Discoordinate expression of IL-1α and IL-1β in interfacial membranes of failed joint prostheses

Bone resorption following either cemented or uncemented total hip replacement has been implicated as an important etiologic factor in aseptic loosening of prostheses, the most frequent cause of clinical failure. Interleukin-1 (IL-1), collagenase and prostaglandin E₂ are considered to play key roles in pathological bone resorption. We have measured the actual levels and quantified the genes coding for several cytokines [IL-1, IL-1, IL-4, IL-6, platelet-derived growth factors (PDGF), transforming growth factor- (TGF) and tumor necrosis factor- (TNF)] in interfacial membranes obtained from cemented or uncemented loosened joint replacements. IL-1, IL-6 and TNF were barely detectable in the interfacial membranes either at protein or mRNA levels, while IL-1 and TGF were found to be expressed at the highest levels in freshly isolated tissues. However, the expression of IL-1 increased 10–1000-fold either in isolated cells or explant cultures of interfacial membranes within 24 h. The expression of other cytokines, measured directly in tissue or cells, did not suggest a discoordinate expression of bone-resorbing cellular mediators.     

Nucleolar organization in granule cell neurons of the rat cerebellum

Summary The present light and electron microscopic study deals with the morphology and cytochemical properties of the nucleolus in mature granule cells of the rat cerebellum. Nucleolar organization has been examined by several different methodological approaches: (a) determination of the number of nucleoli per cell from smear preparations, (b) morphometric estimation of nucleolar size, and (c) ultrastructural and cytochemical characterization of nucleolar components. The mean number of nucleoli per cell was found to be 1.46 ± 0.02 (mean ± SEM). The morphometric measurement of the nucleolar area showed an average value of 0.359 ± 0.07 m² (mean ± SDM). At the electron microscope level, most granule cell nucleoli displayed a fine texture which does not differ substantially from the ring-shaped configuration usually found in cells with low levels of protein synthesis activity; i.e., a large round fibrillar centre surrounded by the dense fibrillar component, and small masses of granular component segregated from the preceding constituents. The meaning of this nucleolar configuration is discussed in the light of recent ultrastructural and biochemical data on nucleolar function. A relationship between this pattern of nucleolar organization and metabolic characteristics of the granule cells is suggested.     

Quality assurance of equipment in x-ray diagnostic departments

Scientific-Industrial Association Ékran, Moscow. Translated from Meditsinskaya Tekhnika, No. 3, pp. 8–10, May–June, 1992.     

Semiautomatic morphometric analysis of the nucleolar development in the nucl. n. oculomotorii of Tupaia belangeri during ontogenesis

Summary The development during ontogenesis of the nuclear and nucleolar diameters and of the numbers of nucleoli per nucleus in the nucl. n. oculomotorii of 32 male Tupaia belangeri are described. The measurements of the nucleolar diameters were done automatically using the Micro-Videomat (Zeiss, Oberkochen). Increase of the nuclear and nucleolar diameters yielded a nearly sigmoid-shaped curve, which was fitted using the logistic growth function. The ideal value of the nucleolar diameter is 3.7 m with a half value time of 22 days of ontogenesis and an enlargement factor of 1.53. The respective parameters for the nucleus are 12.2 m, 28 days and 1.27. The ratio of the nuclear to nucleolar diameters decreases exponentially during ontogenesis to a value of 3.3. The validity of these easily determinable morphologic parameters for the RNA-synthesis is discussed. The number of nuclei with 2 or 3 nucleoli decreases during ontogenesis. The relevance of this fact for cell counting is also discussed.Abteilungsvorsteher: Professor Dr. H.-J. KretschmannDirektor: Professor Dr. F. WingertSupported by Deutsche Forschungsgemeinschaft.     

Long-term hemodynamic effects of antihypertensive treatment

The cardinal hemodynamic disorder in established essential hypertension is increased total peripheral resistance. During exercise, the increase in stroke volume of the heart is abnormal. A 20-year follow-up study of the hemodynamics in essential hypertension demonstrated a progressive increase in total peripheral resistance and deterioration of the heart pump function. Long-term treatment with antihypertensive agents modifies the circulatory system in different ways. Vasodilators (angiotensin converting enzyme inhibitors, ₁-blockers, and calcium antagonists) all reduce total peripheral resistance, and in general, cardiac output, heart rate, and stroke volume remain unchanged. Calcium antagonists like verapamil and diltiazem reduce the heart rate approximately 10% during exercise, but since stroke volume increases, cardiac output is unchanged. Chronic treatment with conventional -blockers induces a permanent reduction in cardiac output and heart rate during exercise. In contrast, carvedilol — a ₁,₂-blocker with ₁-blocking activity — prevents the immediate increase in total peripheral resistance during acute -blockade. In 19 patients followed by hemodynamic measurements over 6–9 months, blood pressure was well controlled by carvedilol. During exercise, total peripheral resistance decreased 6% (P<0.05), and=" the=" reductions=" in=" heart=" rate=" and=" cardiac=" index=" were=" less=" than=" on=" conventional=">-blockade. Echo-Doppler studies showed a significant reduction in the intraventricular septum of 13%.     

Development of nucleolar apparatus in the chick primitive erythroid cells

The primitive erythroid line cells of chick embryos were studied during embryonic days 2–14 by means of a cytochemical method to investigate the appearance and frequency of the main nucleolar types. The populations of erythroblasts and erythrocytes were classified according to the presence of functionally dominant nucleoli in their nuclei. In the course of primitive erythroid cell differentiation and maturation, compact nucleoli and nucleoli with nucleolonemas (both supposed to be RNA biosynthetically active) were gradually replaced by ring-shaped nucleoli and finally by micronucleoli reflecting the reversible and irreversible inhibition of RNA synthesis, respectively. The occurence of the main nucleolar types and their values in primitive erythroid cells of the developing chick depend not only on the maturation stage of the blood cells, but also on the developmental stage of the chick embryo. In comparison with the definitive erythroid line of the post-hatching chick and hen, the cells of the chick embryonic primitive erythroid line possess relatively high values of active nucleolar types. These are still present in advanced maturation stages, and occur also as definitive erythroid lines of lower vertebrates.     

Histamine release “in vivo” and “in vitro” induced by hypnotics in normal and atopic patients

The in vitro test of histamine release induced in the leukocytes of atopic subjects selected according to specific criteria would seem to be much more accurate to study the histamine releasing characteristics of intravenous agents than the in vivo study in patients who have to be anaesthetised. Moreover, different concentrations of the test drug may be used, and thus the threshold for histamine release may be compared. It is the test which we recommend for investigating new drugs. However, it is lengthy and expensive; it can therefore not be recommended as a routine preoperative investigation.     

Contribution of group II phospholipase A2 to arachidonic acid release and prostaglandin synthesis by mesangial cells

Interleukin 1 (IL-1) and tumour necrosis factor (TNF) have been found to increase group II phospholipase A₂ (PLA₂) synthesis and secretion by mesangial cells. In all cases 85%–90% of the enzyme is secreted from the cells and a parallel increase in prostaglandin (PGE₂) synthesis is observed. We report here that co-incubation with a monoclonal antibody that specifically binds and neutralizes rat group II PLA₂ attenuates IL-1 and TNF-stimulated PGE₂ production by 45% and 52%, respectively. CGP43182, a specific inhibitor of group II PLA₂, potently blocks IL-1- and TNF-stimulated PGE₂ synthesis in intact mesangial cells with 1C₅₀s of 1.3 and 1.0 M, respectively.     

Is aspartic acid a regulator of hematopoiesis?

Ekaterinburg Branch of the All-Union Kurgan Restorative Traumatology and Orthopedics Research Center. Presented by Academician of the Russian Academy of Medical Sciences E. D. Gol'dberg.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 9, pp. 293–294, September, 1992.     

Identification and Characterization of the UL24 Gene Product of Herpes Simplex Virus Type 2

The UL24 gene of herpes simplex virus type 2 (HSV-2) is predicted to encode a 281 amino acid protein with a molecular mass of 30.5kDa. In this study, the HSV-2 UL24 gene product has been identified by using a rabbit polyclonal antiserum produced against a recombinant protein containing the full-length UL24 gene product of HSV-2 fused to glutathione-S-transferase. The antiserum reacted specifically with a 32kDa protein in HSV-2 186-infected Vero cells and with 31 and 32kDa proteins in UL24-expressing Cos-7 cells. Accumulation of UL24 protein to detectable levels required viral DNA synthesis, indicating that the protein was regulated as a late gene. UL24 protein was found to be associated with purified HSV-2 virions and C capsids. Indirect immunofluorescence analysis demonstrated that the UL24-specific fluorescence was detected in perinuclear regions of the cytoplasm and/or in the nucleus as small discrete granules from 9h post infection (hpi). Furthermore, the UL24 protein expressed singly was detected predominantly in the nucleus and slightly in the cytoplasm at 24h after transfection, with branch-like cytoplasmic protruding structures. Strong nucleolus staining was visible in partial cells.     

Potential role of cytokines in disseminated mycobacterial infections

Organisms belonging to theMycobacterium avium complex (MAC) are common pathogens in immunosuppressed and AIDS patients. This paper reviews the role of cytokines in the pathogenesis of MAC infection. MAC organisms mainly infect monocytes and macrophages, and the effect of HIV infection on susceptibility of macrophages to MAC infection is largely unknown. Both GM-CSF and tumour necrosis factor- can induce mycobacteriostatic/mycobactericidal activity in MAC-infected macrophages. The activity of interferon- on mycobacterial infection appears to be dependent on the type of macrophage: in murine peritoneal and human monocyte-derived macrophages, interferon- does not inhibit the intracellular growth of MAC, whereas in intestinal macrophages interferon- results in inhibition of MAC. Transforming growth factor-₁, interleukin-10 and interleukin-6 have all been shown to counteract the immunoactivating cytokines and MAC survival may be due to induction of these inhibitory cytokines within the macrophage. GM-CSF has been given to patients with disseminated MAC infection. Isolated macrophages from these patients demonstrated increased superoxide anion production and enhanced mycobacteriostatic/cidal activity compared with macrophages isolated from the same patients before GM-CSF treatment. These results suggest that GM-CSF may have potential in the treatment of MAC infection.     

Muramyldipeptide and granulocyte-macrophage colony-stimulating factor enhance interferon-γ-induced nitric oxide production by rat alveolar macrophages

Rat alveolar macrophages incubated with recombinant rat interferon- producel-arginine-dependent nitric oxide, which is rapidly decomposed into nitrite: this production by interferon- was markedly enhanced by granulocyte-macrophage colony-stimulating factor and muramyldipeptide, but not by other cytokines. The enhancement was dependent on the presence ofl-arginine in the incubation medium. It was based on a simple synergism between interferon- and muramyldipeptide and a priming effect of granulocyte-macrophage colony-stimulating factor for interferon--induced nitrite production. These data suggest that cytokine networks are important in the induction of nitric oxide in rat alveolar macrophages.     

Correlation between dose and pharmacological effects of cardiac peptides

Department of Experimental Cardiology, Research Institute of Cardiology, Tomsk Scientific Center, Russian Academy of Medical Sciences, Tomsk. Tsitomed National Medico-Biological Research and Production Complex, St. Petersburg. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 8, pp. 171–173, August, 1992.     

Main stages in the development of photooximetry

Scientific-Manufacturing Association Krasnogvardeets, St. Petersburg. Translated from Meditsinskaya Tekhnika, No. 1, pp. 5–10, January–February, 1993.     

Elevated Plasma Levels of 90K (Mac-2 BP) Immunostimulatory Glycoprotein in HIV-1-Infected Children

90K is a secreted serum glycoprotein with immune stimulatory activity. In this study, 90K plasma levels were determined by an enzyme-linked immunosorbent assay in 18 HIV-1-infected children and 10 uninfected control children. 90K levels in HIV-1-infected children (median, 12.5 g/ml) were higher than in HIV-1 uninfected control group (6.3 g/ml; P < 0.05). 90K levels of HIV-1-infected children classified as stage B and C (median, 15.0 g/ml and 22.7 g/ml, respectively) were higher compared to children with stage A disease (median, 7.0 g/ml; P < 0.05). A positive correlation (r = 0.5; P < 0.05) was found between 90K levels and HIV-1 RNA levels in 137 plasma samples of 18 HIV-1-infected children collected during a period of 1 year. No correlation was found between 90K levels and CD4 cell counts. These results suggest that 90K plasma levels may represent a novel marker of disease progression in HIV-1-infected children.