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1.
L-ascorbic acid is an essential dietary vitamin in humans, primates and certain mammals and is endogenously syn-thesised in some species. Epidemiological and ecological studies have shown that L-ascorbic acid has a protective effect against cancer, in particular non-hormone-dependent malignancies, such as oropharyngeal neoplasms. Experimental in vivo and in vitro studies, however, have yielded more controversial results, suggesting that the effects of L-ascorbic acid are dose- and perhaps, time-dependent with different effects depending on the species or organ studied. An update of the epidemiological and experimental evidence linking L-ascorbic acid to oral cancer and carcinogenesis is discussed together with a brief review of the possible mechanisms of action of L-ascorbic acid. 相似文献
2.
Total radical trapping antioxidant potential (TRAP) and exercise 总被引:1,自引:0,他引:1
Sharpe PC; Duly EB; MacAuley D; McCrum EE; Mulholland C; Stott G; Boreham CA; Kennedy G; Evans AE; Trinick TR 《QJM : monthly journal of the Association of Physicians》1996,89(3):223-228
The relationship between physical activity, physical fitness and total
radical trapping antioxidant potential (TRAP) was examined in the Northern
Ireland Health and Activity Survey. This was a cross-sectional population
study (n = 1600) using a two-stage probability sample of the population.
TRAP was calculated using the sum of the individual serum antioxidant
concentrations (urate, protein thiols, ascorbate, alpha tocopherol and
bilirubin) multiplied by their respective stoichiometric values. Physical
fitness was determined by estimation of VO2max by extrapolation from
submaximal oxygen uptake, and physical activity was recorded by
computer-assisted interview. Mean serum TRAP concentrations were
significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared
to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female
smokers had significantly lower TRAP values than non-smokers (males p <
0.0001, females p = 0.02). In females, there was a positive relationship of
TRAP with age (p < 0.001) and body mass index (p < 0.001) but a
negative relationship with physical fitness (p < 0.05). The known
beneficial effects of exercise and activity do not appear to be directly
mediated through increased antioxidant status.
相似文献
3.
4.
Anthony L Bui Rouselle F Lavado Elizabeth K Johnson Benjamin PC Brooks Michael K Freeman Casey M Graves Annie Haakenstad Benjamin Shoemaker Michael Hanlon Joseph L Dieleman 《Bulletin of the World Health Organization》2015,93(8):566-576D
Objective
To collect, compile and evaluate publicly available national health accounts (NHA) reports produced worldwide between 1996 and 2010.Methods
We downloaded country-generated NHA reports from the World Health Organization global health expenditure database and the Organisation for Economic Co-operation and Development (OECD) StatExtract website. We also obtained reports from Abt Associates, through contacts in individual countries and through an online search. We compiled data in the four main types used in these reports: (i) financing source; (ii) financing agent; (iii) health function; and (iv) health provider. We combined and adjusted data to conform with OECD’s first edition of A system of health accounts manual, (2000).Findings
We identified 872 NHA reports from 117 countries containing a total of 2936 matrices for the four data types. Most countries did not provide complete health expenditure data: only 252 of the 872 reports contained data in all four types. Thirty-eight countries reported an average not-specified-by-kind value greater than 20% for all data types and years. Some countries reported substantial year-on-year changes in both the level and composition of health expenditure that were probably produced by data-generation processes. All study data are publicly available at http://vizhub.healthdata.org/nha/.Conclusion
Data from NHA reports on health expenditure are often incomplete and, in some cases, of questionable quality. Better data would help finance ministries allocate resources to health systems, assist health ministries in allocating capital within the health sector and enable researchers to make accurate comparisons between health systems. 相似文献5.
6.
Sawaya H Sebag IA Plana JC Januzzi JL Ky B Cohen V Gosavi S Carver JR Wiegers SE Martin RP Picard MH Gerszten RE Halpern EF Passeri J Kuter I Scherrer-Crosbie M 《The American journal of cardiology》2011,107(9):1663-1380
As breast cancer survival increases, cardiotoxicity associated with chemotherapeutic regimens such as anthracyclines and trastuzumab becomes a more significant issue. Assessment of the left ventricular (LV) ejection fraction fails to detect subtle alterations in LV function. The objective of this study was to evaluate whether more sensitive echocardiographic measurements and biomarkers could predict future cardiac dysfunction in chemotherapy-treated patients. Forty-three patients diagnosed with breast cancer who received anthracyclines and trastuzumab therapy underwent echocardiography and blood sampling at 3 time points (baseline and 3 and 6 months during the course of chemotherapy). The LV ejection fraction; peak systolic myocardial longitudinal, radial, and circumferential strain; echocardiographic markers of diastolic function; N-terminal pro-B-type natriuretic peptide; and high-sensitivity cardiac troponin I were measured. Nine patients (21%) developed cardiotoxicity (1 at 3 months and 8 at 6 months) as defined by the Cardiac Review and Evaluation Committee reviewing trastuzumab. A decrease in longitudinal strain from baseline to 3 months and detectable high-sensitivity cardiac troponin I at 3 months were independent predictors of the development of cardiotoxicity at 6 months. The LV ejection fraction, parameters of diastolic function, and N-terminal pro-B-type natriuretic peptide did not predict cardiotoxicity. In conclusion, cardiac troponin plasma concentrations and longitudinal strain predict the development of cardiotoxicity in patients treated with anthracyclines and trastuzumab. The 2 parameters may be useful to detect chemotherapy-treated patients who may benefit from alternative therapies, potentially decreasing the incidence of cardiotoxicity and its associated morbidity and mortality. 相似文献
7.
Ingo Helbig Marielle E M Swinkels Emmelien Aten Almuth Caliebe Ruben van 't Slot Rainer Boor Sarah von Spiczak Hiltrud Muhle Johanna A J?hn Ellen van Binsbergen Onno van Nieuwenhuizen Floor E Jansen Kees P J Braun Gerrit-Jan de Haan Niels Tommerup Ulrich Stephani Helle Hjalgrim Martin Poot Dick Lindhout Eva H Brilstra Rikke S M?ller Bobby PC Koeleman 《European journal of human genetics : EJHG》2014,22(7):896-901
A genetic contribution to a broad range of epilepsies has been postulated, and particularly copy number variations (CNVs) have emerged as significant genetic risk factors. However, the role of CNVs in patients with epilepsies with complex phenotypes is not known. Therefore, we investigated the role of CNVs in patients with unclassified epilepsies and complex phenotypes. A total of 222 patients from three European countries, including patients with structural lesions on magnetic resonance imaging (MRI), dysmorphic features, and multiple congenital anomalies, were clinically evaluated and screened for CNVs. MRI findings including acquired or developmental lesions and patient characteristics were subdivided and analyzed in subgroups. MRI data were available for 88.3% of patients, of whom 41.6% had abnormal MRI findings. Eighty-eight rare CNVs were discovered in 71 out of 222 patients (31.9%). Segregation of all identified variants could be assessed in 42 patients, 11 of which were de novo. The frequency of all structural variants and de novo variants was not statistically different between patients with or without MRI abnormalities or MRI subcategories. Patients with dysmorphic features were more likely to carry a rare CNV. Genome-wide screening methods for rare CNVs may provide clues for the genetic etiology in patients with a broader range of epilepsies than previously anticipated, including in patients with various brain anomalies detectable by MRI. Performing genome-wide screens for rare CNVs can be a valuable contribution to the routine diagnostic workup in patients with a broad range of childhood epilepsies. 相似文献
8.
9.
A study was conducted on the phosphorylation of proteins in the neutrophil cytosol in response to phorbol myristate acetate (PMA) and N- formyl-methionyl-leucyl-phenylalanine (fMLP). Autoradiography of gel electrophoretograms prepared from neutrophils incubated with 32Pi in the presence and absence of the activators showed nine proteins whose state of phosphorylation was affected by neutrophil activation. 32P was gained by eight of these proteins and was lost by the ninth. For all but one of these proteins, the change in the extent of labeling appeared to reach completion by one to two minutes. It was possible to quantitate the changes in 32P content of three of the nine proteins. One of these was the 20-kD protein that lost label when the neutrophils were activated. Quantitation showed that over half the 32P present in this protein in the resting state was gone within 0.2 minutes after activation. The other two were proteins weighing 11 and 69 kD. The phosphorylation characteristics of these two proteins differed, depending on whether activation had been carried out with PMA or fMLP. These differences in protein phosphorylation support other evidence suggesting that PMA and fMLP do not activate neutrophils by identical biochemical pathways. Differences in phosphorylation between resting and activated cells were not affected by dibutyryl cyclic guanosine monophosphate (cGMP), dibutyryl cyclic adenosine monophosphate (cAMP), theophylline, aspirin, hydrocortisone, or colchicine. The differences were abolished, however, by 30 mumol/L trifluoperazine. This finding is consistent with the hypothesis that the calcium/calmodulin system plays a biochemical role in the activation of neutrophils. 相似文献
10.