[Solitary distal femoral osteosarcoma in 89-year-old woman. Case report]. / Solitárny osteosarkóm distálneho femuru diagnostikovaný u 89-rocnej zeny.

The authors describe the case of an 89-year-old patient with a one-month history of pain in the right knee and a pathological fracture of the distal femur. Excisional biopsy showed a classical osteogenic sarcoma. The patient died after six months of palliative surgical and oncological therapy; her primary disease generalised and progressed with numerous metastases. The authors discuss the possibilities of histological diagnostics of osteogenic sarcoma and its differential diagnosis. They draw attention to a possible occurrence of this type of sarcoma also in elderly patients, and not only in adolescents.

Enhanced early after-myocardial infarction concentration of TNF-alpha subsequently increased circulating and myocardial adrenomedullin in spontaneously hypertensive rats.

Both inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) and the cardiac protective peptide adrenomedullin (AM) are increased in cardiac tissues and plasma in patients with myocardial infarction (MI) and chronic heart failure. Recently they have been increasingly recognized as important factors in the pathophysiology of MI and resultant congestive heart failure. Compared with sham-operated spontaneously hypertensive rats (SHR), we investigated myocardial immunoreactivity of TNF-alpha and AM and also their mutual relations in vivo in SHR+MI. Residual myocardial depression after MI was studied also in isolated perfused hearts. In chronic experiments, 24 and 48 h after permanent ligation of the descending anterior branch of the left coronary artery, we examined hemodynamics, plasma and myocardial peptide levels. Left ventricular function was assessed in isolated perfused hearts subjected to "global ischemia and reperfusion" and after induction of "calcium paradox". Circulating and myocardial TNF-alpha concentrations increased early after MI in SHR. Studies with global ischemia and calcium paradox in isolated heart showed early myocardial depression and calcium-dependent gradual increase of left-ventricular end-diastolic pressure. In the SHR+MI myocardial AM concentrations were increased 9- and 49-fold after respective 24 h and culminated 48 h following MI. Circulating and myocardial AM was increased in SHR+MI in association with TNFalpha-induced myocardial depression. The both studied cardiac parameters displayed the beneficial effect of the enhanced myocardial AM concentration.

The regulation of human adrenomedullin (AM) and tumor necrosis factor alpha (TNF-alpha) receptors on human epithelial carcinoma (HeLa) cells. The role of AM secretion in tumor cell sensitivity.

The cytostatic cytokine tumor necrosis factor-alpha (TNF-alpha) and proliferative hormone adrenomedullin (AM) are abundantly expressed in human tumors. However, little is known about mechanism (s) through which TNF-alpha and AM exert their regulatory effects, especially in the regulation of proliferative activity in malignant cells. Also the role played by TNF-alpha in pathogenesis and treatment of cancer (targeted cancer therapy) remains less understood. The purpose of this study was therefore to characterize the significance of TNF-alpha induced apoptosis with down-regulation of plasma-membrane TNF-alpha receptors and up-regulation of AM receptors with increased production of human AM mRNA, i.e. mechanisms that subsequently control aberrant cellular proliferation in malignant cells. Cytotoxicity, and the whole cell ligand binding assays for TNF-alpha and AM receptors, and RIA-assays of AM production were accomplished in control experiments using pharmacologically pretreated HeLa cells. AM increased proliferation of HeLa cells and AM antagonist (Ala6,21)AM(22-52) significantly antagonized this increase. TNF-alpha inhibitor of cell growth actinomycin-D significantly increased cytotoxicity of TNF-alpha in HeLa cells. Hypoxia increased TNF-alpha production and increased surface-membrane [125I]AM binding. Tumor promotor PMA and histamine down-regulated specific binding of [125I]TNF- alpha on HeLa cells. Mitogenic peptide endothelin-1 increased and specific ET-1 antagonist BQ123 and significantly reduced AM binding. Production of AM in HeLa cells markedly increased after exposure to hypoxia >ET-1 >PMA. BAY11-7082 at concentrations that inhibited IkappaB phosphorylation and thus nuclear translocation and surface membrane TNF-alpha expression increased AM specific binding. Pretreatment of cells inhibitor of HMGCoA reductase inhibitor VULM1457 significantly increased the total number of specific [125I]AM binding sites on HeLa cells. These results suggest relative and contradictory TNF-alpha and AM surface-membrane receptor signaling in HeLa cells and findings reveal a novel proliferative mechanisms that control AM production and thus oncogenic signaling in cells. This implies that several putative inhibitors of TNF-alpha and AM signaling may be considered in oncology for treatment of tumors otherwise nonresponding to cytostatic therapy.

Hypoxic stress-enhanced expression and release of adrenomedullin (AM) and up-regulated AM receptors, while glucose starvation reduced AM expression and release and down-regulated AM receptors in monkey renal cells.

The proliferative peptide adrenomedullin (AM) has a wide distribution in a variety of tissues and cells. The mechanism how the AM gene is regulated in cells is not yet known. The renal cortex, renal vascular smooth muscles, glomeruli and tubular epithelial cells are very sensitive to hypoxia. Renal hypoxia produces acute renal tubular necrosis and markedly induces AM expression in damaged cells. However, little information is available regarding the possible pathophysiological production and release of renal tubular AM. Regulation of membrane-bound AM receptors in renal cells has not yet been systematically studied. To elucidate the potential pathological role of human AM we examined the production and release of AM, as well as the characteristics of surface membrane AM receptors in cultured monkey renal tubular epithelial cells (RC) exposed to hypoxia, induced with endothelin-1, and subjected to glucose deprivation. Exposure of RC to hypoxia (1 % O(2), 5 % CO(2) in N(2)), and to phorbol 12-myristate 13-acetate (PMA) increased production and secretion of AM and increased specific [(125)I]AM binding on RC. Metabolic stress (1 % glucose in the cultivation medium) and preincubation of RC with rival peptide endothelin-1 significantly reduced immunoreactive-AM in a conditioned medium and whole cell surface membrane AM binding on RC. Altogether, our data suggest that the AM is involved in the adaptation of renal tubular cells to hypoxia. Increased expression of AM mRNA and regulation of AM receptors in metabolic stress may function as an important autocrine/paracrine regulator(s) of renal tubular epithelial cells.

The ACAT inhibitor VULM1457 significantly reduced production and secretion of adrenomedullin (AM) and down-regulated AM receptors on human hepatoblastic cells.

Acyl-CoA:cholesterol acyltransferase (ACAT) is an important enzyme in the pathways of cholesterol esterification. It has been shown that new ACAT inhibitor 1-(2,6-diisopropyl-phenyl)-3-[4-(4'-nitrophenylthio)phenyl] urea (VULM1457) significantly reduced atherogenic activity in animal experimental atherosclerosis. Proliferative hormone adrenomedullin (AM) has been shown to be released in response to hypoxia, however, its role in cellular protection has remained elusive. The effect of increased local production of AM in cells and resultant down-regulation of AM receptors has not been investigated yet. We hypothesized that increased expression of AM in hypoxic cells was the result of excessive AM production with resultant AM receptor down-regulation, surface-membrane protein degradation and that the new specific ACAT inhibitor would reduce AM induction in hypoxia and thus proliferation of cells. In order to investigate specific cellular AM signaling and protection induced by VULM1457, we characterized specific surface-membrane [125I]AM receptors expressed on cells, evaluated AM secretion (RIA assays), AM mRNA expression in cultured cells (RT-PCR analysis) and proliferation (incorporation of [3H]thymidine) in control, hypoxic and metabolically stressed human hepatoblastoma cell lines exposed to gradually increasing concentrations of VULM1457. The new ACAT inhibitor VULM1457 in concentration 0.03 and 0.1 micromol/l significantly down-regulated specific AM receptors on HepG2 cells, reduced AM secretion of HepG2 cells exposed to hypoxia. These results suggest that VULM1457, as new member of ACAT family of inhibitors could negatively regulate cell proliferation induced by AM, which may correlate with down-regulation of membrane-bound AM receptors on HepG2 cells, and moreover, with the induction and expression of AM in hypoxia.

In vitro cytotoxicity of berberine against HeLa and L1210 cancer cell lines.

Previous studies on anti-cancer activity of protoberberine alkaloids against a variety of cancer cell lines were extended to human uterus HeLa nad murine leukemia L1210 cell lines. Cytotoxicity was measured using in vitro techniques and cell morphology changes were examined by light microscopy in both cytostatic and cytocidal concentration ranges. The IC50 was found to be less than 4 microg/ml, a limit put forward by NCI for classification of the compound as a potential anti-cancer drug. The microscopy examination indicated that at cytocidal concentrations the HeLa and L120 cells died apoptotically. The comparative analysis revealed that berberine belongs to the camptothecin family of drugs characterized by the ability to induce DNA topoisomerase poisoning and hence apoptotic cell death. Although the cytotoxic potency of berberine was found to be several orders of magnitude lower compared to camptothecin, its significance may increase in future in view of the lack of unwanted side effects characteristic for camptothecin compounds currently in clinical use for treatment of cancer.

Plasma-levels of endothelin-1 and angiotensin-II and reactivity of arterial blood pressure to exogenous sympathomimetics and vasoactive peptides in rat model of malignant renal hypertension.

BACKGROUND: There is still considerable uncertainty regarding sensitivity of arterial blood pressure to endogenous peptides in renal hypertension. Many pathological processes including hypertension have been shown to be associated with release of endothelin-1 (ET-1). However the role of ET-1 in regulation of arterial blood pressure in hypertension is still controversial. OBJECTIVES: The role of endothelin-1 (ET-1) and angiotensin-II (AT-II) in malignant phase of renovascular hypertension has been assessed on the basis of arterial blood pressure increase and ETA receptor density measurements in Glodblatt-hypertensive rats (RVH). RESULTS: The arterial blood pressure response to sympatomimetic amines, vasopressors, the plasma ET-1 and AT-II levels as well as renal subtype-ETA receptor density were significantly increased in RVH rats with malignant hypertension. The dominance of vasopressor ETA receptors in RVH rats suggest the contribution of endothelin peptides to malignant renovascular hypertension. (Tab. 1, Fig. 7, Ref. 25.)

Enhanced endothelin ET(B) receptor down-regulation in human tumor cells.

The characteristics of specific binding of human [125I]Tyr(13)-endothelin-(1-21), [125I]-Tyr(13)-Suc-[Glu(9),Ala(11, 15)]-endothelin-(8-21), ([125I]IRL-1620) and endothelin ET(A) receptor antagonist [125I]Tyr(3)-(N-[(hexahydro-1H-azepin-1-yl)carbonyl]-L-Leu]-1Me )-D-Trp ([125I]PD151242) (number of sites and their affinity) and proliferation responses to exogenous endothelin receptor agonists (endothelin-1 and the endothelin ET(B) receptor-selective, truncated N-acetyl-[Ala(11,15)]-endothelin-(6-21) analogue BQ3020) were determined in cultured human fibroblasts and in tumorigenic HeLa cells. The cells were pre-incubated with equimolar concentrations of human endothelin-1 or its truncated analogue BQ3020. After pre-incubation (2 h), both peptides induced down-regulation of surface-membrane endothelin-1 receptors. This process was specific for endothelin ET(B) receptors and was much more intensive in tumorigenic cells. BQ3020, acting mostly through its C-terminus, induced nearly maximal endothelin ET(B) receptor down-regulation in HeLa cells. Staurosporine, a wide spectrum protein kinase inhibitor, significantly reduced, and N-[N-[N-[2, 6-dimethyl-1piperidinyl)carbonyl]-4-Me-L-Leu]-1-(methoxycarbonyl)- D-t ryptophanyl]-D-norleucine (BQ788), an endothelin ET(B) receptor antagonist, attenuated the down-regulation of endothelin receptors induced by endothelin receptor agonists. The down-regulation of endothelin ET(B) receptors was prevented by pre-incubation of the cells with the lysosomal enzyme blocker chloroquine. The endothelin-1-induced cell proliferation was attenuated by pre-incubation of the cells with the non-selective endothelin receptor antagonist Ac-D-10,11-dihydro-5H-dibenzo[a,d] cycloheptene-glycine-3,3-D-diphenyl-Ala-Leu-Asp-Ile-Ile-Trp (PD142893) and it was only partially reduced by the endothelin ET(A) receptor-selective endothelin antagonist PD151242.

[Treatment of acromioclavicular dislocation after bosworth.]. / Liecba akromioklavikulárnej luxácie operáciou podla Boswortha.

The authors present a group of 60 acromioclavicular dislocations of Tossy III type in 59 patients whom they operated on in the period of 1992-1996. Within the use of a variety of methods of the surgery of acromioclavicular dislocation they achieved the best results by a timely suture of the coracoclavicular ligament and stabilization of the clavicula by a Bosworth screw. They have been using this method most frequently since 1990 as when performed in time and technically correctly it is very efficient despite its certain drawbacks. The authors emphasize mainly technical aspects of a timely acromioclavicular stabilization by a cancellous screw. In the conclusion they formulate principles of the use of the method of stabilization by a screw after Bosworth for the achievement of a good functional result. Key words: acromioclavicular dislocation, acromioclavicular stabilization by a screw after Bosworth.

Effect of the new beta-adrenolytic compound propyl-3-acetyl-4-[(2-hydroxy-3-isopropylamino) propoxy]carbanylate hydrochloride on isolated heart muscle.

The effect of the new beta-adrenolytic drug Bl 343 Ac (propyl-3-acetyl-4-[(2-hydroxy-3-isopropylamino) propoxy] carbanylate hydrochloride) was tested in preparations of the guinea-pig atrium and compared with the effects of propranolol and metipranolol. BL 343 Ac has an affinity to beta-adrenergic receptors, expressed as the pA2 value, which is comparable to those of propranolol and metipranolol. To achieve the slope of the Schild plot not different from unity, it was necessary to prolong incubation of the drug with the tissue to 75 min. At the concentrations of 10(-5) and 10(-4) mol/l and higher, BL 343 Ac was found to have negative chronotropic and inotropic effects, respectively. IN atria isolated from guinea-pigs and rats premedicated with reserpine, application of 10(-8) and 10(-7) mol/l of Bl 343 Ac exhibited a slightly stimulatory effect on the chronotropy. A positive inotropic effect of Bl 343 Ac was observed on the left guinea-pig atria after prolongation of the incubation time of the drug with the tissue up to 75 min. This inotropic effect of Bl 343 Ac may be associated with an increased concentration of cyclic adenosine monophosphate (cAMP), observed after 1-h incubation with the drug (from 0.78 +/- 0.05 to 1.13 +/- 0.09 pmol/mg w.w. cAMP). Bl 343 Ac, similarly to propranolol and metipranolol, prolonged the refractory period in the atrial preparations starting with the concentration of 10(-6) mol/l. In the ventricular preparations, Bl 343 Ac shortened the refractory period up to the concentration of 10(-5) mol/l, similarly to propranolol.

[The effect of diltiazem on atrioventricular conduction in dogs]. / Ucinky diltiazemu na átrioventrikulárny prevod u psa.

The effect of diltiazem on atrioventricular conduction was studied in pentobarbital anesthetized dogs, conscious dogs, and atropine pretreated conscious dogs. In anesthetized dogs diltiazem administration resulted in diminished heart rate and aortal pressure, as well as prolongation of the functional refractory period of the AV node and of AV conductance. The effective refractory period of the atria and intraatrial conductance were not affected. The function of the AV node was comparable in the three groups studied. An anticholinergic action of diltiazem affecting the AV node has thus to be excluded. The recorded slight increase in heart rate in conscious dogs may be accounted for by the activation of baroreceptors induced by decreased aortal pressure.

Inverse regulation of calcium channels and beta-adrenergic receptors in virus-transformed human embryonal cells.

Monolayer cultures of human embryonal smooth muscle cells (HEC) were used to study the heterologous regulation of membrane beta-adrenergic receptors and Ca2+ channels. The relationships between the activation of membrane bound alpha-1 and beta-adrenergic receptors, the cyclic nucleotide response and Ca2+ channel binding were studied in a cellular model of latent virus infection (Herpes simplex, Type-2) in a human embryonal cell line. In the early stage of infection (72 h), there was a significant increase in the cell cAMP content, followed by a decrease in the binding capacity of the beta-adrenergic ligand with an increased total number of the 1,4-dihydropyridine Ca2+ channel agonist (-)-S-(3H)BAYK 8644 binding sites on the cell membrane of infected cells. The increased numbers of Ca2+ agonist binding sites were accompanied by an increased cAMP content in the cells and an increased membrane ATP-ase activity. Down-regulation of (3H)DHA binding, and an increased capacity of Ca2+ agonist binding were found after prolonged exposure of HEC to isoprenaline (10(-5) mol.l-1). Stimulation of alpha-1 adrenergic receptors with phenylephrine (10(-6) mol.l-1) was accompanied with only slight but significant increase in (3H)DHA binding and with a significant reduction in the total number of Ca2+ channel agonist binding sites.

The beta-adrenergic receptor-regulated 1,4-dihydropyridine calcium channel receptor sites in coronary artery smooth muscle.

The cross-regulatory communication from beta-adrenergic receptors to 1,4-dihydropyridine (DHP) Ca2+ channel agonist and antagonist binding sites and cooperativity between DHP binding sites were studied in microsomal membranes of canine coronary artery (purified to a factor 2.9 for DHPs). The maximal number of binding sites (Bmax) identified in coronary artery microsomal membranes (CAM) with Ca2+ channel agonist (-)-S-(3H)BAY K 8644 was two times higher than Bmax of sites labelled with Ca2+ channel antagonist (+)-(3H)PN 200-110. The exposure of CAM to isoprenaline was accompanied with down-regulation of beta-adrenergic receptors and with increase in binding capacity for DHPs. The increase in Bmax was proportional in both groups of experiments and was related to increased affinity of DHPs. The 1,4-DHP binding sites identified in vascular smooth muscle showed characteristics typical for classification of specific 1,4-DHP receptor on Ca2+ channels. The binding was of high affinity, saturable and reversible, it showed stereoselectivity and it was positively modulated by beta-adrenergic stimulation and its showed cAMP and GTP sensitivity. The results support the hypothesis that beta-receptors also regulate the mode of Ca2+ channels in coronary artery smooth muscle.

[Chondrodysplasia punctata]. / K problematice chondrodysplasia punctata.

Authors deal with the classification of chondrodysplasia punctata, in detail they analyze the clinical and radiomorphological symptoms. From the diagnostic viewpoint it is important to evaluate typical X-ray epiphyseal changes in the first year of age of the affected child. Clinical symptoms vary and they are not typical only for this disease. They are often combined with various congenital developmental anomalies. The case study presents the correlation between X-ray epiphyseal changes in the knee and the arthroscopic findings.

[Vasodilating effects of etimizol in vitro and its relation to purinergic receptors]. / Vazodilatacné úcinky etimizolu in vitro a ich vztah k purínergickým receptorom.

The paper is concerned with the effect of the breath analeptic agent etimizole on the smooth muscle of vessels under in vitro conditions from the viewpoint of its assumed interaction with purinergic receptors. Isolated preparations of the coronary artery and a. dorsalis pedis of the dog served as experimental material. Etimizole administered in a cumulative manner in dependence on concentration decreases the strength of contraction of the preparations contracted with K+ ions. This relaxant effect, similarly as the effect of adenosine, is not affected by a removal of the endothelium, can be inhibited with theophylline and potentiated with dipyridamole. Etimizole in higher concentrations inhibits the response of vascular preparations to electrical stimulation. In the concentration of 10(-4) mol.l-1 it potentiates the relaxant effect of adenosine, the experimental effects not differing from the theoretical curve for the addition of effects. The obtained results support the assumption that the vasodilating effect of etimizole is mediated prevalently by P1 purinergic receptors.

[The role of exogenous factors in the etiology of congenital hip dislocation: a socio-epidemiologic study]. / Uloha exogénnych cinitel'ov v etiológii luxatio coxae congenita: socio-epidemiologická stúdia.

The authors present in their work the results of the analysis of the relation between congenital dislocation of vertebral joints and social factors which they have found out in 120 children singled out of 9516 live-born children in the Martin district (Slovakia) in the period 1979-1983. The investigation of social factors has been based on the analysis of socioeconomic and social conditions of the Martin district which has no regional particularities. According to their results the share of exogenous factors in the origin and development of this disease is manifested more frequently in the first-borns (having the highest representation in the examined group). On the top of the list of social indices, which they have examined in primiparae and multiparae respectively, there are unsuitable housing conditions (living in discord with mother-in-law in the same house-hold), high percentage of impregnation before marriage which can be considered a strain and longterm conflicting situation and can have together with other factors a sociopathogenetic effect.

Regulation of beta-adrenergic receptors and calcium channel agonist binding sites in cultured human embryonal smooth muscle cells.

Recent electrophysiological studies with cell membrane patches of cardiac myocytes and an electrically excitable cell line derived from rat pituitary tumor suggested that voltage activated calcium channels must be phosphorylated to respond to membrane depolarization (Armstrong and Eckert 1986; Trautwein and Kameyama 1986). In view of the "phosphorylation hypothesis" we investigated the adenylate-cyclase activity, the characteristics of beta-adrenergic and calcium channel agonist binding sites in control and desensitized (exposure to isoproterenol) human embryonal cells (HEC), and in fragmented membrane preparations of canine coronary smooth muscle. Our results suggest that down-regulation of the membrane-bound beta-adrenergic receptors, induced by isoproterenol in human embryonal cells and also in adult canine vascular tissue, results in physical translocation of beta-adrenergic binding sites into the light membrane fraction. This phenomenon is accompanied with an increased intracellular concentration of cAMP in and an increased binding of the calcium channel agonist (3H) BAYK 8644 to both HEC and canine smooth muscle membrane preparations. It could be concluded that phosphorylation of beta-adrenergic receptors regulates not only the beta subcellular distribution of the beta receptors but also the availability of calcium channel agonist binding sites in the cellular membrane.

Evidence that high affinity (3H)clonidine binding cooperates with H2-receptors in the canine coronary smooth muscle membrane.

We have investigated the effects of myocardial ischemia and exogenous histamine and 4-methylhistamine on the regulation of membrane bound alpha 2- and beta-adrenoreceptors (ARs) in the canine coronary artery smooth muscle (CAS). The results indicate that exposure of CAS to ischemia and histamine is associated with the stimulation of adenylate cyclase and with a down-regulation of alpha 2-ARs which is accompanied by the sequestration of alpha 2-AR sites into light membrane particles. The increased number of beta-AR sites in CAS represents a c-AMP mediated adaptational pathway in compromised CAS.