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1.
Front Aging Neurosci ; 14: 1026260, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36570533

RESUMO

Introduction: Alzheimer's (AD) and Parkinson's disease (PD) are neurodegenerative conditions characterized by incremental deposition of ß-amyloid (Aß) and α-synuclein in AD and PD brain, respectively, in relatively conserved patterns. Both are associated with neuroinflammation, with a proposed microbial component for disease initiation and/or progression. Notably, Aß and α-synuclein have been shown to possess antimicrobial properties. There is evidence for bacterial presence within the brain, including the oral pathobiont Porphyromonas gingivalis, with cognitive impairment and brain pathology being linked to periodontal (gum) disease and gut dysbiosis. Methods: Here, we use high resolution 16S rRNA PCR-based Next Generation Sequencing (16SNGS) to characterize bacterial composition in brain areas associated with the early, intermediate and late-stage of the diseases. Results and discussion: This study reveals the widespread presence of bacteria in areas of the brain associated with AD and PD pathology, with distinctly different bacterial profiles in blood and brain. Brain area profiles were overall somewhat similar, predominantly oral, with some bacteria subgingival and oronasal in origin, and relatively comparable profiles in AD and PD brain. However, brain areas associated with early disease development, such as the locus coeruleus, were substantially different in bacterial DNA content compared to areas affected later in disease etiology.

2.
Zootaxa ; 5141(5): 401-441, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36095779

RESUMO

Five new species are described in the genus Yoyetta Moulds, each belonging to the Yoyetta tristrigata (Goding and Froggatt) species group. Yoyetta australicta n. sp. occurs in southern eucalypt woodlands in two separate populations, one extending from the foothills of the Mt Lofty Ranges and southern fringes of Adelaide north to the Flinders Ranges, and the other from Warrumbungle National Park and from Clandulla, near Orange and near Grenfell in New South Wales south to Mt Taylor in the Australian Capital Territory. Yoyetta corindi n. sp. has a restricted, coastal and subcoastal warm temperate distribution in north-eastern New South Wales open forest communities between Trustums Hill and Arrawarra, extending inland from south-west of Grafton to Tyringham. Yoyetta delicata n. sp. has an inland warm temperate distribution in eucalypt woodland and open forest from near Killarney and west of Warwick in south-east Queensland south to Cassilis and near Wyong in central New South Wales. Yoyetta ignita n. sp. is found from Flinders Peak and Mt Tamborine in south-east Queensland, south along the Great Dividing Range (and inland to Mt Kaputar) in New South Wales, with a disjunct population on the eastern slopes of Mt Ainslie in the Australian Capital Territory. Yoyetta robusta n. sp. is found from the Granite Belt in south-east Queensland south to the Glenn Innes area in northern New South Wales. The new species are all smallmedium sized cicadas (1525 mm body length) with male calling songs that are distinguishable from one another and from other species in the genus. In three of the new species (Y. australicta n. sp., Y. corindi n. sp. and Y. robusta n. sp.), the songs are characterised by sharp, high energy ticks or clicks, produced mainly in flight. Each of these species also produces ticks or clicks, sometimes in combination with a short buzz, while stationary. Of the remaining two species, one (Y. delicata n. sp.) produces a soft, coarse buzzing song while stationary and the other (Y. ignita n. sp.) produces a combination of buzzes and clicks while stationary. A key to species in the Y. tristrigata species group is provided.


Assuntos
Hemípteros , Distribuição Animal , Animais , Austrália , Florestas , Fungos , Masculino
3.
Parasit Vectors ; 15(1): 161, 2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35526030

RESUMO

BACKGROUND: Among protozoan parasites in the genus Babesia, Babesia bigemina is endemic and widespread in the East African region while the status of the more pathogenic Babesia bovis remains unclear despite the presence of the tick vector, Rhipicephalus microplus, which transmits both species. Recent studies have confirmed the occurrence of R. microplus in coastal Kenya, and although B. bovis DNA has previously been detected in cattle blood in Kenya, no surveillance has been done to establish its prevalence. This study therefore investigated the occurrence of B. bovis in cattle in Kwale County, Kenya, where R. microplus is present in large numbers. METHODS: A species-specific multiplex TaqMan real-time PCR assay targeting two Babesia bovis genes, 18S ribosomal RNA and mitochondrially-encoded cytochrome b and B. bigemina cytochrome b gene was used to screen 506 cattle blood DNA samples collected from Kwale County for presence of Babesia parasite DNA. A sub-set of 29 B. bovis real-time PCR-positive samples were further amplified using a B. bovis-specific spherical body protein-4 (SBP-4) nested PCR and the resulting products sequenced to confirm the presence of B. bovis. RESULTS: A total of 131 animals (25.8%) were found to have bovine babesiosis based on real-time PCR. Twenty-four SBP4 nucleotide sequences obtained matched to B. bovis with a similarity of 97-100%. Of 131 infected animals, 87 (17.2%) were positive for B. bovis while 70 (13.8%) had B. bigemina and 26 (5.1%) were observed to be co-infected with both Babesia species. A total of 61 animals (12.1%) were found to be infected with B. bovis parasites only, while 44 animals (8.7%) had B. bigemina only. Babesia bovis and B. bigemina infections were detected in the three Kwale sub-counties. CONCLUSION: These findings reveal high prevalence of pathogenic B. bovis in a Kenyan area cutting across a busy transboundary livestock trade route with neighbouring Tanzania. The Babesia multiplex real-time PCR assay used in this study is specific and can detect and differentiate the two Babesia species and should be used for routine B. bovis surveillance to monitor the spread and establishment of the pathogen in other African countries where B. bigemina is endemic. Moreover, these findings highlight the threat of fatal babesiosis caused by B. bovis, whose endemic status is yet to be established. GRAPHICAL ABTRACT.


Assuntos
Babesia bovis , Babesia , Babesiose , Doenças dos Bovinos , Parasitos , Rhipicephalus , Animais , Babesia/genética , Babesia bovis/genética , Babesiose/epidemiologia , Babesiose/parasitologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Citocromos b/genética , DNA de Protozoário/genética , Quênia/epidemiologia , Parasitos/genética , Reação em Cadeia da Polimerase em Tempo Real , Rhipicephalus/genética
4.
Pathogens ; 10(9)2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34578185

RESUMO

Integrated parasite management (IPM) for pests, pathogens and parasites involves reducing or breaking transmission to reduce the impact of infection or infestation. For Theileria orientalis, the critical impact of infection is the first wave of parasitaemia from the virulent genotypes, Ikeda and Chitose, associated with the sequelae from the development of anaemia. Therefore, current control measures for T. orientalis advocate excluding the movement of naïve stock from non-endemic regions into infected areas and controlling the tick Haemaphysalislongicornis, the final host. In Australia, treatment of established infection is limited to supportive therapy. To update and expand these options, this review examines progress towards prevention and therapy for T. orientalis, which are key elements for inclusion in IPM measures to control this parasite.

5.
Hum Gene Ther ; 32(19-20): 1186-1199, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34477013

RESUMO

Despite the unequivocal success of hematopoietic stem and progenitor cell gene therapy, limitations still exist including genotoxicity and variegation/silencing of transgene expression. A class of DNA regulatory elements known as chromatin insulators (CIs) can mitigate both vector transcriptional silencing (barrier CIs) and vector-induced genotoxicity (enhancer-blocking CIs) and have been proposed as genetic modulators to minimize unwanted vector/genome interactions. Recently, a number of human, small-sized, and compact CIs bearing strong enhancer-blocking activity were identified. To ultimately uncover an ideal CI with a dual, enhancer-blocking and barrier activity, we interrogated these elements in vitro and in vivo. After initial screening of a series of these enhancer-blocking insulators for potential barrier activity, we identified three distinct categories with no, partial, or full protection against transgene silencing. Subsequently, the two CIs with full barrier activity (B4 and C1) were tested for their ability to protect against position effects in primary cells, after incorporation into lentiviral vectors (LVs) and transduction of human CD34+ cells. B4 and C1 did not adversely affect vector titers due to their small size, while they performed as strong barrier insulators in CD34+ cells, both in vitro and in vivo, shielding transgene's long-term expression, more robustly when placed in the forward orientation. Overall, the incorporation of these dual-functioning elements into therapeutic viral vectors will potentially provide a new generation of safer and more efficient LVs for all hematopoietic stem cell gene therapy applications.


Assuntos
Cromatina , Elementos Isolantes , Cromatina/genética , Elementos Facilitadores Genéticos , Terapia Genética , Vetores Genéticos/genética , Células-Tronco Hematopoéticas , Humanos , Elementos Isolantes/genética
6.
Vet Parasitol ; 298: 109532, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34325298

RESUMO

Theileria orientalis is a tick-borne protozoal parasite causing anaemia and death in susceptible cattle. This investigation aimed to confirm whether immunisation with the "benign" buffeli genotype of T. orientalis could reduce the parasitaemia of the virulent ikeda genotype. Calves were inoculated intravenously or subcutaneously with bovine blood containing merozoites of T. orientalis buffeli and when recipients became positive by PCR, they and control calves were challenged with unfed nymphs of Haemaphysalis longicornis ticks infected as larvae with T. orientalis ikeda. All calves became positive for the challenge within 12 days after tick application. In the immunised calves, the first wave of parasitaemia with T. orientalis ikeda from 4 to 6 weeks was reduced significantly by >80 % before the parasite burden declined into the carrier state by 9 weeks. The parasitaemias in two calves which exhibited low infections with T. orientalis ikeda shortly after arrival, were also significantly reduced after tick challenge. The results confirm the previous studies on immunity to T. sergenti in Japan, and field experience with theileriosis in endemic zones where the carrier state appears to prevent clinical disease despite repeated, seasonal tick infestations with virulent genotypes of the parasite. This method offers a means to reduce the severity of the first wave of theilerial parasitaemia after tick challenge and possibly recover associated production losses.


Assuntos
Doenças dos Bovinos , Theileria , Theileriose , Carrapatos , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Merozoítos , Parasitemia/veterinária , Theileria/genética , Theileriose/prevenção & controle
7.
Vet Parasitol ; 296: 109487, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34175676

RESUMO

BACKGROUND: In regions with endemic Theileria orientalis, recovered cattle are carriers, leaving newborn calves and introduced stock as the most susceptible groups to develop clinical disease after tick infestation with parasite transmission. METHODS: To gain information on the kinetics of infection and development and effects of theileriosis caused by virulent ikeda and chitose genotypes and the "benign" buffeli genotype of T.orientalis, this study sampled a total of 134 calves from 3 farms in Dorrigo, Australia, a region with multiple genotypes of the parasite. In addition, 30 introduced beef weaners were bled and weighed for 6 months after arrival. RESULTS: In both cohorts, parasitaemia with the ikeda and chitose (genotypes 1 & 2) of T.orientalis was detectable by PCR within 3-4 weeks in >95 % of the groups, with maximal gene copies generated around 5-7 weeks after birth or introduction, before declining. In contrast, parasitaemias of T.orientalis buffeli (genotype 3), increased slowly, with around 80 % of the population testing positive by PCR after 4 months. The parasitaemias of the buffeli genotype did not exceed 40,000 gene copies /ul and were similar to those exhibited by ikeda and chitose genotypes following the "first wave of parasitaemia" as cattle entered the carrier state. In the 30 introduced weaners, the early infection with T.orientalis ikeda and chitose also caused significant reductions in packed cell volume (PCV) and incurred an estimated 20Kg loss in weight gain; the latter had not been recovered by 6 months after introduction. CONCLUSIONS: The results support previous findings in other endemic regions of theileriosis, and imply that amelioration of the early high levels of parasitosis by the virulent genotypes could reduce the initial impact of theileriosis on production, which appears much less affected once animals enter the carrier state.


Assuntos
Doenças dos Bovinos , Theileria , Theileriose , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Genótipo , Estudos Longitudinais , New South Wales/epidemiologia , Theileria/classificação , Theileria/genética , Theileriose/epidemiologia , Theileriose/parasitologia , Aumento de Peso
8.
Prev Vet Med ; 193: 105394, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34119857

RESUMO

Ovine Johne's disease is a chronic debilitating disease of sheep caused by Mycobacterium avium subsp. paratuberculosis (Mptb) which results in diarrhoea, emaciation and mortalities in infected animals. Vaccination with Gudair® has been a key strategy for controlling the disease in Australia since its approval in 2002. Previous research conducted in Australia has demonstrated that the vaccine is quite effective in reducing sheep mortalities. While some farms have also been successful in reducing the prevalence of the disease in their flocks to undetectable levels, sheep in other flocks continue to shed Mptb in faeces even after an ongoing vaccination program . This study was conducted to investigate management, husbandry and biosecurity factors associated with paratuberculosis infection in Gudair® vaccinated sheep flocks in Australia. We enrolled 64 sheep farmers and interviewed them to obtain information about their management and biosecurity practices. Pooled faecal samples were collected from sheep at each farm and cultured to create two outcome variables: Mptb positive (yes/no) and disease prevalence level (nil, < 1 %, ≥ 1 %). Binary and ordinal logistic regression analyses were conducted to evaluate the association of management, husbandry and biosecurity factors with these outcome variables. Farms were more likely to have Mptb positive sheep and a higher disease prevalence in their flocks if they: (a) provided supplementary feed on the ground (instead of in a trough); (b) had a greater number of neighbours with sheep; and (c) had introduced rams from a greater number of sources. The results suggest the effectiveness of Gudair® vaccination to control OJD can be improved if sheep producers maintain other risk management strategies and biosecurity practices. Extension agencies should advise farmers not to relax their biosecurity practices and to purchase rams from only low-risk sources, even if they are continuing to vaccinate their flocks.


Assuntos
Vacinas Bacterianas , Paratuberculose , Doenças dos Ovinos , Animais , Austrália/epidemiologia , Masculino , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/epidemiologia , Paratuberculose/prevenção & controle , Ovinos/microbiologia , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/prevenção & controle
9.
Front Microbiol ; 12: 627327, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054743

RESUMO

Due to their vector capacity, ticks are ectoparasites of medical and veterinary significance. Modern sequencing tools have facilitated tick-associated microbiota studies, but these have largely focused on bacterial pathogens and symbionts. By combining 16S rRNA gene sequencing with total RNA-sequencing methods, we aimed to determine the complete microbiome and virome of questing, female Ixodes holocyclus recovered from coastal, north-eastern New South Wales (NSW), Australia. We present, for the first time, a robust and unbiased method for the identification of novel microbes in ticks that enabled us to identify bacteria, viruses, fungi and eukaryotic pathogens. The dominant bacterial endosymbionts were Candidatus Midichloria sp. Ixholo1 and Candidatus Midichloria sp. Ixholo2. Candidatus Neoehrlichia australis and Candidatus Neoehrlichia arcana were also recovered, confirming that these bacteria encompass I. holocyclus' core microbiota. In addition, seven virus species were detected-four previously identified in I. holocyclus and three novel species. Notably, one of the four previously identified virus species has pathogenic potential based on its phylogenetic relationship to other tick-associated pathogens. No known pathogenic eukaryotes or fungi were identified. This study has revealed the microbiome and virome of female I. holocyclus from the environment in north-eastern NSW. We propose that future tick microbiome and virome studies utilize equivalent methods to provide an improved representation of the microbial diversity in ticks globally.

10.
Vet Parasitol X ; 3: 100022, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32904744

RESUMO

The intracellular protozoal parasite Theileria orientalis ikeda has rapidly spread across South-eastern Australia since 2006, causing deaths and production losses in cattle. The 3-host "bush tick" Haemaphysalis longicornis (Neumann) appears the principal biological vector in the endemic regions. To generate sufficient numbers of ticks to produce stabilate for infection to confirm vector competency and for acaricide trials, the optimal conditions and stage-specific intervals for the generational life-cycle of H.longicornis was defined on two dogs and two steers. To determine whether H.longicornis was a definitive host for Theileria orientalis, nymphal stages were fed on a steer infected with T.orientalis and moulted adults were permitted to feed for 3 days on an uninfected calf prior to harvest. Subsequent detection of infection after inoculation of four naïve calves with stabilate produced from ground-up adult ticks or dissected salivary glands confirmed H.longicornis as one final (definitive) host for T.orientalis in Australia.

11.
Parasit Vectors ; 13(1): 432, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32854747

RESUMO

BACKGROUND: The tick vector Rhipicephalus microplus which transmits Babesia spp. and rickettsial pathogens has not been reported in Kenya since 1998. More recently, the pathogenic Babesia bovis has been detected in cattle blood DNA. The status of R. microplus in Kenya remains unknown. This study employed morphological and molecular tools to characterize R. microplus originating from Kenya and assess the genetic relationships between Kenyan and other African R. microplus genotypes. METHODS: Ticks were collected in south-eastern Kenya (Kwale County) from cattle and characterized to investigate the existence of R. microplus. Genetic and phylogenetic relationships between the Kenyan and other annotated R. microplus reference sequences was investigated by analysis of the cytochrome c oxidase subunit 1 (cox1) gene. To further characterize Kenyan ticks, we generated low coverage whole genome sequences of two R. microplus, one R. decoloratus and R. appendiculatus. A B. bovis specific TaqMan probe qPCR assay was used to detect B. bovis in gDNA from R. microplus ticks. RESULTS: Occurrence of R. microplus was confirmed in Kwale County, Kenya. The Kenyan R. microplus cox1 sequences showed very high pairwise identities (> 99%) and clustered very closely with reference African R. microplus sequences. We found a low genetic variation and lack of geographical sub-structuring among the African cox1 sequences of R. microplus. Four complete mitochondrial (mt) genomes for two R. microplus, one R. decoloratus and one R. appendiculatus were assembled from next generation sequence data. The mitochondrial genome sequences of the two Kenyan R. microplus ticks clustered closely with reference genome sequences from Brazil, USA, Cambodia and India forming R. microplus Clade A. No B. bovis was detected in the Kwale R. microplus DNA. CONCLUSIONS: These findings confirm the presence of R. microplus in Kenya and suggest that R. microplus Clade A is prevalent in cattle in sub-Saharan Africa. These and other recent findings of widespread occurrence of R. microplus in Africa provide a strong justification for urgent surveillance to determine and monitor the spread of R. microplus and vector competence of Boophilus ticks for B. bovis in Africa, with the ultimate goal of strategic control.


Assuntos
Babesia bovis/isolamento & purificação , Rhipicephalus , Infestações por Carrapato/veterinária , Animais , Vetores Aracnídeos/genética , Vetores Aracnídeos/parasitologia , Babesia bovis/genética , Bovinos , Doenças dos Bovinos/epidemiologia , Vetores de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/genética , Monitoramento Epidemiológico , Genes de Protozoários , Genoma Mitocondrial , Quênia/epidemiologia , Patologia Molecular/métodos , Filogenia , Rhipicephalus/genética , Rhipicephalus/parasitologia
12.
Int J Parasitol ; 50(8): 533-553, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32569640

RESUMO

This review addresses the research landscape regarding vaccines against scour worms, particularly Trichostrongylus spp. and Teladorsagia circumcincta. The inability of past research to deliver scour-worm vaccines with reliable and reproducible efficacy has been due in part to gaps in knowledge concerning: (i) host-parasite interactions leading to development of type-2 immunity, (ii) definition of an optimal suite of parasite antigens, and (iii) rational formulation and administration to induce protective immunity against gastrointestinal nematodes (GIN) at the site of infestation. Recent 'omics' developments enable more systematic analyses. GIN genomes are reaching completion, facilitating "reverse vaccinology" approaches that have been used successfully for the Rhipicephalus australis vaccine for cattle tick, while methods for gene silencing and editing in GIN enable identification and validation of potential vaccine antigens. We envisage that any efficacious scour worm vaccine(s) would be adopted similarly to "Barbervax™" within integrated parasite management schemes. Vaccines would therefore effectively parallel the use of resistant animals, and reduce the frequency of drenching and pasture contamination. These aspects of integration, efficacy and operation require updated models and validation in the field. The conclusion of this review outlines an approach to facilitate an integrated research program.


Assuntos
Ostertagíase/veterinária , Doenças Parasitárias em Animais/prevenção & controle , Ruminantes/parasitologia , Tricostrongilose/veterinária , Vacinas , Animais , Ostertagia , Ostertagíase/prevenção & controle , Tricostrongilose/prevenção & controle , Trichostrongylus
13.
Vet Parasitol ; 277S: 100022, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34392949

RESUMO

The intracellular protozoal parasite Theileria orientalis ikeda has rapidly spread across South-eastern Australia since 2006, causing deaths and production losses in cattle. The 3-host "bush tick" Haemaphysalis longicornis (Neumann) appears the principal biological vector in the endemic regions. To generate sufficient numbers of ticks to produce stabilate for infection to confirm vector competency and for acaricide trials, the optimal conditions and stage-specific intervals for the generational life-cycle of H.longicornis was defined on two dogs and two steers. To determine whether H.longicornis was a definitive host for Theileria orientalis, nymphal stages were fed on a steer infected with T.orientalis and moulted adults were permitted to feed for 3 days on an uninfected calf prior to harvest. Subsequent detection of infection after inoculation of four naïve calves with stabilate produced from ground-up adult ticks or dissected salivary glands confirmed H.longicornis as one final (definitive) host for T.orientalis in Australia.

14.
Front Cell Infect Microbiol ; 10: 577485, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33469518

RESUMO

The use of Next Generation Sequencing (NGS) techniques has generated a wide variety of blood microbiome data. Due to the large variation in bacterial DNA profiles between studies and the likely high concentrations of cell-free bacterial DNA in the blood, it is still not clear how such microbiome data relates to viable microbiota. For these reasons much remains to be understood about the true nature of any possible healthy blood microbiota and of bacteraemic events associated with disease. The gut, reproductive tracts, skin, and oral cavity are all likely sources of blood-borne bacteria. Oral bacteria, especially those associated with periodontal diseases, are also commonly associated with cardiovascular diseases such as infective endocarditis, and also have been linked to rheumatoid arthritis and Alzheimer's disease. Periodontal treatment, dental probing, and toothbrushing have been shown to cause transient bacteraemia and oral bacteria from the phyla Firmicutes (e.g. Streptococci) and Bacteroidetes (e.g. Porphyromonas) are found in cardiovascular lesions (CVD). Many studies of blood bacterial DNA content however, find Proteobacteria DNA to be the dominant microbiome component, suggesting a gut origin. Most studies of this type use total DNA extracted from either whole blood or blood fractions, such as buffy coat. Here, using a method that purifies DNA from intact bacterial cells only, we examined blood donated by those with active, severe periodontitis and periodontally healthy controls and show that 43-52% of bacterial species in blood are classified as oral. Firmicutes, consisting largely of members of the Streptococcus mitis group and Staphylococcus epidermidis, were predominant at 63.5% of all bacterial sequences detected in periodontal health and, little changed at 66.7% in periodontitis. Compared to studies using total DNA Proteobacteria were found here at relatively low levels in blood at 13.3% in periodontitis and 17.6% in health. This study reveals significant phylogenetic differences in blood bacterial population profiles when comparing periodontal health to periodontal disease cohorts.


Assuntos
Microbiota , Doenças Periodontais , Periodontite , Bactérias/genética , DNA Bacteriano/genética , Humanos , Filogenia
15.
Ticks Tick Borne Dis ; 11(1): 101305, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31594688

RESUMO

The brown dog tick Rhipicephalus sanguineus (Latreille, 1806) is the most widely distributed tick species globally. Throughout the world there are at least two divergent lineages on dogs that are traditionally grouped into what was known as R. sanguineus. The species R. sanguineus was recently redescribed using a neotype reported from countries with a temperate climate. The second lineage distributed in countries with primarily tropical climates is currently designated R. sanguineus s.l. tropical lineage. Here, we present a comprehensive genetic evaluation of Australian brown dog ticks from across the continent that complements the morphological study of R. sanguineus sensu Roberts (1965). A total of 294 ticks were collected from dogs around Australia - including New South Wales, Queensland, the Northern Territory and Western Australia - for morphological identification. All ticks were morphologically identified as R. sanguineus sensu Roberts (1965). DNA was isolated from a single leg from morphologically characterised individuals from New South Wales (n = 14), Queensland (n = 18), Northern Territory (n = 7) and Western Australia (n = 13), together with ticks from Fiji (n = 1) and the Seychelles (n = 1) for comparison with Australian ticks. The study revealed three cox1 haplotypes clustered only with R. sanguineus s.l. tropical lineage'. An updated distribution of R. sanguineus sensu Roberts (1965) is compared to the 1965 distribution. In the Australian context, R. sanguineus s.l. has appeared in north-western New South Wales but remains absent from coastal New South Wales. Despite both temperate and tropical climates being present in Australia, only R. sanguineus s.l. tropical lineage was found. The evidence does not support the presence of the strictly defined brown dog tick, R. sanguineus by Nava et al. (2018) in Australia, because the examined ticks are genetically and morphologically distinct. We recommend using the term brown dog tick, R. sanguineus sensu Roberts (1965) for specimens from Australia.


Assuntos
Distribuição Animal , Rhipicephalus sanguineus/classificação , Animais , Proteínas de Artrópodes/análise , Austrália , Complexo IV da Cadeia de Transporte de Elétrons/análise , Feminino , Haplótipos , Masculino , Ninfa/anatomia & histologia , Ninfa/classificação , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Óvulo/classificação , Óvulo/citologia , Óvulo/crescimento & desenvolvimento , Filogenia , Rhipicephalus sanguineus/anatomia & histologia , Rhipicephalus sanguineus/genética , Rhipicephalus sanguineus/crescimento & desenvolvimento
16.
Sci Total Environ ; 708: 134793, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31780147

RESUMO

Simulation and performance results of a saturated vertical up-flow constructed wetland (SVU CW) operated under different operational conditions are presented. The SVU CW consists of two different systems planted with Cyperus alternifolius and Iris pseudacorus, and each system consists of three SVU beds operated in series. The SVU CW operates in continuous aeration (CA) mode using different air-water ratios from 0.5:1 to 4:1. The aerated SVU CW achieves a high (more than 85%) removal of chemical oxygen demand (COD), ammonium (NH4+-N), total nitrogen (TN) and total phosphorus (TP). Furthermore, we simulate the SVU CW using the HYDRUS Wetland Module using the CWM1 biokinetic model under CA mode. According to the simulation results, aeration intensity controls the substrate distribution and growth of bacteria with depth in the SVU CW. Organic matter (OM) and nitrogen are removed in the top region (0-30 cm) of the SVU CW. The root mean square error for COD and NH4+-N is >1.5, whereas R2 is >0.99. A good match between observed and simulated data suggests that the CWM1 model is a suitable tool for simulating various processes and bacterial dynamics in aerated SVU CWs.


Assuntos
Gênero Iris , Áreas Alagadas , Análise da Demanda Biológica de Oxigênio , Nitrogênio , Fósforo , Eliminação de Resíduos Líquidos
17.
Folia Parasitol (Praha) ; 662019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31332102

RESUMO

Despite the global distribution of the brown dog tick, Rhipicephalus sanguineus (Latreille, 1806) sensu lato (s.l.), limited information exists about their identity from the Arabian Peninsula. Ticks from free roaming urban dogs and dromedary camels in Riyadh, Saudi Arabia were morphologically identified, confirmed with scanning electron microscopy and characterised at mitochondrial DNA (cox1, 12S rDNA and 16S rDNA). A total of 186 ticks were collected from 65 free roaming dogs (n = 73) and 84 dromedary camels (n = 113). Morphologically, 5.9% (11/186) were R. sanguineus s.l. and Hyalomma spp. (93.5%, 174/186). From within R. sanguineus s.l., the presence of Rhipicephalus cf. camicasi Morel, Mouchet et Rodhain, 1976 (1 dog, 2 camels) and Rhipicephalus turanicus Pomerantsev, 1936 (1 camel) is reported. The examined R. cf. camicasi form a sister group to R. sanguineus s.l. tropical lineage at all DNA markers. Dogs were parasitised by Hyalomma dromedarii Koch, 1844 (n = 59), Hyalomma impeltatum Schulze et Schlottke, 1930 (n = 1), Hyalomma excavatum Koch, 1844 (n = 2), Hyalomma turanicum Pomerantsev, 1946 (n = 1) and Hyalomma rufipes Koch,1844 (n = 1). DNA from dog blood (n = 53) from Riyadh confirmed a low prevalence of canine vector-borne pathogens that does not exceed 5.7% for Babesia spp., Mycoplasma spp., Anaplasma platys, Hepatozoon canis and Ehrlichia canis using multiplexed tandem PCR (MT-PCR) and diagnostic PCR. Low prevalence of R. sanguineus s.l. on dogs likely contributed to the low level of canine vector-borne pathogens in Saudi Arabia. We demonstrate that dogs in the central Arabian Peninsula are more commonly parasitised by Hyalomma spp. than R. sanguineus s.l.


Assuntos
Vetores Aracnídeos/microbiologia , Vetores Aracnídeos/parasitologia , Doenças do Cão/epidemiologia , Ixodidae/microbiologia , Ixodidae/parasitologia , Doenças Transmitidas por Vetores/veterinária , Animais , Vetores Aracnídeos/classificação , Camelus , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Feminino , Ixodidae/classificação , Masculino , Prevalência , Rhipicephalus sanguineus/microbiologia , Rhipicephalus sanguineus/parasitologia , Arábia Saudita/epidemiologia , Doenças Transmitidas por Vetores/epidemiologia , Doenças Transmitidas por Vetores/microbiologia , Doenças Transmitidas por Vetores/parasitologia
18.
Anal Chem ; 91(9): 6281-6287, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30969104

RESUMO

A tandem ion mobility spectrometer at ambient pressure with a reactive stage produced fragment ions by water elimination from protonated monomers of alcohols with carbon numbers three to nine. Protonated monomers of individual alcohols were mobility isolated in a first drift region and were fragmented to carbocations at 64 to 128 Td and 45 to 89°C. Precursor and fragment ions were mobility characterized in a second drift region. Enthalpies for fragmentation of ROH2+ to primary carbocations were calculated as 76 to 97 kJ/mol and enthalpies for subsequent charge migration to 2° carbocations were -49 to -58 kJ/mol. Plots of drift times for pairs of protonated monomer and fragment ions from alcohols, esters, alkanes, and aldehydes produced distinctive trend lines attributed to fragmentation paths characteristic of chemical class. Specific combinations of drift times for fragments and precursor ions provide additional chemical information for spectral interpretation in ion mobility spectrometry.

19.
Parasit Vectors ; 12(1): 85, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30782195

RESUMO

Since publication of the original version of this article [1], it has been flagged that unfortunately there is an error in dosage units in the Discussion section, in the sentence "For example a microfilaricide, either ivermectin (50-200 mg/kg) or milbemycin oxime (500-1,000 mg/kg)".

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