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1.
Phytopathology ; 112(7): 1406-1412, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35021858

RESUMO

'Candidatus Phytoplasma pruni' infection in cherries causes small, misshapen fruit with poor color and taste, rendering the fruit unmarketable. However, this is a disease with a long development cycle and a scattered, nonuniform symptom distribution in the early stages. To better understand the biology as well as the relationship between pathogen titer and disease expression, we carried out seasonal, spatial, and temporal examinations of 'Ca. P. pruni' titer and distribution in infected orchard-grown trees. Sequential sampling of heavily infected trees revealed marked seasonal patterns, with differential accumulation in woody stem and leaf tissues and, most notably, within fruit in the early stages of development from bloom to pit hardening. Furthermore, mapping phytoplasma distribution and titer in trees at different stages of infection indicated that infection proceeds through a series of stages. Initially, infection spreads basipetally and accumulates in the roots before populating aerial parts of the trees from the trunk upward, with infection of specific tissues and limbs followed by an increasing phytoplasma titer. Finally, we observed a correlation between phytoplasma titer and symptom severity, with severe symptom onset associated with three to four orders of magnitude more phytoplasma than mild symptoms. Cumulatively, these data aid in accurate sampling and management decision-making and furthers our understanding of disease development.


Assuntos
Phytoplasma , Prunus avium , Doenças das Plantas , Folhas de Planta , Árvores
2.
Surgeon ; 20(5): e288-e295, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35144899

RESUMO

BACKGROUND: Surgical resection, where appropriate, remains one of the best treatment options for hepatocellular carcinoma (HCC), however outcomes can be compromised by the development of liver failure. We reviewed our experience of liver resection for HCC patients to identify factors that may predict the development of post-hepatectomy liver failure (PHLF) and survival. METHODS: A single centre retrospective cohort study. Data was collected between 1999 and 2017 from all patients undergoing HCC resection in a tertiary university hospital from electronic medical records. PHLF was defined as per the International Study Group for Liver Surgery criteria. Variables with p < 0.15 on univariate analysis were included in a multivariate binary logistic regression model. Kaplan-Meier analyses were used to determine correlations with overall survival (OS) and disease-free survival (DFS), and variables with p < 0.15 on univariate analysis selected for a step-down Cox proportional hazard regression model. RESULTS: Overall, 120 patients underwent liver resection within the study period, of which 22 (18%) developed PHLF. Patients with normal INR ≤1.20 at day 2 did not develop PHLF whereas patients with INR >1.60 were at significant risk. Resection of multiple tumours (odds ratio 21.63, p = 0.002) and deranged postoperative day 2 INR>1.6 (odds ratio 21.05, p < 0.0001) were identified as independent prognostic markers of PHLF. CONCLUSION: The use of INR measurement at day 2 predicts PHLF and may enable us to objectively identify and stratify patients who may be eligible for enhanced recovery programs from those who will merit close monitoring in high dependency areas.


Assuntos
Carcinoma Hepatocelular , Falência Hepática , Neoplasias Hepáticas , Hepatectomia/efeitos adversos , Humanos , Coeficiente Internacional Normatizado , Falência Hepática/etiologia , Falência Hepática/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos
3.
Plant Dis ; 105(1): 14-26, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32840434

RESUMO

Pathogen-tested foundation plant stocks are the cornerstone of sustainable specialty crop production. They provide the propagative units that are used to produce clean planting materials, which are essential as the first-line management option of diseases caused by graft-transmissible pathogens such as viruses, viroids, bacteria, and phytoplasmas. In the United States, efforts to produce, maintain, and distribute pathogen-tested propagative material of specialty crops are spearheaded by centers of the National Clean Plant Network (NCPN). Agricultural economists collaborated with plant pathologists, extension educators, specialty crop growers, and regulators to investigate the impacts of select diseases caused by graft-transmissible pathogens and to estimate the return on investments in NCPN centers. Economic studies have proven valuable to the NCPN in (i) incentivizing the use of clean planting material derived from pathogen-tested foundation plant stocks; (ii) documenting benefits of clean plant centers, which can outweigh operating costs by 10:1 to 150:1; (iii) aiding the development of disease management solutions that are not only ecologically driven but also profit maximizing; and (iv) disseminating integrated disease management recommendations that resonate with growers. Together, economic studies have reinforced efforts to safeguard specialty crops in the United States through the production and use of clean planting material.


Assuntos
Agricultura , Produtos Agrícolas , Estados Unidos
4.
Pancreatology ; 19(7): 1000-1007, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31445889

RESUMO

BACKGROUND: Non-functional pancreatic neuroendocrine tumours (NF-PNETs) are rare and have highly variable outcomes. Current guidelines recommend surveillance for NF-PNETs <2 cm. Patients who ultimately have surgical resection are at risk of disease recurrence, and data to support postoperative surveillance protocols are lacking. The aims of this study were to i) identify post-operative predictors of recurrence and ii) risk stratify patients at risk of recurrence. METHODS: Consecutive patients who underwent surgery for NF-PNETs between 2002 and 2015 were identified retrospectively. Data were collected on demographics, pre-operative laboratory results and histopathological tumour characteristics. Statistical analyses were based on penalised Cox-regression modelling and a decision-tree model. Comparison of the variables identified was performed using ROC curves to identify the most sensitive and specific variable associated with disease recurrence. RESULTS: We identified 73 patients (38 males) with a median age of 61.5 years (range: 31-79). The median period of follow-up was 49 months (5-131). During follow up, 10 deaths (13.9%) were recorded and disease recurrence occurred in 12 patients (16.4%). The Kaplan-Meier predicted 1-,3- and 5-year recurrence-free survival rates were 98.6% (95% CI = 95.9, 100%), 85.4% (76.9-94.8%) and 72% (58.7-88.2%) respectively. Cox multivariate analysis identified poor tumour differentiation (WHO G3 grade) and lymph node ratio (LNR) as independent predictors for recurrence (p < 0.05). A simple criterion of 'tumour grade G3 or LNR ≥0.1' was found to be sensitive and specific in detecting disease recurrence. CONCLUSION: Our results have identified a simple and sensitive criterion for risk stratifying post-resection surveillance. Prospective validation in larger patient cohort is now warranted.


Assuntos
Metástase Linfática , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Cuidados Pós-Operatórios , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Tumores Neuroendócrinos/cirurgia , Razão de Chances , Neoplasias Pancreáticas/cirurgia , Estudos Retrospectivos
5.
Arch Virol ; 163(12): 3373-3376, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30191371

RESUMO

Aphid transmission is a major factor in the formation of citrus tristeza virus (CTV) populations. Here, we examined the effect of population interaction on aphid transmissibility of different CTV genotypes. We found that there was no correlation between the proportion of viral genotypes in the source population and what was transmitted. We next examined the transmission of a poorly transmitted infectious cDNA clone (T36) in mixture with other CTV genotypes. T36 transmission increased from 0.5% alone, to up to 35.7%, depending on the coinfecting genotype. These results suggest that interaction between CTV genotypes affects the transmission of this virus.


Assuntos
Citrus/virologia , Closterovirus/genética , Doenças das Plantas/virologia , Animais , Afídeos/fisiologia , Afídeos/virologia , Closterovirus/classificação , Closterovirus/isolamento & purificação , Closterovirus/fisiologia , Genótipo , Insetos Vetores/fisiologia , Insetos Vetores/virologia
6.
Arch Virol ; 163(12): 3339-3343, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30132135

RESUMO

High-throughput sequencing of two trees with apple decline revealed the presence of three bunya-like viruses: apple rubbery wood-associated viruses 1 and 2 (ARWaV-1, ARWaV-2) and citrus concave gum-associated virus (CCGaV), which previously had only been observed in citrus trees. The apple and citrus CCGaV isolates shared over 97% sequence identity. A global collection of apple trees was screened by RT-PCR for these viruses. Twenty-seven of 30 trees were infected with one or more bunya-like virus. Sequence data revealed some diversity among isolates but no geographic grouping. Additional work will be needed to determine if any of these viruses contribute to apple decline.


Assuntos
Malus/virologia , Doenças das Plantas/virologia , Vírus de Plantas/genética , Citrus/virologia , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Vírus de Plantas/classificação , Vírus de Plantas/isolamento & purificação , RNA Viral/genética
7.
Appl Environ Microbiol ; 82(21): 6294-6302, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27520823

RESUMO

Vector transmission is a critical stage in the viral life cycle, yet for most plant viruses how they interact with their vector is unknown or is explained by analogy with previously described relatives. Here we examined the mechanism underlying the transmission of citrus tristeza virus (CTV) by its aphid vector, Toxoptera citricida, with the objective of identifying what virus-encoded proteins it uses to interact with the vector. Using fluorescently labeled virions, we demonstrated that CTV binds specifically to the lining of the cibarium of the aphid. Through in vitro competitive binding assays between fluorescent virions and free viral proteins, we determined that the minor coat protein is involved in vector interaction. We also found that the presence of two heat shock-like proteins, p61 and p65, reduces virion binding in vitro Additionally, treating the dissected mouthparts with proteases did not affect the binding of CTV virions. In contrast, chitinase treatment reduced CTV binding to the foregut. Finally, competition with glucose, N-acetyl-ß-d-glucosamine, chitobiose, and chitotriose reduced the binding. These findings together suggest that CTV binds to the sugar moieties of the cuticular surface of the aphid cibarium, and the binding involves the concerted activity of three virus-encoded proteins. IMPORTANCE: Limited information is known about the specific interactions between citrus tristeza virus and its aphid vectors. These interactions are important for the process of successful transmission. In this study, we localized the CTV retention site as the cibarium of the aphid foregut. Moreover, we demonstrated that the nature of these interactions is protein-carbohydrate binding. The viral proteins, including the minor coat protein and two heat shock proteins, bind to sugar moieties on the surface of the foregut. These findings will help in understanding the transmission mechanism of CTV by the aphid vector and may help in developing control strategies which interfere with the CTV binding to its insect vector to block the transmission.


Assuntos
Afídeos/virologia , Proteínas do Capsídeo/metabolismo , Closterovirus/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas Virais/metabolismo , Ligação Viral , Animais , Afídeos/anatomia & histologia , Afídeos/metabolismo , Citrus/virologia , Closterovirus/química , Sistema Digestório/virologia , Insetos Vetores/virologia , Microscopia de Polarização , Doenças das Plantas/virologia , Vírion/metabolismo , Vírion/ultraestrutura
8.
Arch Virol ; 161(12): 3567-3570, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27659675

RESUMO

Viruses often infect plants as a mixed population. The dynamics of viral populations dictate the success of the infection, yet there is little understanding of the factors that influence them. It is known that temperature can affect individual viruses; could it also affect a virus population? In order to study this, we observed citrus tristeza virus (CTV) populations in different hosts under winter and summer conditions (25 versus 36 °C). We found that only some CTV strains were affected by a higher summer temperature, which lead to a change in CTV population structure, and that this effect was host dependent.


Assuntos
Closterovirus/fisiologia , Closterovirus/efeitos da radiação , Doenças das Plantas/virologia , Plantas/virologia , Temperatura , Interações Hospedeiro-Patógeno , Estações do Ano
9.
Arch Virol ; 161(12): 3555-3559, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27644950

RESUMO

Vector transmission is an important part of the viral infection cycle, yet for many viruses little is known about this process, or how viral sequence variation affects transmission efficacy. Here we examined the effect of substituting genes from the highly transmissible FS577 isolate of citrus tristeza virus (CTV) in to the poorly transmissible T36-based infectious clone. We found that introducing p65 or p61 sequences from FS577 significantly increased transmission efficacy. Interestingly, replacement of both genes produced a greater increase than either gene alone, suggesting that CTV transmission requires the concerted action of co-evolved p65 and p61 proteins.


Assuntos
Afídeos/virologia , Citrus/virologia , Closterovirus/genética , Insetos Vetores , Doenças das Plantas/virologia , Proteínas Virais/genética , Animais , Variação Genética
10.
Am J Transplant ; 15(6): 1459-71, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25981150

RESUMO

Variant anatomy may be challenging at retrieval, with failure to identify variance being associated with organ damage, particularly vascular damage. On implantation, some variants demand nonstandard techniques of reconstruction or implantation. This review covers the common and less common anatomical variants of the liver, kidney and pancreas, and gives guidance as to how they may be managed during organ retrieval and implantation.


Assuntos
Rim/anatomia & histologia , Fígado/anatomia & histologia , Transplante de Órgãos/métodos , Pâncreas/anatomia & histologia , Humanos , Rim/anormalidades , Rim/irrigação sanguínea , Transplante de Rim/métodos , Fígado/anormalidades , Fígado/irrigação sanguínea , Transplante de Fígado/métodos , Pâncreas/anormalidades , Pâncreas/irrigação sanguínea , Transplante de Pâncreas/métodos , Coleta de Tecidos e Órgãos/tendências
11.
Clin Radiol ; 70(11): 1220-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26194860

RESUMO

AIM: To examine the usage and value of computed tomography (CT) following simultaneous pancreas and kidney (SPK) transplantation. MATERIALS AND METHODS: Indications for postoperative CT, key findings, and their influence on management were determined by retrospective analysis. RESULTS: Ninety-eight patients underwent 313 CT examinations. Common indications for the examinations included suspected intra-abdominal collection (31.1%) and elevated serum amylase/lipase (24.1%). CT findings most frequently showed non-specific mild inflammation (27.6%), a normal scan (17.1%) and fluid collections (16.3%). High capillary blood glucose (CBG) was associated with resultant CT demonstration of graft vascular abnormalities, but otherwise, particular clinical indications were not associated with specific CT findings. CONCLUSION: Clinical findings in patients with SPK transplants are non-specific. The pattern of abnormalities encountered is significantly different to those seen in native pancreatic disease and demands a tailored protocol. CT enables accurate depiction of vascular abnormalities and fluid collections, thus reducing the number of surgical interventions that might otherwise be required. Elevated CBG should prompt urgent CT to exclude potentially reversible vascular complications.


Assuntos
Transplante de Pâncreas/métodos , Pâncreas/diagnóstico por imagem , Adulto , Aloenxertos/diagnóstico por imagem , Glicemia/metabolismo , Feminino , Sobrevivência de Enxerto , Humanos , Estimativa de Kaplan-Meier , Transplante de Rim/métodos , Masculino , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Transplante Homólogo/métodos
12.
Neurobiol Dis ; 71: 245-59, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25151644

RESUMO

Vascular endothelial growth factor-A (VEGF-A) is best known as a key regulator of the formation of new blood vessels. Neutralization of VEGF-A with anti-VEGF therapy e.g. bevacizumab, can be painful, and this is hypothesized to result from a loss of VEGF-A-mediated neuroprotection. The multiple vegf-a gene products consist of two alternatively spliced families, typified by VEGF-A165a and VEGF-A165b (both contain 165 amino acids), both of which are neuroprotective. Under pathological conditions, such as in inflammation and cancer, the pro-angiogenic VEGF-A165a is upregulated and predominates over the VEGF-A165b isoform. We show here that in rats and mice VEGF-A165a and VEGF-A165b have opposing effects on pain, and that blocking the proximal splicing event - leading to the preferential expression of VEGF-A165b over VEGF165a - prevents pain in vivo. VEGF-A165a sensitizes peripheral nociceptive neurons through actions on VEGFR2 and a TRPV1-dependent mechanism, thus enhancing nociceptive signaling. VEGF-A165b blocks the effect of VEGF-A165a. After nerve injury, the endogenous balance of VEGF-A isoforms switches to greater expression of VEGF-Axxxa compared to VEGF-Axxxb, through an SRPK1-dependent pre-mRNA splicing mechanism. Pharmacological inhibition of SRPK1 after traumatic nerve injury selectively reduced VEGF-Axxxa expression and reversed associated neuropathic pain. Exogenous VEGF-A165b also ameliorated neuropathic pain. We conclude that the relative levels of alternatively spliced VEGF-A isoforms are critical for pain modulation under both normal conditions and in sensory neuropathy. Altering VEGF-Axxxa/VEGF-Axxxb balance by targeting alternative RNA splicing may be a new analgesic strategy.


Assuntos
Anticorpos/uso terapêutico , DNA Recombinante/genética , Neuralgia/metabolismo , Neuralgia/terapia , RNA Mensageiro/metabolismo , Fator A de Crescimento do Endotélio Vascular , Animais , Anticorpos/farmacologia , Benzofuranos , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Gânglios Espinais/citologia , Hiperalgesia/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Condução Nervosa/genética , Medição da Dor , Limiar da Dor/fisiologia , Quinolinas , RNA Mensageiro/genética , Ratos , Ratos Wistar , Células Receptoras Sensoriais/efeitos dos fármacos , Células Receptoras Sensoriais/metabolismo , Canais de Cátion TRPV/deficiência , Canais de Cátion TRPV/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Reproduction ; 143(4): 501-11, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22232745

RESUMO

Angiogenesis and vascular regression are critical for the female ovulatory cycle. They enable progression and regression of follicular development, and corpora lutea formation and regression. Angiogenesis in the ovary occurs under the control of the vascular endothelial growth factor-A (VEGFA) family of proteins, which are generated as both pro-(VEGF(165)) and anti(VEGF(165)b)-angiogenic isoforms by alternative splicing. To determine the role of the VEGF(165)b isoforms in the ovulatory cycle, we measured VEGF(165)b expression in marmoset ovaries by immunohistochemistry and ELISA, and used transgenic mice over-expressing VEGF(165)b in the ovary. VEGF(165)b was expressed in the marmoset ovaries in granulosa cells and theca, and the balance of VEGF(165)b:VEGF(165) was regulated during luteogenesis. Mice over-expressing VEGF(165)b in the ovary were less fertile than wild-type littermates, had reduced secondary and tertiary follicles after mating, increased atretic follicles, fewer corpora lutea and generated fewer embryos in the oviduct after mating, and these were more likely not to retain the corona radiata. These results indicate that the balance of VEGFA isoforms controls follicle progression and luteogenesis, and that control of isoform expression may regulate fertility in mammals, including in primates.


Assuntos
Fertilidade , Ovário/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Callithrix , Regulação para Baixo , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Ovário/crescimento & desenvolvimento , Gravidez
14.
J Virol Methods ; 300: 114395, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34861319

RESUMO

Viroids present a number of issues for their detection and diagnosis because of the absence of symptom expression in many hosts and their low titers in infected plants. However, quarantine programs rely on symptom observations and routine diagnostic testing to reduce the risk of spreading viroid-infected materials to situations where they might affect crop health and production. Sensitive, accurate, and specific assays for viroid detection from both asymptomatic and symptomatic hosts are necessary for managing viroids in post-entry quarantine and certification schemes. The aim of this study was to develop and optimize superior assays based on the reverse-transcription quantitative polymerase chain reaction (RT-qPCR) for the specific detection of apple hammerhead viroid (AHVd), apple scar skin viroid (ASSVd) and pear blister canker viroid (PBCVd). The real-time RT-qPCR assays thus developed detected a greater range of viroid isolates and with greater sensitivity than the current endpoint RT-PCR assays, down to 101 copies per reaction without any amplification of the non-target viroid or virus sequences tested.


Assuntos
Malus , Pyrus , Viroides , Doenças das Plantas , Reação em Cadeia da Polimerase em Tempo Real , Viroides/genética
15.
BJOG ; 118(10): 1253-61, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21668772

RESUMO

OBJECTIVE: Pre-eclampsia is diagnosed by hypertension and proteinuria, probably caused by endothelial dysfunction, resulting in symptoms including oedema, inflammation and altered metabolism. Vascular endothelial growth factor A (VEGF-A) is detected at higher concentrations in plasma from patients with pre-eclampsia than in plasma from normotensive pregnant patients when determined by radioimmunoassay. This study tested the hypothesis that circulating VEGF-A in pre-eclamptic plasma is biologically active in vivo, and aimed to identify specific isoforms responsible for this activity. DESIGN: Plasma from pre-eclamptic (n = 17) and normotensive (n = 10) pregnant women was perfused into Rana mesenteric microvessels, and the subsequent change in microvascular permeability was measured using a single-vessel perfusion micro-occlusion technique. RESULTS: Pre-eclamptic but not normotensive plasma resulted in a 5.25 ± 0.8-fold acute increase in vascular permeability (P = 0.0003). This increase could be blocked by the incubation of plasma with bevacizumab, an antibody to VEGF-A (n = 7; P = 0012), and by VEGF-A receptor inhibition by SU5416 at doses specific to VEGF-A receptor-1 (VEGFR1), but not by the VEGF-A receptor-2 inhibitor, ZM323881. Although VEGF(165) b levels were not significantly altered in the PET samples, the increase in permeability was also inhibited by incubation of pre-eclamptic plasma with an inhibitory monoclonal antibody specific for VEGF165b (n=6; P<0.01), or by the addition of placental growth factor 1 (PlGF-1; n = 3; P < 0.001). PlGF-1 was detected at lower concentrations in pre-eclamptic plasma than in normotensive plasma. CONCLUSIONS: These findings suggest that circulating VEGF-A levels in pre-eclampsia are biologically active because of a loss of repression of VEGFR1 signalling by PlGF-1, and VEGF165b may be involved in the increased vascular permeability of pre-eclampsia.


Assuntos
Permeabilidade Capilar/fisiologia , Pré-Eclâmpsia/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Bevacizumab , Bioensaio , Feminino , Humanos , Proteínas de Membrana/sangue , Gravidez , Quinazolinas/farmacologia , Ranidae , Fator A de Crescimento do Endotélio Vascular/imunologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores
16.
Plant Dis ; 95(6): 775, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30731925

RESUMO

In December 2008, a collection of Citrus spp. in Kerikeri, New Zealand was surveyed for virus and viroid diseases. Symptoms characteristic of virus or viroid infection were not observed other than Citrus tristeza virus (CTV)-associated stem pitting when examined with the bark removed. Total RNA was extracted from bark samples of 273 trees using RLT buffer (Qiagen Inc., Chatsworth, CA) on a KingFisher mL workstation (Thermo Scientific, Waltham, MA) and tested by reverse transcription (RT)-PCR). Samples from three trees, two from sweet orange, Citrus × sinensis (L.) Osbeck (pro sp.) (maxima × reticulate) and one from tangerine, Citrus reticulata Blanco, tested positive for Citrus psorosis virus (CPsV), and two samples, one each from lemon, Citrus × limon (L.) Burm. F. (pro sp.) (medica × aurantifolia) and sweet orange, tested positive for Citrus viroid III (CVd-III) using previously published primers and PCR cycling conditions (2,4) in a one-step RT-PCR system. The 20-µl RT-PCR reaction was done with Verso Reddymix reagents (Thermo Scientific) containing 250 nM of specific primers and 300 µg/µl of bovine serum albumin (Sigma-Aldrich, St. Louis, MO). The CVd-III genome was completed using specific internal primers (forward: 5'-AACGCAGAGAGGGAAAGGGAA-3', reverse: 5'-TAGGGCTACTTCCCGTGGTC-3') with the following cycling conditions: 50°C for 15 min, 94°C for 2 min, then 40 cycles of 94°C for 10 s, 57°C for 30 s, and 68°C for 30 s. The three CPsV amplicons of 419 bp from the RNA-dependent RNA polymerase gene (GenBank Accession Nos. GQ388241 to GQ388243) had 96 to 100% nucleotide identity to each other. A 276-bp (nt position 48 to 323) fragment of the 419-bp sequence was used for comparison with sequences available on GenBank. The three 276-bp CPsV sequences had 89 to 97% nucleotide identity to other CPsV available in GenBank at the time of the analysis. The CVd-III genomes of 291 bp (GenBank Accession Nos. HQ219183 and JF521494) are identical and showed 94 to 99% nucleotide identity to other CVd-III available in GenBank. The presence of CPsV was confirmed in the three samples by a CPsV-specific double-antibody sandwich-ELISA kit (Agritest S.r.l., Valenzano, Italy), while the presence of CVd-III was confirmed only in the lemon sample by r-PAGE (3). The concentration of the viroid in the sweet orange sample may have been below the detection limit of the test. The incidence of the diseases is probably low since CPsV and CVd-III were detected in only a few trees which were planted between 1998 and 2002 at Kerikeri from budwoods of unknown sources imported between the 1970s and 1990s. New Zealand's growing conditions generally do not favor viroid replication in plants, whereas the temperatures may be suitable for CPsV disease. However, symptom characteristics to CPsV and CVd-III have never been observed on the infected trees. This is most likely because of the presence of CTV in the trees (data not shown). CPsV symptoms were thought to have been observed in the 1950s in New Zealand (1) but the causal agent had not been identified. To our knowledge, this is the first molecular and serological evidence of CPsV and the first report of the presence of CVd-III in New Zealand. References: (1) W. A. Fletcher. Orchard. N. Z. 30:33, 1957. (2) T. Ito et al. J. Virol. Methods 106:235, 2002. (3) C. Jeffries and C. James. OEPP/EPPO Bull. 35:125, 2005. (4) S. Martin et al. J. Gen. Virol. 87:3097, 2006.

17.
Plant Dis ; 95(5): 617, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-30731974

RESUMO

In February 2009, grapevines (Vitis vinifera) in a commercial vineyard in Auckland were showing shortened, spindly canes with tiny leaves. Approximately 10% of the vines were affected. An RNeasy Plant Mini Kit (Qiagen, Valencia, CA) was used to isolate total RNA from leaves collected from six symptomatic (cvs. BAC0022A and Syrah) and eight symptomless vines (cvs. BAC0022A, Syrah, and Chardonnay). RNA was tested by reverse transcription-PCR for the presence of Australian grapevine viroid, Citrus exocortis viroid, Grapevine yellow speckle viroid 1 (GYSVd-1), Grapevine yellow speckle viroid 2, and Hop stunt viroid (HSVd). Four of the six symptomatic and all the symptomless vines tested positive for GYSVd-1 using primers 5'-TGTGGTTCCTGTGGTTTCAC-3' and 5'-ACCACAAGCAAGAAGATCCG-3', which amplify the complete genome (368 bp), and published primers PBCVd100C/194H (3), which amplify a 220-bp region of the genome. Amplicons from each PCR were transformed into a pCR 4-TOPO vector (Invitrogen, Carlsbad, CA), cloned, and sequenced. Sequence from both PCRs aligned identically to generate a consensus sequence (GenBank Accession No. HQ447056), which showed 99% nt identity to GYSVd-1 (GenBank No. X87906) by BLASTN analysis. All symptomatic and symptomless vines also tested positive for HSVd using primers C/H-HSVd (4) and HSVd-C60/H79 (1), which amplify the complete genome (298 bp). Amplicons from each isolate were cloned and sequenced. Sequence from both PCRs were aligned. Clones from all isolates, with the exception of one, aligned identically to create a consensus sequence (GenBank No. HQ447057) that showed 99% nt identity to Chinese HSVd isolates from grapevine (GenBank Nos. DQ371436-59) by BLASTN analysis. Sequence from the remaining isolate (GenBank No. HQ447056) was identical to a German Riesling grape isolate of HSVd (GenBank No. X06873). The presence of each viroid was further confirmed in PCR-positive plants by dot-blot hybridization with digoxigenin-labeled synthetic ssRNA probes specific to the full-length genomes of GYSVd-1 and HSVd (S. Harper and L. Ward, unpublished data). To our knowledge, this is the first report of GYSVd-1 and HSVd in V. vinifera in New Zealand. Since both viroids were detected in symptomatic and symptomless plants, the symptoms observed in the vineyard cannot be attributed to viroid infection. Symptoms described for GYSVd-1 include leaf spots and flecks, but no disease symptoms have been reported in grapes as a result of HSVd (2). Viruses found in the vines include Grapevine leaf roll virus-3, Grapevine viruses A and B, and Rupestris stem pitting associated virus, but these are not thought to be the cause of the symptoms. Two sequence types of HSVd were found, suggesting at least two separate introductions of HSVd into the vineyard. The vineyard is more than 40 years old so both viroids may have been present for some years. Export of wine from New Zealand was worth 1 billion dollars in 2009, so there is potential for these viroids to have an economic impact if symptoms are expressed. HSVd has been reported from China, Europe, Japan, Middle East, Pakistan, and the United States. GYSVd-1 has been reported from Australia, China, East Mediterranean, Europe, Japan, and the United States. References: (1) A. Hadidi et al. Acta Hortic. 309:339, 1992. (2) A. Hadidi et al., eds. Viroids. CSIRO Publishing, Collingwood, Australia, 2003. (3) R. Nakaune and M. Nakano. J. Virol. Methods 134:244, 2006. (4) A. M. Shamoul et al. J. Virol. Methods 105:115, 2002.

18.
J Virol Methods ; 292: 114124, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33711375

RESUMO

American hop latent virus (AHLV), hop latent virus (HLV) and hop mosaic virus (HMV) infect members of the Humulus genus worldwide, but very little is known of the biology and etiology of these viruses. A better understanding of these viruses from the molecular level to their economic impact relies on efficient diagnostic assays. Therefore, in this study we developed reverse transcription quantitative polymerase chain reaction (RT-qPCR) assays for the detection of AHLV, HLV, and HMV through an alignment of representative sequences from the National Center for Biotechnology Information (NCBI) database. These assays demonstrated unambiguously their high sensitivity by detecting the respective targets from as low as 102 copies of transcripts per reaction without any amplification from non-targets.


Assuntos
Carlavirus , Humulus , Vírus do Mosaico , Carlavirus/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Br J Surg ; 97(1): 21-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19937983

RESUMO

BACKGROUND: This randomized controlled trial was designed to determine the safety and efficacy of laparoscopic donor nephrectomy (LDN) in comparison with short-incision open donor nephrectomy (ODN). METHODS: Eighty-four live kidney donors were randomized in a 2 : 1 ratio to LDN (56 patients) or short-incision ODN without rib resection (28). Primary endpoints were pain relief and duration of inpatient stay. RESULTS: There was no donor death or allograft thrombosis in either group. The first warm ischaemic time median (range) 4 (2-7) versus 2 (1-5) min; P = 0.001) and the duration of operation (160 (110-250) versus 150 (90-200); P = 0.004) were longer for LDN. LDN led to a reduction in parenteral morphine requirement 59 (6-136) versus 90 (35-312) mg; P = 0.001) and hospital stay (4 (2-6) versus 6 (2-9) days; P = 0.001), and earlier return to employment (42 (14-84) versus 66.5 (14-112) days; P = 0.004). Postoperative respiratory function was improved after LDN. There were more postoperative complications per donor in the ODN group (0.6(0.7) versus 0.3(0.5); P = 0.033). At a median follow-up of 74 months, there were no differences in renal function or allograft survival between the groups. CONCLUSION: LDN removes some of the disincentives to live donation without compromising the outcome of the recipient transplant.


Assuntos
Transplante de Rim/métodos , Laparoscopia/métodos , Doadores Vivos , Nefrectomia/métodos , Coleta de Tecidos e Órgãos/métodos , Analgésicos Opioides/uso terapêutico , Feminino , Humanos , Complicações Intraoperatórias/etiologia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Morfina/uso terapêutico , Dor Pós-Operatória/prevenção & controle , Complicações Pós-Operatórias/etiologia , Prognóstico , Testes de Função Respiratória
20.
Arch Virol ; 155(4): 471-80, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20352212

RESUMO

The economically important rootstock species Poncirus trifoliata is resistant to most isolates of Citrus tristeza virus (CTV), but not to members of the CTV resistance-breaking (RB) strain presently found in New Zealand. In this study, five known and suspected RB isolates were separated from field mixtures, and their genomes were sequenced in full. It was found that the RB isolates are members of a single phylogenetically distinct clade with an average of 90.3% genomic nucleotide sequence identity to the closest extant isolate, T36. These isolates also show evidence of multiple recombination events throughout their evolutionary history, with T36, T30 and VT-like isolates, and with each other. Finally, the genomic sequences of these isolates show that several genes contain unique polymorphisms that may or may not be involved in overcoming resistance. These data will aid in the understanding of host-virus interactions, and the mechanism of resistance in P. trifoliata.


Assuntos
Closterovirus/classificação , Closterovirus/isolamento & purificação , Genoma Viral , Poncirus/virologia , RNA Viral/genética , Closterovirus/genética , Closterovirus/crescimento & desenvolvimento , Análise por Conglomerados , Evolução Molecular , Dados de Sequência Molecular , Nova Zelândia , Filogenia , Polimorfismo Genético , Recombinação Genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
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