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1.
Appl Radiat Isot ; 190: 110480, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36209648

RESUMO

Terbium-155 has been identified for its potential for single-photon emission computed tomography (SPECT) in nuclear medicine. For activity measurements, an accurate and precise half-life of this radionuclide is required. However, the currently evaluated half-life of 5.32(6) d with a relative standard uncertainty of 1.1% determines the precision possible. Limited literature for the half-life measurements of this radionuclide is available and all reported investigations are prior to 1970. Further measurements are therefore needed to confirm the accuracy and improve the precision of the half-life for its use in the clinical setting. Two samples produced and mass separated at the CERN-MEDICIS facility have been measured at the National Physical Laboratory by two independent techniques: liquid scintillation counting and high-purity germanium gamma-ray spectrometry. A half-life of 5.2346(36) d has been determined from the weighted mean of the half-lives determined by the two techniques. The half-life reported in this work has shown a relative difference of 1.6% to the currently evaluated half-life and has vastly improved the precision.


Assuntos
Medicina Nuclear , Radioisótopos , Meia-Vida , Radioisótopos/análise , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Espectrometria gama
2.
Sci Total Environ ; 785: 147246, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33940419

RESUMO

Reservoir presence and construction has become commonplace along rivers due to the multitude of ecosystem services they provide. Many services are well recognized, including the effectiveness of sequestering both sediments and sediment-bound nutrients such as silts and phosphorus (P). Reservoirs are also capable of transforming or sequestering significant quantities of nutrients with more complex biogeochemical pathways, like nitrogen (N). Reservoir assessments, independent of inflow-outflow models, have primarily focused on a small number of systems creating a growing need to understand how reservoirs function both individually and as reservoir sequences within large rivers and their watersheds. Models have simulated the overall efficiency and drivers of reservoir nutrient deposition, but few have considered how a sequence of reservoirs alters deposition as an interdependent watershed-sediment-transport-system. In this study, we collected sediment cores from a six-reservoir sequence along a 5th - 6th order stream receiving treated waters from a large metropolitan area in the subtropical southeastern United States. Paleolimnological studies of subtropical reservoirs are underrepresented and are needed to understand the history of reservoir development. Using paleolimnological techniques and a known 30 year flux of riverine nutrient loading from waste water treatment facilities, we compared nutrient deposition to reservoir morphological qualities and primary producer community structure during the past ~50 years. Our findings suggest phosphorus deposition is associated with reservoir order downstream of the primary nutrient source, nitrogen deposition is linked to reservoir water retention time, and N:P is most strongly linked to reservoir surface area and watershed population density. Our results were strongly influenced by a large upstream and metropolitan nutrient source, common in large rivers, but under different conditions of nutrient loading (i.e. nonpoint source), reservoirs may express other nutrient depositional patterns.

3.
Infect Genet Evol ; 89: 104727, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33486128

RESUMO

Blood flukes within the genus Schistosoma (schistosomes) are responsible for the major disease, schistosomiasis, in tropical and sub-tropical areas. This disease is predominantly present on the African continent with more than 85% of the human cases. Schistosomes are also parasites of veterinary importance infecting livestock and wildlife. Schistosoma population genetic structure and diversity are important characteristics that may reflect variations in selection pressures such as those induced by host (mammalian and snail) environments, habitat change, migration and also treatment/control interventions, all of which also shape speciation and evolution of the whole Schistosoma genus. Investigations into schistosome population genetic structure, diversity and evolution has been an area of important debate and research. Supported by advances in molecular techniques with capabilities for multi-locus genetic analyses for single larvae schistosome genetic investigations have greatly progressed in the last decade. This paper aims to review the genetic studies of both animal and human infecting schistosome. Population genetic structures are reviewed at different spatial scales: local, regional or continental (i.e. phylogeography). Within species genetic diversities are discussed compared and the compounding factors discussed, including the effect of mass drug administration. Finally, the ability for intra-species hybridisation questions species integrities and poses many questions in relation to the natural epidemiology of co-endemic species. Here we review molecularly confirmed hybridisation events (in relation to human disease) and discuss the possible impact for ongoing and future control and elimination.


Assuntos
Schistosoma/genética , Esquistossomose/epidemiologia , África/epidemiologia , Animais , Humanos , Hibridização Genética
4.
Plant Dis ; 103(8): 2108-2112, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31215853

RESUMO

Clavibacter nebraskensis is the causal agent of Goss's leaf blight and wilt, an important disease of maize in the United States and Canada. The epidemiology and ecology of this bacterial pathogen are poorly understood. Infested maize residue is often considered to be the primary source of inoculum for maize; however, the potential for many other plant species to be infected and serve as inoculum sources is unknown. The goal of this study was to determine if C. nebraskensis could infect, survive, and grow on common weed, crop, and grass species. Seedling leaves of 18 plant species that grow in maize production areas in the United States were inoculated with this pathogen in a controlled environment and in the field. Lesion development, bacterial streaming, and pathogen population size on leaves were then determined and used as criteria to evaluate host-pathogen interactions. Woolly cupgrass (Eriochloa villosa) and the native prairie grasses big bluestem (Andropogon gerardii) and little bluestem (Schizachyrium scoparium) developed lesions and bacterial streaming, identifying them as hosts and susceptible to infection. To our knowledge, this is the first report of these grass species being hosts of C. nebraskensis. Ten other grass species, including wheat and oats, were identified as potential sustaining hosts that maintained epiphytic or endophytic pathogen populations >106 colony forming units per leaf sample but displayed no evidence of infection. Five broadleaf species tested were nonhosts based on the three criteria. This study suggests that multiple plant species support infection and growth of C. nebraskensis and further elucidates the ecology of this pathogen and the epidemiology of Goss's wilt.


Assuntos
Micrococcaceae , Plantas , Canadá , Pradaria , Especificidade de Hospedeiro , Viabilidade Microbiana , Micrococcaceae/crescimento & desenvolvimento , Micrococcaceae/fisiologia , Plantas/microbiologia , Poaceae/microbiologia , Zea mays/microbiologia
5.
BMC Vet Res ; 15(1): 27, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30646904

RESUMO

BACKGROUND: Producing graduates for a breadth of sectors is a priority for veterinary science programs. Undergraduate career intentions represent de-facto 'outcome' measures of admissions policy and curricula design, as intentions are strong predictors of eventual behaviour. Informed by Ajzen's Theory of Planned Behaviour, this study aimed to identify if contextually relevant attitudes and self-ratings affect student intentions for veterinary career sectors. RESULTS: Survey responses from 844 students enrolled in five Australian veterinary programs in 2014 were analysed. Intention was measured for biomedical research/academia, industry, laboratory animal medicine, public health/government/diagnostic laboratory services, mixed practice, intensive animal production, companion animal practice, not work in the veterinary profession, and business/entrepreneurship. Hierarchical multiple linear regression analysis enabled comparison of explanation of variance in intent by demographics, animal handling experience, species preference, and attitudes to aspects of veterinary work. Career sector intentions were highest for mixed or companion animal clinical practice, then business/entrepreneurship, then non-clinical sectors. Overall, intent was explained to a greater extent by species preferences than by animal experience, attitudes to aspects of veterinary work and demographics (with the exception of mixed practice intent) with gender having no significant effect. Several variables exerted negative effects on career intent for less popular career sectors. CONCLUSION: Ajzen's Theory of Planned Behaviour (TPB) provides a framework to increase understanding of and predict career sector intentions. Incorporation of attitude and self-efficacy measures in our study revealed preference for species types contributes greatly to career sector intentions for veterinary students, particularly for the more popular practice based sectors. Importantly, specific species preferences and other attitudes can have a negative effect on intent for non-aligned veterinary sectors. Further research is required to identify additional attitudes and/or beliefs to better explain variance in intent for less popular career sectors. Veterinary admissions processes may benefit from utilising the TPB framework. Identified effects revealed by this study may stimulate innovation in marketing, recruitment, admissions and curricular design, such as timing and role modelling, to utilise positive effects and mitigate against negative effects identified for sectors requiring greater representation of career intent in the student body.


Assuntos
Escolha da Profissão , Medicina Veterinária , Atitude , Austrália , Estudos Transversais , Demografia , Feminino , Humanos , Masculino , Medicina Veterinária/tendências , Recursos Humanos
6.
Parasitology ; 145(13): 1641-1646, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30185237

RESUMO

The study of parasites typically crosses into other research disciplines and spans across diverse scales, from molecular- to populational-levels, notwithstanding promoting an understanding of parasites set within evolutionary time. Today, the 2030 Sustainable Development Goals (SDGs) help frame much of contemporary parasitological research, since parasites can be found in all ecosystems, blighting human, animal and plant health. In recognition of the multi-disciplinary nature of parasitological research, the 2017 Autumn Symposium of the British Society for Parasitology was held in London to provide a forum for novel exchange across medical, veterinary and wildlife fields of study. Whilst the meeting was devoted to the topic of parasitism, it sought to foster mutualism, the antithesis perhaps of parasitism, by forging new academic connections and social networks to exchange novel ideas. The meeting also celebrated the longstanding career of Professor David Rollinson, FLS in the award of the International Federation for Tropical Medicine Medal for his efforts spanning 40 years of parasitological research. Indeed, David has done so much to explore and promote the fascinating biology of parasitism, as exemplified by the 15 manuscripts contained within this Special Issue.


Assuntos
Parasitologia/educação , Parasitologia/tendências , Animais , Congressos como Assunto , Humanos , Londres , Parasitos , Pesquisa , Medicina Tropical
7.
Adv Parasitol ; 92: 117-41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27137445

RESUMO

Schistosoma japonicum is the main schistosome species in The People's Republic of China, causing intestinal schistosomiasis, a debilitating disease of public health importance. The People's Republic of China used to be heavily endemic with schistosomiasis, but great progress has been made through the vigorous efforts of the national control programmes in the last six decades. Presently, efforts are geared towards eliminating schistosomiasis from The People's Republic of China by the end of 2025 through effective schistosomiasis surveillance, an important component in the drive towards schistosomiasis elimination. Therefore, this article explicitly outlines the development and progress made in schistosomiasis surveillance since 1990 with a special focus on the new surveillance system in use. Although the surveillance system has steadily improved over the years, it is faced with many challenges. Hence, more efforts are needed to establish an effective and sensitive evaluation system for the national schistosomiasis elimination programme in The People's Republic of China.


Assuntos
Erradicação de Doenças , Monitoramento Epidemiológico , Schistosoma japonicum/fisiologia , Esquistossomose Japônica/epidemiologia , Animais , China/epidemiologia , Geografia , Humanos , Saúde Pública , Esquistossomose Japônica/parasitologia , Esquistossomose Japônica/prevenção & controle
8.
Parasit Vectors ; 8: 519, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26453014

RESUMO

Unfortunately, the original version of this article [1], contained a mistake. In Table 1, the primers for Sh6 and Sh9 were included incorrectly. Instead of GGGATGTATGCAGACTTG TTGTTTGGCTGCAGTAAC and GCTGAGCTTGAGATTG CTTCTGTCCCATCGATACC they should have been Sh6 Forward Primer GGTGGATTACGCAATAG, Sh6 Reverse Primer TTTAATCAACCGGGTGTC and Sh9 Forward Primer GGGATGTATGCAGACTTG, Sh9 Reverse Primer TTGTTTGGCTGCAGTAAC respectively. A corrected version of Table 1 is included below

9.
Intern Med J ; 45(11): 1147-53, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26337606

RESUMO

BACKGROUND: Elderly patients with diffuse large B-cell lymphoma (DLBCL) have an inferior prognosis, due in part to advanced age and pre-existing comorbidities, with reduced tolerability and deliverability of standard R-CHOP chemotherapy. AIMS: To examine the deliverability, toxicity and efficacy of R-CHOP and the prevalence of the germinal and non-germinal phenotype DLBCL in an elderly Australian cohort. METHODS: This retrospective analysis included patients ≥75 years diagnosed with DLBCL. Comprehensive chemotherapy and toxicity data were collected for patients treated with R-CHOP. Baseline demographics and chemotherapy characteristics were compared with progression-free (PFS) and overall survival (OS). Immunohistochemical staining identified the prevalence of the non-germinal centre (non-GCB) phenotype. RESULTS: Of the 111 patients, 92 (83%) commenced R-CHOP with 26/92 (28%) receiving ≤4 cycles. Median average relative dose (ARD) was 0.80 (0.07-1.17). Median average relative dose intensity (ARDI) was 0.89 (0.33-1.18). Serious adverse events occurred in 77% of patients with ≥Gd3 adverse events in 74%. Overall response rate was 85%. Two-year PFS was 63% and OS 74%. ARD and performance status ≥2 were significant prognostic factors for PFS and OS but not ARDI. Non-GCB-phenotype was identified in 44/72 (61%) of patients with immunohistochemical data. CONCLUSION: Despite high response rates and respectable survival estimates, the absence of standard therapy in 17% of patients, and dose reductions and serious toxicity of R-CHOP in this Australian cohort highlights the need for the development of less toxic yet efficacious treatments for very elderly patients with DLBCL. The high prevalence of the non-GCB phenotype highlights the potential value of targeted biological therapy for this demographic.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Murinos/administração & dosagem , Austrália/epidemiologia , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Masculino , Prednisona/administração & dosagem , Estudos Retrospectivos , Rituximab , Taxa de Sobrevida/tendências , Resultado do Tratamento , Vincristina/administração & dosagem
10.
Parasit Vectors ; 8: 432, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-26329827

RESUMO

BACKGROUND: Human urogenital schistosomiasis caused by Schistosoma haematobium is widely distributed across Africa and is increasingly targeted for control and regional elimination. The development of new high-throughput, cost-effective molecular tools and approaches are needed to monitor and evaluate the impact of control programs on the parasite populations. Microsatellite loci are genetic markers that can be used to investigate how parasite populations change over time and in relation to external influences such as control interventions. FINDINGS: Here, 18 existing S. haematobium microsatellite loci were optimised to enable simultaneous amplification across two novel multiplex microsatellite PCR's, each containing nine loci. Methods were developed for the cost effective and rapid processing and microsatellite analysis of S. haematobium larval stages stored on Whatman-FTA cards and proved robust on miracidia and cercariae collected from Zanzibar and Niger. CONCLUSION: The development of these novel and robust multiplex microsatellite assays, in combination with an improved protocol to elute gDNA from Whatman-FTA fixed schistosome larval stages, enables the high-throughput population genetic analysis of S. haematobium. The molecular resources and protocols described here advance the way researchers can perform multi locus-based population genetic analyses of S. haematobium as part of the evaluation and monitoring of schistosomiasis control programmes.


Assuntos
Variação Genética , Repetições de Microssatélites , Reação em Cadeia da Polimerase Multiplex/métodos , Schistosoma haematobium/classificação , Schistosoma haematobium/genética , Animais , Análise Custo-Benefício , Genética Populacional , Humanos , Larva/classificação , Larva/genética , Níger , Schistosoma haematobium/isolamento & purificação , Esquistossomose Urinária/parasitologia , Tanzânia , Fatores de Tempo , Infecções Urinárias/parasitologia
11.
Parasit Vectors ; 8: 446, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26338510

RESUMO

BACKGROUND: Accurate diagnosis of urogenital schistosomiasis is vital for surveillance/control programs. Amplification of schistosome DNA in urine by PCR is sensitive and specific but requires infrastructure, financial resources and skilled personnel, often not available in endemic areas. Recombinase Polymerase Amplification (RPA) is an isothermal DNA amplification/detection technology that is simple, rapid, portable and needs few resources. FINDINGS: Here a Schistosoma haematobium RPA assay was developed and adapted so that DNA amplicons could be detected using oligochromatographic Lateral Flow (LF) strips. The assay successfully amplified S. haematobium DNA at 30-45 °C in 10 mins and was sensitive to a lower limit of 100 fg of DNA. The assay was also successful with the addition of crude urine, up to 5% of the total reaction volume. Cross amplification occurred with other schistosome species but not with other common urine microorganisms. CONCLUSION: The LF-RPA assay developed here can amplify and detect low levels of S. haematobium DNA. Reactions are rapid, require low temperatures and positive reactions are interpreted using lateral flow strips, reducing the need for infrastructure and resources. This together with an ability to withstand inhibitors within urine makes RPA a promising technology for further development as a molecular diagnostic tool for urogenital schistosomiasis.


Assuntos
Cromatografia/métodos , DNA de Helmintos/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Schistosoma haematobium/genética , Animais , Reações Cruzadas , Humanos , Projetos Piloto , Sensibilidade e Especificidade
12.
Reprod Domest Anim ; 49(6): 903-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25244510

RESUMO

Due to declining dairy cow fertility rates, there is great interest in developing tools for oestrus detection. Compounds in the volatile profile of oestrous cows are suggested as oestrus-specific, but consistent results have not been presented. Certain haematophagous arthropods can discriminate stages of the mammalian reproductive cycle based on host volatiles. This study investigated whether the face fly, Musca autumnalis de Geer (Diptera: Muscidae), can discriminate between urine from cows in oestrus and urine collected during the luteal phase. Individual flies were tested in a two-choice behavioural assay with choice between odour of oestrous or luteal urine and water (control). Flies chose the control arm significantly more when exposed to oestrous urine than when exposed to luteal urine. Analysis of volatiles showed that 1-hexadecanol (cetyl alcohol) was released in greater amounts from oestrous urine than from urine collected during the luteal phase. In a dose response assay, flies were significantly attracted by 0.01 ng of 1-hexadecanol but significantly repelled by 0.1 ng, a pattern consistent with fly responses to urine. In conclusion, M. autumnalis can discriminate between oestrous and luteal urine, and this may be mediated by differences in 1-hexadecanol concentration.


Assuntos
Bovinos/fisiologia , Bovinos/urina , Ciclo Estral/fisiologia , Muscidae/fisiologia , Odorantes , Animais , Técnicas Biossensoriais , Álcoois Graxos , Feminino
13.
Infect Genet Evol ; 18: 100-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23684792

RESUMO

The Senegal River Basin (SRB) experienced a major epidemic of intestinal schistosomiasis in the early nineties, after the construction of a dam for irrigation purposes. Exceptionally low cure rates following praziquantel (PZQ) treatment at the onset of the epidemic raised concerns about PZQ resistant strains of Schistosoma mansoni, although they could also be attributed to the intense transmission at that time. A field study in the same region more than 15 years later found cure rates for S. mansoni still to be low, whereas Schistosomahaematobium responded well to treatment. We collected S. mansoni miracidia from children at base-line prior to treatment, six months after two PZQ treatments and two years after the start of the study when they had received a total of five PZQ treatments. In total, 434 miracidia from 12 children were successfully genotyped with at least six out of nine DNA microsatellite loci. We found no significant differences in the genetic diversity of, and genetic differentiation between parasite populations before and after repeated treatment, suggesting that PZQ treatment does not have an impact on the neutral evolution of the parasite. This is in stark contrast with a similar study in Tanzania where a significant decrease in genetic diversity was observed in S. mansoni miracidia after a single round of PZQ treatment. We argue that PZQ resistance might play a role in our study area, although rapid re-infection cannot be excluded. It is important to monitor this situation carefully and conduct larger field studies with short-term follow-up after treatment. Since PZQ is the only general schistosomicide available, the possibility of PZQ resistance is of great concern both for disease control and for curative use in clinical practice.


Assuntos
Anti-Helmínticos/farmacologia , Praziquantel/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/genética , Esquistossomose mansoni/parasitologia , Animais , Análise por Conglomerados , Resistência a Medicamentos , Fezes/parasitologia , Variação Genética , Genótipo , Humanos , Epidemiologia Molecular , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/epidemiologia , Senegal/epidemiologia
14.
Clin Neuropsychol ; 27(4): 693-707, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23510271

RESUMO

This study examined differences in raw scores on the Symptom Validity Scale and Response Bias Scale (RBS) from the Minnesota Multiphasic Personality Inventory-2 in three criterion groups: (i) valid traumatic brain injured, (ii) invalid traumatic brain injured, and (iii) psychogenic non-epileptic seizure disorders. Results indicate that a >30 raw score cutoff for the Symptom Validity Scale accurately identified 50% of the invalid traumatic brain injured group, while misclassifying none of the valid traumatic brain injured group and 6% of the psychogenic non-epileptic seizure disorder group. Using a >15 RBS raw cutoff score accurately classified 50% of the invalid traumatic brain injured group and misclassified fewer than 10% of the valid traumatic brain injured and psychogenic non-epileptic seizure disorder groups. These cutoff scores used conjunctively did not misclassify any members of the psychogenic non-epileptic seizure disorder or valid traumatic brain injured groups, while accurately classifying 44% of the invalid traumatic brain injured individuals. Findings from this preliminary study suggest that the conjunctive use of the Symptom Validity Scale and the RBS from the Minnesota Multiphasic Personality Inventory-2 may be useful in differentiating probable malingering from individuals with brain injuries and conversion disorders.


Assuntos
Viés , Lesões Encefálicas/psicologia , Transtorno Conversivo/psicologia , Simulação de Doença/psicologia , Inventário de Personalidade , Adulto , Análise de Variância , Avaliação da Deficiência , Epilepsia/diagnóstico , Epilepsia/psicologia , Feminino , Humanos , Masculino , Simulação de Doença/diagnóstico , Pessoa de Meia-Idade , Probabilidade , Reprodutibilidade dos Testes
15.
Persoonia ; 28: 138-82, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23105159

RESUMO

Novel species of microfungi described in the present study include the following from Australia: Phytophthora amnicola from still water, Gnomoniopsis smithogilvyi from Castanea sp., Pseudoplagiostoma corymbiae from Corymbia sp., Diaporthe eucalyptorum from Eucalyptus sp., Sporisorium andrewmitchellii from Enneapogon aff. lindleyanus, Myrmecridium banksiae from Banksia, and Pilidiella wangiensis from Eucalyptus sp. Several species are also described from South Africa, namely: Gondwanamyces wingfieldii from Protea caffra, Montagnula aloes from Aloe sp., Diaporthe canthii from Canthium inerne, Phyllosticta ericarum from Erica gracilis, Coleophoma proteae from Protea caffra, Toxicocladosporium strelitziae from Strelitzia reginae, and Devriesia agapanthi from Agapanthus africanus. Other species include Phytophthora asparagi from Asparagus officinalis (USA), and Diaporthe passiflorae from Passiflora edulis (South America). Furthermore, novel genera of coelomycetes include Chrysocrypta corymbiae from Corymbia sp. (Australia), Trinosporium guianense, isolated as a contaminant (French Guiana), and Xenosonderhenia syzygii, from Syzygium cordatum (South Africa). Pseudopenidiella piceae from Picea abies (Czech Republic), and Phaeocercospora colophospermi from Colophospermum mopane (South Africa) represent novel genera of hyphomycetes. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

16.
J R Army Med Corps ; 158(2): 120-2, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22860502

RESUMO

OBJECTIVES: In the United Kingdom, approximately eight million peripheral cannulations are performed each year. Intravenous cannulae are made from either polytetrafluoroethylene (Teflon) or polyurethane. Polyurethane has a lower incidence of thrombophlebitis, however the physical characteristics of polyurethane may make the cannulae difficult to use at higher ambient temperatures. This effect maybe of importance to those involved in cannulation in extreme environments and especially for military doctors deployed in current theatres of operations. METHODS: In a randomised single blinded study we investigated the different characteristics of Teflon and polyurethane cannulae (Vasofix Safety Cannulae, B Braun) at three different temperatures (-10 degrees C, 21 degrees C and 40 degrees C). RESULTS: There is no statistically significant difference in the ease or speed of cannulation of either polyurethane or Teflon safety cannulae in extremes of temperature. CONCLUSIONS: This study provides evidence that performance of polyurethane safety cannulae are not impaired by temperature extremes.


Assuntos
Catéteres/efeitos adversos , Temperatura Baixa , Temperatura Alta , Politetrafluoretileno/efeitos adversos , Poliuretanos/efeitos adversos , Cateterismo , Humanos , Método Simples-Cego , Estatísticas não Paramétricas , Tromboflebite/etiologia , Fatores de Tempo
17.
Mol Phylogenet Evol ; 63(3): 834-47, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22406529

RESUMO

The construction of a stable phylogeny for the Cestoda, indicating the interrelationships of recognised orders and other major lineages, has proceeded iteratively since the group first received attention from phylogenetic systematists. Molecular analyses using nuclear ribosomal RNA gene fragments from the small (ssrDNA) and large (lsrDNA) subunits have been used to test competing evolutionary scenarios based on morphological data but could not arbitrate between some key conflicting hypotheses. To the ribosomal data, we have added a contiguous fragment of mitochondrial (mt) genome data (mtDNA) of partial nad1-trnN-trnP-trnI-trnK-nad3-trnS-trnW-cox1-trnT-rrnL-trnC-partial rrnS, spanning 4034-4447 bp, where new data for this region were generated for 18 species. Bayesian analysis of mtDNA and rDNA as nucleotides, and where appropriate as amino acids, demonstrated that these two classes of genes provide complementary signal across the phylogeny. In all analyses, except when using mt amino acids only, the Gyrocotylidea is sister group to all other Cestoda (Nephroposticophora), and Amphilinidea forms the sister group to the Eucestoda. However, an earliest-diverging position of Amphilinidea is strongly supported in the mt amino acid analysis. Amphilinidea exhibit a unique tRNA arrangement (nad1-trnI-trnL2-trnP-trnK-trnV-trnA-trnN-nad3), whereas Gyrocotylidea shares that of the derived lineages, providing additional evidence of the uniqueness of amphilinid genes and genomes. The addition of mtDNA to the rDNA genes supported the Caryophyllidea as the sister group to (Spathebothriidea+remaining Eucestoda), a hypothesis consistently supported by morphology. This relationship suggests a history of step-wise evolutionary transitions from simple monozoic, unsegmented tapeworms to the more familiar polyzoic, externally segmented (strobilate) forms. All our data partitions recovered Haplobothriidea as the sister group to Diphyllobothriidae. The sister-group relationship between Diphyllidea and Trypanorhyncha, as previously established using rDNA, is not supported by the mt data, although it is supported by the combined mt and rDNA analysis. With regards to the more derived taxa, in all except the mt amino acid analysis, the following topology is supported: (Bothriocephalidea (Litobothriidea (Lecanicephalidea (Rhinebothriidea (Tetraphyllidea, (Acanthobothrium, Proteocephalidea), (Nippotaeniidea, Mesocestoididae, Tetrabothriidea, Cyclophyllidea)))))), where the Tetraphyllidea are paraphyletic. Evidence from the mt data provides strong (nucleotides) to moderate (amino acids) support for Tetraphyllidea forming a group to the inclusion of Proteocephalidea, with the latter consistently forming the sister group to Acanthobothrium. The interrelationships among Nippotaeniidea, Mesocestoididae, Tetrabothriidea and Cyclophyllidea remain ambiguous and require further systematic attention. Mitochondrial and nuclear rDNA data provide conflicting signal for certain parts of the cestode tree. In some cases mt data offer results in line with morphological evidence, such as the interrelationships of the early divergent lineages. Also, Tetraphyllidea, although remaining paraphyletic with the inclusion of the Proteocephalidea, does not include the most derived cestodes; a result which has consistently been obtained with rDNA.


Assuntos
Cestoides/genética , DNA Mitocondrial/genética , Animais , Teorema de Bayes , Cestoides/anatomia & histologia , Cestoides/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Helminto/genética , Modelos Genéticos , Anotação de Sequência Molecular , Tipagem de Sequências Multilocus , Filogenia , RNA de Helmintos/genética , RNA Ribossômico/genética
18.
J Helminthol ; 84(1): 107-14, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19646307

RESUMO

Schistosoma haematobium and S. bovis are widespread schistosome species causing human and cattle schistosomiasis, respectively, in Africa. The sympatric occurrence of these two species and their ability to infect the same Bulinus intermediate snail hosts necessitates precise methods of identification of the larval stages. A rapid diagnostic 'mulitplex' one-step polymerase chain reaction protocol (RD-PCR) was developed using cytochrome oxidase subunit 1 (COX1) mitochondrial DNA (mtDNA) to discriminate between S. haematobium and S. bovis. A single forward primer and two species-specific reverse primers were used to produce a polymerase chain reaction (PCR) fragment of 306 bp and 543 bp for S. bovis and S. haematobium, respectively. Serial dilutions were carried out on various lifecycle stages and species combinations to test the sensitivity and specificity of the primers. This RD-PCR proved highly sensitive, detecting a single larval stage and as little as 0.78 ng of genomic DNA (gDNA) from an adult schistosome, providing a cost-effective, rapid and robust molecular tool for high-throughput screening of S. haematobium and S. bovis populations. In areas where human and cattle schistosomiasis overlap and are transmitted in close proximity, this mitochondrial assay will be a valuable identification tool for epidemiological studies, especially when used in conjunction with other nuclear diagnostic markers.


Assuntos
Reação em Cadeia da Polimerase/métodos , Schistosoma/isolamento & purificação , Esquistossomose Urinária/parasitologia , Animais , Primers do DNA/genética , DNA de Helmintos/genética , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Helminto/genética , Humanos , Schistosoma/genética , Esquistossomose Urinária/diagnóstico
19.
Parasitology ; 136(13): 1813-24, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19627628

RESUMO

Representative samples of Ugandan Schistosoma mansoni from Lake Albert and Lake Victoria were examined using DNA barcoding, sequence analysis of two partially overlapping regions - ASMIT (396 bp) & MORGAN (617 bp) - of the mitochondrial cytochrome oxidase subunit I (cox1). The Victorian sample exhibited greater nucleotide diversity, 1.4% vs. 1.0%, and a significant population partition appeared as barcodes did not cross-over between lakes. With one exception, Lake Albert populations were more mixed by sampled location, while those from Lake Victoria appeared more secluded. Using statistical parsimony, barcode ASMIT 1 was putatively ancestral to all others and analysis of MORGAN cox1 confirmed population diversity. All samples fell into two of five well-resolved lineages; sub-lineages therein broadly partitioning by lake. It seems that barcode ASMIT 1 (and close variants) was likely widely dispersed throughout the Nilotic environment but later diversified in situ, and in parallel, within Lake Albert and Lake Victoria. The genetic uniformity of Ugandan S. mansoni can no longer be assumed, which might better explain known epidemiological heterogeneities. While it appears plausible that locally evolved heritable traits could spread through most of the Lake Albert populations, it seems unlikely they could quickly homogenise into Lake Victoria or amongst populations therein.


Assuntos
Variação Genética , Schistosoma mansoni/genética , Esquistossomose mansoni/epidemiologia , Esquistossomose mansoni/parasitologia , Animais , Sequência de Bases , Criança , Ciclo-Oxigenase 1/genética , DNA de Protozoário/genética , Água Doce , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Uganda/epidemiologia
20.
Plant Dis ; 93(4): 402-407, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30764224

RESUMO

Alternaria dauci and Cercospora carotae cause foliar blight on carrot, causing yield reductions in severely blighted fields. Currently, fungicides are used on either a 7-day schedule or according to the TOM-CAST disease forecasting system. Organic production prohibits applications of most fungicides for blight control but does allow select copper-based products. The objective of this study was to use the TOM-CAST weather forecasting system to (i) assess the efficacy of copper hydroxide treatments for organic operations and (ii) evaluate the efficacy of reduced-risk products in an alternating spray program. Chlorothalonil, azoxystrobin, and copper hydroxide were applied alone or in alternating programs in 2001 and 2002. Reapplications were made on a 7-day schedule or according to TOM-CAST using disease severity value (DSV) thresholds of 10, 15, and 20. Area under the disease progress curve (AUDPC) data revealed that all application intervals significantly limited disease incidence on the foliage and petioles, resulting in healthier petioles at harvest compared with the untreated. The 7-day and TOM-CAST 10 DSV programs had comparable rating values for all parameters assessed and were more effective than the TOM-CAST 15 and 20 DSV programs in limiting petiole disease and maintaining overall petiole health. Copper hydroxide treatments resulted in higher AUDPC values and significantly different petiole health ratings compared with other treatments, yet P values indicated significant disease control compared with the untreated. The TOM-CAST 15 DSV program reduced sprays up to 40% compared with a 7-day interval and produced mean savings of $127/ha in 2001 and $137/ha in 2002.

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