Cathepsin D: association between TN-stage and steroid receptor status of breast carcinoma

PURPOSE

To assess whether the expression of estrogen-induced protease, cathepsin D, might facilitate biological subgrouping of patients with breast carcinomas, and accordingly, its potential applicability in clinical oncology.

PATIENTS AND METHODS

This study includes 70 patients with histologically confirmed breast carcinoma. Pathological findings were classified according to tumor size (T) and the presence or absence of metastases in regional lymph nodes (N). Steroid hormone receptor (SR) density as well as cathepsin D concentrations were assayed in the cytosol of breast carcinomas in accordance with the recommendation of the EORTC.

RESULTS AND DISCUSSION

Statistically significant direct correlations were observed between cathepsin D expression and axillary node status as well as SR status. However, it is important to point out that in spite of these statistically significant findings, there were no biologically significant associations due to a wide range of individual cathepsin D values. Baseline levels of cathepsin D expression were found in patients with SR-negative status and node-negative tumors as well as in patients with SR-negative status and tumors of </=2 cm. Accordingly, a clinical significance of cathepsin D expression may be assumed.

[The captopril test--an aid in the detection of scarring nephropathy as a cause of arterial hypertension in children]

Renal scarring with and without vesicoureteral reflux (VUR) has been now recognized as an important cause of paediatric hypertension for many years [1-5]. However, its pathogenesis has still remained uncleared. The widespread concept implicated the activation of renin-angiotensin system finding a powerfull support in higher peripheral plasma renin activity (PRA) in children with reflux nephropathy than in controls [6, 7] and in beneficial antihypertensive effects of ACE inhibitors. The latter, in form of captopril, has also been used in captopril test and in renal scintigraphy and isotope renography following the administration of captopril to provide evidence for renin dependent hypertension [8, 9]. Published studies of captopril test have centred on the identification of renovascular as opposed to essential hypertension [10-18, 20-22]. The aim of our study was to assess the usefulness of captopril test in differentiation between hypertensive children with renal scarring from those with essential hypertension. We studied blood pressure (BP) and PRA responses to a single dose of captopril in two groups of hypertensive children. Group A consisted of 29 patients, 14 boys and 15 girls, who had renal scaring as demonstrated by renal 99mTc dimercaptosuccinid acid scan (99m Tc DMSA) and/or intravenous pyelography. Group B included 19 patients, 19 boys and 10 girls who had arterial hypertension, while clinical examination excluded renal and other definable causes of BP elevation, and they were therefore considered to have essential hypertension. At the time of the study all patients had normal glomerular filtration rate and were not salt depleted. They did not receive any antihypertensive medication for at least two weeks. The test was performed in the morning in fasting sitting patients. At the start of the test a small vein in the hand or forearm was cannulated to permit blood sampling. BP was measured 10, 20, and 30 minutes before captopril administration to get baseline BP (mean of these three measurements) and to allow the children to become accustomed to the test procedure. A single oral dose of captopril 0.64 +/- 0.04 mg/kg body weight was given to patients from group A and almost the same dose of captopril, 0.63 +/- 0.05 mg/kg body weight, to patients from group B. The patients remained sitting and BP was measured every 15 minutes during an hour. Blood for PRA was drown in the sitting position (17 patients from group A and 16 patients from group B) before and one hour after the dose of captopril. Samples of blood for basal PRA were collected from 16 patients from group A and in 14 patients from in B in lying position after waking up in the morning. PRA was measured by radioimmunoassay using a commercially available kit, SB-REN 2, from CIS Bio International. According to the criteria of Muller et al. [10] the captopril test was positive if the post-captopril PRA (ng/ml/h) was greater than or equal to 12 with an increase of greater than or equal to 10 and relative increase of greater than or equal to 15% (400% if initial PRA was < 3). The results of our study are presented in Tables 1 and 2 and in Graphs 1 and 2. The age of patients, doses of captopril, initial BP and PRA before the use of captopril did not much differ between studied groups. Fall of BP and PRA increase were highly significant (p < 0.001) both in group A and group B. However, the hypotensive reaction of diastolic BP and MAP were more pronounced in group A (14.45 +/- 1.67% and 15.81 +/- 1.62%) than in group B (6.95 +/- 2.21% and 8.96 +/- 1.75%; p < 0.01), but there were no significant differences in PRA and systolic BP changes and positive results of captopril test between the studied groups. Hypotensive responses of diastolic BP and MAP greater than 10% of initial values were found to be more frequent in group A (79.32% and 79.31%) than in group B (26.61% and 31.57 degrees %; p < 0.001 and p < 0.01). Diastolic BP and MAP were directly related to the dose of cap

L-arginine reduces tubular cell injury in acute post-ischaemic renal failure

BACKGROUND

The pathophysiology of renal ischaemia, resulting in tubular cell injury and leading to acute renal failure (ARF), remains unclear. An ever-increasing number of investigations focus on a possible role of nitric oxide (NO) in regulating circulation during ARF. In this context, we investigated the influence of chronic stimulation or inhibition of NO synthesis, or both, on haemodynamic parameters, histology and plasma renin activity (PRA) after ischaemia-reperfusion injury of rat kidneys.

METHODS

Experiments were performed on adult, male Wistar rats. Before induction of ARF, a group of animals was treated with a NO synthesis inhibitor (L-NAME) and another group was treated with a precursor of NO synthesis (L-arginine). The animals received those substances for 4 weeks. Control groups received the same amount of tap water for 4 or 8 weeks and were divided into groups with ARF (4 weeks--ARF group and 8 weeks ARF group) and a sham-operated group. Another group of rats was treated first with L-NAME and then with L-arginine in their drinking water, for 4 weeks for each of these two substances. All parameters were evaluated 24 h after the induction of ischaemic ARF or the sham operation.

RESULTS

Our results show that such long-term stimulation of NO release by L-arginine improved renal haemodynamics in the ischaemic form of ARF. Renal blood flow (RBF) increased by 96% in the L-arginine-treated rats with ARF compared with the group with ARF alone. Inhibition of NO synthesis worsens renal haemodynamics after ARF. However, this aggravation can be reversed by L-arginine. The rate of water reabsorption was reduced in all groups with ARF, but this reduction was least in the group treated with L-arginine. The rate of Na+ reabsorption was reduced in all groups 24 h after renal ischaemia, but a significant decrease was observed after the inhibition of NO synthesis. Histological examination of the kidney specimens showed that morphological changes were least in the rats treated with L-arginine, when compared with all other groups with ARF. Nevertheless, the lesions were most prominent in the L-NAME+ARF group. In this group, the areas of corticomedullar necrosis were more widespread in comparison with other groups, especially the L-arginine group where only swelling of the proximal tubular cells was observed. Treatment with L-NAME was not accompanied by any significant alteration in the plasma concentration of angiotensin I (ANG I), while in the group treated with L-arginine ANG I had a tendency to decrease.

CONCLUSIONS

Acute post-ischaemic renal failure may be alleviated by administering the NO substrate (L-arginine). NO acts cytoprotectively on tubular epithelial cells in ischaemia--reperfusion injury of rat kidney. Evidence of this comes from both histopathological findings and increased tubular water and sodium reabsorption. However, inhibition of NO synthesis (provoked by L-NAME) worsens renal haemodynamics and aggravates morphological changes after ARF. These aggravations can, however, be reversed by L-arginine.

[Serum osteocalcin in children with chronic renal insufficiency]

The research of the bone metabolism has undergone a long evolution which began with the use of radioisotopes in calcium kinetic studies and went through the determination of several humoral parameters like alkaline phosphatase (ALP), hydroxyproline and intact immunoreactive parathyroid hormone (iPTH) and finally to the assay of a new serum and urinary parameters of bone metabolism, like osteocalcine (OC) and procollagen and collagen metabolites. The X-ray study of the skeleton, densitometric techniques, computerized tomography, scintigraphy and NMR are used for visualization of bone changes, but bone biopsy and histomorphometry provide the most precise evaluation [1]. Disorders of bone and mineral metabolism in children with chronic renal failure (CRF) are an almost regular occurrence; so early discovery and treatment of these changes are very important [2]. The aim of this study was to measure the serum OC level in children with CRF and terminal renal failure (TRF), treated with chronic haemodialysis, and to evaluate the significance of OC compared to other humoral parameters of renal osteodistrophy, such as ALP and iPTH.

MATERIALS AND METHODS

We studied the fasting levels of OC in three different groups of children: group A consisted of 18 patients with TRF; group B consisted of 12 patients at different stages of CRF, and group C consisted of 32 healthy children, all of the approximately same age. Clinical characteristics of the examinded children are presented in Table 1. Of 30 patients, 26 were treated with calcium carbonate and 21 with vitamin D analogues. None were treated with aluminium hydroxide. Additional parameters included serum calcium, phosphate, ALP and body height, while serum concentrations of iPTH and ionized serum calcium were measured only in group A. Serum OC was measured by radioimmunoassay using OSTK PR RIA (CIS), while ELISA-PTH (CIS) radioimmunoassay was used to determine iPTH plasma levels. Statistical analyses were performed using Kolmogorov-Smirnov test to confirm normal distribution, the Pearson and Spearman rank sum test for correlation between variables of interest, while analysis of variance was used to compare the findings.

RESULTS

Serum OC levels were significantly different in all groups (p < 0.01); they were three times higher in group A than in group C. Similar increase was noticed in plasma iPTH, assuming that "normal" uremic iPTH was raised up to threefold above normal range (between 10 and 60 pg/ml) [2]. However, the total serum ALP activity was not sensitive as OC and iPTH, since ALP increases were less as compared to them. OC was age related only in group A (p < 0.01), with a positive correlation between OC and duration of haemodialysis (p < 0.05), as well as between OC and serum phosphate (p < 0.05), but there was no correlation between OC and growth retardation (expressed by SDS), bone age and current therapy for renal osteodistrophy. A direct correlation between OC and ALP was found only in healthy children (p < 0.01), while in groups A and B it was remarkable, although not statistically significant (p = 0.08) (Graphs 1, 2, 3). In group A, ALP and iPTH were directly correlated (p < 0.001), but the correlation of OC with iPTH was less significant (p = 0.06). In patients with CRF no correlation was found between glomerular filtration rate and OC.

DISCUSSION

OC is a bone-derived noncollagenous protein of low molecular weight (about 5800 D), containing residues of the vitamin K dependent amino acid gamma-carboxyglutamic acid and is synthesized by osteoblasts and odontoblasts. Calcitriol is a potent stimulator of OC synthesis, acting at the transcriptional level and increasing mRNA severalfold. OC is found mainly in bone, but nanomolar concentrations circulate in the blood. Its serum levels are an expression of the bone formation process and are age related (higher in the neonatal and adolescent period). ABSTRACT TRUNCATED.

Endothelin-1 in acute renal failure

To study the pathological significance of circulating endothelin (ET) in ARF, we measured plasma ET in seven children (mean age 8.8 +/- 4.4 years) with ARF in the most severe phase and 3.7 +/- 3.5 months later in the recovery period. Twenty-seven healthy children were included in the study as controls. Plasma ET level was measured by highly sensitive and specific radioimmunoassay for ET-1 and ET-2 (ET-1/2, Biomedica, Vienna). Plasma ET was significantly higher in the most severe phase of ARF (4.75 +/- 4.08 fM/ml) than in the recovery period (0.78 +/- 0.24 fM/ml; p < 0.01), but comparing to plasma ET in the healthy children, the difference was only of borderline statistical significance (Pf, 0.0573). Since plasma concentrations of creatinine did not correlate with plasma ET in patients, either in acute or in the recovery phase of disease, we concluded that decreased GFR is not the main factor determining an increased ET in ARF. We suggest that elevated plasma ET in ARF may be secondary to vascular endothelial dysfunction and speculate that enhancement synthesis of endothelial relaxing factor (EDRF) inhibits ET synthesis during the recovery period. We did not find any relationship between plasma ET and blood pressure (BP) in patients with ARF, so we conclude that circulating ET is not the main factor determining BP in ARF.

[The effect of hemodialysis on endothelin-1 plasma levels in children with terminal renal insufficiency]

We analysed the effect of hemodialysis (HD) on endothelin (ET) plasma level in children with terminal renal failure. Twenty-five patients (pts) and 27 healthy children as controls were included in the study. There was no difference in ET plasma levels in pts before HD (1.97 +/- 1.45) and controls (2.08 +/- 1.47), but ET increased in plasma of pts after HD (4.10 +/- 3.66). To estimate the relationship of volume depletion or depuration on ET plasma level changes in pts during HD, ET was measured at three time points of HD (before ultrafiltration-UF, after UF, and after HD without fluid removal) in 10 pts. ET level was not significantly changed after UF (1.93 +/- 2.25 vs 1.71 +/- 1.50; ns), but was significantly increased after depuration (4.46 +/- 3.56; p < 0.05). There was no correlation between ET and blood pressure in controls and pts in either period of testing, neither with plasma renin activity, left ventricular mass index, and body weight changes during HD.

[Significance of endothelin in arterial hypertension in children]

Concentration of plasma endothelin and the activity of Na(+)-K(+)-ATP-ase were determined in 3 different groups of children: the 1st group comprised 13 children with essential hypertension, aged 12.9+/-4.8; the 2nd group concerned 16 children with renal hypertension, but with preserved global renal function, aged 13.7+/-2.8, and the 3rd group consisted of 27 healthy children, aged 11.6+/-6.3 years. Plasma endothelin concentrations were measured by radioimmunological method, using a set manufactured by "Biomedica". The activity of Na(+)-K(+)-ATPase was determined in erythrocyte haemolysate by measuring the quantity of released inorganic phosphate in samples with and without ouabaine. Concentration of plasma endothelin was not significantly different between the children with arterial hypertension and healthy children, and there was no significant correlation between endothelin concentration and blood pressure in either of the 3 groups of children. The activity of Na(+)-K(+)-ATP-ase was significantly decreased only in the 1st group of children. There was no evidence of correlation between the Na(+)-K(+)-ATPase activity and blood pressure or plasma endothelin either in healthy, or in hypertensive children.

CONCLUSION

Endothelin in blood circulation has no significance in regulating blood pressure in healthy children. It also has no direct role on the development of essential and renal hypertension in children. The activity of Na(+)-K(+)-ATP-ase is decreased in children with essential hypertension, but it seems that it has no direct impact on hypertension. Endothelin in circulation and Na(+)-K(+)-ATP-ase activity are not interdependant.

Labelling of leukocytes with 99mTc-HMPAO for scintigraphy of inflammatory lesions and abscesses

A simplified and efficient procedure for 99mTc-HMPAO-labelling of leukocytes is described. For this purpose, the pH and concentration of the 99mTc-HMPAO preparation was modified. Leukocytes were isolated from a 20 mL mixture of patient blood, 5 mL ACD and 0.8 mL methylcellulose after 1 h sedimentation of erythrocytes and centrifugation (at 400 g) of the obtained plasma layer. Simultaneously, 99mTc-HMPAO was prepared (one single-dose kit for two patients) by adding 2.2 mL 99mTc-generator eluate and, after 10 min, 0.3 mL of phosphate buffer to lower the pH to 7. The isolated WBCs were then labelled by the addition of 1-1.2 mL of 99mTc-HMPAO solution and incubated for 20 min. The unbound tracer was then discarded, the labelled WBC washed and finally resuspended in autologous cell-free plasma. Leukocytes labelled by this procedure were used for scintigraphic localization of inflammatory lesions and abscesses in the gastro-intestinal tract. The labelling efficiency was 60 +/- 9%, with a separation yield of 55 +/- 11%.

[Proteinuria and beta 2-microglobulinuria in patients with tumors of the renal pelvis and ureter and in healthy persons from areas of endemic nephropathy]

Total proteinuria (SSA test) and beta-2-microglobulinuria (radial immunodiffusion and radioimmunoassay tests) were measured in 60 rural patients with histologically proven tumors of the renal pelvis and ureters and as many individually matched controls. The controls were the first neighbours of the same sex, age (+/- 2 yrs), profession and migratory history. Urinalysis was performed twice with an interval of nine years (in 1973/4 and 1982/3). As expected, both proteinuria and beta-2-microglobulinuria were more frequently elevated among the patients. However, these tests were very often positive among the controls as well. Thus, the prevalence rate of hyper-beta-2-microglobulinuria, as measured by the RIA method in 1982/3, was 26.3% in the control group. A high frequency of the tubular damage, as revealed by this test, among presumably healthy persons has been attributed to the fact that most upper urothelial tumor cases come from the Balkan endemic nephropathy foci where a significant proportion of inhabitants show signs of kidney affection.

[TSH receptor antibodies determined by the Thybia test in children with hyperthyroidism]

Using a radioreceptor assay Thybia-test, we studied 22 girls with Graves' disease, aged 4.0 to 20.4 years (mean = 13.8 years). Sera of 9 girls were obtained before therapy, 20 during treatment with methimazole, 4 in remission and 2 relapse. The total number of tested sera was 113. Control sera were obtained from 19 age-matched controls. The results of Thybia-test were positive in 7 of 9 girls with Graves' disease before treatment (77.8%) and in both girls in relapse. Of 89 samples of sera taken during drug therapy Thybia-test was positive in 51. Only 3 of 13 sera taken in remission gave positive results. The highest mean values of Thybia-test were detected in patients in relapse (46.2%), and in patients before therapy (23.9%). During treatment mean values became lower (14.4%) and were the lowest in remission of the disease (6.9%). The results of Thybia-test in controls ranged from 0% to 7.5% (mean = 1.93 +/- 2.78%). Significant differences were noticed between mean values of Thybia-test of patients before therapy and controls as well as between patients during therapy and controls. Six girls were studied after discontinuation of thyreosuppressive therapy. In 5 results of Thybia-test were negative. Three of them are still in long remission. Two were in short remission and relaps in both of them was followed by convertion of Thybia-test to positive. At the end of treatment the only patient with positive Thybia-test was in remission and Thybia-test was-later converted to negative. Our study shows that Thybia-test is a valuable method in addition to others used to correlate the natural history of the disease with the results of therapy. We are still unable to make a definite statement on the significance of this method in prediction of relapse and remission of Graves' disease.

Delayed-type allergy against various insulin preparations including human semisynthetic insulin

The authors present a patient with delayed-type allergy against insulin preparations of different species including highly purified monocomponent insulin and human semisynthetic insulin. Positive results for cutaneous delayed-type hypersensitivity and for lymphocyte blastogenesis suggested a type IV immunopathogenic reaction. Intradermal tests performed with various components of insulin preparations revealed delayed-type allergy to insulins of different species (bovine, porcine and human) but not to any of the other components.

[Endocrine and metabolic mechanisms of the pathological syndrome due to antigens of homologous glial tissue in monkeys]

Monkeys (Macaca mulatta) of both sexes repeatedly immunized with a complex of glial antigens of the homologous brain demonstrated abnormalities of hormonal functions after 1 to 5 weeks. These abnormalities were marked by a decrease in the total serum tyroxine (after 1 week) and a rise in the concentration of 11-hydroxycorticosteroids (11-OHCS) that occurred after 5 weeks. The changes in tyroxine level were more stable than those in the concentration of 11-OHCS. The immunized animals manifested changes in the disc electrophoregram of the serum. Application of stress resulted in a consistent elevation of the concentration of 11-OHCS and in temporary changes in the number and intensity of individual fractions of serum proteins. The fractional composition of serum proteins was different in control and experimental monkeys.