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C Mix

Publications and source records attributed to C Mix.

12 recordsLinked to original sources

Regional gene flow and population structure of the wind-dispersed plant species Hypochaeris radicata (Asteraceae) in an agricultural landscape.

Using microsatellites, we investigated population structure and gene flow of the short-lived, wind-dispersed plant species Hypochaeris radicata in a fragmented agricultural landscape where more than 99% of the nutrient-poor grasslands have disappeared over the last century. We sampled populations in the few remaining high density populations in conservation areas, as well as individuals that occurred, with lower densities, in linear landscape elements, at two spatial scales. In a re-inventory of the landscape, after 3 years, both extinctions and colonizations of populations were observed. Contrary to expectations, no differences in genetic diversity between high and low density populations were observed. Both types of populations had relatively high levels of diversity. Overall genetic differentiation (theta) was 0.04 and significantly different from zero (P < 0.01). A significant isolation-by-distance pattern was found when all populations were simultaneously analysed (r = 0.24, P = 0.013). Isolation by distance was (marginally) significant at the small scale (r = 0.32, P = 0.06), whereas nonsignificant at the large spatial scale (r = -0.05, P = 0.66). A maximization-of-explained-variance procedure resulted in a threshold distance of 3.5 km above which populations were effectively genetically isolated. An additional partial exclusion Bayesian-based assignment test showed that overall 32.3% of the individuals were assigned to their population of origin, 48% were assigned to another population in the area and 19.7% were not assigned. Together, these results suggest high levels of gene flow. Seed dispersal contributes to the observed gene flow up to several hundred metres, which is higher than previously modelled using aerodynamic models on seed dispersal of H. radicata. We discuss the consequences of these results for an evaluation of the probability of persistence of this species in the fragmented landscape.

Asteraceae↗

Dose dependency of fluvastatin pharmacokinetics in serum determined by reversed phase HPLC.

BACKGROUND: Fluvastatin is an inhibitor of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, effectively lowering serum cholesterol concentrations. A high-performance liquid chromatography (HPLC) assay was developed that determined the pharmacokinetics of fluvastatin in healthy individuals after administration of 40 and 80 mg fluvastatin. METHODS: The method was linear for serum concentrations between 10 ng/mL and 5,000 ng/mL, showing good coefficients of variations and sample stability. After administration of 40 mg fluvastatin, the mean values of the area under the serum concentration vs time curve (AUC), the maximum serum drug concentration (C(max)), the time to reach C(max) (t(max)), and the serum elimination half-life time were 528.5 +/-358.8 ng/mL x h, 149.6 +/-56.0 ng/mL, 60.0 +/-30.0 minutes, and 108.0 +/-67.9 minutes, respectively. The corresponding values for a dose of 80 mg fluvastatin were 1417.7 +/-879.2 ng/mL x h, 1024.7 +/-1085.1 ng/mL, 60.0 +/-21.2 minutes, and 106.0 +/-73.6 minutes, respectively. Doubling of the dose from 40 mg to 80 mg caused an overproportional increase of AUC and C(max). RESULTS AND CONCLUSION: Results suggest that the measurement of fluvastatin serum concentrations by means of HPLC provides reliable data within the broad range of physiological serum concentrations. The pharmacokinetic data after administration of high doses (80 mg) showed an overproportional increase of AUC and C(max), suggesting a saturation of the hepatic first-pass effect. Thus, in patients treated with additional substances interfering with fluvastatin metabolism, fluvastatin serum concentrations should be analyzed.

Administration, Oral↗

Pharmacokinetics and pharmacodynamics of fluvastatin in heart transplant recipients taking cyclosporine A.

During the last decades, transplantation has become an established tool for the treatment of terminal organ failure. Beside immunological factors, hyperlipidemia is the main problem after heart transplantation, causing rapid transplant coronary artery disease (TxCAD) and poor long-term prognosis at the beginning of the transplantation. Heart transplant recipients are now effectively treated with lipid lowering substances, of which HMG-CoA-reductase inhibitors are the most potent. However, treatment with these substances correlates with an increased risk for the development of rhabdomyolysis due to therapy with the immunosuppressive cyclosporine A. Our study monitored the safety and efficacy of treatment with the HMG-CoA reductase inhibitor fluvastatin in heart transplant recipients compared to healthy controls. We investigated 10 patients receiving immunosuppressive therapy consisting of cyclosporine A, prednisone, and azathioprine who had increased concentrations of LDL-cholesterol (LDL-C), and 10 age-matched healthy controls. The patients were treated with 40 mg/day fluvastatin for 4 weeks and 20 mg/day for 4 additional weeks. Control individuals received 40 mg/day fluvastatin for 4 weeks only. Parameters of fluvastatin pharmacokinetics (maximum concentration of the drug (C(max.)), time (t(max.)) to reach C(max.), area under the concentration vs. time curve (AUC(0h-24h)), elimination half-life time (t(1/2))), apparent total body clearance (CL), blood cyclosporine A concentration, plasma lipids, and safety parameters were determined in both study groups at the beginning of the study and after 4 weeks. The latter were determined in the patient group also after 8 and 12 weeks. Treatment with 40 mg/day fluvastatin caused a significant decrease in total cholesterol (patients: 5.47 +/- 1.32 mmol/L vs. 7.30 +/- 1.83 mmol/L; controls: 4.69 +/- 0.64 mmol/L vs. 5.81 +/- 0.72 mmol/L), LDL-C (patients: 3.28 +/- 1.25 mmol/L vs. 5.00 +/- 1.85 mmol/L; controls: 2.58 +/- 0.63 mmol/L vs. 3.50 +/- 0.70 mmol/L), and triglycerides (patients: 1.99 +/- 0.77 mmol/L vs. 2.50 +/- 1.00 mmol/L; controls: 1.24 +/- 0.46 mmol/L vs. 1.72 +/- 0.67 mmol/L) in both study groups, whereas HDL-C was not significantly changed (patients: 1.29 +/- 0.35 mmol/L vs. 1.17 +/- 0.32 mmol/L; controls: 1.55 +/- 0.30 mmol/L vs. 1.53 +/- 0.26 mmol/L). Values of C(max.) and AUC(0h-24h) were higher in the patient group than in the control group (day 1, patients vs. controls, C(max.): 869.4 +/- 604.0 ng/mL vs. 211.9 +/- 113.9 ng/mL; AUC(0h-24h): 1948.8 +/- 1347.9 ng/mL*h vs. 549.4 +/- 247.4 ng/mL*h), whereas the corresponding value of CL was lower in the patient group (33.3 +/- 24.5 L/h vs. 107.9 +/- 95.8 L/h), and the values of t(max.) and t(1/2) showed no differences. In addition, values of C(max.) and AUC(0h-24h) after administration of 40 mg/day fluvastatin for 4 weeks in both groups were slightly higher than at the beginning, whereas the value of CL was slightly lower (day 28, patients vs. controls, C(max.): 1530.4 +/- 960.4 ng/mL vs. 254.7 +/- 199.8 ng/mL; AUC(0h-24h): 2615.3 +/- 1379.4 ng/mL*h vs. 841.8 +/- 421.4 ng/mL*h; CL: day 28, 21.4 +/- 15.3 L/h vs. 61.5 +/- 36.6 L/h). Except for an intermittent increase of creatine kinase, safety parameters showed no increases within the observation period. Our data suggest that fluvastatin effectively lowers plasma concentrations of cholesterol and LDL-C in patients after heart transplantation, however, the metabolism of fluvastatin is affected by concomitant therapy with cyclosporine A. Serum concentrations of fluvastatin should be monitored in cases of concomitant therapy with other substances interfering in the metabolism by competing cytochrome enzymes.

Adult↗

Influence of psychosocial resources on the relationship between lifestyle and cardiovascular or mental health.

Among middle-aged women: The factor beta-lipoproteins is significantly influenced by cigarette smoking and by the intensity of physical activity at leisure time. The factor alpha-lipoproteins is not influenced by these lifestyle factors. The leukocyte count is higher among smokers. It is not significantly associated with other inflammation markers. The pre-diabetic risk profile is improved by physical activity at leisure time and by rigid eating behaviour in stressful situations. The physical activity at leisure time and a rigid eating behaviour in stressful situations play a positive role for mental health, too. Styles of coping with stress, action styles or sense of coherence do not influence the relationships between lifestyle factors and cardiovascular risk factors. Psychosocial resources intensify the relationships between lifestyle and mental health.

Adaptation, Psychological↗

Lipids and stability of menopausal status in middle-aged women within two years.

In the whole population total cholesterol (TC) was unchanged within two years. The triglyceride (TG) level increased significantly, but HDLC increased too between 1996 and 1998. The increase of TG concentration was significantly in the stable group only, whereas the increase of HDLC concentration was observed in both groups. "Depressed mood" and "anxiety" seem to have a positive influence on the TC levels.

Female↗

Even moderate cigarette smoking influences the pattern of circulating monocytes and the concentration of sICAM-1.

The pattern of circulating monocyte subtypes and the concentration of the soluble intercellular adhesion molecule-1 (ICAM-1) were compared in middle-aged female moderate smokers and lifetime non-smokers. Total leukocyte and monocyte counts were higher in smokers. The pattern of circulating monocytes of smokers was changed toward lower absolute counts of activated (CD16+/CD64+) monocytes and (CD16+/CD14+) monocyte-macrophages and higher counts of nonactivated monocytes. The serum concentration of soluble ICAM-1 was significantly higher in smokers than in non-smokers. It is supposed that even moderate cigarette smoking leads to an activation of the circulating monocytes and their increased adhesion to the endothelium.

Antigens, CD↗

Food supply abundant increase of serum selenium concentrations in middle-aged Dresden women between 1990 and 1996. DRECAN-Team. Dresden Cardiovascular Risk and Nutrition.

Serum selenium concentration was measured in middle-aged Dresden (East Germany) women in 1990 and 1996. In 1990, the serum concentration of selenium in middle-aged women was higher than in men living under the same environmental conditions (0.98 +/- 0.32 vs 0.82 +/- 0.19 micromol/l). In 1996, the serum concentration of selenium in middle-aged women was significantly higher than in 1990 (1.19 +/- 0.34 micromol/l). This increase seems to be caused by the changed foodstuff supply after the reunification of Germany. Selenium values did not correlate with age, blood pressure or daily energy intake. Moderate smoking and menopausal status did not influence the selenium levels. In 1990, the serum concentration of selenium was the highest in those women who consumed the lowest amounts of carbohydrates or fibers, or who had the highest consumption of meat, fresh fish or potatoes.

Adult↗

[Functional results following complicated injuries of the extremities--how can they be improved?].

This study evaluates the critical points in the management of 48 patients with injured arteries of the lower limb between 1980 and 1986. 77% of the traumas were resultant from blunt vehicular traffic mishaps. 13 patients were treated within 6 h, 8 patients later than 6 h, 21 patients later than 24 h post injury. Delays in diagnosis occurred due to lack of or no indication for vascular trauma. Careful physical examination and aggressive use of angiography is essential in improving limb salvage rates, while doppler investigation may lead to improper diagnosis. Overall limb salvage was 69%, however, no reconstruction was possible in 6 cases (13%). 38 of the 42 arterial reconstructions required interposition of venous bypass grafts, four end to end anastomoses. Eleven patients had associated venous injuries, which in nine cases were repaired. Venous ligation in three cases was attributed with increased complication. In three cases ischemia time was shortened by the use of temporary javid shunts for rapid restoration of arterial flow. 50% of the patients were found to require fasciotomy, either pre- or postvascular repair. Early fasciotomy, however was found to be most beneficial. Fractures were treated in 15 cases with the external fixator, in 21 cases with internal fixation. Delayed revascularization after 24 h combined with aggressive debriding of muscle necrosis and the employment of vascularized muscular and skin flaps resulted in a decline in amputation rates and improved functional results.

Adult↗

Extended femoro-distal bypasses for limb salvage: are they worthwhile?

UNLABELLED: In this report on 93 patients with limb-threatening leg ischemia the surgical procedures applied were malleolar bypasses (14), sequential bypasses (12) and femoro-distal bypasses with adjunct AV fistulas (67). The first two methods resulted in favourable limb-salvage and patency rates. However the results of such reconstructions essentially depend on the quality of primary and secondary foot arcades. In peripheral calf and foot arterial occlusions we have applied a distal arteriovenous fistula as an adjunct measure to maintain bypass patency in the crural region. 67 patients were operated on according to this method: 30 females and 37 males with an average age of 70.3 years. 29% had rest-pain and 71% had gangrene. The majority had already been operated on at least once. 7 patients had been amputated contralaterally. RESULTS: 79% of the patients had a patent graft after one month. The incidence of limb salvage was 77%. At two years 47% of all grafts are still patent and the incidence of limb-salvage is 52%. However, this operation should be exclusively designed for limb-salvage and for cases with extremely poor run-off.

Arteries↗