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1.
Intern Med J ; 47(1): 16-34, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27396268

ABSTRACT

This review evaluated the association between time-to-chemotherapy (TTC) and survival in six priority cancers. A systematic review of the literature was undertaken for papers indexed in the MEDLINE and Cochrane Library databases from the earliest index until April 2014. The methodology used has been published in a separate paper (Guidelines for timely initiation of chemotherapy: a proposed framework for access to medical oncology and haematology cancer clinics and chemotherapy services). The optimal timing of chemotherapy in breast cancer is unclear as available studies are of low quality, report inconsistent results and are limited to the adjuvant setting. However, increased TTC may have a negative prognostic impact, and delays beyond 4 weeks should be avoided. Studies suggest that the optimal timing for initiation of adjuvant chemotherapy for surgically resected colorectal cancer is 4-8 weeks post-surgery. Timing of chemotherapy for metastatic colorectal cancer does not influence survival. There is a paucity of studies to guide the timing of chemotherapy for the treatment of lymphoma and myeloma; no definitive conclusions can be drawn, and clinician discretion should be applied. The optimal timing of chemotherapy in lung cancer is unclear; however, rapid tumour growth and poor disease prognosis suggest that delays should be avoided wherever possible. The optimal timing of chemotherapy in ovarian cancer is unclear as available studies are of low level, report inconsistent results and are limited to the post-surgery setting; however, increased TTC may have a negative prognostic impact; therefore, delays beyond 4 weeks should be avoided.


Subject(s)
Chemotherapy, Adjuvant , Neoplasms/drug therapy , Time-to-Treatment , Humans , Neoplasms/classification , Quality Indicators, Health Care , Randomized Controlled Trials as Topic
2.
Food Chem ; 132(1): 613-8, 2012 May 01.
Article in English | MEDLINE | ID: mdl-26434339

ABSTRACT

The potential of solid-phase microextraction on polyacrylate coated fibre, with sequential or simultaneous trimethylsilyl derivatisation followed by gas chromatographic-mass spectrometric analysis, was evaluated for a rapid determination of the distribution of the phytosterols in aqueous food matrixes. Influences of different parameters (bis(trimethylsilyl)trifluoro-acetamide and sterol exposure time, sterol concentration and experimental protocol) on the recovery of sterols were investigated to determine optimum conditions which were tested for sterol extraction and analysis from orange juice. Best selectivity, sterol recovery and derivatisation yields were obtained by extraction and simultaneous derivatisation through immersion of the SPME-PA fibre in the orange juice (10min, 65°C) after headspace absorption of BSTFA (30min, 65°C) on the fibre. Nevertheless the method developed cannot be used for quantitative analysis. But the possibility to effect rapid screen of phytosterol containing in complex media have been shown.


Subject(s)
Citrus sinensis/chemistry , Gas Chromatography-Mass Spectrometry/methods , Phytosterols/chemistry , Solid Phase Microextraction/methods , Beverages , Molecular Structure
3.
J Agric Food Chem ; 56(14): 5775-80, 2008 Jul 23.
Article in English | MEDLINE | ID: mdl-18588314

ABSTRACT

The solid-phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) was used for the analysis of phenolic and other aromatic compounds in honey samples from different floral origin. Different parameters affecting the efficiency of the extraction, such as the type of the stationary phase of the fiber, NaCl and acetic acid addition, and extraction time, were optimized for the detection of the maximum number of compounds in the shortest analysis time. A total of 31 compounds were detected, with most of them identified and quantified by GC-MS. The principal component analysis (PCA) was applied to the data matrix; the results allowed for the differentiation between honeydew and nectar honeys on the basis of the salicylic acid concentration. It was found that this acid has a high contribution in the honeydew group (71.2-705.9 microg/100 g of honey) compared to the nectar honey group (0-47.6 microg/100 g of honey). The comparison of data in each honey group enabled us to characterize the floral source of some honeys using some aromatic compounds as markers.


Subject(s)
Gas Chromatography-Mass Spectrometry , Honey/analysis , Odorants/analysis , Phenols/analysis , Honey/classification , Salicylic Acid/analysis
4.
J Chromatogr Sci ; 45(9): 593-9, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17988447

ABSTRACT

The present study reports the investigation of capillary electrophoresis (CE) for the separation of the photosynthetic pigments (chlorophyll derivatives as well as carotenoids) together. Various CE methods, such as micellar electrokinetic chromatography, capillary electrokinetic chromatography, and nonaqueous capillary electrophoresis (NACE) are tested, with coated and uncoated capillary columns to evaluate optimal separation conditions using diode array detection. The effect of different type and composition of organic solvents and surfactants on the separation is discussed. Detection limits are found in the range of 1.14-2.45 ppm. According to the system suitability results, the most effective separation is observed using NACE with Aliquat 336 as cationic surfactant in coated capillary and mixture of MeOH-ACN-THF (5:4:1, v/v/v) as solvent. Quantitative evolution is investigated, and recovery percentage values are found to be 96.7-102%.


Subject(s)
Carotenoids/isolation & purification , Electrophoresis, Capillary/methods , Porphyrins/isolation & purification , Chromatography, Micellar Electrokinetic Capillary/methods , Reproducibility of Results , Sensitivity and Specificity
5.
Chemosphere ; 52(5): 937-42, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12757796

ABSTRACT

The 13(2),17(3)-cyclopheophorbide a enol (CPP) is shown to convert mainly to a approximately 1:1 mixture of (13(2)R/S) chlorophyllones a (Chlone), when chromatographed over silica gel or alumina supports. 15(1)-hydroxychlorophyllonelactone a and some other chlorophyll a related compounds are also tentatively identified as minor transformation products of CPP. This raises the possibility that the chlorophyllones reported in recent sediments may be analytical artifacts from CPP. However, data for the surface sediments from Lake Motte as well as literature data for other contemporary sediments show that, (i) they are not artifacts, (ii) considering that CPP is the intermediate compound in the formation of chlorophyllones from chlorophyll a, the hydroxylation of CPP in the sedimentary environment involves an enzymatic process leading preferentially to 13(2)S chlorophyllone a.


Subject(s)
Geologic Sediments/chemistry , Porphyrins/analysis , Animals , Chromatography, High Pressure Liquid/methods , Environmental Monitoring , Enzymes/metabolism , Hydroxylation , Oxidation-Reduction , Porphyrins/chemistry , Porphyrins/metabolism , Reproducibility of Results , Spectrometry, Mass, Electrospray Ionization/methods , Stereoisomerism , Water Pollutants, Chemical/analysis , Zooplankton
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