46 research outputs found

    Daily intake of antioxidants in relation to survival among adult patients diagnosed with malignant glioma

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    <p>Abstract</p> <p>Background</p> <p>Malignant glioma is a rare cancer with poor survival. The influence of diet and antioxidant intake on glioma survival is not well understood. The current study examines the association between antioxidant intake and survival after glioma diagnosis.</p> <p>Methods</p> <p>Adult patients diagnosed with malignant glioma during 1991-1994 and 1997-2001 were enrolled in a population-based study. Diagnosis was confirmed by review of pathology specimens. A modified food-frequency questionnaire interview was completed by each glioma patient or a designated proxy. Intake of each food item was converted to grams consumed/day. From this nutrient database, 16 antioxidants, calcium, a total antioxidant index and 3 macronutrients were available for survival analysis. Cox regression estimated mortality hazard ratios associated with each nutrient and the antioxidant index adjusting for potential confounders. Nutrient values were categorized into tertiles. Models were stratified by histology (Grades II, III, and IV) and conducted for all (including proxy) subjects and for a subset of self-reported subjects.</p> <p>Results</p> <p>Geometric mean values for 11 fat-soluble and 6 water-soluble individual antioxidants, antioxidant index and 3 macronutrients were virtually the same when comparing all cases (n = 748) to self-reported cases only (n = 450). For patients diagnosed with Grade II and Grade III histology, moderate (915.8-2118.3 mcg) intake of fat-soluble lycopene was associated with poorer survival when compared to low intake (0.0-914.8 mcg), for self-reported cases only. High intake of vitamin E and moderate/high intake of secoisolariciresinol among Grade III patients indicated greater survival for all cases. In Grade IV patients, moderate/high intake of cryptoxanthin and high intake of secoisolariciresinol were associated with poorer survival among all cases. Among Grade II patients, moderate intake of water-soluble folate was associated with greater survival for all cases; high intake of vitamin C and genistein and the highest level of the antioxidant index were associated with poorer survival for all cases.</p> <p>Conclusions</p> <p>The associations observed in our study suggest that the influence of some antioxidants on survival following a diagnosis of malignant glioma are inconsistent and vary by histology group. Further research in a large sample of glioma patients is needed to confirm/refute our results.</p

    Molecular Phylogeny of the Astrophorida (Porifera, Demospongiaep) Reveals an Unexpected High Level of Spicule Homoplasy

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    Background: The Astrophorida (Porifera, Demospongiae(rho)) is geographically and bathymetrically widely distributed. Systema Porifera currently includes five families in this order: Ancorinidae, Calthropellidae, Geodiidae, Pachastrellidae and Thrombidae. To date, molecular phylogenetic studies including Astrophorida species are scarce and offer limited sampling. Phylogenetic relationships within this order are therefore for the most part unknown and hypotheses based on morphology largely untested. Astrophorida taxa have very diverse spicule sets that make them a model of choice to investigate spicule evolution. Methodology/Principal Findings: With a sampling of 153 specimens (9 families, 29 genera, 89 species) covering the deep- and shallow-waters worldwide, this work presents the first comprehensive molecular phylogeny of the Astrophorida, using a cytochrome c oxidase subunit I (COI) gene partial sequence and the 59 end terminal part of the 28S rDNA gene (C1-D2 domains). The resulting tree suggested that i) the Astrophorida included some lithistid families and some Alectonidae species, ii) the sub-orders Euastrophorida and Streptosclerophorida were both polyphyletic, iii) the Geodiidae, the Ancorinidae and the Pachastrellidae were not monophyletic, iv) the Calthropellidae was part of the Geodiidae clade (Calthropella at least), and finally that v) many genera were polyphyletic (Ecionemia, Erylus, Poecillastra, Penares, Rhabdastrella, Stelletta and Vulcanella). Conclusion: The Astrophorida is a larger order than previously considered, comprising ca. 820 species. Based on these results, we propose new classifications for the Astrophorida using both the classical rank-based nomenclature (i.e., Linnaean classification) and the phylogenetic nomenclature following the PhyloCode, independent of taxonomic rank. A key to the Astrophorida families, sub-families and genera incertae sedis is also included. Incongruences between our molecular tree and the current classification can be explained by the banality of convergent evolution and secondary loss in spicule evolution. These processes have taken place many times, in all the major clades, for megascleres and microscleres

    Dose-banding of intravenous piperacillin-tazobactam in pediatric surgical inpatients

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    © Published by the Pediatric Pharmacy Advocacy Group. All rights reserved. BACKGROUND Antimicrobial doses in children are often prescribed by using an individually calculated dose per weight (e.g., mg/kg) or based on body surface area. Dosing errors are the most commonly reported medication errors in children. A “dose-banding” strategy is frequently used for some over-the-counter drugs to prevent dosing errors. It could also lead to efficiencies by enabling batch preparation of intravenous (IV) medications in hospitals. OBJECTIVES To evaluate whether use of dose-banding for IV piperacillin-tazobactam results in acceptable dose variation from standard practice of individualized prescription of 100 mg/kg in children. METHODS We conducted a historically controlled intervention study comparing prescriptions of IV piperacillin-tazobactam before vs. after introduction of dose-banding prescribing guidance for surgical inpatients weighing &gt; 5 kg and &lt; 16 years of age at the tertiary referral pediatric hospital in Western Australia. RESULTS Dose-banding of IV piperacillin-tazobactam (with a maximum of 15% departure from the recommended milligram-per-weight dose of 100 mg/kg) resulted in similar overall variation of prescribed dose in comparison to individualized milligram-per-weight (non-dose-banded) prescribing. There was a trend toward fewer prescriptions with large variance ( &gt; 30% variation from the 100-mg/kg dose) in the dose-banded compared to the non-dose-banded group (1/140 vs. 5/105; p = 0.09). CONCLUSIONS Our study showed dose-banding of IV piperacillin-tazobactam resulted in acceptable variation when compared to individualized milligram-per-weight dosing in children. Prospectively designed controlled trials are warranted to determine whether dose-banding could reduce medication errors and optimize use of hospital resources. Implications for future practice could include faster batch preparation, shorter checking and dispensing time, and reduction in drug wastage

    Dose banding as an alternative to body surface area-based dosing of chemotherapeutic agents

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    BACKGROUND: Dose banding is a recently suggested dosing method that uses predefined ranges (bands) of body surface area (BSA) to calculate each patient's dose by using a single BSA-value per band. Thus, drugs with sufficient long-term stability can be prepared in advance. The main advantages of dose banding are to reduce patient waiting time and improve pharmacy capacity planning; additional benefits include reduced medication errors, reduced drug wastage, and prospective quality control. This study compares dose banding with individual BSA dosing and fixed dose according to pharmacokinetic criteria. METHODS: Three BSA bands were defined: BSA<1.7 m(2), 1.7 m(2)⩽BSA<1.9 m(2), BSA⩾1.9 m(2) and each patient dose was calculated based on a unique BSA-value per band (1.55, 1.80, and 2.05 m(2), respectively). By using individual clearance values of six drugs (cisplatin, docetaxel, paclitaxel, doxorubicin, irinotecan, and topotecan) from 1012 adult cancer patients in total, the AUCs corresponding to three dosing methods (BSA dosing, dose banding, and fixed dose) were compared with a target AUC for each drug. RESULTS: For all six drugs, the per cent variation in individual dose obtained with dose banding compared with BSA dosing ranged between −14% and +22%, and distribution of AUC values was very similar with both dosing methods. In terms of reaching the target AUC, there was no significant difference in precision between dose banding and BSA dosing, except for paclitaxel (32.0% vs 30.7%, respectively; P<0.05). However, precision was significantly better for BSA dosing compared with fixed dose for four out of six drugs. CONCLUSION: For the studied drugs, implementation of dose banding should be considered as it entails no significant increase in interindividual plasma exposure
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