Biomedical subjects

K Ostrowski

Publications and source records attributed to K Ostrowski.

At least 37 records · Page 2Linked to original sources

PubMed2000

Physical activity and plasma interleukin-6 in humans--effect of intensity of exercise.

The present study included data from three marathon races to investigate the hypothesis that a relationship exists between running intensity and elevated concentrations of interleukin (IL)-6 in plasma. The study included a total of 53 subjects whose mean age was 30.6 [95% confidence interval (CI) 1.4] years, mean body mass 77.7 (95% CI 2.0) kg, mean maximal oxygen uptake (VO2max) 59.3 (95% CI 1.4) ml x min(-1) x kg(-1), and who had participated in the Copenhagen Marathons of 1996, 1997 or 1998, achieving a mean running time of 206 (95% CI 7) min. Running intensity was calculated as running speed divided by VO2 max. The concentration of IL-6 in plasma peaked immediately after the run. There was a negative correlation between peak IL-6 concentration and running time (r = -0.30, P<0.05) and a positive correlation between peak IL-6 concentration and running intensity (r = 0.32, P<0.05). The IL-1 receptor antagonist (IL-1ra) plasma concentration peaked 1.5 h after the run and there was a positive correlation between the peak plasma concentrations of IL-6 and IL-1ra (r = 0.39, P<0.01). Creatine kinase (CK) plasma concentration peaked on the 1st day after the run, but no association was found between peak concentrations of IL-6 and CK. In conclusion, the results confirmed the hypothesized association between plasma IL-6 concentration and running intensity, but did not confirm the previous finding of a connection between IL-6 plasma concentration and muscle damage.

Adult↗

PubMed2000

Cytokines in aging and exercise.

Aging is associated with increased inflammatory activity. Increased plasma levels of tumour necrosis factor (TNF)-alpha were found in centenarians aged 100 years and in individuals aged 80-81 years when compared to a young control group. Plasma levels of TNF-alpha were linearly correlated to plasma levels of interleukin (IL)-6, TNF-receptors and C-reactive protein. High levels of TNF-alpha were directly related to dementia and to a low blood pressure ankle-arm index, indicating generalized atherosclerosis. In hospitalized patients with Streptococcus pneumonia infection, aging was associated with prolonged inflammatory activity. Similar results were found using an in vivo endotoxin challenge model in old versus young humans. Strenuous exercise induces increased levels in a number of proinflammatory and anti-inflammatory cytokines, naturally occurring cytokine inhibitors and chemokines. Thus, increased plasma levels of TNF-alpha, IL-1, IL-6, IL-1 receptor antagonist (IL-Ira), TNF-receptors (TNF-R), IL-10, IL-8 and macrophage inflammatory protein (MIP)-1 are found after strenuous exercise. The cytokine response to strenuous exercise has similarities to the cytokine response to trauma and sepsis. Therefore, in future studies, exercise is suggested as an ethically applicable model to use in studies on mechanisms underlying the age-associated altered cytokine response.

Adult↗

PubMed2000

N-3 polyunsaturated fatty acids do not affect cytokine response to strenuous exercise.

The aim of the present study was to investigate whether fish oil supplementation was able to modulate the acute-phase response to strenuous exercise. Twenty male runners were randomized to receive supplementation (n = 10) with 6.0 g fish oil daily, containing 3.6 g n-3 polyunsaturated fatty acids (PUFA), for 6 wk or to receive no supplementation (n = 10) before participating in The Copenhagen Marathon 1998. Blood samples were collected before the race, immediately after, and 1.5 and 3 h postexercise. The fatty acid composition in blood mononuclear cells (BMNC) differed between the fish oil-supplemented and the control group, showing incorporation of n-3 PUFA and less arachidonic acid in BMNC in the supplemented group. The plasma levels of tumor necrosis factor-alpha, interleukin-6, and transforming growth factor-beta(1) peaked immediately after the run, the increase being 3-, 92-, and 1.1-fold, respectively, compared with resting samples. The level of interleukin-1 receptor antagonist peaked 1.5 h after exercise, with the increase being 87-fold. However, the cytokine levels did not differ among the two groups. Furthermore, supplementation with fish oil did not influence exercise-induced increases in leucocytes and creatine kinase. In conclusion, 6 wk of fish oil supplementation had no influence on the acute-phase response to strenuous exercise.

Adult↗

PubMed2000

[Secondary anticoagulant prophylaxis with low molecular heparins or oral anticoagulants and bone mineral density].

A broad spectrum of indications for low molecular weight heparin (LMWH) requires an assessment of side effects especially during prolonged administration. There are common risk factors for venous thromboembolism (VTE) and osteoporosis; heparin is "the drug of choice" for VTE treatment. The aim of our study was to assess the effect of treatment and prophylaxis with LMWH (enoxaparine sodium) and oral anticoagulant (acenocoumarol) for bone structure. Material consists of in- and outpatients. 49 densitometries were performed in 31 patients (in 15 cases double examination). We observed a decrease of bone mineral density in comparison to the initial examination in most cases: mean change of bone mass for examined areas was 3.05%.

Acenocoumarol↗

PubMed1999

Pro- and anti-inflammatory cytokine balance in strenuous exercise in humans.

1. The present study investigates to what extent and by which time course prolonged strenuous exercise influences the plasma concentration of pro-inflammatory and inflammation responsive cytokines as well as cytokine inhibitors and anti-inflammatory cytokines. 2. Ten male subjects (median age 27.5 years, range 24-37) completed the Copenhagen Marathon 1997 (median running time 3 : 26 (h : min), range 2 : 40-4 : 20). Blood samples were obtained before, immediately after and then every 30 min in a 4 h post-exercise recovery period. 3. The plasma concentrations of tumour necrosis factor (TNF)alpha, interleukin (IL)-1beta, IL-6, IL-1ra, sTNF-r1, sTNF-r2 and IL-10 were measured by enzyme-linked immunosorbent assay (ELISA). The highest concentration of IL-6 was found immediately after the race, whereas IL-1ra peaked 1 h post exercise (128-fold and 39-fold increase, respectively, as compared with the pre-exercise values). The plasma level of IL-1beta, TNFalpha, sTNF-r1 and sTNF-r2 peaked in the first hour after the exercise (2. 1-, 2.3-, 2.7- and 1.6-fold, respectively). The plasma level of IL-10 showed a 27-fold increase immediately post exercise. 4. In conclusion, strenuous exercise induces an increase in the pro-inflammatory cytokines TNFalpha and IL-1beta and a dramatic increase in the inflammation responsive cytokine IL-6. This is balanced by the release of cytokine inhibitors (IL-1ra, sTNF-r1 and sTNF-r2) and the anti-inflammatory cytokine IL-10. The study suggests that cytokine inhibitors and anti-inflammatory cytokines restrict the magnitude and duration of the inflammatory response to exercise.

Adult↗

PubMed1999

Persistence of bone collagen cross-links in skeletons of the Nuraghi population living in Sardinia 1500-1200 B.C.

Bone collagen has a specific molecular ultrastructure which can be proved by birefringence. This protein, forming the main organic component of bone tissue, is known to survive millennia in paleontological bones and teeth. Birefringence of bone collagen obtained from the skeletons of the Nuraghi population living in Sardinia c-ca 1500 years B.C. was found previously by the use of polarizing microscopy [1]. In this paper, using high pressure liquid chromatography (HPLC) techniques, we show the existence of bone collagen cross-links preserved in Nuraghi skeletons after more than 3000 years.

Amino Acids↗

PubMed1999

Quantitative ultrasound of phalanges and dual-energy X-ray absorptiometry of forearm and hand in patients with end-stage renal failure treated with dialysis.

The aim of the study was to evaluate the usefulness of quantitative ultrasound (QUS) measurement of the proximal phalanges of the hand in patients with end-stage renal failure (ESRF) treated with dialysis, and to compare results of this method with those from dual-energy X-ray absorptiometry (DXA) of hands and forearms (shaft and ultradistal site). Forty-one men aged 48.1 +/- 11.7 years and 31 women aged 43.1 +/- 12.3 years were examined. Mean QUS values of the hands in men and women with ESRF were significantly lower than the values of the healthy control group. There was a significant positive correlation between QUS and DXA of fingers, hands and also forearms, more pronounced in the shaft than in the ultradistal site. There was no significant difference in the measurements of extremities with or without a fistula. We conclude that QUS measurements are decreased in patients with ESRF treated with dialysis, and they correlate with DXA results. The simplicity of QUS makes it a valuable method in everyday practice. The clinical significance of the QUS results in these patients with ESRF treated with dialysis needs further investigation.

Absorptiometry, Photon↗

PubMed1999

Exercise and the immune system--influence of nutrition and ageing.

In essence, the immune system is enhanced during moderate and severe exercise, and only intense long-duration exercise is followed by impairment of the immune system. The latter includes suppressed concentration of lymphocytes, suppressed natural killer cell activity, lymphocyte proliferation and secretory IgA in saliva. During the time of immune impairment, referred to as "the open window", microbial agents, especially viruses may invade the host and infections may be established. One reason for the "overtraining effect" seen in elite athletes could be that this window of opportunism for pathogens is longer and the degree of immunosuppression more pronounced. Alterations in metabolism and metabolic factors may contribute to exercise-associated changes in immune function. Reductions in plasma-glutamine concentrations, altered plasma-glucose level, free oxygen radicals and prostaglandins (PG) released by the elevated number of neutrophils and monocytes may influence the function of lymphocytes and contribute to the impaired function of the later cells. Thus, nutritional supplementation with glutamine, carbohydrate, anti-oxidants or PG-inhibitors may, in principle, influence exercise-associated immune function. Although several intervention studies have been performed, it is premature to make recommendations regarding nutritional supplementation to avoid post-exercise impairment of the immune system.

Aging↗

PubMed1999

Exercise and immune function: effect of ageing and nutrition.

Strenuous exercise is followed by lymphopenia, neutrophilia, impaired natural immunity, decreased lymphocyte proliferative responses to mitogens, a low level of secretory immunoglobulin A in saliva, but high circulating levels of pro- and anti-inflammatory cytokines. These exercise-induced immune changes may provide the physiological basis of altered resistance to infections. The mechanisms underlying exercise-induced immune changes are multifactorial and include neuroendocrinological and metabolic mechanisms. Nutritional supplementation with glutamine abolishes the exercise-induced decline in plasma glutamine, but does not influence post-exercise immune impairment. However, carbohydrate loading diminishes most exercise effects of cytokines, lymphocyte and neutrophils. The diminished neutrophilia and elastase (EC 3.4.21.37) responses to eccentric exercise in elderly subjects were enhanced to levels comparable with those of young subjects by fish oil or vitamin E supplements. However, although vitamin C supplementation may diminish the risk of contracting an infection after strenuous exercise, it is not obvious that this effect is linked to an effect of vitamin C on exercise-induced immune changes. In conclusion, it is premature to make recommendations regarding nutritional supplementation to avoid post-exercise impairment of the immune system.

Aging↗

PubMed1999

[The prevention of bone mineral loss with hormonal replacement therapy in premenopausal women on dialysis with estrogen deficiency].

In 25-30% of premenopausal dialysis women low serum estrogen concentrations are observed. This "premature menopause" can significantly contribute to accelerated bone loss. The aim of the study was to evaluate the effect of estrogen-gestagen replacement therapy on bone mineral density (BMD) in hemodialysis women with secondary to uremia estrogen deficiency. Among 20 hemodialysis women, aged 18-45 years, with serum 17 beta-estradiol < 30 pg/ml, ten (group I) received transdermal estradiol with cyclic addition of noretisterone acetate (Estracomb TTS 50/0.25), and another ten formed the control group (group II). BMD was evaluated by dual photon x-ray absorptiometry (DEXA, Lunar) in: lumbar spine (L2-L4), 1/3 distal radius and femoral neck, before and after the study. Serum 17 beta-estradiol concentrations were measured before, and after 1, 3, 6 and 12 months of the study. After one year, in group I, in which serum 17 beta-estradiol normalized already during the first month (p < 0.001), an increase of in BMD was noted, although significant only in L2-L4 (p < 0.05). In group II, no change in serum 17 beta-estradiol and mild but insignificant decrease in BMD were observed. However, a comparison of BMD values after 12 months in both groups revealed the marked differences in all studied sites (p < 0.01, p < 0.02, p < 0.05 in L4-L2, distal radius and femoral neck, respectively). The mean serum calcium, phosphate, PTH and alkaline phosphatase activity were similar in both groups and did not change during the study. In premenopausal hemodialysis women with estrogen deficiency, hormonal replacement therapy inhibits bone demineralization and can be useful in prevention of early osteoporosis.

Adolescent↗

PubMed1999

[Hormonal replacement therapy and lipid metabolism in women on hemodialysis with secondary to uremia estrogen deficiency].

UNLABELLED: It has been reported that postmenopausal women taking hormonal replacement therapy (HRT) are at reduced risk for cardiovascular disease mainly because of favorable changes in serum LDL- and HDL-cholesterol. However, the therapy is also known to increase hepatic triglyceride production. Cardiovascular events are the leading cause of death in patients on dialysis and lipid abnormalities are common. The aim of the study was to evaluate the influence of HRT on lipid metabolism in premenopausal women undergoing hemodialysis with premature oestrogen withdrawal. 25 hemodialyzed women, aged 37 +/- 9 years (19-44 years) with serum 17 beta-estradiol < 30 pg/ml were divided into: group I (n = 13) treated with transdermal HRT (estradiol with cyclic norethisterone acetate--Estracomb TTS 50/0.25; Novartis), and control group II (n = 12). Before the treatment serum LDL-cholesterol concentrations were increased in 24% and serum triglycerides in 40% of patients, whereas HDL-cholesterol was decreased in 72% of patients. During one year, in group I a noticeable, 15% increase in serum HDL-cholesterol was observed from 0.90 +/- 0.23 to 1.04 +/- 0.19 mmol/l (34.8 +/- 8.8 to 39.8 +/- 7.4 mg/100 ml; p < 0.01). It was parallel to the increase in serum 17 beta-estradiol concentrations (from 20.5 +/- 8.91 to 50.3 +/- 17.20 pg/ml; p < 0.01). Serum LDL-cholesterol and triglycerides did not change significantly. In the control group all those values remained unchanged. CONCLUSIONS: In hemodialysis women with premature estrogen deficiency the transdermal cyclic HRT leads to the clinically important increase in serum HDL-cholesterol without significant changes in serum triglyceride concentrations and could be beneficial in reducing cardiovascular risk in this population.

Adult↗

PubMed1998

A trauma-like elevation of plasma cytokines in humans in response to treadmill running.

1. Elevated levels of cytokines, especially interleukin (IL)-6 and IL-1ra, can be measured in the plasma of athletes after exhaustive long term exercise. 2. The present study investigates the kinetics of several cytokines and chemokines in ten male athletes before, during and after 2.5 h of treadmill running at 75 % of maximal oxygen consumption (VO2,max). Blood was sampled before, every half-hour during running and every hour in the following 6 h recovery period. 3. The plasma concentration of IL-6 increased after 30 min of running, and peaked at the end of running with a 25-fold increase compared with the pre-exercise value. IL-1ra increased only after running, and peaked after 2 h of rest with an 18-fold increase compared with the pre-exercise value. No changes were found in the concentrations of IL-1beta, tumour necrosis factor (TNF)alpha, IL-15 and macrophage inflammatory protein (MIP)-1beta, and the concentrations of IL-8 and MIP-1alpha were below detection limits. 4. The results suggest that very early events in exercise trigger the release of IL-6, and that the cytokine response to exercise has similarities to that observed after trauma.

Adult↗

PubMed1998

Evidence that interleukin-6 is produced in human skeletal muscle during prolonged running.

1. This study was performed to test the hypothesis that inflammatory cytokines are produced in skeletal muscle in response to prolonged intense exercise. Muscle biopsies and blood samples were collected from runners before, immediately after, and 2 h after a marathon race. 2. The concentration of interleukin (IL)-6 protein in plasma increased from 1.5 +/- 0.7 to 94.4 +/- 12.6 pg ml-1 immediately post-exercise and to 22.1 +/- 3.8 pg ml-1 2 h post-exercise. IL-1 receptor antagonist (IL-1ra) protein in plasma increased from 123 +/- 23 to 2795 +/- 551 pg ml-1, and increased further to 4119 +/- 527 pg ml-1 2 h post-exercise. 3. The comparative polymerase chain reaction technique was used to evaluate mRNA for IL-6, IL-1ra, IL-1beta and tumour necrosis factor (TNF)-alpha in skeletal muscle and blood mononuclear cells (BMNC) (n = 8). Before exercise, mRNA for IL-6 could not be detected either in muscle or in BMNC, and was only detectable in muscle biopsies (5 out of 8) after exercise. Increased amounts of mRNA for IL-1ra were found in two muscle biopsies and five BMNC samples, and increased amounts of IL-1beta mRNA were found in one muscle and four BMNC samples after exercise. TNF-alpha mRNA was not detected in any samples. 4. This study suggests that exercise-induced destruction of muscle fibres in skeletal muscles may trigger local production of IL-6, which stimulates the production of IL-1ra from circulating BMNC.

Adult↗

PubMed1998

Prospective randomised study comparing tacrolimus (Prograf) and cyclosporin (Neoral) as primary immunosuppression in cadaveric renal transplants at a single institution: interim report of the first 80 cases.

As part of an ongoing study, 80 patients undergoing cadaveric renal transplantation were randomised to receive either Prograf [PTT (patients receiving Prograf); n = 40]- or Neoral [NTT (patients receiving Neoral); n = 40]-based immunosuppression as part of a triple therapy regimen. Prograf was commenced at a dose of 0.2 mg/kg per day and Neoral at 8 mg/kg per day. Both groups received identical azathioprine and corticosteroid regimens. Trough levels for Prograf were maintained between 5 and 15 ng/ml and for Neoral between 100 and 200 ng/ml. During the 3-month follow up 40% of PTT and 33% of NTT experienced biopsy-proven acute rejection. In each group 81% of rejection episodes were classified as either borderline or grade 1. The median 3-month serum creatinine levels were 128 mumol/l and 135 mumol/l, respectively, for PTT and NTT. Six grafts were lost in the NTT group including three deaths with functioning grafts whilst none were lost in the PTT group (chi 2, P < 0.02). The prevalence of other complications was similar for the two groups. We conclude that Prograf represents an effective and safe therapy as a primary immunosuppressive agent following cadaveric renal transplantation and appears to have a similar side-effect profile to Neoral.

Adult↗

PubMed1998