T. c. cruzi. Our aims were to identify unique sequences and genomic features, which may relate to their distinct niches. RESULTS: The T. c. marinkellei genome was found to be ~11% smaller than that of the human-derived parasite T. c. cruzi Sylvio X10. The genome size difference was attributed to copy number variation of coding and non-coding sequences. The sequence divergence in coding regions was ~7.5% between T. c. marinkellei and T. c. cruzi Sylvio X10. A unique acetyltransferase gene was identified in T. c. marinkellei, representing an example of a horizontal gene transfer from eukaryote to eukaryote. Six of eight examined gene families were expanded in T. c. cruzi Sylvio X10. The DGF gene family was expanded in T. c. marinkellei. T. c. cruzi Sylvio X10 contained ~1.5 fold more sequences related to VIPER and L1Tc elements. Experimental infections of mammalian cell lines indicated that T. c. marinkellei has the capacity to invade non-bat cells and undergo intracellular replication. CONCLUSIONS: Several unique sequences were identified in the comparison, including a potential subspecies-specific gene acquisition in T. c. marinkellei. The identified differences reflect the distinct evolutionary trajectories of these parasites and represent targets for functional investigation.


Assuntos
Quirópteros/parasitologia , Trypanosoma cruzi/genética , Trypanosoma/genética , Acetiltransferases/genética , Animais , Doença de Chagas/parasitologia , Biologia Computacional , Variações do Número de Cópias de DNA , DNA de Protozoário/genética , Ligação Genética , Humanos , Retroelementos/genética , Trypanosoma/classificação , Trypanosoma cruzi/classificação
18.
Mem Inst Oswaldo Cruz ; 107(7): 946-50, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23147154

RESUMO

In this study the effect of eight DNA topoisomerase inhibitors on the growth Trypanosoma rangeli epimastigotes in cell culture was investigated. Among the eight compounds tested, idarubicin was the only compound that displayed promising trypanocidal activity with a half-maximal growth inhibition (GI(50)) value in the sub-micromolar range. Fluorescence-activated cell sorting analysis showed a reduction in DNA content in T. rangeli epimastigotes when treated with idarubicin. In contrast to T. rangeli, against Trypanosoma cruzi epimastigotes idarubicin was much less effective exhibiting a GI(50) value in the mid-micromolar range. This result indicates that idarubicin displays differential toxic effects in T. rangeli and T. cruzi. Compared with African trypanosomes, it seems that American trypanosomes are generally less susceptible to DNA topoisomerase inhibitors.


Assuntos
Idarubicina/farmacologia , Inibidores da Topoisomerase/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma rangeli/efeitos dos fármacos , Citometria de Fluxo , Testes de Sensibilidade Parasitária , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma rangeli/crescimento & desenvolvimento
19.
Am Surg ; 88(4): 784-786, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34732081

RESUMO

Trauma is the leading cause of non-obstetrical maternal death. A 19-year-old woman at 20 weeks' gestation was brought to the emergency room after suffering a gunshot wound to the lower abdomen. Upon arrival, she was hemodynamically stable and imaging was obtained. CT revealed a rupture of the uterus with a partially extrauterine fetus, and the patient was immediately taken for an explorative laparotomy. Prior to the surgical start, the patient's blood pressure declined and, subsequently, a resuscitative endovascular balloon occlusion of the aorta (REBOA) was placed. The fetus and placenta were delivered and both uterine arteries and the inferior epigastric artery were ligated. Following an unremarkable postoperative course, she was discharged on hospital day 17. The mainstay approach to trauma in pregnancy should be to utilize focused imaging techniques to assess extent of trauma and provide adequate circulation to vital organs. Aortic balloon occlusion may be considered as a viable strategy to enhance resuscitation.


Assuntos
Oclusão com Balão , Procedimentos Endovasculares , Choque Hemorrágico , Ferimentos por Arma de Fogo , Adulto , Aorta/cirurgia , Oclusão com Balão/métodos , Procedimentos Endovasculares/métodos , Feminino , Humanos , Ressuscitação/métodos , Choque Hemorrágico/terapia , Útero , Ferimentos por Arma de Fogo/cirurgia , Adulto Jovem
20.
Comput Struct Biotechnol J ; 20: 6388-6402, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36420151

RESUMO

The kinetoplastids are unicellular flagellates that derive their name from the 'kinetoplast', a region within their single mitochondrion harboring its organellar genome of high DNA content, called kinetoplast (k) DNA. Some protein products of this mitochondrial genome are encoded as cryptogenes; their transcripts require editing to generate an open reading frame. This happens through RNA editing, whereby small regulatory guide (g)RNAs direct the proper insertion and deletion of one or more uridines at each editing site within specific transcript regions. An accurate perspective of the kDNA expansion and evolution of their unique uridine insertion/deletion editing across kinetoplastids has been difficult to achieve. Here, we resolved the kDNA structure and editing patterns in the early-branching kinetoplastid Trypanoplasma borreli and compare them with those of the well-studied trypanosomatids. We find that its kDNA consists of circular molecules of about 42 kb that harbor the rRNA and protein-coding genes, and 17 different contigs of approximately 70 kb carrying an average of 23 putative gRNA loci per contig. These contigs may be linear molecules, as they contain repetitive termini. Our analysis uncovered a putative gRNA population with unique length and sequence parameters that is massive relative to the editing needs of this parasite. We validated or determined the sequence identity of four edited mRNAs, including one coding for ATP synthase 6 that was previously thought to be missing. We utilized computational methods to show that the T. borreli transcriptome includes a substantial number of transcripts with inconsistent editing patterns, apparently products of non-canonical editing. This species utilizes the most extensive uridine deletion compared to other studied kinetoplastids to enforce amino acid conservation of cryptogene products, although insertions still remain more frequent. Finally, in three tested mitochondrial transcriptomes of kinetoplastids, uridine deletions are more common in the raw mitochondrial reads than aligned to the fully edited, translationally competent mRNAs. We conclude that the organization of kDNA across known kinetoplastids represents variations on partitioned coding and repetitive regions of circular molecules encoding mRNAs and rRNAs, while gRNA loci are positioned on a highly unstable population of molecules that differ in relative abundance across strains. Likewise, while all kinetoplastids possess conserved machinery performing RNA editing of the uridine insertion/deletion type, its output parameters are species-specific.

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