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1.
BMJ Open ; 12(10): e063594, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36270757

RESUMO

PURPOSE: Risk factor-based models struggle to accurately predict the development of cardiovascular disease (CVD) at the level of the individual. Ways of identifying people with low predicted risk who will develop CVD would allow stratified advice and support informed treatment decisions about the initiation or adjustment of preventive medication, and this is the aim of this prospective cohort study. PARTICIPANTS: The Tayside Screening for Cardiac Events (TASCFORCE) study recruited men and women aged≥40 years, free from known CVD, with a predicted 10-year risk of coronary heart disease<20%. If B-type natriuretic peptide (BNP) was greater than their gender median, participants were offered a whole-body contrast-enhanced MRI (WBCE-MRI) scan (cardiac imaging, whole-body angiography to determine left ventricular parameters, delayed gadolinium enhancement, atheroma burden). Blood, including DNA, was stored for future biomarker assays. Participants are being followed up using electronic record-linkage cardiovascular outcomes. FINDINGS TO DATE: 4423 (1740, 39.3% men) were recruited. Mean age was 52.3 years with a median BNP of 7.50 ng/L and 15.30 ng/L for men and women, respectively. 602 had a predicted 10-year risk of 10%-19.9%, with the remainder<10%. Age, female sex, ex-smoking status, lower heart rate, higher high-density lipoprotein and lower total cholesterol were independently associated with higher log10 BNP levels. Mean left ventricular mass was 129.2 g and 87.0 g in men and women, respectively. FUTURE PLANS: The TASCFORCE study is investigating the ability of a screening programme, using BNP and WBCE-MRI, at the time of enrolment, to evaluate prediction of CVD in a population at low/intermediate risk. Blood stored for future biomarker analyses will allow testing/development of novel biomarkers. We believe this could be a new UK Framingham study allowing study for many years to come. CLINICAL TRIAL REGISTRATION: ISRCTN38976321.


Assuntos
Doenças Cardiovasculares , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Peptídeo Natriurético Encefálico , Gadolínio , Meios de Contraste , Fatores de Risco , Fatores de Risco de Doenças Cardíacas , Biomarcadores , Colesterol , Lipoproteínas HDL
2.
Lancet Oncol ; 23(4): 501-513, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35279270

RESUMO

BACKGROUND: Early diagnosis of malignant spinal cord compression (SCC) is crucial because pretreatment neurological status is the major determinant of outcome. In metastatic castration-resistant prostate cancer, SCC is a clinically significant cause of disease-related morbidity and mortality. We investigated whether screening for SCC with spinal MRI, and pre-emptive treatment if radiological SCC (rSCC) was detected, reduced the incidence of clinical SCC (cSCC) in asymptomatic patients with metastatic castration-resistant prostate cancer and spinal metastasis. METHODS: We did a parallel-group, open-label, randomised, controlled, phase 3, superiority trial. Patients with metastatic castration-resistant prostate cancer were recruited from 45 National Health Service hospitals in the UK. Eligible patients were aged at least 18 years, with an Eastern Co-operative Oncology Group performance status of 0-2, asymptomatic spinal metastasis, no previous SCC, and no spinal MRI in the past 12 months. Participants were randomly assigned (1:1), using a minimisation algorithm with a random element (balancing factors were treatment centre, alkaline phosphatase [normal vs raised, with the upper limit of normal being defined at each participating laboratory], number of previous systemic treatments [first-line vs second-line or later], previous spinal treatment, and imaging of thorax and abdomen), to no MRI (control group) or screening spinal MRI (intervention group). Serious adverse events were monitored in the 24 h after screening MRI in the intervention group. Participants with screen-detected rSCC were offered pre-emptive treatment (radiotherapy or surgical decompression was recommended per treating physician's recommendation) and 6-monthly spinal MRI. All patients were followed up every 3 months, and then at month 30 and 36. The primary endpoint was time to and incidence of confirmed cSCC in the intention-to-treat population (defined as all patients randomly assigned), with the primary timepoint of interest being 1 year after randomisation. The study is registered with ISRCTN, ISRCTN74112318, and is now complete. FINDINGS: Between Feb 26, 2013, and April 25, 2017, 420 patients were randomly assigned to the control (n=210) or screening MRI (n=210) groups. Median age was 74 years (IQR 68 to 79), 222 (53%) of 420 patients had normal alkaline phosphatase, and median prostate-specific antigen concentration was 48 ng/mL (IQR 17 to 162). Screening MRI detected rSCC in 61 (31%) of 200 patients with assessable scans in the intervention group. As of data cutoff (April 23, 2020), at a median follow-up of 22 months (IQR 13 to 31), time to cSCC was not significantly improved with screening (hazard ratio 0·64 [95% CI 0·37 to 1·11]; Gray's test p=0·12). 1-year cSCC rates were 6·7% (95% CI 3·8-10·6; 14 of 210 patients) for the control group and 4·3% (2·1-7·7; nine of 210 patients) for the intervention group (difference -2·4% [95% CI -4·2 to 0·1]). Median time to cSCC was not reached in either group. No serious adverse events were reported within 24 h of screening. INTERPRETATION: Despite the substantial incidence of rSCC detected in the intervention group, the rate of cSCC in both groups was low at a median of 22 months of follow-up. Routine use of screening MRI and pre-emptive treatment to prevent cSCC is not warranted in patients with asymptomatic castration-resistant prostate cancer with spinal metastasis. FUNDING: Cancer Research UK.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Compressão da Medula Espinal , Neoplasias da Coluna Vertebral , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Detecção Precoce de Câncer , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/etiologia , Neoplasias da Coluna Vertebral/complicações , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Medicina Estatal , Reino Unido/epidemiologia
3.
Front Plant Sci ; 12: 626483, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33719298

RESUMO

We showed previously that gallic acid is produced in walnut from 3-dehydroshikimate by a shikimate dehydrogenase (JrSkDH). This study focuses on the next step in the hydrolysable tannin pathway, the formation of 1-O-galloyl-ß-D-glucose from the phenolic gallic acid and UDP glucose by a glycosyltransferase. JrGGT1 (UGT84A73) and JrGGT2 (UGT84A74) are predicted to be two such glycosyltransferases, which we expressed in tobacco plants. GC-MS analysis of the transgenic tobacco revealed moderate, yet significant alterations in plant secondary metabolism, such as depleted phenolic acids, including gallic acid. We postulate that these effects are due to JrGGT1 and JrGGT2 activity, as JrGGT orthologs glycosylate these phenolic compounds in vitro. Moreover, JrGGT expression in tobacco caused upregulation of shikimic acid pathway metabolites and differing responses in phenylpropanoids, such as phenolic acids and flavonoids. In transcriptome analysis of walnut pellicle tissues, both JrGGTs showed substantial and significant expression correlations with the gallic acid-producing JrSkDHs and were highly coexpressed with the genetic circuits constituting the shikimic acid and phenylpropanoid biosynthetic pathways. Verification of JrGGT gene expression by transcriptome analysis of 20 walnut tissues revealed striking similarities with that of the pellicle data, with the greatest expression in roots, wood, buds, and leaves of Juglans regia cv. Chandler: tissues that typically accumulate hydrolysable tannins. Like the transgenic tobacco, pellicle metabolomic analyses revealed that many phenylpropanoids correlated negatively with JrGGT expression, while shikimic acid pathway metabolites correlated positively with JrGGT expression. This research supports the hypothesis that JrGGT1 and JrGGT2 play non-trivial roles in metabolism of phenolic acids, flavonoids, and ostensibly, tannins.

4.
Life (Basel) ; 10(12)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33261033

RESUMO

Walnuts (Juglans regia L.) are a valuable dietary source of polyphenols and lipids, with increasing worldwide consumption. California is a major producer, with 'Chandler' and 'Tulare' among the cultivars more widely grown. 'Chandler' produces kernels with extra light color at a higher frequency than other cultivars, gaining preference by growers and consumers. Here we performed a deep comparative proteome analysis of kernel pellicle tissue from these two valued genotypes at three harvest maturities, detecting a total of 4937 J. regia proteins. Late and early maturity stages were compared for each cultivar, revealing many developmental responses common or specific for each cultivar. Top protein biomarkers for each developmental stage were also selected based on larger fold-change differences and lower variance among replicates, including proteins for biosynthesis of lipids and phenols, defense-related proteins and desiccation stress-related proteins. Comparison between the genotypes also revealed the common and specific protein repertoires, totaling 321 pellicle proteins with differential abundance at harvest stage. The proteomics data provides clues on antioxidant, secondary, and hormonal metabolism that could be involved in the loss of quality in the pellicles during processing for commercialization.

5.
Int J Chron Obstruct Pulmon Dis ; 15: 2015-2024, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32904701

RESUMO

Background: Oxidative stress (OS) has been implicated in the development of pulmonary hypertension (PH) and ventricular hypertrophy. Xanthine oxidase is a well-recognised source of reactive oxygen species, which lead to OS. The aim of this proof of concept study was to assess whether allopurinol (xanthine oxidase inhibitor) would reduce right ventricular mass (RVM) in patients with PH-associated chronic lung disease (PH-CLD). Methods: We conducted a randomised, double-blind, parallel-group, placebo-controlled trial in patients with PH-CLD (93% COPD, 7% IPF) who were randomly assigned to receive allopurinol or placebo for 12 months. The primary outcome was the mean change in RVM, as assessed by cardiac magnetic resonance imaging (CMRI). Secondary outcomes included quality of life (QOL), spirometry and six-minute walk test (6MWT). Results: Seventy-one patients were recruited: mean age 71 years, mean pulmonary arterial pressure 30 mm Hg, FEV1 60% and resting SpO2 96%. After 12 months, there was no significant difference in the change in RVM from baseline (allopurinol 1.85g vs placebo 0.97g with mean difference 0.88g, CI -4.77 to 3.01, p =0.7). There were also no significant changes in other cardiac parameters measured on MRI, in QOL, spirometry and 6MWT. Subgroup analysis showed that allopurinol significantly reduced RVM compared to placebo with -6.16g vs 0.75g and mean difference 6.92g (CI 1.14 to 12.69, p = 0.02) in COPD patients with more severe airflow limitation. Conclusion: Allopurinol had no overall impact on patients with PH-CLD but had potential benefit in COPD patients with more severe airflow limitation.


Assuntos
Hipertensão Pulmonar , Doença Pulmonar Obstrutiva Crônica , Idoso , Alopurinol/efeitos adversos , Método Duplo-Cego , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Qualidade de Vida , Teste de Caminhada
6.
ChemMedChem ; 15(20): 1862-1874, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-32743945

RESUMO

Passive permeability is a key property in drug disposition and delivery. It is critical for gastrointestinal absorption, brain penetration, renal reabsorption, defining clearance mechanisms and drug-drug interactions. Passive diffusion rate is translatable across tissues and animal species, while the extent of absorption is dependent on drug properties, as well as in vivo physiology/pathophysiology. Design principles have been developed to guide medicinal chemistry to enhance absorption, which combine the balance of aqueous solubility, permeability and the sometimes unfavorable compound characteristic demanded by the target. Permeability assays have been implemented that enable rapid development of structure-permeability relationships for absorption improvement. Future advances in assay development to reduce nonspecific binding and improve mass balance will enable more accurately measurement of passive permeability. Design principles that integrate potency, selectivity, passive permeability and other ADMET properties facilitate rapid advancement of successful drug candidates to patients.


Assuntos
Permeabilidade da Membrana Celular , Membrana Celular/metabolismo , Preparações Farmacêuticas/metabolismo , Animais , Encéfalo/metabolismo , Linhagem Celular Tumoral , Humanos , Absorção Intestinal , Mucosa Intestinal/metabolismo , Rim/metabolismo , Fígado/metabolismo , Farmacocinética
7.
Oxid Med Cell Longev ; 2019: 1523140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31214275

RESUMO

Recently, metabolic syndrome (MS) has gained attention in human and animal metabolic medicine. Insulin resistance, inflammation, hyperleptinemia, and hyperinsulinemia are critical to its definition. MS is a complex cluster of metabolic risk factors that together exert a wide range of effects on multiple organs, tissues, and cells in the body. Adipose stem cells (ASCs) are multipotent stem cell population residing within the adipose tissue that is inflamed during MS. Studies have indicated that these cells lose their stemness and multipotency during MS, which strongly reduces their therapeutic potential. They suffer from oxidative stress, apoptosis, and mitochondrial deterioration. Thus, the aim of this study was to rejuvenate these cells in vitro in order to improve their chondrogenic differentiation effectiveness. Pharmacotherapy of ASCs was based on resveratrol and 5-azacytidine pretreatment. We evaluated whether those substances are able to reverse aged phenotype of metabolic syndrome-derived ASCs and improve their chondrogenic differentiation at its early stage using immunofluorescence, transmission and scanning electron microscopy, real-time PCR, and flow cytometry. Obtained results indicated that 5-azacytidine and resveratrol modulated mitochondrial dynamics, autophagy, and ER stress, leading to the enhancement of chondrogenesis in metabolically impaired ASCs. Therefore, pretreatment of these cells with 5-azacytidine and resveratrol may become a necessary intervention before clinical application of these cells in order to strengthen their multipotency and therapeutic potential.


Assuntos
Autofagia/efeitos dos fármacos , Azacitidina/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/patologia , Síndrome Metabólica/fisiopatologia , Mitocôndrias/metabolismo , Resveratrol/farmacologia , Tecido Adiposo/citologia , Animais , Diferenciação Celular , Autorrenovação Celular , Células Cultivadas , Condrogênese , Feminino , Citometria de Fluxo , Doenças dos Cavalos , Cavalos , Humanos , Masculino , Síndrome Metabólica/terapia , Microscopia Eletrônica , Nicho de Células-Tronco
8.
Drug Metab Dispos ; 47(3): 215-226, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30593544

RESUMO

In the present study, the beagle dog was evaluated as a preclinical model to investigate organic anion transporting polypeptide (OATP)-mediated hepatic clearance. In vitro studies were performed with nine OATP substrates in three lots of plated male dog hepatocytes ± OATP inhibitor cocktail to determine total uptake clearance (CLuptake) and total and unbound cell-to-medium concentration ratio (Kpuu). In vivo intrinsic hepatic clearances (CLint,H) were determined following intravenous drug administration (0.1 mg/kg) in male beagle dogs. The in vitro parameters were compared with those previously reported in plated human, monkey, and rat hepatocytes; the ability of cross-species scaling factors to improve prediction of human in vivo clearance was assessed. CLuptake in dog hepatocytes ranged from 9.4 to 135 µl/min/106 cells for fexofenadine and telmisartan, respectively. Active process contributed >75% to CLuptake for 5/9 drugs. Rosuvastatin and valsartan showed Kpuu > 10, whereas cerivastatin, pitavastatin, repaglinide, and telmisartan had Kpuu < 5. The extent of hepatocellular binding in dog was consistent with other preclinical species and humans. The bias (2.73-fold) obtained from comparison of predicted versus in vivo dog CLint,H was applied as an average empirical scaling factor (ESFav) for in vitro-in vivo extrapolation of human CLint,H The ESFav based on dog reduced underprediction of human CLint,H for the same data set (geometric mean fold error = 2.1), highlighting its utility as a preclinical model to investigate OATP-mediated uptake. The ESFav from all preclinical species resulted in comparable improvement of human clearance prediction, in contrast to drug-specific empirical scalars, rationalized by species differences in expression and/or relative contribution of particular transporters to drug hepatic uptake.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Taxa de Depuração Metabólica , Transportadores de Ânions Orgânicos/metabolismo , Preparações Farmacêuticas/metabolismo , Especificidade da Espécie , Animais , Cães , Hepatócitos/metabolismo , Humanos , Infusões Intravenosas , Fígado/citologia , Fígado/metabolismo , Masculino , Modelos Animais , Modelos Biológicos , Preparações Farmacêuticas/administração & dosagem
9.
Pol J Vet Sci ; 21(2): 307-316, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30450870

RESUMO

One of the most common reasons for horse lameness is subchondral bone cysts (SBCs), which are especially evident in young horse athletes. It is believed that SBC development is strongly associated with an individual's bone growth and/or bone microstructure impairment. Current methods of SBC treatment include pharmacological treatment or surgical procedures which may allow the bone within the cyst to rebuild and be restored to properly developed bone tissue. Thus, we propose filling the SBCs with a 3D complex of alginate hydrogel and autologous adipose derived mesenchymal stem cells (ASCs). We have observed at the in vitro level, that this hydrogel complex induces osteogenic and chondrogenic differentiation potential through the upregulation of bone morphogenetic protein, osteopontin, collagen type I and aggrecan mRNA levels. Moreover, we detected the creation of a 3D extracellular matrix (EM). To investigate the complex in vivo, we chose 8 horses of varying age suffering from SBC, which resulted in lameness, to undergo experimental surgery. We documented the horses' clinical appearance, lameness and radiographic appearance, to determine that there was clinical improvement in 87.75% of the patients (n=7, out of 8 horses) 6 months postoperatively and 100% (n=8, out of 8 horses) a year after surgery. These results are promising for the potential of this procedure to become the standard in SBC treatment.


Assuntos
Alginatos , Cistos Ósseos , Doenças dos Cavalos , Transplante de Células-Tronco , Animais , Cistos Ósseos/terapia , Doenças dos Cavalos/terapia , Cavalos , Hidrogéis , Transplante de Células-Tronco/veterinária , Células-Tronco
10.
Radiology ; 287(3): 795-804, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29714681

RESUMO

Purpose To quantify the burden and distribution of asymptomatic atherosclerosis in a population with a low to intermediate risk of cardiovascular disease. Materials and Methods Between June 2008 and February 2013, 1528 participants with 10-year risk of cardiovascular disease less than 20% were prospectively enrolled. They underwent whole-body magnetic resonance (MR) angiography at 3.0 T by using a two-injection, four-station acquisition technique. Thirty-one arterial segments were scored according to maximum stenosis. Scores were summed and normalized for the number of assessable arterial segments to provide a standardized atheroma score (SAS). Multiple linear regression was performed to assess effects of risk factors on atheroma burden. Results A total of 1513 participants (577 [37.9%] men; median age, 53.5 years; range, 40-83 years) completed the study protocol. Among 46 903 potentially analyzable segments, 46 601 (99.4%) were interpretable. Among these, 2468 segments (5%) demonstrated stenoses, of which 1649 (3.5%) showed stenosis less than 50% and 484 (1.0%) showed stenosis greater than or equal to 50%. Vascular stenoses were distributed throughout the body with no localized distribution. Seven hundred forty-seven (49.4%) participants had at least one stenotic vessel, and 408 (27.0%) participants had multiple stenotic vessels. At multivariable linear regression, SAS correlated with age (B = 3.4; 95% confidence interval: 2.61, 4.20), heart rate (B = 1.23; 95% confidence interval: 0.51, 1.95), systolic blood pressure (B = 0.02; 95% confidence interval: 0.01, 0.03), smoking status (B = 0.79; 95% confidence interval: 0.44, 1.15), and socioeconomic status (B = -0.06; 95% confidence interval: -0.10, -0.02) (P < .01 for all). Conclusion Whole-body MR angiography identifies early vascular disease at a population level. Although disease prevalence is low on a per-vessel level, vascular disease is common on a per-participant level, even in this low- to intermediate-risk cohort. © RSNA, 2018 Online supplemental material is available for this article.


Assuntos
Aterosclerose/diagnóstico por imagem , Aterosclerose/epidemiologia , Angiografia por Ressonância Magnética/métodos , Imagem Corporal Total/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Risco , Escócia/epidemiologia
11.
Drug Metab Dispos ; 46(7): 989-1000, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29720472

RESUMO

This work explores the utility of the cynomolgus monkey as a preclinical model to predict hepatic uptake clearance mediated by organic anion transporting polypeptide (OATP) transporters. Nine OATP substrates (rosuvastatin, pravastatin, repaglinide, fexofenadine, cerivastatin, telmisartan, pitavastatin, bosentan, and valsartan) were investigated in plated cynomolgus monkey and human hepatocytes. Total uptake clearance and passive diffusion were measured in vitro from initial rates in the absence and presence of the OATP inhibitor rifamycin SV , respectively. Total uptake clearance values in plated hepatocytes ranged over three orders of magnitude in both species, with a similar rank order and good agreement in the relative contribution of active transport to total uptake between cynomolgus monkey and human. In vivo hepatic clearance for these nine drugs was determined in cynomolgus monkey after intravenous dosing. Hepatic clearances showed a range similar to human parameters and good predictions from respective hepatocyte parameters (with 2.7- and 3.8-fold bias on average, respectively). The use of cross-species empirical scaling factors (determined from cynomolgus monkey data either as the data set average or individual drug values) improved prediction (less bias, better concordance) of human hepatic clearance from human hepatocyte data alone. In vitro intracellular binding in hepatocytes also correlated well between species. It is concluded that the minimal species differences observed for the current data set between cynomolgus monkey and human hepatocyte uptake, both in vitro and in vivo, support future use of this preclinical model to delineate drug hepatic uptake and enable prediction of human in vivo intrinsic hepatic clearance.


Assuntos
Hepatócitos/metabolismo , Fígado/metabolismo , Taxa de Depuração Metabólica/fisiologia , Transportadores de Ânions Orgânicos/metabolismo , Preparações Farmacêuticas/metabolismo , Adulto , Animais , Transporte Biológico/fisiologia , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/metabolismo , Cinética , Macaca fascicularis , Peptídeos/metabolismo
12.
J Pharmacol Exp Ther ; 365(3): 688-699, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29643253

RESUMO

Hepatic organic anion-transporting polypeptides (OATP) 1B1 and 1B3 are clinically relevant transporters associated with significant drug-drug interactions (DDIs) and safety concerns. Given that OATP1Bs in cynomolgus monkey share >90% degree of gene and amino acid sequence homology with human orthologs, we evaluated the in vitro-in vivo translation of OATP1B-mediated DDI risk using this preclinical model. In vitro studies using plated cynomolgus monkey hepatocytes showed active uptake Km values of 2.0 and 3.9 µM for OATP1B probe substrates, pitavastatin and rosuvastatin, respectively. Rifampicin inhibited pitavastatin and rosuvastatin active uptake in monkey hepatocytes with IC50 values of 3.0 and 0.54 µM, respectively, following preincubation with the inhibitor. Intravenous pharmacokinetics of 2H4-pitavastatin and 2H6-rosuvastatin (0.2 mg/kg) and the oral pharmacokinetics of cold probes (2 mg/kg) were studied in cynomolgus monkeys (n = 4) without or with coadministration of single oral ascending doses of rifampicin (1, 3, 10, and 30 mg/kg). A rifampicin dose-dependent reduction in i.v. clearance of statins was observed. Additionally, oral pitavastatin and rosuvastatin plasma exposure increased up to 19- and 15-fold at the highest dose of rifampicin, respectively. Use of in vitro IC50 obtained following 1 hour preincubation with rifampicin (0.54 µM) predicted correctly the change in mean i.v. clearance and oral exposure of statins as a function of mean unbound maximum plasma concentration of rifampicin. This study demonstrates quantitative translation of in vitro OATP1B IC50 to predict DDIs using cynomolgus monkey as a preclinical model and provides further confidence in application of in vitro hepatocyte data for the prediction of clinical OATP1B-mediated DDIs.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Transportador 1 de Ânion Orgânico Específico do Fígado/metabolismo , Quinolinas/farmacologia , Rosuvastatina Cálcica/farmacologia , Administração Oral , Animais , Transporte Biológico , Relação Dose-Resposta a Droga , Interações Medicamentosas , Células HEK293 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacocinética , Macaca fascicularis , Masculino , Quinolinas/administração & dosagem , Quinolinas/metabolismo , Quinolinas/farmacocinética , Rosuvastatina Cálcica/administração & dosagem , Rosuvastatina Cálcica/metabolismo , Rosuvastatina Cálcica/farmacocinética , Distribuição Tecidual
13.
Psychol Med ; 48(10): 1634-1643, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29048273

RESUMO

BACKGROUND: Prior research has typically found a negative relationship between chronic pain and memory, and we examined whether cognitive control processes (e.g. reflection and rumination) moderated this relationship in individuals with Chiari malformation Type I (CM). CM is a neurological condition in which the cerebellar tonsils descend into the medullary and upper cervical spine regions potentially resulting in severe headaches and neck pain. METHODS: CM patients who had (n = 341) and had not (n = 297) undergone decompression surgery completed the McGill Pain Questionnaire-Short Form-Revised (SF-MPQ-2), the Rey Auditory Verbal Learning Test (RAVLT), and the Rumination-Reflection Questionnaire (RRQ). Immediate recall scores were compared to those of 102 healthy controls, and delayed recall performance was compared across other variables within the CM group. RESULTS: CM patients performed more poorly on immediate recall than did controls. Within CM patients, we observed main effects for reflection and age, and a pain x reflection x surgical status (surgery v. no surgery) interaction in which non-decompressed individuals with low levels of pain and high levels of reflection showed superior delayed recall relative to non-decompressed individuals with higher pain and all decompressed individuals. CONCLUSIONS: CM patients show an immediate recall deficit relative to controls, regardless of surgical status. High levels of reflection were associated with better delayed recall performance in non-decompressed CM patients with lower pain levels. High levels of chronic pain may overwhelm increased focused attention abilities, but higher levels of reflection partially overcome the distracting effects of pain and this may represent a type of resilience.


Assuntos
Malformação de Arnold-Chiari/fisiopatologia , Malformação de Arnold-Chiari/cirurgia , Atenção/fisiologia , Dor Crônica/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Memória de Curto Prazo/fisiologia , Rememoração Mental/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Sistema de Registros , Ruminação Cognitiva/fisiologia , Adulto , Malformação de Arnold-Chiari/complicações , Dor Crônica/etiologia , Disfunção Cognitiva/etiologia , Descompressão Cirúrgica , Feminino , Humanos , Masculino
15.
Eur Radiol ; 27(1): 315-324, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27053260

RESUMO

OBJECTIVES: Left ventricular mass (LVM) at cardiac magnetic resonance imaging (CMR) is a frequent end point in clinical trials in nephrology. Trial participants with end stage renal disease (ESRD) may have a greater frequency of incidental findings (IF). We retrospectively investigated prevalence of IF in previous research CMR and reviewed their subsequent impact on participants. METHODS: Between 2002 and 2006, 161 ESRD patients underwent CMR in a transplant assessment study. Images were used to assess LV mass and function. In the current study a radiologist reviewed the scans for IF. Review of patient records determined the subsequent clinical significance of IF. RESULTS: There were 150 IF in 95 study participants. Eighty-four (56 %) were new diagnoses. One hundred and two were non-cardiac. Fifteen were suspicious of malignancy. There was a clinically significant IF for 14.9 % of the participants. In six cases earlier identification of an IF may have improved quality of life or survival. CONCLUSIONS: Without radiology support clinically important IF may be missed on CMR. Patients undergoing CMR in trials should be counselled about the frequency and implications of IF. Patients with ESRD have a higher prevalence of IF than reported in other populations. Nephrology studies require mechanisms for radiologist reporting and strategies for dealing with IF. KEY POINTS: • Incidental findings on research cardiac magnetic resonance imaging can have significant consequences. • We considered incidental findings in historical renal cardiac resonance imaging clinical trials. • Incidental findings are common and important in the chronic kidney disease population. • Without radiology support, clinically significant incidental findings may be missed on imaging. • Study protocols, approvals and consent processes should take account of possible findings.


Assuntos
Cardiopatias/complicações , Cardiopatias/diagnóstico por imagem , Achados Incidentais , Falência Renal Crônica/complicações , Falência Renal Crônica/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Feminino , Coração/diagnóstico por imagem , Cardiopatias/patologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Prevalência , Estudos Retrospectivos
16.
Minim Invasive Ther Allied Technol ; 26(1): 31-38, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27564687

RESUMO

This study presents a framework for workflow optimisation of multimodal image-guided procedures (MIGP) based on discrete event simulation (DES). A case of a combined X-Ray and magnetic resonance image-guided transarterial chemoembolisation (TACE) is presented to illustrate the application of this method. We used a ranking and selection optimisation algorithm to measure the performance of a number of proposed alternatives to improve a current scenario. A DES model was implemented with detail data collected from 59 TACE procedures and durations of magnetic resonance imaging (MRI) diagnostic procedures usually performed in a common MRI suite. Fourteen alternatives were proposed and assessed to minimise the waiting times and improve workflow. Data analysis observed an average of 20.68 (7.68) min of waiting between angiography and MRI for TACE patients in 71.19% of the cases. Following the optimisation analysis, an alternative was identified to reduce waiting times in angiography suite up to 48.74%. The model helped to understand and detect 'bottlenecks' during multimodal TACE procedures, identifying a better alternative to the current workflow and reducing waiting times. Simulation-based workflow analysis provides a cost-effective way to face some of the challenges of introducing MIGP in clinical radiology, highligthed in this study.


Assuntos
Quimioembolização Terapêutica/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Imagem Multimodal/métodos , Radiografia Intervencionista/métodos , Fluxo de Trabalho , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Estudos Retrospectivos , Fatores de Tempo
17.
J Magn Reson Imaging ; 44(5): 1186-1196, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27143317

RESUMO

PURPOSE: To scan a volunteer population using 3.0T magnetic resonance imaging (MRI). MRI of the left ventricular (LV) structure and function in healthy volunteers has been reported extensively at 1.5T. MATERIALS AND METHODS: A population of 1528 volunteers was scanned. A standardized approach was taken to acquire steady-state free precession (SSFP) LV data in the short-axis plane, and images were quantified using commercial software. Six observers undertook the segmentation analysis. RESULTS: Mean values (±standard deviation, SD) were: ejection fraction (EF) = 69 ± 6%, end diastolic volume index (EDVI) = 71 ± 13 ml/m2 , end systolic volume index (ESVI) = 22 ± 7 ml/m2 , stroke volume index (SVI) = 49 ± 8 ml/m2 , and LV mass index (LVMI) = 55 ± 12 g/m2 . The mean EF was slightly larger for females (69%) than for males (68%), but all other variables were smaller for females (EDVI 68v77 ml/m2 , ESVI 21v25 ml/m2 , SVI 46v52 ml/m2 , LVMI 49v64 g/m2 , all P < 0.05). The mean LV volume data mostly decreased with each age decade (EDVI males: -2.9 ± 1.3 ml/m2 , females: -3.1 ± 0.8 ml/m2 ; ESVI males: -1.3 ± 0.7 ml/m2 , females: -1.7 ± 0.5 ml/m2 ; SVI males: -1.7 ± 0.9 ml/m2 , females: -1.4 ± 0.6 ml/m2 ; LVMI males: -1.6 ± 1.1 g/m2 , females: -0.2 ± 0.6 g/m2 ) but the mean EF was virtually stable in males (0.6 ± 0.6%) and rose slightly in females (1.2 ± 0.5%) with age. CONCLUSION: LV reference ranges are provided in this population-based MR study at 3.0T. The variables are similar to those described at 1.5T, including variations with age and gender. These data may help to support future population-based MR research studies that involve the use of 3.0T MRI scanners. J. Magn. Reson. Imaging 2016;44:1186-1196.


Assuntos
Envelhecimento/patologia , Envelhecimento/fisiologia , Ventrículos do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Ventrículos do Coração/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Valores de Referência , Distribuição por Sexo , Fatores Sexuais , Reino Unido/epidemiologia
18.
BMC Med Imaging ; 16: 18, 2016 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-26923316

RESUMO

BACKGROUND: The aim of this study was to use whole body cardiovascular magnetic resonance imaging (WB CVMR) to assess the heart and arterial network in a single examination, so as to describe the burden of atherosclerosis and subclinical disease in participants with symptomatic single site vascular disease. METHODS: 64 patients with a history of symptomatic single site vascular disease (38 coronary artery disease (CAD), 9 cerebrovascular disease, 17 peripheral arterial disease (PAD)) underwent whole body angiogram and cardiac MR in a 3 T scanner. The arterial tree was subdivided into 31 segments and each scored according to the degree of stenosis. From this a standardised atheroma score (SAS) was calculated. Cine and late gadolinium enhancement images of the left ventricle were obtained. RESULTS: Asymptomatic atherosclerotic disease with greater than 50% stenosis in arteries other than that responsible for their presenting complain was detected in 37% of CAD, 33% of cerebrovascular and 47% of PAD patients. Unrecognised myocardial infarcts were observed in 29% of PAD patients. SAS was significantly higher in PAD patients 24 (17.5-30.5) compared to CAD 4 (2-11.25) or cerebrovascular disease patients 6 (2-10) (ANCOVA p < 0.001). Standardised atheroma score positively correlated with age (ß 0.36 p = 0.002), smoking status (ß 0.34 p = 0.002), and LV mass (ß -0.61 p = 0.001) on multiple linear regression. CONCLUSION: WB CVMR is an effective method for the stratification of cardiovascular disease. The high prevalence of asymptomatic arterial disease, and silent myocardial infarctions, particularly in the peripheral arterial disease group, demonstrates the importance of a systematic approach to the assessment of cardiovascular disease.


Assuntos
Aterosclerose/diagnóstico , Doenças Cardiovasculares/complicações , Imageamento por Ressonância Magnética/métodos , Imagem Corporal Total/métodos , Fatores Etários , Idoso , Aterosclerose/epidemiologia , Doenças Cardiovasculares/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco
19.
Ann Vasc Surg ; 32: 1-4, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26806240

RESUMO

BACKGROUND: The fistula first initiative has promoted arteriovenous fistulas (AVFs) as the vascular access of choice. To preserve as many future access options as possible, multiple guidelines advocate that the most distal AVF possible should be created in the first place. Generally, snuff box and radiocephalic (RC) are accepted and well-described sites for AVFs; however, the forearm ulnar-basilic (UB) AVF is seldom used or recommended. The aim of this study is to assess and systematically review the evidence base for the creation of the UB fistula and to critically appraise whether more attention should be given to this site. METHODS: Electronic databases were searched for studies involving the creation of UB fistulas for dialysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The primary outcomes for this study were 1-year primary and secondary patency rates. Secondary outcomes were rates of hemodialysis access-induced distal ischemia (HAIDI) and infection. RESULTS: After strict inclusion and/or exclusion criteria by 2 reviewers, 8 studies were included in our review. Weighted-pooled data reveal 1-year primary patency rate for UB AVFs of 53.0% (95% confidence interval [CI]: 40.1-65.8%) with a secondary patency rate of 72.0% (95% CI: 59.2-83.3). HAIDI and infection rates were low. CONCLUSIONS: Our review has shown that the UB AVF may be a viable alternative when a RC AVF is not possible, and dialysis is not required urgently. It has adequate 1-year primary and secondary patency rates and extremely low risk of HAIDI. While it may be more challenging for both surgeons and dialysis nurses to make it a successful vascular access it offers a further option of distal access which may be overlooked.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Diálise Renal , Insuficiência Renal Crônica/terapia , Artéria Ulnar/cirurgia , Extremidade Superior/irrigação sanguínea , Veias/cirurgia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Humanos , Isquemia/etiologia , Insuficiência Renal Crônica/diagnóstico , Infecção da Ferida Cirúrgica/etiologia , Resultado do Tratamento , Artéria Ulnar/fisiopatologia , Grau de Desobstrução Vascular , Veias/fisiopatologia
20.
J Vasc Access ; 17(1): 40-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26349875

RESUMO

PURPOSE: Haemodialysis access-induced distal ischaemia (HAIDI) is a significant complication of vascular access creation, and has traditionally been difficult to manage without loss of access. Current treatment options include ligation, banding, distal revascularisation with interval ligation (DRIL), proximalisation of the arterial inflow (PAI) and revision using distal flow (RUDI). The purpose of this review was to evaluate the effectiveness of the different surgical techniques in the treatment of HAIDI. METHODS: Electronic databases were searched for studies assessing surgical techniques in the treatment of HAIDI in accordance with PRISMA. The primary outcome for the study was symptomatic relief for each technique, defined within each study. Secondary outcomes included comparison of early thrombosis rates following each different procedure. RESULTS: Following strict inclusion/exclusion criteria by two reviewers, twenty-seven studies of surgical interventions were included and divided into subgroups for banding, DRIL, PAI and RUDI procedures. Both DRIL and banding procedures were found to have high rates of symptomatic relief. In addition, the DRIL has a significantly lower rate of early thrombosis than banding although the more recent papers seem to suggest that early thrombosis is less of a problem in banding. PAI and RUDI showed some promise but there were too few studies to be able to make any clear conclusions. CONCLUSIONS: All four procedures have high success rate in relieving ischaemic symptoms with the DRIL procedure having a significantly better vascular access patency rate than other techniques, although further well designed studies are required to compare all four surgical techniques.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares , Oclusão de Enxerto Vascular/cirurgia , Isquemia/cirurgia , Diálise Renal , Procedimentos Endovasculares/efeitos adversos , Oclusão de Enxerto Vascular/diagnóstico , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Isquemia/diagnóstico , Isquemia/etiologia , Isquemia/fisiopatologia , Ligadura , Fluxo Sanguíneo Regional , Reoperação , Fatores de Risco , Resultado do Tratamento , Grau de Desobstrução Vascular
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