The effect of smoking on peripheral insulin sensitivity and plasma endothelin level.

OBJECTIVES: The aim of the present study was to investigate the effect of smoking on peripheral insulin effectiveness. METHODS: Seven healthy volunteers, nonsmokers, of mean age 39.6 +/- 7.1 Years and mean BMI 22.65 +/- 11.98 kg/m2, without family history of diabetes mellitus, with normal blood pressure participated in the study. All the parameters were studied twice - at baseline as well as after smoking (4 cigarettes per one hour). The study was performed in three days: at the first day we studied peripheral insulin effectiveness (M) in vivo by the artificial endocrine pancreas (Biostator), using the euglycaemic hyperinsulinaemic clamp technique, and insulin-receptor binding on circulating mononuclear blood cells; at the second day - the same parameters after one-hour smoking during the third hour of clamping; at the third day - plasma endothelin level, blood pressure and heart rate at baseline and after one-hour smoking. RESULTS: There was a significant decrease in glucose utilization during the second clamp test, when the volunteers smoked during the third hour as compared to the test at baseline (p=0.04). This was accompanied by a significant decrease in insulin receptor affinity (p=0.04). Systolic blood pressure and heart rate increased significantly after one-hour smoking (p=0.03 and p=0.001, respectively). Plasma endothelin level increased significantly after smoking (from 0.62 +/- 0.15 pg/ml to 2.05 +/- 1.67 pg/ml, p=0.03). CONCLUSION: Our results demonstrate that smoking decreases peripheral insulin sensitivity reducing insulin receptor affinity. We have confirmed that smoking increases plasma endothelin level, which probably by causing vasoconstriction and consequent tIssue hypoxaemia could decrease peripheral glucose utilization. We consider that smoking could also have a direct effect on insulin receptor affinity, thus leading to decreased peripheral insulin effectiveness.

L-carnitine consecutively administered to patients on hemodialysis improves beta-cell response.

Eight patients with end stage renal disease (ESRD) on chronic hemodialysis (CHD) treatment were supplemented with 1 g L-carnitine intravenously (i.v.) after each dialysis session for one month. A Tolbutamide test was done and blood sugar (BS), serum C-peptide (CP) were measured at 0, 20 and 60 minutes, as well as the plasma L-carnitine level before and after treatment. Delta CP and the area under CP curve were ascertained. After L-carnitine application delta CP was significantly increased (1.33 +/- 0.63 vs. 2.24 +/- 1.0 nmol/L; p<0.05) and also the area of the stimulated secretion under the CP curve (14.93 +/- 11.11 vs. 36.88 +/- 25.36 nmol/L x 60 min.; p<0.05). The fasting BS-level was significantly lower after the treatment--3.85 +/- 0.43 vs. 4.76 +/- 1.02 mmol/L; p<0.05 and plasma L-carnitine level significantly increased (72.8 +/- 43.2 vs. 35.2 +/- 18.3 mcmol/L; p<0.05) Improving the oxidative processes in peripheral tissues, L-carnitine increases the peripheral effectiveness of insulin and relieves the overstretched beta-cell apparatus.

Plasma levels of branched chain amino acids in patients on regular hemodialysis before and after including a high-protein supplement in their diet.

Chronic renal failure (CRF) patients on hemodialysis have low plasma level of the branched chain amino acids (BCAA) leucine, isoleucine, and valine. The abnormalities in the plasma amino acid pool can be corrected with appropriate high-protein supplements. The present study was designed to evaluate the effect of a balanced protein nutritional supplement on the plasma level of BCAA. Twenty eight CRF patients who received hemodialysis treatment three times in a week were enrolled in the trial. The initial plasma levels of BCAA were as follows--leucine 15.46 +/- 3.88 mcg/ml, isoleucine 9.08 +/- 1.97 mcg/ml, and valine 24.05 +/- 5.06 mcg/ml. For a period of 6 months the patients received a balanced nutritional supplement (58-59% total protein content, leucine--8.6, isoleucine--4.8, and valine--5.7 g/100 g protein) on the day of hemodialysis at a dose 1.0 g/kg body weight. Three months after beginning of supplementation the plasma level of BCAA was found to be elevated--leucine by 36% (P < 0.001), valine by 30% (P < 0.001), and isoleucine by 27% (P < 0.001). The body mass index of the patients was also above the initial values. The plasma BCAA levels were maintained high until the sixth month from the beginning of trial and even a month after withdrawal of the supplement. The results obtained allow us to recommend inclusion of protein supplements with balanced amino acid content in the diet of these patients.

Evolution of renal replacement therapy in Central and Eastern Europe 7 years after political and economical liberation. Central and Eastern Europe Advisory Board in Chronic Renal Failure.

PURPOSE OF THE STUDY: The conditions of renal replacement therapy (RRT) were very poor in the countries located in Central and Eastern Europe (CEE) when they were members of the so-called 'socialist bloc'. The aim of the present analysis was to document the impact of the socioeconomic changes on dialysis therapy in the CEE countries. DESIGN: This was a special survey with the participation of 12 CEE countries, with data obtained through national registries (with the exception of Russia). RESULTS: During the period 1990-1996 the number of haemodialysis units increased by 56% and the number of centres performing peritoneal dialysis by 296%. The number of patients increased respectively by 78% (haemodialysis) and 306% (peritoneal dialysis). The percentage of patients with diabetic nephropathy and elderly patients rose dramatically during this period. One of the main reasons of such expansion was the rapid development of peritoneal dialysis programmes in the majority of the CEE countries. The introduction of modern haemodialysis machines and a wider choice of different dialysers and concentrates permitted individualization of dialysis procedures. These points and the wider use of erythropoietin had a positive influence on quality of life and treatment outcome. There was also a notable increase in the number of transplant centres, but less so of the number of transplanted patients. CONCLUSION: Renal replacement therapy experienced a major expansion in the CEE countries. Despite the progress achieved, the level of RRT is not yet completely satisfactory in most CEE countries.

[A computer program for the drug dosage of patients with chronic kidney failure]. / Kompiuturna programa za dozirane na medikamenti pri bolni s khronichna bubrechna nedostatuchnost.

On the basis of the formula Mt = Mo.e-(Cl/Vd).t, a computer program was developed for estimating the maintenance drug dose in patients with chronic renal failure, depending on the creatinine clearance levels and the body mass. The hypothesis of the intact nephron and the presumption that in chronic renal failure the extrarenal clearance of the drugs does not change is considered a precondition. Any drug whose distribution volume and extrarenal clearance are known may be implicated in the program. The program may also help to determine the additional dose after hemodialysis, depending on the duration of the dialysis and the dialysis clearance of the drug.

[An analysis of the survival and death rate of patients on periodic hemolysis treatment at the Hemodialysis Center of the Medical Academy in 1971-1987]. / Analiz na prezhiviaemostta i smurtnostta na bolnite na periodichno khemodializno lechnie v Tsentura po khemodializa pri MA za perioda 1971--1987 g.

For a period of 17 years a total of 377 patients have been on hemodialysis treatment--242 men (64.2 per cent) and 135 women (35.8 per cent). During the first nine years the difference between men and women was significant (71.6 and 28.4 per cent respectively), in the next 8 years however it fell--accordingly 58.6 and 41.4 per cent. The age of patients on intermittent dialysis program was significantly increased--from 37.43 years during the first period, to 46.56 years during the second. Although almost all contraindications for dialysis treatment gradually dropped off, patient death rate has been constantly decreasing and in the last five years is steadily below 10 per cent. Survival is increasing and for the last year averages 5 years. The primary cause of death of patients on intermittent hemodialysis are cardiac complications--47.2 per cent of the decreased 176 patients.

[The effect of chronic kidney failure on electroneurographic changes in patients on hemodialysis treatment]. / Vliianie na khronichnata bubrechna nedostatuchnost vurkhu niakoi elektronevrografski promeni pri bolni na khemodializno lechenie.

Electroneurographic examination of n. medianus, n. ulnaris, n. tibialis and n. fibularis was performed in 23 patients (15 men and 8 women) at mean age 52.1 years and mean duration of hemodialysis treatment 42.1 months. All patients had electroneurographic symptoms of peripheral polyneuropathy. The duration of hemodialysis treatment had no effect on the severity of the neurologic injury. Significant correlation was found between the severity of anemia and the peripheral nerve injury. According to the authors' data, essential for the development and severity of the uremic polyneuropathy was also the severity of the uremic syndrome.

[Peritonitis in patients treated by continuous ambulatory peritoneal dialysis]. / Peritonit pri bolni, lekuvani s produlzhitelna ambulatorna peritonealna dializa.

With the present study the authors set themselves the task to compare the number of peritonitis episodes in patients treated with two types of systems: "Sorin-Biomedica" and "Travenol-(UV-XD)", in which disinfection of the connecting devices is achieved accordingly with chemical agents and with ultraviolet irradiation. Eleven patients have been observed from August 1984 through February 1989. The total duration of treatment was 156 months. Twenty one peritonitis episodes were observed--15 with "Sorin-Biomedica" system and 6 with "Travenol-(UV-XD)" system--an average of one episode in 4 1/2 months with the former system and one episode in 14.7 months with the latter. It is pointed out in conclusion that the "Travenol-(UV-XD)" system with ultraviolet disinfection has significantly reduced the incidence of peritonitis at the dialysis center where the authors work.

[Effect of autonomic pathology in uremia on the blood pressure during hemodialysis]. / Vliianie na uremichnata vegetopatiia vurkhu arterialnoto naliagane po vreme na khemodializa.

The state of the vegetative nervous system was studied by the deep respiration test, Valsalva test and the orthostatic test in 12 patients with terminal chronic renal failure and hypotension in the course of hemodialysis, 12 patients with stable hemodynamics in the course of hemodialysis and 12 healthy controls. By the deep respiration test the mean change of the cardiac rate in the patients with hypotension is significantly lower than that in the healthy controls (p less than 0.001) and that of the normotonic patients on hemodialysis (p less than 0.01). In the dialyzed normotonic patients the change of the cardiac rate is significantly lower than that in the healthy controls (p less than 0.02). Similar results are achieved with the Valsalva test. The impairment of the vegetative nervous system is considerably better expressed in the hypotensive patients. The proposed tests are noninvasive, easy to perform and give reliable information for the affection of the vegetative nervous system.

[Prevention and treatment of cardiac rhythm disorders during hemodialysis]. / Profilaktika i lechenie na ritumnite narusheniia na surdechnata deinost po vreme na khemodializa.

16 patients with chronic renal failure and cardiac rhythm disorders which appear or aggravate in the course of hemodialysis were followed up. The most frequent cause for the appearance of arrhythmia in the course of hemodialysis is the dialyzing solution containing 2 mmol/l potassium. Some predisposing factors such as age, cardiac failure also play a role. The prophylaxis of these rhythm disturbances can be carried out by increasing the potassium content of the dialyzing solution up to 3.0-3.5 mmol/l. This does not lead to statistically significant increase of the predialysis potassium serum concentration but after the dialysis the serum potassium concentration increases statistically significantly (4.01 mmol/l against 3.29 mmol/l, p less than 0.05). This dialyzing solution is recommended also for the treatment of digitalized patients in order to prevent digitalis intoxication.

[Electrocardiographic changes in patients with chronic kidney failure treated by periodic hemodialysis]. / Elektrokardiografski promeni pri bolni s khronichna bubrechna nedostatuchnost, lekuvani s periodichna khemodializa.

The data of the analysis of 245 ECGs of 110 patients with chronic renal failure treated by periodic hemodialysis are presented. The lengthening of the electrical systole (the PQ interval) is the most frequent ECG finding - in 70% of the patients. It is followed by left ventricular hypertrophy - in 33.6%, ischemic changes - in 29.1%, rhythm disturbances - in 23.7%, conduction disorders - in 10.9% of the patients. The statistical analysis of the results shows that the lengthening of the electrical systole, the left ventricular hypertrophy and the rhythm disturbances are unfavourable prognostic signs. The normal ECG found only in 9.1% of the patients is a favourable prognostic sign.

[Electrocardiographic changes in patients with chronic kidney failure treated by periodic hemodialysis]. / Elektrokardiografski promeni pri bolni s khronichna bubrechna nedostatuchnost, lekuvani s periodichna khemodializa.

The data from the analysis of 254 electrocardiograms of 110 patients with chronic renal insufficiency, treated with periodic hemodialysis are presented. The most often electrocardiographic change is the protraction of electric systole of the heart (interval QT). It is observed in 70% of the patients. Second comes the left ventricular hypertrophy with 33.6%, ischemic changes--in 29.1% rhythm disorders--in 23.7%, conduction disorders--in 10.9%. The statistical processing of the material reveals that the protraction of the electric systole of the heart, the left ventricular hypertrophy and rhythm disorders are unfavourable prognostic signs. The normal electrocardiogram present in only 9.1% of the patients, is a favourable prognostic sign. It could be one of the criteria for adequateness of hemodialysis treatment.

[Clinical testing of the Bulgarian Diamex dialyzers]. / Klinichno izprobvane na bulgarskite dializatori "Diameks".

The Bulgarian dialyzers "Diamex" were clinically tried as well as original patterns of the firm Fresenius--"Hemaflow" in 28 patients from the Centre of hemodialysis at the Medical academy. The results obtained for the clearances of Bulgarian dialyzers (urea clearance--2.61 ml/s, creatinine clearance--2.18 ml/s, clearance of inorganic phosphor--1.63 mg/s and clearance of uric acid--2.14 ml/s) and their ultrafiltration possibilities revealed no statistically significant difference as regards the data of the original patterns. No essential deviations in those indices with the first and third use of the dialyzers. The percentage of clearing during 4-hour hemodialysis, being 51.7% for urea, 48.2% for creatinine and 52.6% for uric acid, remains unaltered even with their third use. No allergic reactions have been established to the membrane in the groups of patients examined. It could be stress in conclusion that the Bulgarian dialyzers, according to quality and effectiveness, correspond to the original patterns could be used several times with no risk for the patients.