Systematical approach in evaluation of LC method for determination of raloxifene hydrochloride and its impurities employing experimental design

Method validation presents a detailed investigation of analytical method and provision of the evidence that the method, when correctly applied, produces results that fit to the purpose. In order to achieve the method validation scope efficiently, experimental design presents a very useful tool. The greatest benefits of such approach could be seen in robustness testing through the provision of very useful data about the control of the chromatographic system during the routine application. In this paper, robustness testing of the LC method proposed for the determination of raloxifene hydrochloride and its four impurities was done employing Plackett–Burman design. Applying this design, the effect of five real factors (acetonitrile content, sodium dodecyl sulfate content, column temperature, pH of the mobile phase and flow rate) on the corresponding resolution factors was investigated through twelve experiments. Furthermore, the insignificance intervals for significant factors were calculated and the parameters for system suitability tests were defined. Eventually, the other validation parameters were tested and the effectiveness of the proposed analytical method with a high degree of accuracy was confirmed.

The thyroid C cells of ovariectomized rats treated with estradiol

The structure and function of thyroid C cells were studied in ovariectomized (Ovx) adult female rats without and after chronic treatment with estradiol dipropionate (EDP). A peroxidase-antiperoxidase method was applied for localization of calcitonin (CT) in the C cells. Morphometric changes in their volume, nuclei, and relative volume density were evaluated in comparison with sham-operated control rats using a stereological method. The number of C cells was calculated. CT content in the sera was determined by radioimmunoassay. Ovariectomy (Ovx) led to a 21% increase in body weight ( P<0.005), while treatment of Ovx rats with EDP decreased body weight by 25% ( P<0.01). The immunoreactivity for CT in C cells of the Ovx rats was markedly increased. Significant decreases in the volume of C cells (by 13%; P<0.05) and serum CT (by 45%) were recorded, while the C cell number increased by 59% ( P<0.05) in relation to the corresponding controls. The treatment of Ovx rats with EDP caused conspicuous degranulation of the C cells. The cellular volume was increased by 11% and serum CT by 36% in comparison with Ovx animals. At the same time a decrease in C cell number by 29% ( P<0.05) was evident. It may be concluded that estradiol deficiency after Ovx reduced the synthesis and release of CT, while chronic treatment of these animals with EDP had a positive effect on the secretory activity of thyroid C cells.

[Surgical anatomy of the spleen with special emphasis on its segmental architecture]

The authors have analyzed several aspects of the surgical anatomy of spleen, commencing with historical data, topography, peritoneal ligaments, variations in shape, embryology and accessory spleens and venous system of the spleen. The mode of splenic artery branching, variations of polar arteries, and intra- and extraparenchymatous arterial anastomoses were thoroughly analyzed. It was shown that the spleen in most cases consists of five vascular territories (segments) clearly demarcated from each other, stressing the practical significance of splenic anatomy in segmental dearterialization of the spleen.

Epidemiology of end-stage renal disease and current status of hemodialysis in Yugoslavia

Maintenance hemodialysis (HD) in Yugoslavia started in the sixties and followed the dialysis trends in the Western Europe. However, in the last decade the development of renal replacement therapy (RRT) slowed down. In this report the epidemiology of ESRD from 1997-1999 and the survey of the status of HD treatment in Yugoslavia in 1999 are presented. Epidemiological data are obtained by the annual center questionnaires (response rate: 92.6 -94.2%). The survey of HD status is based on a specific questionnaire and covered 2108 patients (65%). At the end of 1999 there were 56 RRT centers in Yugoslavia treating 3939 patients: 3232 (82%) patients by HD, 248 (6.3%) by peritoneal dialysis, and 459 (11.7%) living with transplanted kidney. In a three year period, incidence of ESRD ranged from 108-128 pmp, point prevalence from 435-463 pmp and mortality rate from 20.7-17.9. Numerous refugee patients were treated over the last 10 years. Main causes of ESRD were glomerulonephritis (30%); Balkan nephropathy represented 11% and diabetic nephropathy 7% of all primary renal diseases. Cardiovascular and cerebrovascular diseases were the most common causes of death of RRT patients. Most centers are overcrowded and HD machines are worn out. Mean Kt/V was 1.19+/-0.08, mean URR% 58.8+/-7.4. The shortage of drugs prevented adequate management: 83% of HD patients had hemoglobin level less than 100 g/L but only 10.3 -17.8% were treated with rHuEpo; 64.5% of patients had phosphate levels higher than 1.7 mmol/L but only 33.5% used phosphate binders; 47% of patients had hypertension despite the antihypertensive therapy. The prevalence of hepatitis B remained unchanged (about 14%) in HD population during the last three years, but the prevalence of anti-HCV positive patients decreased (31-23%). In conclusion, there is a well developed dialysis service in Yugoslavia but insufficient conditions for adequate treatment.

[Effect of autogenic training on glucose regulation and lipid status in non-insulin dependent diabetics]

INTRODUCTION

The objective of this study was to examine the benefits of autogenic training in patients with type 2 diabetes and 40 diabetics treated with oral antidiabetic agents were assigned to receive autogenic training. Treatment effects on GHb levels, glycemia, lipids and lipid peroxidases were evaluated after 12 weeks.

RESULTS

Subjects demonstrated significant improvements of GHb level (8.94 +/- 2.21% vs. 7.9 +/- 2.395) (p < 0.005). Fasting glucose was significantly lower after treatment (11.6 +/- 6.1 mmol/l vs. 8.32 +/- 4.53 mmol/l) (p < 0.005). The serum level of HDL cholesterol was significantly higher after autogenic training (1.21 +/- 0.11 vs. 1.36 +/- 1.42) (p < 0.005). Cholesterol level was significantly lower after training (6.63 +/- 1.66 mmol/l vs. 6.10 +/- 1.12 mmol/l) (p < 0.05). Lipid peroxidase was significantly lower after treatment (4.05 +/- 0.58 vs. 3.69 +/- 1.26) (p < 0.005).

CONCLUSION

Autogenic training in selected patients, especially those who are most responsive to stress would provide benefits for glucosE control and lipid metabolism that are not always achieved by conventional treatment.

[Effect of hyperlipoproteinemia on blood fibrinolytic activity and thrombocyte aggregation]

BACKGROUND AND AIM

An impaired lipid metabolism and macrovascular disease are often associated with diabetes mellitus. Effects of hyperlipoproteinemia on fibrinolytic blood activity and platelet aggregation were investigated in noninsulin-dependent diabetes mellitus.

MATERIAL AND METHODS

The study sample consisted of 50 patients with noninsulin-dependent diabetes mellitus, only on dietetic regime. The following was studied: lipids (total cholesterol, HDL cholesterol and total triglycerides) fibrinolytic blood activity and platelet aggregation in patients with increased levels of cholesterol and triglycerides. We used enzymatic methods for lipids, Buckell's method for fibrinolysis (> 180 min) and Crean's method for platelet aggregation (6-8 s).

RESULTS

Statistical analysis of the obtained results shows significant changes in lipids. Triglycerides were significantly higher in diabetics with poor control (p < 0.01). Total cholesterol was significantly higher in patients with coronary disease, hypertension and diabetics with occlusive disease of low extremities (p < 0.01). HDL cholesterol was significantly lower in diabetics with coronary heart disease (p < 0.05). Statistical analysis showed significant changes in blood coagulability. Decreased fibrinolytic blood activity (158.10 + 31.3 min v.s. 169.82 + 21.05 min) (p < 0.05), as well as faster platelet aggregation (6.7 + 0.48 sec v.s. 6.8 + 0.93 sec) (p < 0.1) in patients with hypertriglyceridemia compared with the diabetics with normal triglycerides. Other lipids did not influence significantly the fibrinolysis and platelet aggregation in noninsulin-dependent diabetics.

CONCLUSION

All of this indicates the importance of the studied factors in the onset of atherosclerosis with patients with noninsulin-dependent diabetes; the latter is relevant to the importance of planned diabetic regime and moderate physical activity in preventing vascular complications of diabetes.

[Sodium excretion in children with lithogenic disorders]

INTRODUCTION

The causes of nephrolithisis are multifactorial and have not yet been enough investigated [1]. Hypercalciuria is the most common cause of metabolic nephrolithiasis [2-4]. Close relationship between urinary calcium and urinary sodium has been a subject of reported observations in the past, showing that high urinary sodium is associated with high urinary calcium [5-7]. Hyperoxaluria, hyperuricosuria and cystinuria are also metabolic disorders that can lead to nephrolithiasis. Recent studies have indicated that urinary elimination of cystine is influenced by urinary sodium excretion. Based on these observations it has been hypothesised that patients with high urinary sodium excretion are at high risk of urinary stone disease. The purpose of the study was to investigate sodium excretion in a 24-hour urine and first morning urine collected from children with lithogenic metabolic abnormalities (hypercalciuria, hyperoxaluria, hyperuricosuria, cystinuria), both with nephrolithiasis and without it, in order to determine its significance in urinary calculi formation.

PATIENTS AND METHODS

Urinary sodium excretion was investigated in 2 groups of children: patients with lithogenic metabolic abnormalities, but without urinary stone disease (L group) and patients with nephrolithiasis (C group). Both groups were divided into 2 subgroups: patients with hypercalciuria and without it. There were 22 patients in group L (mean age 11.97 +/- 4.13 years), of whom 17 formed a hypercalciuric subgroup and 5 formed a non-hypercalciuric subgroup (3 patients with hyperuricosuria and 2 patients with hyperoxaluria). Group C consisted of 21 patients with nephrolithiasis (mean age 12.67 +/- 3.44 years), of whom 6 formed a hypercalciuric subgroup and 15 formed a non-hypercalciuric group (2 patients with cystinuria and 13 patients without lithogenic metabolic abnormalities). Control group consisted of 42 healthy age-matched children. All subjects had a normal renal function. A detailed history and clinical examination were done, and ultrasonography was performed in all patients. A 24-hour urine, first morning urine and serum specimen were analysed for sodium, potassium, calcium, uric acid, urea and creatinine. Fractional excretion of sodium, as well as urinary sodium to creatinin ratio and urinary sodium to potassium ratio, were calculated from the findings. Sodium and potassium levels were determined by flame photometry, calcium was measured by atomic absorption technique (Beckman Atomic Spectrophotometer, Synchron CX-5 model, USA), uric acid by carbonate method and creatinine by Jaffe technique. Cystine and dibasic amino acids were quantified by ion chromatography. Urinary oxalate excretion was determined by enzyme spectrophotometry. Hypercalciuria was defined by 24-hour calcium excretion greater than 3.5 mg/kg per day and/or calcium to creatinine ratio greater than 0.20 [8]. Uric acid excretion was expressed as uric acid excretion factored for glomerular filtration, according to Stapleton's and Nash's formula [9]. Normal values were lower than 0.57 mg/dl of glomerular filtration rate in 24-hour samples. Mean values were statistically analyzed by Pearson's linear correlation and analysis of variance (ANOVA).

RESULTS

Urinary sodium concentration values including urinary sodium to potassium ratios, are shown in Table 1. We found that urinary sodium excretion was significantly increased in patients of both L and C groups when compared with controls (p < 0.05). Further analysis of the subgroups showed that urinary sodium excretion was significantly higher only in patients with hypercalciuria of both L and C groups in comparison to controls (p < 0.05) (Table 2). A significant positive correlation was found between 24-hour urinary sodium to creatinine ratio and urinary calcium to creatinine ratio (r = 0.31; p < 0.001) (Graph 1), as well as between urinary sodium to potassium ratio in 24-hour and first morning urine (r = 0.69; p < 0.001) (Graph 2). (A

[Circadian rhythm of blood pressure and daily hormonal variations]

As the mortality rate due to cardiovascular complications has increased, knowing the importance of the diurnal cycle of blood pressure, ambulatory blood pressure was recorded in 50 noninsulin-dependent diabetics aged 45 to 65 years. The diurnal cycle of the serum levels of cortisol, prolactin and growth hormone were determined by RIA (radioimmunoassay) method and urinary catechlamines by radioenzymatic method. The obtained results showed significantly higher blood pressure values during sleeping periods in patients with severe hypertension and consequently significantly lower night/day ratio of cortisol and urinary catecholamines as well as increased prolactin. In diabetic patients with autonomic neuropathy blood pressure values were significantly higher during night, but without changes in regard to hormones. It can be concluded that glucocorticoid hormones and catecholamines might be associated with the control of diurnal cycle of blood pressure in patients with severe hypertension.

[Functional, organic and histologic changes in the stomach in diabetic patients in relation to the presence of diabetic neuropathy]

Functional, organic and histological gastric changes were investigated in relation to the presence of autonomic neuropathy in 105 noninsulin-dependent diabetics (20 with autonomic neuropathy, 35 with peripheral neuropathy, 30 with both peripheral and autonomic neuropathy and 20 without neuropathy) and 40 control persons. The diagnosis of autonomic neuropathy was assessed by parasympathetic test of cardiovascular reflexes and peripheral neuropathy by classical neurological examination and EMG (Electromyogram). All subjects were examined by radiologic and endoscopic methods with gastric biopsy specimens for histologic and immunocytochemical analysis. The results of investigation showed that functional abnormalities, hiatus hernia (55%) and pylorospasm (50%) occur more frequently in patients with autonomic neuropathy. Gastritis, duodenal ulcer (5%) and polyps (25%) are significantly more frequent. Atrophic gastritis type A (20%) was more frequent in diabetics with autonomic neuropathy than in other diabetics, as well as other types of gastritis. Immunocytochemical analysis showed the presence of rare, pale ECL (Extensor Caudae Lateralis) cells in corpus and pale, hypogranulated G cells in antrum and hyperplasia and metaplasia of EC (Embryonal carcinoma) cells in antrum of the stomach. Functional, organic and histologic changes in patients with diabetic autonomic neuropathy suggest that the systemic investigation of the Gut is very important in such patients.

[Biochemistry in liver cancer]

In a group of patients (n=18) with primary (n=7) liver cancer high increase in enzyme activities (AST, ALT, AP, gama-GT, 5'NU), billirubin, alpha-1 AT, alpha- and beta-globulins and alpha-phetoprotein, and considerable decrease of albumin and cholinesterase, were established. These disturbances were duo to the weakened biofunction of the liver. All the examined biochemical parameters are of great significance in the differential diagnosis of cancer, prognosis and development of the disease.

[The change concentrations in the serum of immunoglobulins and alpha-1 atitrypsin in children with obstructive pulmonary diseases]

Total concentrations of IgA, IgM, IgG, IgE and alpha-antitypsin were determined in the sera of 50 children of different age with bronchial asthma and obstructive bronchitis and 20 healthy children as control group. By using radial immunodifusion method the total IgA, IgM, IgG and alpha-antitrypsin were determined. Significantly higher values of IgE (t=5.17; p<0.01) and alpha-1 antitrypsin (t=4.6; p<0.01) were found in group of seek children. No significant difference in concentrations of IgA, IgM and IgG. Higher values of IgE and alpha-antitrypsin suggesting their pathophysiologic significance in airway obstruction infection in children with chronic obstructive pulmonary diseases.

[Dynamic scintigraphy of gastric emptying in non-insulin dependent diabetics with autonomic neuropathy]

To ascertain whether gastric emptying of solids is affected by visceral autonomic neuropathy, 30 noninsulin-dependent diabetics (10 with autonomic neuropathy, 10 with peripheral and 10 without neuropathy) and 10 control subjects were studied. Subjects were screened by clonidine test and two parasympathetic tests of cardiovascular reflexes to identify the presence of autonomic neuropathy. The peripheral neuropathy was diagnosed by classic neurological examination and EMG. Delayed gastric emptying was assessed by dynamic scintigraphy, using 99mTc labeled ham and eggs. The gastric emptying of solids was markedly delayed in diabetics, particularly in diabetics with poor metabolic control (p < 0.01) and those with autonomic and peripheral diabetic neuropathy (p < 0.05). The results of our study suggest that dynamic scintigraphy may be a more sensitive method than other tests for autonomic dysfunction of the gut in diabetics with the early manifestation of diabetic gastroparesis.

[Response of pancreatic polypeptide to a protein rich meal in insulin non dependent diabetes melitus and autonomic neuropathy]

Parasympathetic function and plasma hPP response to a protein rich meal were evaluated in 105 insulin non-dependent diabetic patients: 20 with autonomic neuropathy (group A), diagnosed by Clonidin test; 35 patients with neurophysiological evidence of polyneuropath (group B); 30 patients with autonomic neuropathy and polineuropathy (group C), and 20 patients without any sign of neuropathy (group D). Plasma hPP levels were determined by RIA using an anti-hPP antiserum, kindly provided by Prof. S. R. Bloom (Hammersmith Hospital, London). Blood was taken at 0. 45 and 60 minutes after the beginning of the meal. In groups A and C, the meal induced hPP increase was significantly lower than in group D (p 0.001). All group B patients had a marked increase in the peptide, similar to that in diabetics without neuropathy. These result ssuggest that diabetic autonomic neuropathy is associated with dysfunction of hPP secretion, and that the evaluation of hPP response to test meal may be a sensitive and simple method for the assessment of paraympathetic impairment in diabetes.

[Diagnostic value of the NBT-PABA test in the functional evaluation of the exocrine pancreas]

N benzoyl-L-tyrosil PABA was orally administered to 13 controls and 35 patients with pancreatic disease: 7 with chronic exocrine pancreatic disease, 7 patients after an attack of acute pancreatitis, 3 with carcinoma of the pancreas, 8 with biliary tract disease and 10 with diabetes. The amount of PABA excreted serves as parameter exocrine pancreatic function. PABA excretion in patients with chronic pancreatitis (p < 0.01) and diabetes (p < 0.05) was significantly less then in controls. The present data justify further investigation of this procedure as a possible new oral test of exocrine pancreatic function.

[Serum gastrin in patients with diabetes]

We evaluated the basal and postprandial circulating levels of gastrin in 20 diabetic patients and in 20 normal subject. The basal gastrin concentrations were not statistically different in comparison to controls. The blood tests provoked increased circulating levels of gastrin. In our study diabetes significantly enhanced that response, particularly in diabetics with severe disease, peripheral neuropathy and in untreated patients. Histologic evidence of antral hyperplasia was obtained in 7 patients; atrophic gastritis and intestinal metaplasia were found in 3 diabetics. We postulate that postprandial gastrin levels raised secondary to achlorhydria, common in diabetics.

[Serum antithyroid antibodies in patients with pernicious anemia]

We investigated the incidence of thyroid auto-antibodies and their relationship to antigastric antibodies in 20 euthyroid patients with pernicious anaemia. To evaluate possible thyroid dysfunction we also measured total level of thyroid hormones (TT3 and TT4) and TSH in our patients. Histologic evidence of autoimmune atrophic gastritis and intestinal metaplasia was obtained in 15 patients. We found that it was surprisingly high incidence of thyroid auto-antibodies in patients with pernicious anaemia, particularly in the group with intestinal metaplasia (antithyreoglobulin antibodies 71% and antimicrosomal antibodies 100%). The incidence of antigastric antibodies in these patients was similar to that of those with significant antithyroid antibodies (16/18). Total triiodo thyronine and TSH were significantly higher in the patients with pernicious anaemia than in the control group (p less than 0.05), in the normal range. The results of our study suggest that this upset in immunological physiology is due to a more generalized defect in immune tolerance.

[Apolipoprotein A in patients with alcoholic liver disease]

The aim of the present study was to determine the apolipoprotein A (APO-A) an the high density lipoprotein (HDL) plasma concentrations in 25 patients with alcoholic liver cirrhosis. To evaluate the severity of liver disease serum albumin, bilirubin and total bile acids were measured. The serum level of APO-A and HDL was significantly lower in patients with alcoholic liver cirrhosis than in normal controls (p < 0.01) and markedly lower in patients with advanced liver cirrhosis. Apolipoprotein A concentrations in plasma correlated positively with serum albumin (p < 0.01) and negatively with serum bilirubin (p < 0.01) and bile acids (p < 0.01). Thus, he apoliprotein A level seems to reflect the severity of liver disease.

[Lipids and total bile acids in the blood of patients with inflammatory bowel diseases]

We evaluated the total plasma bile acids, total lipids, total cholesterol, total triglicerides, LDL-cholesterol, HDL-cholesterol, phospholipids and lipoproteins (APOA-A and APO-B) in 25 patients with inflammatory bowel disease: 20 with ulcerative colitis (UC) and 5 with Crohn's disease. In comparison to 17 healthy volunteers, the total plasma bile acids were decreased in all patients. The serum level of total cholesterol, LDL-Ch, HDL-ch and APO-A was significantly lower in patients with Crohn's disease and ulcerative colitis (p less than 0.01) than in normal controls; total triglycerides and APO-B were decreased only in the group with Crohn's disease (p less than 0.05). Thus, decreased values of total plasma bile acids malabsorption, and they suggest a more important romalabsortion, and they suggest a more important role of the colon in the preservation of bile acids.

[Hormone levels in patients with alcoholic liver cirrhosis]

The purpose of the study was to evaluate some of the hormones in 20 patients with alcoholic cirrhosis. We investigated the diurnal rhythmicity of some of the hormones (cortisol, follicle-stimulating hormone-FSH, luteinizing hormone-LH, growth hormone-LH, prolactin-PRL) and basal serum concentrations of thyroid-stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4) and testosterone, as well as gastrin and insulin, using provocative tests. Statistical analysis of the results obtained from the observed patients compared with controls, showed significantly lower concentrations of T3 (p less than 0.05), cortisol (p less than 0.05), testosterone (p less than 0.05) and FSH (p less than 0.05), and significantly higher (p less than 0.01) serum concentration of prolactin. Then, in the cirrhotic group the serum concentrations of gastrin and insulin increased significantly (p less than 0.01), together with the disorders of carbohydrate metabolism (impaired glucose tolerance and diabetes mellitus. The described disturbances of some of the observed hormones are complex, particularly in their relationship by which the clinical picture of the cirrhotic patients can be explained.

[Serum cholesterol and triglycerides in patients with benign and malignant tumors of the colon and rectum]

There are many epidemiological papers on the relation of lipids especially of cholesterol, and the incidence of colorectal adenoma and cancer. In the studies of pathogenesis of the cancer of the large intestine attention is paid to the role of certain lipoproteins of bile acids and certain gastrointestinal hormones. We examined 30 patients: 10 were healthy subjects (the control group), 9 with colorectal adenoma, 2 with villous adenoma and 9 with adenocarcinoma of the colon and the rectum. The study concerned: total lipids, total cholesterol, total triglycerides, LDL cholesterol, HDL cholesterol, phospholipids, gastrinaemia and insulinaemia. Statistical analysis of the obtained results showed that hypocholesterolemia followed the incidence of adenocarcinoma. This is in accordance with the most frequently quoted literature. The incidence of hypergastrinaemia, however, was found primarily in the patients with villous adenoma, which indicates possible secretory function of the studied tumours.