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71.
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   
72.
JC virus (JCV) is an ubiquitous human polyomavirus that frequently resides in the kidneys of healthy individuals and is excreted in the urine of a large proportion of the adult population. Polyomaviruses are associated with disease largely in immunocompromised individuals (progressive multifocal leukoencephalopathy). Colorectal cancers can show chromosome instability and it was hypothesized that JCV may account for some of this instability. We screened urine from 45 healthy donors and 233 colorectal cancer/normal tissue pairs for the presence of JCV sequences using a Taqman assay. This assay could detect 1 virus genome in 10 human genomes. In the urine samples, we found an infection rate of approximately 70%. The JCV isolates in these samples could be categorized into four JCV types (2B, 4, 7, and 8), none of which had a rearranged regulatory region. Among the colon tissues, one normal tissue (<0.5%) and none of the matched tumors tested positive for JCV. There is no evidence in these data to indicate that JCV is the cause of genetic instability in colorectal cancer.  相似文献   
73.
BACKGROUND: To assess antitumor activity and toxicity of pemetrexed in metastatic breast cancer (MBC) patients previously treated with anthracyclines. PATIENTS AND METHODS: Seventy-seven MBC patients from 12 European institutions were entered into the study. Seventy-two patients were considered evaluable for response and toxicity. Forty-two patients were classified as anthracycline-failure (relapse >30 days after completion of a prior anthracycline regimen) and 30 as anthracycline-refractory (progression within 30 days after anthracycline therapy). Pemetrexed 600 mg/m(2) was administered intravenously every 3 weeks until progressive disease or unacceptable toxicity. RESULTS: There were three complete and 12 partial responders [response rate 21% (95% confidence interval 12%)]. Response rates in the anthracycline-failure and anthracycline-refractory groups were 24% and 17%, respectively. A subset of 31 patients pretreated with anthracyclines and taxanes had a response rate of 26%. Median duration of response and median survival were 5.5 and 10.7 months, respectively (13 months in the failure group and 5.7 months for refractory). Grade 3/4 toxicities included neutropenia and thrombocytopenia in 56% and 19% of patients, respectively. Nine patients (12%) experienced neutropenic fever. Grade 3/4 non-hematological toxicities included skin rash (10%), nausea (12%), fatigue (10%) and stomatitis (5%). CONCLUSION: Our trial demonstrates pemetrexed to be active in breast cancer, with manageable toxicity. Activity of pemetrexed did not appear to be adversely affected by prior taxane, 5-fluorouracil or endocrine treatments.  相似文献   
74.
The aim of this study was to study pulmonary radiological abnormalities with chest radiography following different radiotherapy (RT) techniques for breast cancer with respect to regions and density, and their association with pulmonary complications and reduction in vital capacity (VC). Chest radiographs were performed 5 months following local or loco-regional RT in 167 breast cancer patients. The radiological abnormalities were analysed with a classification system originally proposed by Arriagada and evaluated according to increasing density (0–3) and affected lung regions (apical–lateral, basal–lateral, central–parahilar). The highest-density grades in each region were added together to form scores ranging from 0 to 9. The patients were monitored for RT-induced pulmonary complications. The VC was measured prior to and 5 months following RT. An independent evaluation of 51 patients was performed by a second radiologist to control the reproducibility of the classification system. Increasing scores were associated with loco-regional RT and pulmonary complications (P < 0.001). The mean reduction of VC for patients scoring 0–3 (–30 ml) vs 4–9 (–161 ml) was not statistically significant (P = 0.10). Scores of 4–9 were more frequently observed in older patients (P < 0.001). The independent evaluations by two radiologists revealed good agreement (P < 0.001) and no systematic inter-observer variation. Radiological abnormalities on chest radiographs, scored according to Arriagada, can be used as an objective end point for RT-induced pulmonary side effects in breast cancer. Received: 4 February 1999; Revision received: 1 April 1999; Accepted: 5 May 1999  相似文献   
75.
Extensive studies have been performed to evaluate different factors that may affect on spinal interbody fusion, but the role of intervertebral disc tissue in the fusion process remains unclear. To study the influence of intervertebral disc tissue on osteoblast metabolism, we harvested disc tissue from patients who had undergone spinal surgery. The nucleus pulposus and annulus fibrosus were separately co-cultured with osteoblast-like cells SaOS-2 by means of culture inserts or organ culture. We assayed alkaline phosphoatase activity, 3H-thymidine incorporation into the DNA, and production of collagen type I, IL-1beta, IL-6, IL-10, and TNF-alpha. Exposure of the nucleus pulposus (NP) to osteoblast-like cells revealed stimulation of alkaline phosphatase production, 3H-thymidine incorporation and collagen type I production. Exposure of the annulus fibrosus (AF) stimulated 3H-thymidine incorporation and collagen type I production, but did not affect ALP activity. IL-6 was detected after application of NP and AF. Interleukin IL-10, IL-1beta and TNF-alpha were all below detection levels after application of disc tissue. Our findings show that frozen disc tissue stimulates the metabolism of osteoblast-like cells in vitro.  相似文献   
76.
77.
Few epidemiologic studies have investigated the potential relation between flavonoids and breast cancer risk. We have applied recently published data on the composition of foods and beverages in terms of six principal classes of flavonoids (i.e., flavanones, flavan-3-ols, flavonols, flavones, anthocyanidines, and isoflavones) on dietary information collected in a large-case control study of breast cancer conducted in Italy between 1991 and 1994. The study included 2,569 women with incident, histologically confirmed breast cancer, and 2,588 hospital controls. Odds ratios (OR) and 95% confidence intervals were estimated by multiple logistic regression models. After allowance for major confounding factors and energy intake, a reduced risk of breast cancer was found for increasing intake of flavones (OR, 0.81, for the highest versus the lowest quintile; P-trend, 0.02), and flavonols (OR, 0.80; P-trend, 0.06). No significant association was found for other flavonoids, including flavanones (OR, 0.95), flavan-3-ols (OR, 0.86), anthocyanidins (OR, 1.09), as well as for isoflavones (OR, 1.05). The findings of this large study of an inverse association between flavones and breast cancer risk confirm the results of a Greek study.  相似文献   
78.
Poor absorption and stability of peptides are the major obstacles concerning the development of therapeutically relevant iontophoretic devices for the transdermal delivery of peptides. The present study examined the impact of constant and pulsed (direct/alternating) current profiles on the transport and stability of two decapeptides LHRH and Nafarelin. The stability of these peptides was studied in a physiological buffer solution, with electrical current, and when the peptide solution was exposed to the stratum corneum or to the epidermal/dermal side of human skin. Pulsed direct current profile was shown to be the most efficient in transporting both LHRH and Nafarelin across the human epidermis. Furthermore, the percentage of intact LHRH in the receiver phase was slightly higher when a pulsed current profile was used. Both the peptides were stable in a physiological buffer and under the influence of current, but LHRH was degraded especially in contact with the dermal side of the skin. Altogether five hydrolytic degradation products of LHRH were observed, and they were identified by LC-ESI/MS and LC-ESI/MS/MS. No degradation products of Nafarelin were observed. It is concluded that the pulsed direct current profile may provide at least a partial solution for the transdermal delivery of peptides in terms of improved transport efficacy and peptide stability.  相似文献   
79.
80.
The San Carlos Gestational Diabetes Mellitus (GDM) prevention study, a nutritional intervention RCT based on a Mediterranean Diet (MedDiet), has been shown to reduce the incidence of GDM. The objective of this study is to investigate the relationship of leptin, adiponectin, interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α), insulin and HOMA-IRand circulating miRNAs (miR-29a-3p, miR-103a-3p, miR-132-3p, miR-222-3p) with the appearance of GDM and with MedDiet-based nutritional intervention, at 24–28 gestational weeks (GW), and in glucose regulation 2–3 years post-delivery (PD). A total of 313 pregnant women, 77 with GDM vs. 236 with normal glucose tolerance (NGT), 141 from the control group (CG, MedDiet restricting the consumption of dietary fat including EVOO and nuts during pregnancy) vs. 172 from the intervention group (IG, MedDiet supplemented with extra virgin olive oil (EVOO) and pistachios during pregnancy) were compared at Visit 1 (8–12 GW), Visit 2 (24–28 GW) and Visit 3 (2–3 years PD). Expression of miRNAs was determined by the Exiqon miRCURY LNA RT-PCR system. Leptin, adiponectin, IL-6 and TNF-α, were measured by Milliplex® immunoassays on Luminex 200 and insulin by RIA. Women with GDM vs. NTG had significantly higher leptin median (Q1–Q3) levels (14.6 (9.2–19.4) vs. 9.6 (6.0–15.1) ng/mL; p < 0.05) and insulin levels (11.4 (8.6–16.5) vs. 9.4 (7.0–12.8) µUI/mL; p < 0.001) and lower adiponectin (12.9 (9.8–17.2) vs. 17.0 (13.3–22.4) µg/mL; p < 0.001) at Visit 2. These findings persisted in Visit 3, with overexpression of miR-222-3p (1.45 (0.76–2.21) vs. 0.99 (0.21–1.70); p < 0.05)) and higher levels of Il-6 and TNF-α. When the IG is compared with the CG lower levels of insulin, HOMA-IR-IR, IL-6 levels at Visit 2 and 3 and leptin levels only at Visit 2 were observed. An overexpression of miR-222-3p and miR-103a-3p were also observed in IG at Visit 2 and 3. The miR-222-3p and miR103a-3p expression correlated with insulin levels, HOMA-IR, IL-6 and TNF-α at Visit 2 (all p < 0.05). These data support the association of leptin, adiponectin and insulin/HOMA-IR with GDM, as well as the association of insulin/HOMA-IR and IL-6 and miR-222-3p and miR-103a-3p expression with a MedDiet-based nutritional intervention.  相似文献   
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