Short-term calorie restriction and refeeding differently affect lipogenic enzymes in major white adipose tissue depots of young and old rats

The metabolic effects of short-term calorie restriction (SCR) and subsequent refeeding were compared in different white adipose tissue (WAT) depots of young (5-month old) and old (24-month) male Wistar rats. The animals were subjected to a 40% calorie restricted diet (i.e. 40% lower food supply than of control rats) for 30 days, and then re-fed for 0, 2, or 4 days. WAT samples from perirenal (pWAT), epididymal (eWAT), and subcutaneous (sWAT) depots were analysed for the enzymatic activities of ATP-citrate lyase (ACL), fatty acid synthase (FAS), and glucose-6-phosphate dehydrogenase (G6PD). The total WAT mass almost doubled in old rats, however, aging did not alter the relative proportions of the major regional fat depots. Serum leptin concentration was prominently higher in old rats, in which SCR resulted in less suppression of leptin level than in young animals, whereas refeeding increased leptin concentration in young, but not old, rats. In young rats refeeding elevated leptin gene expression only in pWAT, while in old rats the expression was induced first in eWAT, and later in pWAT. A prominent age-related decrease of ACL and FAS activities, but not of G6PD activity, was found in all the studied WAT depots. In young control rats, ACL activity was highest in pWAT, FAS activity was similar in all WAT depots, and G6PD activity was lowest in eWAT. In old rats, the enzymatic activities were lower in eWAT than in the other depots. The patterns of response to SCR and refeeding varied by age and WAT location. SCR stimulated ACL activity in pWAT but not in other depots of young rats, while FAS activity in pWAT and sWAT did not change in young and decreased in the old animals. Among the studied depots, pWAT was most responsive to refeeding in both age groups. In conclusion, SCR in old rats, as compared to the young, may be accompanied by reduced 'rebound effect' upon returning to unrestricted diet.

Human peripheral blood CD8+ CD28- T cells of renal allograft recipients do not express FOXP3 protein

INTRODUCTION

In recent studies, the FOXP3 molecule has been suggested to be a marker of a suppressor subset of human CD8+ CD28- T cells based on correlations between the level of its mRNA and allograft function. Because this transcriptional factor produces a protein, we suggest that these correlations should focus on the FOXP3 protein. The aim of our study was to evaluate whether FOXP3 protein was present in cells of the CD8+ CD28- population in the peripheral blood of renal allograft recipients and whether the level of CD8+ CD28- FOXP3+ cells correlated with allograft function.

METHODS

The study was performed on 30 renal allograft recipients with uneventful stable courses (n=18) or biopsy-proven chronic rejection (n=12). The immunosuppression was based on cyclosporine (n=12) or rapamycin (n=9). Peripheral blood mononuclear cells isolated from recipient blood samples were labeled with anti-CD8 and anti-CD28 MAbs conjugated with fluorochromes. After incubation, washing, and labeling using a PE anti-human FOXP3 Kit, we determined the percentage of cells by flow cytometry.

RESULTS

FOXP3 protein expression was not observed either in the CD8+ CD28- population, or the whole populations of CD8+ or CD28- cells among patient groups.

CONCLUSIONS

The expression of FOXP3 protein in CD8+ CD28- cells seems to be of a questionable value as a diagnostic tool for allograft function, it is probably not a marker for the CD8+ CD28- T cell subset.

Beta 3 integrin expression on T cells from renal allograft recipients

Recent studies emphasize the paramount significance of beta 3 integrin in cell adhesion and homing, which may be particularly relevant in cancer progression and metastasis. In contrast, the presence and potential role of beta 3 on human T cells is practically unknown. We show that T cells can express significant amounts of alpha-beta 3 integrin (CD41/CD61), and the expression of alpha(v)-beta 3 (CD51/CD61) remains very low. T-cell beta 3 integrin is probably transferred by platelet-derived microparticles.

Parametric generation of forward and phase-conjugated spin-wave bullets in magnetic films

We show experimentally as well as by numerical simulation that interaction of a linear two-dimensional spin-wave packet with quasiuniform pulsed pumping leads to the formation of strongly self-focused nonlinear spin-wave bullets propagating in both forward and reversed directions. The focusing of the reversed, phase-conjugated wave bullet is stronger than that of the forward one, because not only the nonlinear four-wave self-focusing effect but also linear focusing due to two-dimensional phase conjugation contributes to the focusing of the reversed bullet.

New insights into the possible role of bacteriophages in transplantation

Due to the increasing prevalence of drug-resistant bacterial infections in the "post-antibiotic era," bacteriophages (bacterial viruses, BP) may be useful to administer to transplant recipients without exposing them to an increased risk of rejection, which occurs consequent to some viral infections. Herein we present evidence that at least some coliphages (T4) do not pose such risk. Interestingly, they may produce immunosuppressive effects extending transplant survival. Our data suggest that BP may be used in clinical transplantation to treat drug-resistant bacterial infections and perhaps as an adjunct to immunosuppressive therapy.

Involvement of beta2-microglobulin in CD69 expression on T cells

Beta2-microglobulin (beta2M) is the light chain of the class I HLA molecule. The serum level of beta2M is elevated in various diseases including lymphoma, inflammation, viral infections and chronic renal dysfunction. The present study addressed the possible influence of beta2M on T lymphocyte activation in vitro. Peripheral blood mononuclear cells from a group of 17 healthy subjects were examined. Stimulation with OKT3 and fibronectin in combination with 30 mg beta2M/dl resulted in a two-fold increase of cell proliferation. A similar effect was observed when OKT3 and collagen I were applied as well as when OKT3 and collagen IV were used as costimulation to T cells. The CD69 expression, measured by flow cytometry was significantly enhanced above the control level (1.52 +/- 1.03% vs 33.21 +/- 20.26%, p<0.01, control group and 30 mg beta2M/dl, respectively). Together, these observations suggest that beta2M may play a role in modulating lymphocyte proliferation, possibly through modification of the CD69 molecule.

[Biochemical risk factor for atherosclerosis in young men. Preliminary report]

Atherosclerotic damage of cardiovascular system, including kidneys, is an increasing problem not only in the modern cardiology but also in nephrology and dialysotherapy. The purpose of our study was to evaluate the frequency of particular biochemical risk factors for atherosclerosis (RFfA) in young men being over-pressed with psychological stress because of decisive character of their professional job. There were 68 men in mean age 33.3 +/- 7.4 years, being employed in the state administration for mean 10.9 +/- 7.5 years. On the basis of the results of environmental questionnaire the studied group was divided into two subgroups: subgroup A "passive" (30 persons) which was physically passive (employed in the administration) and subgroup B "active" (38 persons) whose professional job was connected with physical activity. The following biochemical RFfA in the blood were examined: cholesterol and its fractions, triglycerides, urea acid, glucose, fibrinogen, C-reactive protein, homocysteine and antibodies against Chlamydia pneumoniae. The results were as follows: total cholesterol above 200 mg/dl in 63%, LDL cholesterol above 130 mg/dl in 60% and HDL cholesterol below 50 mg/dl in 31% of men. Among "new" RFfA we found "cardiological" (above 0.2 mg/dl) levels of CRP almost in 25% of the whole group. There were no statistically significant differences with respect to the studied RFfA between "active" and "passive" group. On the basis of these preliminary results we presume, that potentially healthy men over-pressed with psychological stress because of decisive character of their professional job, are characterized--independently on the proclaimed physical activity--by high frequency of risk factors for premature atherosclerosis.

[Diagnostic and therapeutic problem of infected arteriovenous fistula for hemodialysis-case report]

On the case of 48 old patient with chronic renal failure, treated with repeated hemodialyses, we described diagnostic and therapeutic problems of infected arterio-venous fistula of severe clinical course and rare epidemiology (Staphylococcus warneri). Special attention was paid to the difficulties in the confirmation of bacterial etiology of this infection as well as practical usefulness of ultrasonography in the monitoring of clinical course and therapy of infected arteriovenous fistula.

[Doppler sonography assessment of renal arteries against the cardiovascular risk factors in young men--preliminary report]

The purpose of this study was to find out a relationship between cardiovascular risk factors (CVRF) and abnormal results of Duplex Doppler sonography (DD), suggesting renal artery stenosis (RAS). The group of 30 potentially healthy men (age: 35.5 +/- 7.9) randomly selected from population of 200 young men, underwent DD of renal arteries. Abnormal results of DD study, suggesting RAS were found in 19 of 30 men (63%). In this group, occurrence of 3 or more CVRF was significantly higher (15/19) than in the group with normal results of DD (5/11; p < 0.05). The significantly higher (77%; p < 0.05) occurrence of the abnormal DD and the significantly longer (p < 0.001) duration of habitual tobacco smoking were also found out in the group with RR > or = 130/85 mm Hg, in comparison to the group with RR < 130/85 mm Hg. Emphasizing preliminary character of this study and the need of confirmation on larger population, it seems reasonable to consider the assessment of renal arteries with DD in the population of men with cardiovascular risk factors.

[Coping style with stress against chosen biochemical risk factors of atherosclerosis in potentially health men]

The aim of the study was to assess the relationship between some psychological variables and biochemical and inflammatory risk factors for atherosclerosis in healthy men. Studied group, 70 potentially healthy men randomly selected from the group of 200 potentially healthy men previously screened for atherosclerosis risk factors, workers of state administration in mean age of 33.3 +/- 7.4 years, with mean duration of job employment 10.9 +/- 7.5 years, was divided into two groups of 35 persons each, according to physical activity: "active" and "passive". For psychological examination we used Coping Inventory for Stressful Situations Questionnaire (CISS) and State and Trait Anxiety Inventory (STAI). "Passive" group had better results in scales: I--task oriented coping; II--emotion oriented coping; III--avoidance oriented coping; IV--distraction. "Active" group had better results in scales: IIIB--social diversion, LS--anxiety as a state; LC--anxiety as a trait. These differences were not statistically significant. Among biochemical atherosclerosis risk factors mean levels of LDL, triglycerides (TRIG) and C-reactive protein (CRP) were higher in "passive" group. HDL was higher in "active" group. There were no statistical significant differences between both groups, too. Statistical analysis showed positive correlation of LC with scale II in both groups (r > 0.6, p < 0.002). In "passive" group significant negative correlation was found between: TRIG and III (r = -0.562; p = 0.025); TRIG and IIIB (r = -0.497; p = 0.036). LS correlated positively with LC (r = 0.476; p = 0.046) and scale IIIA correlated positively with scale IIIB (r = 0.550; p = 0.018). In "active" group positive correlation was found between: CRP and LC (r = 0.476; p = 0.021) and negative correlation between CRP and scale I (r = -0.437; p = 0.037); LS correlated positively with IIIA (r = 0.443; p = 0.039) but LC correlated negatively with scale I (r = -0.424; p = 0.049). We conclude, that men using in stressful situations task oriented coping style are less prone for atherosclerosis. This hypothesis needs to be confirmed on the larger population of potentially healthy men.

[Enhanced neuroticism in relation to cardiovascular risk factors in men]

Chronic stress is well known as a cardiovascular risk factor in men. There are few reports referred to the relationship between cardiovascular risk factors and level of neuroticism in the psychological examination. We analysed 77 healthy men in mean age of 33.3 +/- 7.4 years being at risk of chronic professional stress. Level of neuroticism was examined by Geras scale and expressed as: low (1-4 sten)--group 1, mean (5-6 sten)--group 2 and high (7-10 sten)--group 3 level of neuroticism. The common biochemical, clinical and environmental cardiovascular risk factors were examined. In the whole group of 77 probands we identified 24 (31%) (group 2) and 10 (13%) (group 3) persons with mean and high level of neuroticism. In the group 2 we find the highest cholesterol (222.7 +/- 39.4 mg/dl), LDL cholesterol (147 +/- 35.1 mg/dl, triglicerydes (144.9 +/- 93.8 mg/dl) and apolipoprotein B (1.11 +/- 0.31 g/l) levels statistically higher than in the other group of neuroticism. In group 3 we find the highest glucose (96.5 +/- 7.4 mg/dl) and fibrinogen (353.8 +/- 39.2 mg/dl) levels. The worst results of the environmental inquiry were obtained in the group 2 (obesity (BMI > 30 kg/m2) in 25%, hypertension in 12.5%, nicotinism in 54%, low physical activity in 79% and positive to cardiovascular disease family history in 91%). Because we found correlation mostly in the group of mean level of neuroticism these results must be confirmed in the larger group of probands using other psychological tests.

[Report from the seventh international course on peritoneal dialysis, Vicenza, Italy, May 23-26, 2000]

This report is devoted to the Seventh International Course on Peritoneal Dialysis with special interest to the place of peritoneal dialysis in so called "healthy" start of renal replacement therapy, more biocompatible dialysis solutions as well as limitations in the estimation of peritoneal dialysis adequacy using Kt/V for urea and weekly creatinine clearance.

[Stress as a risk factor for cardiovascular disease]

This review refers to the experimental and clinical investigations on stress as a important risk factor of cardiovascular diseases.

[Goodpasture's syndrome--continuing clinical problem]

On the case of too late diagnosed Goodpasture's syndrome with further fatal clinical course necessity of early diagnosis and aggressive immunosuppressive therapy is stressed.

[The prolonged asystole during head down tilt test: prognostic significance and therapy]

The head up tilt test is a worthy of acknowledgment and widely accepted tool used in diagnosing patients with syncope of unknown origin. In some cases tilting provokes asystole lasting even several tens of seconds. Not long ago this kind of vasovagal reaction was being associated with appearance of syncope combined with body injures. The prognostic significance of asystole during head-up tilt test and the safe and efficacious way of therapy in such cases hasn't been established yet. There were three cases of vasovagal reaction, resulting in asystole, described in order to show a large number of diagnostic and therapeutic problems related to the discussed syndrome. The presentation of actual views on diagnosing and therapy of patients with vasovagal syndrome, as a matter of fact is a synthesis of published results of clinical studies and its aim is to be more objective about so many obliging theories.

[Influence of trimetazidine on echocardiography parameters and free radical stress index in coronary artery disease and end-stage renal failure patients treated by hemodialysis: preliminary communication]

The aim of the study was the assessment of the influence of trimetazidine (TMZ) on echocardiography parameters and oxidative stress markers in hemodialyzed patients with coronary artery disease. The studies were carried out in 9 patients group before and after 3 months of TMZ treatment in doses 3 x 20 mg. Additionally we measured MDA concentration in the blood, as a oxidative stress marker, before and after 2 and 3 months of TMZ treatment. At the start of the study impairment of relaxation as a sign of diastolic dysfunction was detected. This abnormality persisted up to the end of the study. After 3 months of TMZ treatment we observed elevation of ejection fraction from 59.17 +/- 5.99 to 65.33 +/- 8.7% (p = 0.05). Also occurred statistically significant decrease in MDA level after 2 (0.674 +/- 0.029 vs 0.627 +/- 0.034; p < 0.001) and 3 (0.674 +/- 0.029 vs 0.567 +/- 0.063 mumol/L; p = 0.001) months of TMZ treatment. Significant improvement of the left ventricular function and decrease of MDA levels in the blood might be due to intracellular mechanisms of TMZ activity. There were no side effects of the drug in hemodialyzed patients.

[The evaluation of expression of T-lymphocytes and NK cell surface receptors in women with threatened miscarriage]

OBJECTIVES

Recent studies emphasise an important role of immunological mechanisms in pregnancy maintenance. Therefore, unravelling mechanisms regulating placentogenesis are critical to understanding the pathogenesis of recurrent spontaneous abortion.

MATERIALS AND METHODS

We studied 49 women with threatened abortion and 24 healthy pregnant women. In addition, we studied 17 women with the history of recurrent spontaneous abortion and 10 healthy nonpregnant women in reproductive age with the previous successful pregnancy outcome. CD3, CD45 RO, CD4, CD8, CD16 expression on peripheral blood lymphocytes were studied using flow cytometry.

RESULTS

We determined that there is significantly higher CD4 expression in pregnant recurrent aborters compared to control (p < 0.05). Pregnant recurrent spontaneous aborters, with the successful pregnancy outcome have significantly lower CD16 expression compared to those, who abort (p < 0.05).

CONCLUSION

Our studies may indicate that T cell and NK cell can be involved in the pathogenesis of pregnancy loss.

[Late ventricular potential as a risk factor for sudden cardiac death in chronically hemodialysed patients]

Severe heart arrhythmias are common in patients with irreversible renal failure on chronic hemodialysis. Late ventricular potentials revealed on the signal-averaged electrocardiogram were found to have predictive value of sudden cardiac death in general population of patients with coronary artery disease or nonischemic cardiomyopathy. The value of this method in hemodialysis patients is presented and discussed.

[Successful aorto-coronary bypass in the care of unstable heart ischemia in the course of irreversible renal failure treated by repeated hemodialyses]

Cardiovascular diseases especially coronary heart diseases are responsible for high rate (about 50%) of deaths in the group of patients with irreversible renal failure treated with hemodialysis. Coronary artery bypass grafting is recommended as a method of choice in symptomatic patients with coronary heart disease being the candidate for renal transplantation. On the basis of recently observed patient successfully treated with coronary artery bypass grafting pre- and and postoperative dialysis protocol is presented and discussed with literature.

[Influence of alphacalcidole on selected markers of the bone turnover in hemodialysed patients with secondary hyperparathyroidism]

In 19 chronically hemodialysed patients (11M + 8F, mean age 52 +/- 15 yrs) with secondary hyperparathyroidism (sHP), selected markers of bone turnover in the course of pulsative treatment with alphacalcidol were evaluated. Alphakalcidol was given 3 times per week after hemodialysis. Every 3-rd month of therapy we measured serum concentration of procollagen type I carboxy-terminal propeptide PICP as a marker of bone formation as well as carboxy-terminal telopeptide type I collagen ICTP and iPTH as markers of bone resorption. The results were as follows. During 12 months of controlled treatment of sHP with alphacalcidol, statistically significant decrease of serum iPTH (from 393 +/- 145 pg/ml to 246 +/- 172 pg/ml) with simultaneous increase of serum PICP (from 235 +/- 168 mg/L to 414 +/- 168 mg/L) were obtained. Serum ICTP levels, although significantly increased in comparison to normal values, did not change under influence of alphacalcidol therapy. The mean weakly dosis of alphacalcidol of 2.27-2.39 mg successfully suppressed process of bone resorption evaluated by iPTH giving predominance to bone formation expressed by PICP. Serum levels of ICTP appeared to be of no value in monitoring treatment efficacy of alphacalcidol in hemodialysed patients with secondary hyperparathyroidism.

[Marfan's syndrome: diagnosis and treatment]

The Marfan syndrome is an autosomal dominant inherited disorder of connective tissue with pleiotropic manifestation involving mainly the cardiovascular, ocular, skeletal and pulmonary systems. Aortic root dilatation and heart valve lesions are particularly common and presage a reduced life expectancy. Over the ensuring 20 years, however, treatment to prevent or correct the cardiovascular complications of the syndrome has changed dramatically--life expectancy for patients with the Marfan syndrome has increased > 25%. Reasons for this dramatic increase may include (1) an overall improvement in population life expectancy, (2) benefits arising from cardiovascular surgery, and (3) greater proportion of milder cases due to increased frequency of diagnosis. Cardiovascular surgery, both prophylactic and emergent, has become accepted treatment for aortic aneurysm, and aortic dissection. In addition, beta-adrenergic receptor antagonists have gained wide acceptance as potential agents for delaying aortic expansion and progression to rupture or dissection. In conclusion, medical therapy is also associated with an increase in probable survival.

Lymphocyte interactions with extracellular matrix proteins and endothelium in renal allograft recipients

Recent data indicate that extracellular matrix (ECM) proteins can provide costimulatory signals during the process of T cell activation. Those proteins accumulate in situ during allograft rejection; therefore, it may be expected that local ECM: T cell interactions may be relevant in the immunopathology of rejection. T cell adhesion from allograft of recipients with stable renal function (RAR-S) and patients with biopsy-proven chronic rejection (RAR-CH) to ECM proteins (collagen type IV, fibronectin, elastin) was measured. Furthermore, T cell: endothelial interactions in vitro were studied. Adhesion of PHA-activated T cells from both groups of allograft recipients to fibronectin, collagen type IV and elastin was significantly lower than in healthy blood donors. Moreover, similar pattern of activity was observed when T cell attachment to resting and activated endothelium was studied. There were no significant differences in the number of circulating CD45RO and CD4 positive T cells. We observed a higher (although not significantly) adhesion of the T cells to resting human dermal microvascular endothelial cells (HMEC) in the chronic stages of rejection, which can suggest that the immunosuppressive protocol used in the treatment of chronic rejection is insufficient to control immunopathologic phenomena occurring in that process. Therefore, it may be argued that too low immunosuppression can be one of the factors responsible for the development of this complication.

Depressed immune surveillance against cancer: role of deficient T cell: extracellular matrix interactions

Although T cells infiltrate malignant tumors, the local immune response is usually inefficient and tumors escape destruction. While extracellular matrix proteins strongly costimulate T cell responses in normal individuals, our studies indicate that peripheral blood T cells from cancer patients and tumor infiltrating cells respond poorly or are resistant to stimulative signals mediated by collagen I and IV and fibronectin. Moreover, the adhesive properties of cancer T cells are markedly depressed. Those functional deficiencies are paralleled by variable deficits in integrin and non-integrin T cell receptors for extracellular matrix. Immunotherapy with BCG causes a dramatic but transient increase in T cell: ECM interactions.

Cladribine (2-chloro-deoxyadenosine, CDA): an inhibitor of human B and T cell activation in vitro

We have previously shown that the novel immunosuppressive agent cladribine (CDA) inhibits human T and B cell lymphoproliferative responses and immunoglobulin synthesis in vitro, yet appears to be particularly efficacious as an inhibitor of B cell responses. We now report the effects of CDA on the human mixed lymphocyte reaction and on expression of T and B cell activation markers. CDA produced a significant inhibition of lymphocyte proliferation in human mixed lymphocyte reactions at a concentration of 10 nM. At concentrations of 10-100 nM the drug inhibited phytohaemagglutinin-induced expression of CD25 and HLA-D (by approximately 50%), but not phorbol myristate acetate-induced expression of CD69 on purified human T cells. At a concentration of 10 nM CDA totally abolished Staphylococcus aureus Cowan-induced expression of CD25 on purified B cells. These findings confirm that CDA is a potent immunosuppressive agent with some selectivity towards B cells. The drug may have potentially wide applications in clinical immunosuppression.

Immunosuppression inhibits switch from naive to memory phenotype in human T lymphocytes

Recently, human T cells have been divided into memory (antigen-primed) and naive (unprimed) subsets, which vary in phenotype and function. Immunosuppressive drugs and heparin have been found to inhibit PHA-induced in vitro switching from naive to memory cell phenotype in a process that is at least partly independent of cell proliferation. Furthermore, T cells isolated from immunosuppressed renal allograft recipients were deficient in their in vitro PHA-induced transition from naive to memory phenotype.