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1.
Clin Imaging ; 105: 110020, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37989020

RESUMO

Infant femoral arterial access is an essential part of interventional procedures, hemodynamic monitoring, and support of critically ill patients. Due to small luminal diameter, superficial location, mobility, and increased risk of vasospasm, dissection, and thrombosis, femoral artery access in the infant is a technically demanding procedure. The purpose of this manuscript is to describe an approach to successful common femoral arterial access and arteriography in infants including common pearls and pitfalls.


Assuntos
Trombose , Doenças Vasculares , Lactente , Humanos , Angiografia , Artéria Femoral/diagnóstico por imagem
2.
Clin Oncol (R Coll Radiol) ; 35(2): e135-e142, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36336579

RESUMO

AIMS: Neoadjuvant chemoradiotherapy followed by surgery is the mainstay of treatment for patients with rectal cancer. Standard clinical target volume (CTV) to planning target volume (PTV) margins of 10 mm are used to accommodate inter- and intrafraction motion of target. Treating on magnetic resonance-integrated linear accelerators (MR-linacs) allows for online manual recontouring and adaptation (MRgART) enabling the reduction of PTV margins. The aim of this study was to investigate motion of the primary CTV (CTVA; gross tumour volume and macroscopic nodes with 10 mm expansion to cover microscopic disease) in order to develop a simultaneous integrated boost protocol for use on MR-linacs. MATERIALS AND METHODS: Patients suitable for neoadjuvant chemoradiotherapy were recruited for treatment on MR-linac using a two-phase technique; only the five phase 1 fractions on MR-linac were used for analysis. Intrafraction motion of CTVA was measured between pre-treatment and post-treatment MRI scans. In MRgART, isotropically expanded pre-treatment PTV margins from 1 to 10 mm were rigidly propagated to post-treatment MRI to determine overlap with 95% of CTVA. The PTV margin was considered acceptable if overlap was >95% in 90% of fractions. To understand the benefit of MRgART, the same methodology was repeated using a reference computed tomography planning scan for pre-treatment imaging. RESULTS: In total, nine patients were recruited between January 2018 and December 2020 with T3a-T4, N0-N2, M0 disease. Forty-five fractions were analysed in total. The median motion across all planes was 0 mm, demonstrating minimal intrafraction motion. A PTV margin of 3 and 5mm was found to be acceptable in 96 and 98% of fractions, respectively. When comparing to the computed tomography reference scan, the analysis found that PTV margins to 5 and 10 mm only acceptably covered 51 and 76% of fractions, respectively. CONCLUSION: PTV margins can be reduced to 3-5 mm in MRgART for rectal cancer treatment on MR-linac within an simultaneous integrated boost protocol.


Assuntos
Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Neoplasias Retais , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Tomografia Computadorizada por Raios X , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/radioterapia , Neoplasias Retais/patologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos
3.
Clin Transl Radiat Oncol ; 35: 27-32, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35571274

RESUMO

Bladder tumour-focused magnetic resonance image-guided adaptive radiotherapy using a 1.5 Tesla MR-linac is feasible. A full online workflow adapting to anatomy at each fraction is achievable in approximately 30 min. Intra-fraction bladder filling did not compromise target coverage with the class solution employed.

4.
Alcohol Alcohol ; 56(6): 651-659, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33418568

RESUMO

AIM: Investigate changes in alcohol use and related harm using the first multisite, controlled, longitudinal study of Managed Alcohol Programs (MAPs). MAPs provide regular doses of alcohol, accommodation, social supports and healthcare to unstably housed people with alcohol dependence. METHODS: A multisite, quasi-experimental, longitudinal study was conducted in day centres, shelters and residential programs for unstably housed people. There were 59 MAP participants from six Canadian cities and 116 local controls. Self-reported alcohol consumption and harms were assessed at 0-2, 6 and 12 months. Liver function test results were accessed for MAP participants. RESULTS: Both groups had similar reductions in mean drinks per day (MAP: -8.11; controls: -8.54 controls, P < 0.001) and days drinking per month (MAP: -2.51 days, P < 0.05; control: -4.81 days, P = 0.0001) over 6--12 months. Both reduced non-beverage alcohol consumption. MAP participants reported significantly fewer harms at both 0-2 and 6 months than controls. MAP participants had similar total consumption to controls, but spread out over more days (25.41 versus 19.64 days per month, P = 0.001). After leaving a MAP, participants' liver status deteriorated, with increases in both aspartate transaminase and bilirubin levels. MAP sites with effective policies on outside drinking drank less and had fewer harms. CONCLUSION: MAP participants drank less hazardously than controls, especially with effective management of non-MAP drinking. Reductions in alcohol use and harms occurred for both groups, although MAP participants reported fewer harms at 0-6 months. Departing an MAP was associated with deterioration in liver status. Although providing stable housing, MAPs did not worsen health or increase alcohol use.


Assuntos
Consumo de Bebidas Alcoólicas/prevenção & controle , Alcoolismo/reabilitação , Redução do Dano , Avaliação de Programas e Projetos de Saúde , Adulto , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/tendências , Alcoolismo/epidemiologia , Canadá/epidemiologia , Estudos de Casos e Controles , Cidades/epidemiologia , Etanol/administração & dosagem , Feminino , Habitação , Humanos , Testes de Função Hepática , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Apoio Social
5.
Clin Transl Radiat Oncol ; 25: 46-51, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33015380

RESUMO

Whole bladder magnetic resonance image-guided radiotherapy using the 1.5 Telsa MR-linac is feasible. Full online adaptive planning workflow based on the anatomy seen at each fraction was performed. This was delivered within 45 min. Intra-fraction bladder filling did not compromise target coverage. Patients reported acceptable tolerance of treatment.

6.
Lymphology ; 52(2): 52-60, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31525826

RESUMO

The purpose of this study was to demonstrate the feasibility of percutaneous fluoroscopically-guided transcervical retrograde access into the thoracic duct following unsuccessful transabdominal cisterna chyli cannulation to perform thoracic duct embolization for the treatment of chylothorax. Five patients, including three (60%) women and two (40%) men, with median age of 62 years, underwent percutaneous transcervical thoracic duct access and embolization after failed transabdominal cisterna chyli cannulation for the treatment of chylothorax. In all patients, fluoroscopically-guided percutaneous transcervical retrograde access into the distal thoracic duct was achieved using a 21-gauge needle and an 0.018-inch wire. Following advancement of a microcatheter, retrograde lymphangiography was performed to identify the location of thoracic duct injury. A combination of 2:1 ethiodized oil to cyanoacrylate mixtures, platinum microcoils, or stent-grafts were used to treat the chylous leaks. Technical successes, procedure durations, fluoroscopy times, blood losses, immediate adverse events, clinical successes, and follow-up durations were recorded. Technical success was defined as cannulation of the distal thoracic duct using a transcervical approach followed by treatment of the thoracic duct injury. Adverse events were classified according to the Society of Interventional Radiology guidelines. Clinical success was defined as resolution of the presenting chylothorax. Percutaneous transcervical retrograde thoracic duct access and treatment was technically successful in all patients (n=5). Median procedure duration was 173 minutes (range: 136-347 minutes) with a median fluoroscopy time of 94.7 minutes (range: 47-125 minutes). Median blood loss was 10 mL (range: 5-20 mL). No minor or major adverse occurred. Clinical success was achieved in all patients (n=5). Median follow-up was 372 days (range: 67-661 days). Percutaneous fluoroscopically- guided transcervical retrograde thoracic duct access is an effective and safe method to perform thoracic duct embolization following unsuccessful transabdominal cisterna chyli cannulation for the treatment of chylothorax.


Assuntos
Quilotórax/terapia , Embolização Terapêutica , Fluoroscopia , Linfografia , Cirurgia Assistida por Computador , Ducto Torácico , Adulto , Idoso , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Feminino , Fluoroscopia/métodos , Humanos , Linfografia/métodos , Masculino , Pessoa de Meia-Idade , Retratamento , Cirurgia Assistida por Computador/efeitos adversos , Cirurgia Assistida por Computador/métodos , Falha de Tratamento , Resultado do Tratamento
8.
Diagn Interv Imaging ; 99(1): 9-14, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28624300

RESUMO

PURPOSE: To evaluate current and recent interventional radiology (IR) fellows' perceptions on the new integrated IR residency. MATERIALS AND METHODS: An anonymous, web-based survey was distributed to 82 current and recent IR fellows across the Unites States. The survey contained 15 questions, most of which were based on a five-point Likert scale. The survey was open for a three-week period in September 2015. The results were analyzed by two trainees and three IR attending physicians. RESULTS: Sixty-four current or recent former IR fellows completed the survey (response rate 78%). Of these 18% decided to pursue a career in IR by the end of their third year of medical school. A majority believed that the integrated IR residency will be an improved IR training pathway (62%). Based on current medical school curricula, 74% either disagreed or strongly disagreed that IR residency applicants will be ready to select such a pathway by the end of their third year of medical school. CONCLUSIONS: Most current and recent IR fellows surveyed chose IR during their final year of medical school or during residency. Most respondents believe that the integrated IR residency will be an improved IR training pathway.


Assuntos
Escolha da Profissão , Bolsas de Estudo , Radiologia Intervencionista/educação , Humanos , Internato e Residência , Inquéritos e Questionários , Estados Unidos
9.
Alcohol Alcohol ; 52(6): 722-729, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29016713

RESUMO

AIMS: To explore the potential impact of a minimum unit price (MUP: 50 pence per UK unit) on the alcohol consumption of ill Scottish heavy drinkers. METHODS: Participants were 639 patients attending alcohol treatment services or admitted to hospital with an alcohol-related condition. From their reported expenditure on alcohol in their index week, and assuming this remained unchanged, we estimated the impact of a MUP (50 ppu) on future consumption. (Around 15% purchased from both the more expensive on-sale outlets (hotels, pubs, bars) and from off-sales (shops and supermarkets). For them we estimated the change in consumption that might follow MUP if (i) they continued this proportion of 'on-sales' purchasing or (ii) their reported expenditure was moved entirely to off-sale purchasing (to maintain consumption levels)). RESULTS: Around 69% of drinkers purchased exclusively off-sale alcohol at <50 ppu. Their drinking, post MUP, may reduce by a mean of 33%. For this group, from a population of very heavy, ill consumers, we were unable to show a differential effect across multiple deprivation quintiles. For other drinkers there might be no reduction, especially if after MUP there were many products priced close to 50 ppu. Moving away from on-sales purchases could support, for some, an increase in consumption. CONCLUSIONS: While a proportion of our harmed, heavy drinkers might be able to mitigate the impact of MUP by changing purchasing habits, the majority are predicted to reduce purchasing. This analysis, focusing specifically on harmed drinkers, adds a unique dimension to the evidence base informing current pricing policy. SHORT SUMMARY: From drink purchasing data of heavy drinkers, we estimated the impact of legislating £0.50 minimum unit price. Over two thirds of drinkers, representing all multiple deprivation quintiles, were predicted to decrease alcohol purchasing; remainder, hypothetically, could maintain consumption. Our data address an important gap within the evidence base informing policy.


Assuntos
Consumo de Bebidas Alcoólicas/economia , Consumo de Bebidas Alcoólicas/prevenção & controle , Bebidas Alcoólicas/economia , Intoxicação Alcoólica/economia , Intoxicação Alcoólica/prevenção & controle , Custos e Análise de Custo/economia , Consumo de Bebidas Alcoólicas/epidemiologia , Transtornos Relacionados ao Uso de Álcool/economia , Transtornos Relacionados ao Uso de Álcool/epidemiologia , Transtornos Relacionados ao Uso de Álcool/prevenção & controle , Intoxicação Alcoólica/epidemiologia , Feminino , Humanos , Masculino , Escócia/epidemiologia , Inquéritos e Questionários
10.
Diagn Interv Imaging ; 98(11): 801-808, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28416166

RESUMO

PURPOSE: To assess the 2-year effectiveness and safety of balloon-occluded retrograde transvenous obliteration (BRTO) for gastric varices (GVs) in liver transplant recipients. MATERIALS AND METHODS: Eleven liver transplant recipients underwent consecutive BRTO for GVs at four institutions. Patients included eight (73%) men and three (27%) women with mean age of 56 years±12 (SD) (range: 26-67 years). Underlying cause of liver transplantation was hepatitis C virus (HCV)-related cirrhosis in five (45%), alcohol- and HCV-related cirrhosis in three (27%), primary biliary cirrhosis in two (18%), and alcoholic cirrhosis in one (9%). Five (45%) patients underwent BRTO for actively bleeding GVs, three (17%) for high-risk GVs, and three (17%) for augmentation of portal venous flow through obliteration of gastrorenal shunts. Mean time between liver transplantation and BRTO was 78 months (range: 0.1-276 months). Technical success, GVs obliterative rates, and immediate complications were recorded. Post-BRTO hemorrhagic, transplant, and overall survival rates were evaluated at 6, 12, and 24 months. RESULTS: All (100%) procedures were technically successful. Complete GVs obliteration was achieved in ten patients (91%). Two major complications (18%) occurred in the immediate post-procedure period. One patient developed complete portal vein thrombosis, and another patient developed consumptive coagulopathy, ultimately leading to death. No post-BRTO hemorrhagic recurrences were seen at 6, 12, or 24 months. One patient (9%) had delayed upper gastrointestinal bleeding at 34 months after the procedure which was managed conservatively. Transplant and overall survival rates were 91% at 6, 12, and 24 months. CONCLUSION: BRTO has high technical success and complete GVs obliterative rates in liver transplant recipients with few complications and high graft survival rates.


Assuntos
Oclusão com Balão , Varizes Esofágicas e Gástricas/terapia , Hemorragia Gastrointestinal/terapia , Transplante de Fígado , Adulto , Idoso , Oclusão com Balão/efeitos adversos , Varizes Esofágicas e Gástricas/complicações , Feminino , Hemorragia Gastrointestinal/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Transplantados
12.
Public Health ; 129(12): 1571-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26411488

RESUMO

OBJECTIVES: Potential strategies to address alcohol misuse remain contentious. We aim to characterise the drink purchases of one population group: heavy drinkers in contact with Scottish health services. We contrast our findings with national sales data and explore the impact of socio-economic status on purchasing behaviour. STUDY DESIGN: Cross-sectional study comparing alcohol purchasing and consumption by heavy drinkers in Edinburgh and Glasgow during 2012. METHODS: 639 patients with serious health problems linked to alcohol (recruited within NHS hospital clinics (in- and out-patient settings) 345 in Glasgow, 294 in Edinburgh) responded to a questionnaire documenting demographic data and last week's or a 'typical' weekly consumption (type, brand, volume, price, place of purchase). Scottish Index of Multiple Deprivation quintile was derived as proxy of sociodemographic status. RESULTS: Median consumption was 184.8 (IQR = 162.2) UK units/week paying a mean of 39.7 pence per alcohol unit (£0.397). Off-sales accounted for 95% of purchases with 85% of those <50 pence (£0.5 UK) per alcohol unit. Corresponding figures for the Scottish population are 69% and 60%. The most popular low-priced drinks were white cider, beer and vodka with the most common off-sales outlet being the corner shop, despite supermarkets offering cheaper options. Consumption levels of the cheapest drink (white cider) were similar across all quintiles apart from the least deprived. CONCLUSIONS: Heavy drinkers from all quintiles purchase the majority of their drinks from off-sale settings seeking the cheapest drinks, often favouring local suppliers. While beer was popular, recent legislation impacting on the sale of multibuys may prevent the heaviest drinkers benefiting from the lower beer prices available in supermarkets. Non-etheless, drinkers were able to offset higher unit prices with cheaper drink types and maintain high levels of consumption. Whilst price is key, heavy drinkers are influenced by other factors and adapt their purchasing as necessary.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Bebidas Alcoólicas/economia , Comércio/estatística & dados numéricos , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Escócia , Classe Social , Inquéritos e Questionários
13.
Public Health ; 127(8): 735-44, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23886343

RESUMO

OBJECTIVE: To determine how healthcare professionals, family members and community members responded to an art exhibit created by people living with mental illness. STUDY DESIGN: Phenomenological study with qualitative analysis. METHODS: Forty-six participants with various relationships with people living with mental illness attended an art therapy exhibit and art making workshop. Surveys, response art, reflective writing and discussion groups were used in this qualitative research study. RESULTS: Responses were categorized into four cluster themes: empathic, self-oriented, other-oriented and world-oriented. CONCLUSIONS: Each response category has strengths and weaknesses, indicating implications for increasing awareness and understanding of the artists and mental illness. They also inform educational interventions that can be utilized when using art exhibits for the purpose of confronting bias and stigma towards people living with mental illness.


Assuntos
Arteterapia , Empatia , Exposições como Assunto , Família/psicologia , Pessoal de Saúde/psicologia , Transtornos Mentais/psicologia , Opinião Pública , Adulto , Idoso , Feminino , Hong Kong , Humanos , Masculino , Transtornos Mentais/terapia , Pessoa de Meia-Idade , Pesquisa Qualitativa , Mudança Social , Estigma Social , Adulto Jovem
14.
Alcohol Alcohol ; 47(6): 702-10, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22986010

RESUMO

AIMS: To identify prognostic factors to outpatient alcohol treatment on admission as well as during the treatment period. METHODS: A cohort study of n = 209 alcoholic patients (DSM-IV) during 6 months of outpatient treatment. Eight medical doctors from two hospitals were involved. Co-responsible participation in treatment was a necessary condition. At admission, we documented socio demographic factors, use of other drugs and severity of alcohol consumption. During the 6 months, we observed medication for prevention of alcohol relapse [disulfiram (DIS), acamprosate], number of sessions with the doctor, number of phases of the consultation and medication for depression. Primary outcome variables were time to first heavy relapse and abstinence of heavy alcohol consumption. These were measured with Timeline Followback. Five or more alcohol units of 10 g in one relapse day were considered heavy relapse. RESULTS: The patients were 84% males, with 41 years median age; the median alcohol consumption was 192 g per day with a median duration of 13 years of heavy consumption. The median education was 6 years with 61% of the patients from lower socio-economic levels. The Kaplan-Meier heavy relapse rate at 6 months was 23%. On admission to treatment, female gender, lower socio-economic levels, cocaine use, >20 years of consumption, gamma glutamyl transferase values above normal and five or more alcohol-related problems on the Alcohol-Related Problem Questionnaire predicted worse outcomes. Having a full-time job and shorter abstinence time before treatment (until 7 days) predicted better outcomes. During the 6 months, we found that DIS for <120 days was a prognostic factor of worse outcomes. DIS for at least 120 days, >50% of adherence to consultations and more than two phases on each consultation predicted better outcomes. The combined sensitivity and specificity for DIS for at least 120 days, >50% of adherence to consultations and more than two phases on consultation regarding abstinence from heavy relapse were respectively 100 and 71%. CONCLUSIONS: During 6 months of outpatient treatment, longer adherence to DIS and consultations as well as more phases in a consultation involving necessarily a co-responsible predict a good outcome independently of the patient features at admission.


Assuntos
Alcoolismo/diagnóstico , Alcoolismo/terapia , Assistência Ambulatorial/tendências , Temperança/tendências , Adulto , Alcoolismo/epidemiologia , Assistência Ambulatorial/métodos , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
16.
Environ Monit Assess ; 157(1-4): 211-22, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18850294

RESUMO

Populations of invasive fishes quickly reach extremely high biomass. Before control methods can be applied, however, an understanding of the contaminant loads of these invaders carry is needed. We investigated differences in concentrations of selected elements in two invasive carp species as a function of sampling site, fish species, length and trophic differences using stable isotopes (delta (15)N, delta (13)C). Fish were collected from three different sites, the Illinois River near Havana, Illinois, and two sites in the Mississippi River, upstream and downstream of the Illinois River confluence. Five bighead carp (Hypophthalmichthys nobilis) and five silver carp (Hypophthalmichthys molitrix) from each site were collected for muscle tissue analyses. Freshwater mussels (Amblema plicata) previously collected in the same areas were used as an isotopic baseline to standardize fish results among sites. Total fish length, trophic position, and corrected (13)C, were significantly related to concentrations of metals in muscle. Fish length explained the most variation in metal concentrations, with most of that variation related to mercury levels. This result was not unexpected because larger fish are older, giving them a higher probability of exposure and accumulation of contaminants. There was a significant difference in stable isotope profiles between the two species. Bighead carp occupied a higher trophic position and had higher levels of corrected (13)C than silver carp. Additionally bighead carp had significantly lower concentrations of arsenic and selenium than silver carp. Stable isotope ratios of nitrogen in Asian carp were at levels that are more commonly associated with higher-level predators, or from organisms in areas containing high loads of wastewater effluent.


Assuntos
Arsênio/metabolismo , Carpas/metabolismo , Rios/química , Selênio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Dieta , Monitoramento Ambiental , Cadeia Alimentar , Geografia , Illinois , Unionidae/metabolismo
17.
J Proteome Res ; 7(11): 4974-81, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18837535

RESUMO

Membrane protein analyses have been notoriously difficult due to hydrophobicity and the general low abundance of these proteins compared to their soluble cytosolic counterparts. Shotgun proteomics has become the preferred method for analyses of membrane proteins, in particular the recent development of peptide immobilized pH gradient isoelectric focusing (IPG-IEF) as the first dimension of two-dimensional shotgun proteomics. Recently, peptide IPG-IEF has been shown to be a valuable shotgun proteomics technique through the use of acidic narrow range IPG strips, which demonstrated that small acidic p I increments are rich in peptides. In this study, we assess the utility of both broad range (BR) (p I 3-10) and narrow range (NR) (p I 3.4-4.9) IPG strips for rat liver membrane protein analyses. Furthermore, the use of these IPG strips was evaluated using label-free quantitation to demonstrate that the identification of a subset of proteins can be improved using NR IPG strips. NR IPG strips provided 2603 protein assignments on average (with 826 integral membrane proteins (IMPs)) compared to BR IPG strips, which provided 2021 protein assignments on average (with 712 IMPs). Nonredundant protein analysis demonstrated that in total from all experiments, 4195 proteins (with 1301 IMPs) could be identified with 1428 of these proteins unique to NR IPG strips with only 636 from BR IPG strips. With the use of label-free quantitation methods, 1659 proteins were used for quantitative comparison of which 319 demonstrated statistically significant increases in normalized spectral abundance factors (NSAF) in NR IPG strips compared to 364 in BR IPG strips. In particular, a selection of six highly hydrophobic transmembrane proteins was observed to increase in NSAF using NR IPG strips. These results provide evidence for the use of alternative pH gradients in combination to improve the shotgun proteomic analysis of the membrane proteome.


Assuntos
Membrana Celular/química , Proteínas de Membrana/química , Peptídeos/química , Proteoma , Animais , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Fígado/citologia , Modelos Biológicos , Proteômica/métodos , Ratos , Ratos Endogâmicos
18.
J Proteome Res ; 7(3): 1036-45, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18211008

RESUMO

Membrane proteins are of particular interest in proteomics because of their potential therapeutic utility. Past proteomic approaches used to investigate membrane proteins have only been partially successful at providing a comprehensive analysis due to the inherently hydrophobic nature and low abundance for some of these proteins. Recently, these difficulties have been improved by analyzing membrane protein enriched samples using shotgun proteomics. In addition, the recent application of methanol-assisted trypsin digestion of membrane proteins has been shown to be a method to improve membrane protein identifications. In this study, a comparison of different concentrations of methanol was assessed for assisting membrane protein digestion with trypsin prior to analysis using a gel-based shotgun proteomics approach called peptide immobilized pH gradient isoelectric focusing (IPG-IEF). We demonstrate the use of peptide IEF on pH 3-10 IPG strips as the first dimension of two-dimensional shotgun proteomics for protein identifications from the membrane fraction of rat liver. Tryptic digestion of proteins was carried out in varying concentrations of methanol in 10 mM ammonium bicarbonate: 0% (v/v), 40% (v/v), and 60% (v/v). A total of 800 proteins were identified from 60% (v/v) methanol, which increased the protein identifications by 17% and 14% compared to 0% (v/v) methanol and 40% (v/v) methanol assisted digestion, respectively. In total, 1549 nonredundant proteins were identified from all three concentrations of methanol including 690 (42%) integral membrane proteins of which 626 of these proteins contained at least one transmembrane domain. Peptide IPG-IEF separation of peptides was successful as the peptides were separated into discrete pI regions with high resolution. The results from this study prove utility of 60% (v/v) methanol assisted digestion in conjunction with peptide IPG-IEF as an optimal shotgun proteomics technique for the separation and identification of previously unreported membrane proteins.


Assuntos
Focalização Isoelétrica/métodos , Fígado/química , Proteínas de Membrana/química , Peptídeos/química , Proteoma , Animais , Concentração de Íons de Hidrogênio , Ratos
19.
Cancer Chemother Pharmacol ; 61(4): 579-85, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17520255

RESUMO

PURPOSE: OSI-7904L is a liposomal formulation of a potent thymidylate synthase (TS) inhibitor. This phase I study evaluated the safety, tolerability and pharmacokinetics (PK) of OSI-7904L administered in combination with oxaliplatin every 21 days in patients with advanced colorectal carcinoma. METHOD: A 3+3 study design was utilized at predefined dose levels. Polymorphisms in the TS enhancer region and XPD enzyme were investigated as potential predictors of efficacy and toxicity. RESULTS: Fourteen patients received 76 cycles of treatment. At the highest dose level (OSI-7904L 9 mg/m(2), oxaliplatin 130 mg/m(2)) investigated, one of nine patients experienced dose-limiting toxicity of grade 3 oral mucositis with cycle 1 and five further patients required dose reductions. The toxicity profile of stomatitis, diarrhea, nausea, fatigue, sensory neuropathy and skin rash was consistent with that expected for a TS inhibitor/oxaliplatin combination regimen. PK analysis showed high interpatient variability with no detectable interaction between OSI-7904L and oxaliplatin. Partial radiological responses were documented in two patients. CONCLUSIONS: The recommended regimen for further investigation is OSI-7904L 9 mg/m(2) and oxaliplatin 130 mg/m(2).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Timidilato Sintase/antagonistas & inibidores , Idoso , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Feminino , Glutaratos/administração & dosagem , Humanos , Isoindóis/administração & dosagem , Lipossomos , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Farmacogenética , Polimorfismo Genético , Quinazolinas/administração & dosagem , Timidilato Sintase/genética
20.
Invest New Drugs ; 25(4): 385-90, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17364234

RESUMO

The prognosis of advanced biliary tract carcinoma is poor with chemotherapy limited to a palliative role. This randomised study was designed to evaluate the effectiveness of a new liposomal thymidylate synthase inhibitor (TSI), OSI-7904L, in parallel with a modified de Gramont regimen of 5-FU/LV in patients with advanced biliary cancer. Patients with previously untreated advanced or metastatic carcinoma of the biliary tract were randomised to receive either OSI-7904L 12 mg/m2 intravenously every 21 days or a modified de Gramont schedule of 5-FU/LV (intravenous l-LV 200 mg/m2, bolus 5-FU 400 mg/m2 and a 46-h infusion of 5-FU 2,400 mg/m2) every 14 days. Twenty-two patients were randomised, 11 to each group. No patients responded in the OSI-7904L arm, while one patient achieved a partial response in the 5-FU/LV arm. The rates of disease stabilisation were 4/11 (OSI-7904L) and 10/11 (5-FU/LV). Both treatment arms were generally well tolerated. These results show that the activity of OSI-7904L is below a level of clinical relevance in advanced biliary tract cancer, providing only a small degree of disease stabilisation. A simplified de Gramont schedule appears to have marginally more activity. Both treatments were well tolerated.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Biliar/tratamento farmacológico , Glutaratos/uso terapêutico , Quinazolinas/uso terapêutico , Adenocarcinoma/secundário , Neoplasias do Sistema Biliar/patologia , Feminino , Fluoruracila/administração & dosagem , Humanos , Isoindóis , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Timidilato Sintase/antagonistas & inibidores , Resultado do Tratamento
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