Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
Knee Surg Sports Traumatol Arthrosc ; 32(5): 1096-1104, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461373

RESUMO

PURPOSE: To investigate the landing strategies used after discontinuing and continuing the use of a functional knee brace (FKB) while performing a drop jump. METHODS: Following published methodology and power analysis, 23 uninjured male athletes, mean age of 19.4 ± 3.0 years, performed seven tests, during three test conditions (nonbraced, braced and removed brace or continued brace use), over 6 days of 12 testing sessions (S) for a total of 38.5 h. Each subject was provided with a custom-fitted FKB. This study focuses on the single leg drop jump kinetics during S12 when subjects were randomly selected to remove the FKB after 17.5 h or continued use of FKB. The time to peak vertical ground reaction forces (PVGRF) and PVGRF were recorded on landing in eight trials. RESULTS: After brace removal, a significantly shorter mean time to PVGRF was recorded (9.4 ± 22.9 msec (3.9%), p = 0.005, 95% confidence interval (95% CI): -168.1, 36.1), while continued brace use required a nonsignificant (n.s.) longer mean duration to achieve PVGRF (19.4 ± 53.6 msec (8.9%), n.s., 95% CI: -49.7, 73.4). No significant mean PVGRF difference was found in brace removal (25.3 ± 65.8 N) and continued brace use (25.1 ± 23.0 N). CONCLUSION: Removal of FKB after 17.5 h of use led to a significantly shorter time to achieve PVGRF, while continued brace use for 21 h required a longer duration to achieve PVGRF, suggesting faster and slower knee joint loading, respectively. Understanding the concerns associated with the use of FKB and the kinetics of the knee joint will assist clinicians in counselling athletes about the risks and benefits of using an FKB. LEVEL OF EVIDENCE: Level II.


Assuntos
Braquetes , Articulação do Joelho , Humanos , Masculino , Articulação do Joelho/fisiologia , Adulto Jovem , Fenômenos Biomecânicos , Fatores de Tempo , Suporte de Carga , Adolescente , Adulto , Remoção de Dispositivo
2.
J Clin Transl Hepatol ; 11(3): 638-648, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-36969895

RESUMO

Background and Aims: The prevalence of chronic liver disease in adults exceeds 30% in some countries and there is significant interest in developing tests and treatments to help control disease progression and reduce healthcare burden. Breath is a rich sampling matrix that offers non-invasive solutions suitable for early-stage detection and disease monitoring. Having previously investigated targeted analysis of a single biomarker, here we investigated a multiparametric approach to breath testing that would provide more robust and reliable results for clinical use. Methods: To identify candidate biomarkers we compared 46 breath samples from cirrhosis patients and 42 from controls. Collection and analysis used Breath Biopsy OMNI™, maximizing signal and contrast to background to provide high confidence biomarker detection based upon gas chromatography mass spectrometry (GC-MS). Blank samples were also analyzed to provide detailed information on background volatile organic compounds (VOCs) levels. Results: A set of 29 breath VOCs differed significantly between cirrhosis and controls. A classification model based on these VOCs had an area under the curve (AUC) of 0.95±0.04 in cross-validated test sets. The seven best performing VOCs were sufficient to maximize classification performance. A subset of 11 VOCs was correlated with blood metrics of liver function (bilirubin, albumin, prothrombin time) and separated patients by cirrhosis severity using principal component analysis. Conclusions: A set of seven VOCs consisting of previously reported and novel candidates show promise as a panel for liver disease detection and monitoring, showing correlation to disease severity and serum biomarkers at late stage.

3.
Clin Transl Gastroenterol ; 11(9): e00239, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33094960

RESUMO

INTRODUCTION: Liver cirrhosis and its complication - hepatocellular carcinoma (HCC) - have been associated with increased exhaled limonene. It is currently unclear whether this increase is more strongly associated with the presence of HCC or with the severity of liver dysfunction. METHODS: We compared the exhaled breath of 40 controls, 32 cirrhotic patients, and 12 cirrhotic patients with HCC using the Breath Biopsy platform. Breath samples were analyzed by thermal desorption-gas chromatography-mass spectrometry. Limonene levels were compared between the groups and correlated to bilirubin, albumin, prothrombin time international normalized ratio, and alanine aminotransferase. RESULTS: Breath limonene concentration was significantly elevated in subjects with cirrhosis-induced HCC (M: 82.1 ng/L, interquartile range [IQR]: 16.33-199.32 ng/L) and cirrhosis (M: 32.6 ng/L, IQR: 6.55-123.07 ng/L) compared with controls (M: 6.2 ng/L, IQR: 2.62-9.57 ng/L) (P value = 0.0005 and 0.0001, respectively) with no significant difference between 2 diseased groups (P value = 0.37). Levels of exhaled limonene correlated with serum bilirubin (R = 0.25, P value = 0.0016, r = 0.51), albumin (R = 0.58, P value = 5.3e-8, r = -0.76), and international normalized ratio (R = 0.29, P value = 0.0003, r = 0.51), but not with alanine aminotransferase (R = 0.01, P value = 0.36, r = 0.19). DISCUSSION: Exhaled limonene levels are primarily affected by the presence of cirrhosis through reduced liver functional capacity, as indicated by limonene correlation with blood metrics of impaired hepatic clearance and protein synthesis capacity, without further alterations observed in subjects with HCC. This suggests that exhaled limonene is a potential non-invasive marker of liver metabolic capacity (see Visual abstract, Supplementary Digital Content 1, http://links.lww.com/CTG/A388).


Assuntos
Carcinoma Hepatocelular/diagnóstico , Limoneno/análise , Cirrose Hepática/diagnóstico , Neoplasias Hepáticas/diagnóstico , Compostos Orgânicos Voláteis/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Testes Respiratórios , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/fisiopatologia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Fígado/patologia , Fígado/fisiopatologia , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Testes de Função Hepática/métodos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença
4.
J Proteome Res ; 18(1): 392-398, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30394759

RESUMO

Modern label-free quantitative mass spectrometry workflows are complex experimental chains for devising the composition of biological samples. With benchtop and in silico experimental steps that each have a significant effect on the accuracy, coverage, and statistical significance of the study result, it is crucial to understand the efficacy and biases of each protocol decision. Although many studies have been conducted on wet lab experimental protocols, postacquisition data processing methods have not been adequately evaluated in large part due to a lack of available ground truth data. In this study, we provide a novel ground truth data set for mass spectrometry data analysis at the precursor (MS1) signal level comprised of isolated peptide signals from UPS2, a popular complex standard for proteomics analysis, requiring more than 1000 h of manual curation. The data set consists of more than 62 million points with 1,294,008 grouped into 57,518 extracted ion chromatograms and those grouped into 14,111 isotopic envelopes. This data set can be used to evaluate many aspects of mass spectrometry data processing, including precursor mapping and signal extraction algorithms.


Assuntos
Algoritmos , Espectrometria de Massas/métodos , Peptídeos/análise , Proteômica/métodos , Curadoria de Dados , Fluxo de Trabalho
5.
Vet Rec ; 181(22): 595-599, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28947678

RESUMO

The objective of this study was to determine the effect on pregnancy outcome of either inseminating heifers twice (at 48 and 72 hours after withdrawal of a controlled internal drug release insert (CIDR) containing progesterone) or once (56 hours after CIDR withdrawal) following a seven-day CIDR synchronisation protocol. Dairy heifers (n=267) from five farms, with an age range of 388-736 days, were randomly assigned to one of two treatment groups (group A heifers were inseminated twice; group B heifers were inseminated once). Both groups received a CIDR on day (D) 0 and an intramuscular injection of d-cloprostenol on D6; the CIDR was withdrawn on D7. Measurements of withers height, body condition score and hearth girth (used to estimate weight) were taken on D0. The diameter of the largest follicles and corpora lutea was recorded on both D0 and D6. Data were analysed with the use of multivariable logistic regression modelling. Treatment group and farm were not statistically significantly associated with pregnancy per treatment (P/T). Age and dominant follicle size on D6 were significantly associated with P/T. Heifers with the largest dominant follicle sizes (16-22 mm) were 5.54 times less likely to be pregnant than those heifers with the smallest dominant follicles (8-10 mm) on D6. It was shown that the cost associated with inseminating heifers twice after a seven-day CIDR synchronisation protocol is not justified.


Assuntos
Inseminação Artificial/veterinária , Resultado da Gravidez/veterinária , Progesterona/administração & dosagem , Animais , Bovinos , Preparações de Ação Retardada , Feminino , Inseminação Artificial/métodos , Gravidez , Fatores de Tempo , Reino Unido
6.
EFSA J ; 15(10): e05007, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32625302

RESUMO

In 2013, EFSA published a comprehensive systematic review of epidemiological studies published from 2006 to 2012 investigating the association between pesticide exposure and many health outcomes. Despite the considerable amount of epidemiological information available, the quality of much of this evidence was rather low and many limitations likely affect the results so firm conclusions cannot be drawn. Studies that do not meet the 'recognised standards' mentioned in the Regulation (EU) No 1107/2009 are thus not suited for risk assessment. In this Scientific Opinion, the EFSA Panel on Plant Protection Products and their residues (PPR Panel) was requested to assess the methodological limitations of pesticide epidemiology studies and found that poor exposure characterisation primarily defined the major limitation. Frequent use of case-control studies as opposed to prospective studies was considered another limitation. Inadequate definition or deficiencies in health outcomes need to be avoided and reporting of findings could be improved in some cases. The PPR Panel proposed recommendations on how to improve the quality and reliability of pesticide epidemiology studies to overcome these limitations and to facilitate an appropriate use for risk assessment. The Panel recommended the conduct of systematic reviews and meta-analysis, where appropriate, of pesticide observational studies as useful methodology to understand the potential hazards of pesticides, exposure scenarios and methods for assessing exposure, exposure-response characterisation and risk characterisation. Finally, the PPR Panel proposed a methodological approach to integrate and weight multiple lines of evidence, including epidemiological data, for pesticide risk assessment. Biological plausibility can contribute to establishing causation.

7.
EFSA J ; 15(3): e04691, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32625422

RESUMO

In 2013, EFSA published a literature review on epidemiological studies linking exposure to pesticides and human health outcome. As a follow up, the EFSA Panel on Plant Protection Products and their residues (PPR Panel) was requested to investigate the plausible involvement of pesticide exposure as a risk factor for Parkinson's disease (PD) and childhood leukaemia (CHL). A systematic literature review on PD and CHL and mode of actions for pesticides was published by EFSA in 2016 and used as background documentation. The Panel used the Adverse Outcome Pathway (AOP) conceptual framework to define the biological plausibility in relation to epidemiological studies by means of identification of specific symptoms of the diseases as AO. The AOP combines multiple information and provides knowledge of biological pathways, highlights species differences and similarities, identifies research needs and supports regulatory decisions. In this context, the AOP approach could help in organising the available experimental knowledge to assess biological plausibility by describing the link between a molecular initiating event (MIE) and the AO through a series of biologically plausible and essential key events (KEs). As the AOP is chemically agnostic, tool chemical compounds were selected to empirically support the response and temporal concordance of the key event relationships (KERs). Three qualitative and one putative AOP were developed by the Panel using the results obtained. The Panel supports the use of the AOP framework to scientifically and transparently explore the biological plausibility of the association between pesticide exposure and human health outcomes, identify data gaps, define a tailored testing strategy and suggests an AOP's informed Integrated Approach for Testing and Assessment (IATA).

8.
Eur J Endocrinol ; 175(5): 485-498, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27562400

RESUMO

OBJECTIVE: To determine if functional imaging using 11C-methionine positron emission tomography co-registered with 3D gradient echo MRI (Met-PET/MRI), can identify sites of residual active tumour in treated acromegaly, and discriminate these from post-treatment change, to allow further targeted treatment. DESIGN/METHODS: Twenty-six patients with persistent acromegaly after previous treatment, in whom MRI appearances were considered indeterminate, were referred to our centre for further evaluation over a 4.5-year period. Met-PET/MRI was performed in each case, and findings were used to decide regarding adjunctive therapy. Four patients with clinical and biochemical remission after transsphenoidal surgery (TSS), but in whom residual tumour was suspected on post-operative MRI, were also studied. RESULTS: Met-PET/MRI demonstrated tracer uptake only within the normal gland in the four patients who had achieved complete remission after primary surgery. In contrast, in 26 patients with active acromegaly, Met-PET/MRI localised sites of abnormal tracer uptake in all but one case. Based on these findings, fourteen subjects underwent endoscopic TSS, leading to a marked improvement in (n = 7), or complete resolution of (n = 7), residual acromegaly. One patient received stereotactic radiosurgery and two patients with cavernous sinus invasion were treated with image-guided fractionated radiotherapy, with good disease control. Three subjects await further intervention. Five patients chose to receive adjunctive medical therapy. Only one patient developed additional pituitary deficits after Met-PET/MRI-guided TSS. CONCLUSIONS: In patients with persistent acromegaly after primary therapy, Met-PET/MRI can help identify the site(s) of residual pituitary adenoma when MRI appearances are inconclusive and direct further targeted intervention (surgery or radiotherapy).

9.
Sci Total Environ ; 537: 159-69, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26318547

RESUMO

Pesticides are regulated in Europe and this process includes an environmental risk assessment (ERA) for non-target arthropods (NTA). Traditionally a non-spatial or field trial assessment is used. In this study we exemplify the introduction of a spatial context to the ERA as well as suggest a way in which the results of complex models, necessary for proper inclusion of spatial aspects in the ERA, can be presented and evaluated easily using abundance and occupancy ratios (AOR). We used an agent-based simulation system and an existing model for a widespread carabid beetle (Bembidion lampros), to evaluate the impact of a fictitious highly-toxic pesticide on population density and the distribution of beetles in time and space. Landscape structure and field margin management were evaluated by comparing scenario-based ERAs for the beetle. Source-sink dynamics led to an off-crop impact even when no pesticide was present off-crop. In addition, the impacts increased with multi-year application of the pesticide whereas current ERA considers only maximally one year. These results further indicated a complex interaction between landscape structure and pesticide effect in time, both in-crop and off-crop, indicating the need for NTA ERA to be conducted at landscape- and multi-season temporal-scales. Use of AOR indices to compare ERA outputs facilitated easy comparison of scenarios, allowing simultaneous evaluation of impacts and planning of mitigation measures. The landscape and population ERA approach also demonstrates that there is a potential to change from regulation of a pesticide in isolation, towards the consideration of pesticide management at landscape scales and provision of biodiversity benefits via inclusion and testing of mitigation measures in authorisation procedures.


Assuntos
Conservação dos Recursos Naturais/métodos , Poluição Ambiental/estatística & dados numéricos , Modelos Teóricos , Praguicidas , Agricultura , Poluição Ambiental/prevenção & controle , Medição de Risco
10.
BMC Bioinformatics ; 16 Suppl 7: S1, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25951936

RESUMO

BACKGROUND: Liquid chromatography-mass spectrometry is a popular technique for high-throughput protein, lipid, and metabolite comparative analysis. Such statistical comparison of millions of data points requires the generation of an inter-run correspondence. Though many techniques for generating this correspondence exist, few if any, address certain well-known run-to-run LC-MS behaviors such as elution order swaps, unbounded retention time swaps, missing data, and significant differences in abundance. Moreover, not all extant correspondence methods leverage the rich discriminating information offered by isotope envelope extraction informed by isotope trace extraction. To date, no attempt has been made to create a formal generalization of extant algorithms for these problems. RESULTS: By enumerating extant objective functions for these problems, we elucidate discrepancies between known LC-MS data behavior and extant approaches. We propose novel objective functions that more closely model known LC-MS behavior. CONCLUSIONS: Through instantiating the proposed objective functions in the form of novel algorithms, practitioners can more accurately capture the known behavior of isotope traces, isotopic envelopes, and replicate LC-MS data, ultimately providing for improved quantitative accuracy.


Assuntos
Algoritmos , Cromatografia Líquida/métodos , Isótopos/química , Espectrometria de Massas/métodos , Modelos Teóricos , Peptídeos/análise , Proteômica/métodos , Humanos , Peptídeos/química
11.
BMC Bioinformatics ; 16 Suppl 7: S2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25952148

RESUMO

BACKGROUND: The comparison of analyte mass spectrometry precursor (MS1) signal is central to many proteomic (and other -omic) workflows. Standard vocabularies for mass spectrometry exist and provide good coverage for most experimental applications yet are insufficient for concise and unambiguous description of data concepts spanning the range of signal provenance from a molecular perspective (e.g. from charged peptides down to fine isotopes). Without a standard unambiguous nomenclature, literature searches, algorithm reproducibility and algorithm evaluation for MS-omics data processing are nearly impossible. RESULTS: We show how terms from current official ontologies are too vague or ambiguous to explicitly map molecular entities to MS signals and we illustrate the inconsistency and ambiguity of current colloquially used terms. We also propose a set of terms for MS1 signal that uniquely, succinctly and intuitively describe data concepts spanning the range of signal provenance from full molecule downs to fine isotopes. We suggest that additional community discussion of these terms should precede any further standardization efforts. We propose a novel nomenclature that spans the range of the required granularity to describe MS data processing from the perspective of the molecular provenance of the MS signal. CONCLUSIONS: The proposed nomenclature provides a chain of succinct and unique terms spanning the signal created by a charged molecule down through each of its constituent subsignals. We suggest that additional community discussion of these terms should precede any further standardization efforts.


Assuntos
Processamento Eletrônico de Dados , Espectrometria de Massas/métodos , Peptídeos/análise , Linguagens de Programação , Proteômica/métodos , Vocabulário Controlado , Humanos , Processamento de Linguagem Natural , Reprodutibilidade dos Testes
12.
EuroIntervention ; 11(5): 511-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24694592

RESUMO

AIMS: We aimed to investigate why many patients with ST-segment elevation myocardial infarction (STEMI) initially present to non-primary percutaneous coronary intervention (PPCI) equipped hospitals in a region that offers a 24-hour direct access Heart Attack Centre. METHODS AND RESULTS: A retrospective stratified consecutive case analysis was performed for 180 inter-hospital transfer (IHT) and 201 direct access PPCI patients. IHT and direct patients had similar age (61±1.8 years vs. 62±1.9 years, p=0.42), gender (76% vs. 78% male, p=0.64), and cardiovascular risk profile (hypertension 53% vs. 46%, p=0.18; hypercholesterolaemia 32% vs. 25%, p=0.22; and smoking 38% vs. 35%, p=0.56), though there were more diabetic patients in the IHT group (15% vs. 8%, p<0.05). The IHT group had longer symptom-call times 104 mins (42 mins-195 mins) vs. 46 mins (19 mins-114 mins), p<0.0001), lower ECG ST-elevation scores (3.0 mm [1.0-6.0] vs. 5.0 mm [3.0-9.0], p<0.0001), and more protocol negative ECGs at presentation (31.6% vs. 9.4%, p<0.0001). Peak CK was similar for the two groups (628 IU/L [191-1,144] vs. 603 IU/L [280-1,238], p=0.61), as was in-hospital (1.7% vs. 1.5%, p=0.89) and 30-day mortality (2.8% vs. 2.0%, p=0.61). CONCLUSIONS: This study suggests that reperfusion delays in PPCI due to IHT are not always simply "system failures". IHT patients appear to be a different patient cohort in which symptoms and early ECG changes may be less clear. In many cases, initial triage to a non-PPCI centre may be justifiable due to diagnostic uncertainty, and guideline time metrics should be amended appropriately.


Assuntos
Angioplastia Coronária com Balão , Hospitais , Infarto do Miocárdio/terapia , Transferência de Pacientes , Tempo para o Tratamento , Eletrocardiografia , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Intervenção Coronária Percutânea , Estudos Retrospectivos , Serviços de Saúde Suburbana , Reino Unido
13.
Brief Bioinform ; 15(5): 768-70, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23894105

RESUMO

As the field of bioinformatics research continues to grow, more and more novel techniques are proposed to meet new challenges and improvements upon solutions to long-standing problems. These include data processing techniques and wet lab protocol techniques. Although the literature is consistently thorough in experimental detail and variable-controlling rigor for wet lab protocol techniques, bioinformatics techniques tend to be less described and less controlled. As the validation or rejection of hypotheses rests on the experiment's ability to isolate and measure a variable of interest, we urge the importance of reducing confounding variables in bioinformatics techniques during mass spectrometry experimentation.


Assuntos
Lipídeos/química , Espectrometria de Massas/métodos , Metabolômica , Proteômica , Biomarcadores Tumorais/sangue , Humanos , Proteínas de Neoplasias/sangue , Neoplasias/diagnóstico
15.
Apoptosis ; 13(11): 1368-77, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18785011

RESUMO

Although numerous studies have shown that certain long chain fatty acids can induce apoptosis in cancer cells, the molecular mechanisms for this phenomenon are still poorly elucidated. The phosphoinositide 3-kinase (PI3-kinase) signaling pathway plays a pivotal role in the regulation of cell growth and can also contribute to tumorigenesis and cancer progression. The aims of the present study were three fold: (i) to investigate the potential chemopreventative/antiproliferative effect of various fatty acids in colon cancer cells (CaCo-2 cells) and normal colon epithelium cells (NCM460 cells); (ii) to investigate the mechanisms by which incubation with various fatty acids influences the PI3-kinase pathway in CaCo-2 cells; and (iii) to evaluate apoptosis in our cell model. Although all the fatty acids increased the viability of normal (NCM460) cells, only docosahexaenoic acid (DHA) significantly reduced cell viability and induced apoptosis in the cancer (CaCo-2) cells. Our results indicate that DHA is an effective chemotherapeutic agent to induce apoptosis in cancer cells and that this effect is mediated by the PI3-kinase signaling pathway.


Assuntos
Apoptose , Colo/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Ácidos Graxos Insaturados/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Sobrevivência Celular , Ácidos Docosa-Hexaenoicos/química , Ácidos Graxos/metabolismo , Humanos , Modelos Biológicos , Fosforilação , Transdução de Sinais
16.
Anticancer Drugs ; 13(6): 645-53, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12172511

RESUMO

ZD9331 is a potent thymidylate synthase inhibitor. Renal and hepatic clearances were found to be important routes of elimination. The objectives of this pharmacologic trial were to investigate the effect of renal impairment on the pharmacokinetics of ZD9331, to study the toxicity profile and to document any antitumor effects of ZD9331 when administered i.v. to patients with different degrees of renal impairment. Patients were treated with ZD9331 130 mg/m2 given as an i.v. infusion on day 1 of a 4-week cycle to allow full pharmacokinetic assessment. Subsequent cycles involved the administration of ZD9331 on days 1 and 8, every 3 weeks. Patients were stratified according to their renal function assessed by the creatinine clearance: normal renal function (creatinine clearance > or =60 ml/min), mildly impaired renal function (creatinine clearance > or =40 to <60 ml/min) and moderately impaired renal function (creatinine clearance >25 to <40 ml/min). For pharmacokinetic analysis plasma sampling was performed during the first course and assayed using a validated liquid chromatographic tandem mass spectrometry assay. Twenty-three patients were entered on the study, of whom 21 received 130 mg/m2 ZD9331 in the first treatment cycle. No relationship was seen between renal impairment and plasma clearance nor with the area under the concentration-time curve of free ZD9331. Increasing renal impairment was associated with a greater incidence of myelosuppression. No predictive relationship between the clearance of free ZD9331 and the degree of renal impairment as determined by creatinine clearance could be assessed. However, data from this trial indicate that increased renal impairment may be associated with greater ZD9331-induced toxicity, particularly myelosuppression, although this cannot be attributed to any alteration in the plasma pharmacokinetics of ZD9331. Therefore, it may be necessary to administer a reduced dose of ZD9331 to patients with impaired renal function.


Assuntos
Antineoplásicos/efeitos adversos , Inibidores Enzimáticos/efeitos adversos , Nefropatias/complicações , Nefropatias/metabolismo , Neoplasias/metabolismo , Quinazolinas/efeitos adversos , Quinazolinas/farmacocinética , Timidilato Sintase/antagonistas & inibidores , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Contagem de Células Sanguíneas , Creatinina/metabolismo , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/uso terapêutico , Feminino , Doenças Hematológicas/sangue , Doenças Hematológicas/induzido quimicamente , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Quinazolinas/administração & dosagem , Quinazolinas/uso terapêutico
17.
J Clin Oncol ; 20(7): 1923-31, 2002 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11919253

RESUMO

PURPOSE: To assess the toxicity profile and dose-limiting toxicities (DLTs), to determine the maximum-tolerated dose, and to study the pharmacokinetics of ZD9331 when administered orally to patients with advanced solid tumors. PATIENTS AND METHODS: Patients were treated with oral ZD9331 given once daily (od) or twice daily (bid) for 5, 7, or 10 days; cycles were repeated every 21 days at doses ranging from 2.5 to 40 mg. For pharmacokinetic analysis, plasma sampling was performed during the first course and assayed using a validated liquid chromatographic-tandem mass spectrometry assay. Plasma levels of 2'-deoxyuridine were measured as a surrogate marker for TS inhibition. RESULTS: Forty-two patients received a total of 166 courses. The DLTs were myelosuppression and skin rash. Dose escalation of oral ZD9331 from 2.5 to 40 mg, as a single daily dose, resulted in a less than proportional increase in the plasma area under the concentration-time curve of ZD9331. The plasma drug exposure per cycle for the schedules 20 mg od for 5 days, 10 mg od for 10 days, and 10 mg bid for 5 days, all resulting in a total dose per cycle of 100 mg, were comparable. One partial response was noted in a patient with gastric cancer. CONCLUSION: DLTs in this phase I study of oral ZD9331 were myelosuppression and skin toxicity. The recommended dose for phase II studies of oral ZD9331 is 20 mg od for 5 consecutive days, every 3 weeks.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Medula Óssea/efeitos dos fármacos , Toxidermias/etiologia , Neoplasias/tratamento farmacológico , Quinazolinas/administração & dosagem , Quinazolinas/efeitos adversos , Timidilato Sintase/antagonistas & inibidores , Administração Oral , Adulto , Idoso , Antineoplásicos/química , Antineoplásicos/farmacocinética , Área Sob a Curva , Cromatografia Líquida , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Neoplasias/sangue , Quinazolinas/química , Quinazolinas/farmacocinética , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA