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1.
Funct Plant Biol ; 42(8): 792-801, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32480722

RESUMO

In addition to producing medicinally important tropane alkaloids, some species in the mainly Australian Solanaceous tribe Anthocercideae, sister to genus Nicotiana, are known to also contain substantial levels of the pyridine alkaloids nicotine and nornicotine. Here, we demonstrate that axenic hairy root cultures of two tribe Anthocercideae species, Cyphanthera tasmanica Miers and Anthocercis ilicifolia ssp. ilicifolia Hook, contain considerable amounts of both nicotine and nornicotine (~0.5-1% DW), together with lower levels of the tropane alkaloid hyoscyamine (<0.2% DW). Treatment of growing hairy roots of both species with micromolar levels of the wound stress hormone methyl-jasmonate (MeJa) led to significant increases (P<0.05) in pyridine alkaloid concentrations but not of hyoscyamine. Consistent with previous studies involving Nicotiana species, we also observed that transcript levels of key genes required for pyridine alkaloid synthesis increased in hairy roots of both Anthocercideae species following MeJa treatment. We hypothesise that wound-associated induction of pyridine alkaloid synthesis in extant species of tribe Anthocercideae and genus Nicotiana was a feature of common ancestral stock that existed before the separation of both lineages ~15million years ago.

3.
J Clin Imaging Sci ; 3: 22, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23814694

RESUMO

The von Meyenburg complex (VMC) is an uncommon congenital malformation and is characterized by benign bile duct hamartomas. These are usually discovered incidentally and may represent a diagnostic dilemma when liver metastases are suspected. MRI of VMC shows distinct imaging characteristics, but reporting of lesional contrast enhancement has been inconsistent, whilst microbubble contrast enhanced ultrasound provides 'real-time' evaluation of soft tissue vascularity. Given the diagnostic uncertainty over imaging in VMC, biopsy is often recommended as the definitive diagnosis. We report a biopsy proven case of VMC on a background of primary colonic malignancy investigated with ultrasound, contrast enhanced ultrasound, computed tomography CT, and magnetic resonance imaging MRI, and review the key imaging features.

4.
Phytochemistry ; 86: 21-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23177980

RESUMO

Unlike most Nicotiana species, leaf tissues of the globally significant weed Nicotiana glauca Grah. (Argentinian tree tobacco) contains anabasine as the main component of its alkaloid pool, with concentrations typically increasing several fold in response to wounding of plants. The Δ(1)-piperidinium ring of anabasine is synthesised from cadaverine, via the decarboxylation of lysine, however the identity of the protein catalysing this reaction remains unknown. Recent studies indicate that ornithine decarboxylase (ODC), an enzyme involved in the synthesis of the diamine putrescine, may also possess LDC activity. Previously we found that ODC transcript is markedly up-regulated in leaves of N. glauca in response to wounding. In order to examine the role of ODC in the synthesis of anabasine in N. glauca, transcript levels were constitutively down-regulated in hairy root cultures and transgenic plants via the introduction of a CaMV35S driven ODC-RNAi construct. In addition to the anticipated marked reduction in nicotine concentrations, demonstrating that the ODC-RNAi construct was functioning in vivo, we observed that N. glauca ODC-RNAi hairy root cultures had a significantly diminished capacity to elevate anabasine synthesis in response to treatment with the wound-associated hormone methyl jasmonate, when compared to vector-only controls. We observed also that ODC-RNAi transgenic plants had significantly reduced ability to increase anabasine concentrations following removal of the plant apex. We conclude that ODC does have an important role in enabling N. glauca to elevate levels of anabasine in response to wound-associated stress.


Assuntos
Anabasina/metabolismo , Nicotiana/enzimologia , Nicotiana/metabolismo , Ornitina Descarboxilase/metabolismo , Ornitina Descarboxilase/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/enzimologia , Raízes de Plantas/metabolismo , Interferência de RNA
5.
Meat Sci ; 84(1): 165-71, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20374770

RESUMO

Relationships between Japanese color score (JCS) and pork quality attributes were studied and three equations were developed to predict JCS. Averages for population one (n=781) traits were used to develop initial prediction equations and traits from population two (n=684) were used to evaluate the success of the prediction equations. The first equation was: JCS=12.698-(0.01128 x firmness)+(0.09008 x pH)-(0.00007199 x drip loss)-(0.266 x L*)+(0.06923 x a*)-(0.201 x b*)+(0.02143 x hue angle); r(2)=0.916. The second equation was: JCS=15.255-(0.259 x L*)-(0.213 x b*)+(0.02518 x hue angle); r(2)=0.931. The third equation was: JCS=12.920-(0.219 x L*)+(0.07342 x a*)-(0.02166 x b*); r(2)=0.906. All equations predicted 92% or more Japanese color scores within +/-0.50. Requiring fewer measurements, the second and third equations would be advantageous when sorting pork on the basis of JCS.


Assuntos
Indústria de Embalagem de Carne/métodos , Carne/normas , Modelos Biológicos , Pigmentação , Tecido Adiposo Branco/anatomia & histologia , Animais , Composição Corporal , Peso Corporal , Fenômenos Químicos , Gorduras na Dieta/análise , Humanos , Concentração de Íons de Hidrogênio , Japão , Carne/análise , Carne/economia , Indústria de Embalagem de Carne/economia , Controle de Qualidade , Análise de Regressão , Propriedades de Superfície , Sus scrofa , Tato , Água/análise
6.
Eur J Ultrasound ; 15(1-2): 37-43, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12044851

RESUMO

Hepatic artery thrombosis after liver transplant is associated with biliary sepsis and irretrievable loss of the graft. Early identification of hepatic artery thrombosis, using a 'high-specification' ultrasound machine incorporating spectral Doppler, is crucial to patient management in the postoperative period with portable ultrasound as the first line of investigation for evaluation of the hepatic artery. We evaluated the efficacy of the SonoSite portable ultrasound machine, which uses power Doppler only, in the evaluation of the post transplant hepatic artery. An Acuson 128/XP10 ultrasound machine was used as the comparison 'reference-standard' with identification of the hepatic artery by both colour and spectral Doppler trace. The SonoSite accurately identified the hepatic artery in 88.4% of patients with power Doppler. The SonoSite was easier to transport and manage at the bedside leading to considerable time saving. In 11.6% of patients a repeat ultrasound using the 'reference-standard' machine would be necessary.


Assuntos
Artéria Hepática/diagnóstico por imagem , Transplante de Fígado/diagnóstico por imagem , Sistemas Automatizados de Assistência Junto ao Leito , Complicações Pós-Operatórias/diagnóstico por imagem , Trombose/diagnóstico por imagem , Ultrassonografia/instrumentação , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade
7.
Eur Radiol ; 14(1): 21-30, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14530998

RESUMO

We prospectively evaluated the role of microbubble ultrasound contrast for detection of hepatic artery thrombosis following liver transplantation. The hepatic artery of adult liver transplant recipients with suspected thrombosis on surveillance Doppler ultrasound (US) were re-examined by a second observer. In patients with no hepatic spectral Doppler signal the microbubble contrast agent Levovist was used. The presence or absence of flow following microbubble contrast was evaluated against arteriography or repeated Doppler US findings. A total of 794 surveillance Doppler US examinations were performed in 231 patients. Hepatic artery flow was demonstrated in 759 of 794 (95.6%) examinations. Microbubble ultrasound contrast was administered in 31 patients (35 studies) with suspected hepatic artery thrombosis. Following microbubble US contrast the hepatic artery could not be demonstrated in 13 of 35 (37.1%) studies (12 patients). Eight patients had arteriography: there was hepatic artery thrombosis in 7 patients and 1 patient had a patent, highly attenuated artery. Detection of a patent hepatic artery increased from 759 of 794 (95.6%) to 781 of 794 (98.4%) with the addition of microbubble contrast. Upon independent reading of the data, the degree of operator confidence in the assessment of the hepatic artery patency prior to microbubble contrast was 4.7 (CI 1.92-7.5) but rose to 8.45 (CI 7.06-9.84) following microbubble contrast ( p<0.0001). In 22 of 35 (62.9%) of studies arteriography could potentially have been avoided. Ultrasound microbubble contrast media may reduce the need for invasive arteriography in the assessment of suspected hepatic artery thrombosis.


Assuntos
Arteriopatias Oclusivas/diagnóstico por imagem , Artéria Hepática , Transplante de Fígado/efeitos adversos , Microbolhas , Ultrassonografia Doppler em Cores , Adulto , Angiografia/estatística & dados numéricos , Arteriopatias Oclusivas/fisiopatologia , Estudos de Coortes , Intervalos de Confiança , Feminino , Humanos , Aumento da Imagem , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Probabilidade , Estudos Prospectivos , Medição de Risco , Estatísticas não Paramétricas , Grau de Desobstrução Vascular
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