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121.
Oral bioavailability of the antioxidant astaxanthin in humans is enhanced by incorporation of lipid based formulations. 总被引:1,自引:0,他引:1
Johanna Mercke Odeberg Ake Lignell Annette Pettersson Peter H?glund 《European journal of pharmaceutical sciences》2003,19(4):299-304
Astaxanthin is a carotenoid with antioxidant properties, synthesised by plants and algae, and distributed in marine seafood. Astaxanthin is also available as a food supplement, but, like other carotenoids, is a very lipophilic compound and has low oral bioavailability. However, bioavailability can be enhanced in the presence of fat. There is not much information in the literature about the pharmacokinetics of oral astaxanthin in humans. In this open parallel study, healthy male volunteers received a single dose of 40 mg astaxanthin, as lipid based formulations or as a commercially available food supplement, followed by blood sampling for further analysis of plasma concentrations. Pharmacokinetic parameters were calculated to evaluate the extent and rate of absorption from each formulation. The elimination half-life was 15.9+/-5.3 h (n=32), and showed a mono-phasic curve. Three lipid based formulations: long-chain triglyceride (palm oil) and polysorbate 80 (formulation A), glycerol mono- and dioleate and polysorbate 80 (formulation B), and glycerol mono- and dioleate, polysorbate 80 and sorbitan monooleate (formulation C), all showed enhanced bioavailability, ranging from 1.7 to 3.7 times that of the reference formulation. The highest bioavailability was observed with formulation B, containing a high content of the hydrophilic synthetic surfactant polysorbate 80. 相似文献
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David B Preen Belinda E S Bailey Alan Wright Peter Kendall Martin Phillips Joseph Hung Randall Hendriks Annette Mather Elizabeth Williams 《International journal for quality in health care》2005,17(1):43-51
OBJECTIVE: To determine the impact of a hospital-coordinated discharge care plan, involving a multidisciplinary team of primary health care providers, on hospital length of stay, quality of life, and both patient and general practitioner inclusion in, and satisfaction with, discharge procedures. DESIGN: This investigation comprised a prospective, randomized, controlled, clinical trial. SETTING: This multicentre and cross-jurisdictional study focused on areas of tertiary and primary health care as well as community allied health in Western Australia. PARTICIPANTS: Patients (n = 189) with chronic cardiorespiratory diagnoses were recruited from respiratory, cardiovascular, and general medical wards at two tertiary hospitals. INTERVENTION: Subjects were randomly assigned to one of two groups. Intervention group patients received a discharge care plan in accordance with that outlined in the Australian Enhanced Primary Care Package, completed before discharge and sent to the patient's general practitioner and other community service providers for review. Control patients were discharged under existing hospital processes. Outcome measures. Patients and general practitioners were surveyed pre-discharge and 7 days post-discharge for quality of life and opinion of discharge procedures. Hospital length of stay was also determined. RESULTS: Significant improvements in discharge planning involvement, health service access, confidence with discharge procedures, and opinion of discharge based on previous experience were seen for patients who received the discharge care plan. Further, improved perceptions of mental quality of life were observed within the first week post-discharge for intervention patients. Length of stay showed no difference between groups. Extent and speed of hospital-general practitioner communication were significantly improved via the intervention. CONCLUSIONS: Our results indicate that a multidisciplinary discharge care plan, initiated before separation, improves quality of life, involvement, and satisfaction with discharge care, and hospital-general practitioner integration. As such, it possesses benefits over current Western Australian hospital discharge procedures for the care of chronically ill populations. 相似文献
125.
This study is a review of literature on the factors affecting the retention and turnover of hospital consultants and midwives. While there is widespread concern and acknowledgement of staff retention problems for professional occupations within the NHS, far less research has analysed the causes of the staff retention problems for the occupations in question. This study shows that there is a dearth of literature in this area and that systematic comparative analysis of retention and turnover factors through both primary and secondary research is urgently required in order that policy-making can take place on the basis of informed choice. Tentative initial findings were that lack of appreciation or perceptions of not being valued are key factors influencing turnover for both occupations. Working hours, workload and work schedules are also common concerns to both groups. In addition, career development, promotion and appreciation of contribution were important retention factors for midwives, while a supportive professional environment, reduction in workload and working hours and more flexible work patterns were important to consultants. 相似文献
126.
Analysis of the S810L point mutation of the mineralocorticoid receptor in patients with pregnancy-induced hypertension. 总被引:1,自引:0,他引:1
Annette Schmider-Ross M Wirsing U Büscher H Neitzel M Krause W Henrich A Reles J W Dudenhausen 《Hypertension in pregnancy》2004,23(1):113-119
OBJECTIVE: A missense mutation at codon 810 (Ser --> Leu) of the mineralocorticoid receptor was recently observed in a family with early manifestation of hypertension. Our objective was to determine if this mineralocorticoid receptor alterations is prevalent in patients with pregnancy-induced hypertension. METHODS: Thirty-eight women with hypertension during pregnancy were tested for the mineralocorticoid receptor gene mutation. DNA was extracted out of blood leucocytes. PCR and automated DNA sequencing were used to analyze exon 6 for the S810L missense mutation. Anamnestical data concerning cardiovascular risk factors and family history were evaluated with a questionnaire. Pregnancy course and outcome were documented in all cases. RESULTS: In 33 patients with pregnancy-induced hypertension and in five patients with exacerbation of preexisting hypertension in pregnancy no point mutations were found at codon 810 in exon 6. CONCLUSIONS: Our data suggest that the S810L missense mutation of the mineralocorticoid receptor does not play a major role in the etiology of pregnancy-induced hypertension in a German /Turkish population. 相似文献
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P53 mutation analysis of colorectal liver metastases: relation to actual survival, angiogenic status, and p53 overexpression. 总被引:4,自引:0,他引:4
Koert P de Jong Annette S H Gouw Paul M J G Peeters Marian Bulthuis Lorian Menkema Robert J Porte Maarten J H Slooff Harry van Goor Anke van den Berg 《Clinical cancer research》2005,11(11):4067-4073
PURPOSE: To correlate TP53 mutations with angiogenic status of the tumor and prognosis after liver surgery in patients with colorectal liver metastases and to correlate immunohistochemical staining of p53 protein with TP53 gene mutations. EXPERIMENTAL DESIGN: Tumors of 44 patients with surgically treated colorectal liver metastases were analyzed for (a) TP53 mutations using denaturing gradient gel electrophoresis followed by sequencing, (b) microvessel density using the hot spot overlap technique, (c) apoptotic rate in tumor cells and endothelial cells of tumor microvessels using double immunostaining for anti-cleaved caspase 3 and anti-CD34, and (d) expression of p53 protein using immunohistochemistry. RESULTS: TP53 mutations were detected in 36% of the metastases and occurred more frequently in liver metastases from left-sided colon tumors than from right-sided colon tumors (P = 0.04). In metastases with TP53 mutations, microvessel density was higher compared with tumors with wild-type p53. Endothelial cell apoptosis was not different in tumor microvessels from TP53-mutated versus nonmutated tumors. The 5-year actual survival was not influenced by TP53 mutational status, microvessel density, or endothelial cell apoptotic rate of the tumors. Based on immunohistochemical p53 overexpression, the positive and negative predictive values of TP53 mutations were 61% and 82%. CONCLUSIONS: In patients with surgically treated colorectal liver metastases, TP53 mutations and angiogenic status did not influence prognosis. Immunohistochemistry is not a reliable technique for detecting TP53 mutations. 相似文献
130.
Annette Paschen Mingxia Song Wolfram Osen Xuan Duc Nguyen Jan Mueller-Berghaus Daniela Fink Nadine Daniel Mariel Donzeau Wolfgang Nagel Harald Kropshofer Dirk Schadendorf 《Clinical cancer research》2005,11(14):5241-5247
PURPOSE: The frequently expressed differentiation antigen tyrosinase-related protein-2 (TRP-2) has repeatedly been described as a target of spontaneous cytotoxic T-cell responses in melanoma patients, suggesting that it might be an ideal candidate antigen for T cell-based immunotherapy. As a prerequisite for immunization, T-cell epitopes have to be identified. Whereas a number of HLA class I-presented TRP-2-derived epitopes are known, information about HLA class II-presented antigenic ligands recognized by CD4+ T helper (Th) cells is limited. EXPERIMENTAL DESIGN: The search for TRP-2-derived Th epitopes was carried out by competitive in vitro peptide binding studies with predicted HLA-DRB1*0301 ligands in combination with peptide and protein immunizations of HLA-DRB1*0301 transgenic mice. In vivo selected candidate epitopes were subsequently verified for their immunogenicity in human T-cell cultures. RESULTS: This strategy led to the characterization of TRP-2(60-74) as an HLA-DRB1*0301-restricted Th epitope. Importantly, TRP-2(60-74)-reactive human CD4+ Th cell lines, specifically recognizing target cells loaded with recombinant TRP-2 protein, could be established by repeated peptide stimulation of peripheral blood lymphocytes from several HLA-DRB1*03+ melanoma patients. Even short-term peptide stimulation of patients' peripheral blood lymphocytes showed the presence of TRP-2(60-74)-reactive T cells, suggesting that these T cells were already activated in vivo. CONCLUSION: Peptide TRP-2(60-74) might be a useful tool for the improvement of immunotherapy and immune monitoring of melanoma patients. 相似文献