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PubMed1985

Effects of oximes, diacetylmonoxime, pyridine-2-aldoxime, and pyridine-2-aldoxime methochloride, on the electrical and mechanical activities of guinea pig cardiac ventricular muscles.

Effects of 3 oximes, diacetylmonoxime (DAM), pyridine-2-aldoxime (PAM) and pyridine-2-aldoxime methochloride (2-PAM), on the normal electrical and mechanical activities and on the slow response action potentials were examined in the guinea pig ventricular muscles. DAM and long-term exposure to high concentrations of PAM produced decreases in contractile force, action potential duration and slow response action potentials, whereas 2-PAM and low concentrations of PAM tended to increase these parameters. Thus, these 3 oximes did not act uniformly on cardiac muscle. It was speculated that DAM and high concentrations of PAM may act as slow channel inhibitors, whereas 2-PAM and low concentrations of PAM may act as slow channel activators.

Action Potentials↗

PubMedDate not supplied

Determination of polyacrylamide in soil waters by size exclusion chromatography.

Determination of polyacrylamide (PAM) concentration in soil waters is important in improving the efficiency of PAM application and understanding the environmental fate of applied PAM. In this study, concentrations of anionic PAM with high molecular weight in soil waters containing salts and dissolved organic matter (DOM) were determined quantitatively by size exclusion chromatography (SEC) with ultraviolet (UV) absorbance detection. Polyacrylamide was separated from interferential salts and DOM on a polymeric gel column eluted with an aqueous solution of 0.05 M KH2PO4 and then detected at a short UV wavelength of 195 nm. Analysis of PAM concentrations in soil sorption supernatants, soil leachates, and water samples from irrigation furrow streams showed that SEC is an effective approach for quantifying low concentrations (0-10 mg L(-1)) of PAM in waters containing soil DOM and salts. The method has a lower detection limit of 0.02 microg and a linear response range of 0.2 to 80 mg L(-1). Precision studies gave coefficients of variation of < 1.96% (n = 4) for > 10 mg L(-1) PAM and < 12% (n = 3) for 0.2 to 3 mg L(-1) PAM.

Acrylic Resins↗

PubMed2004

Tolerance induced by the lipopeptide Pam3Cys is due to ablation of IL-1R-associated kinase-1.

Stimulation of the human monocytic cell line Mono Mac 6 with the synthetic lipopeptide (S)-(2,3-bis(palmitoyloxy)-(2RS)-propyl)-N-palmitoyl-(R)-Cys-(S)-Ser(S)-Lys(4)-OH, trihydrochloride (Pam(3)Cys) at 10 microg/ml induces a rapid expression of the TNF gene in a TLR2-dependent fashion. Preculture of the cells with Pam(3)Cys at 1 microg/ml leads to a reduced response after subsequent stimulation with Pam(3)Cys at 10 microg/ml, indicating that the cells have become tolerant to Pam(3)Cys. The CD14 and TLR2 expression is not decreased on the surface of the tolerant cells, but rather up-regulated. Analysis of the NF-kappaB binding in Pam(3)Cys-tolerant cells shows a failure to mobilize NF-kappaB-p50p65 heterodimers, while NF-kappaB-p50p50 homodimers remain unchanged. Pam(3)Cys-tolerant cells showed neither IkappaBalpha-Ser(32) phosphorylation nor IkappaBalpha degradation but MyD88 protein was unaltered. However, IRAK-1 protein was absent in Pam(3)Cys-induced tolerance, while IRAK-1 mRNA was still detectable at 30% compared with untreated cells. In contrast, in LPS-tolerized cells, p50p50 homodimers were induced, IRAK-1 protein level was only partially decreased, and p50p65 mobilization remained intact. It is concluded that in Mono Mac 6 monocytic cells, inhibition of IRAK-1 expression at the mRNA and protein levels is the main TLR-2-dependent mechanism responsible for Pam(3)Cys-induced tolerance, but not for TLR-4-dependent LPS-induced tolerance.

Adaptor Proteins, Signal Transducing↗

PubMed1992

[Mechanisms of clearance of foreign bodies by macrophages].

Macrophages have specific functions related to the sites where they are found. Pulmonary alveolar macrophages (PAM) may play an important role the clearance of invading and degenerative substances from the alveolar spaces. To clarify the mechanisms of the clearance by macrophages, we studied the role of scavenger receptors (SR) and Fc receptors (FcR) of PAM. 1) SR: Expression and localization of SR in human PAM. Type I and II SRs were expressed in human PAM, and the two SRs were confirmed in the same cells by double staining method using polyclonal antibodies to the SRs. These SRs were localized on the cell membrane and the endosome in part. The expression of SR in PAM from normal nonsmokers, smokers and patients with pneumoconiosis was studied, but there were no differences among these groups. Kinetics of SR and acetylated low density lipoprotein (acLDL) in PAM. SR recognized acLDL, and SR and acLDL-Au conjugates were concentrated in a coated pit 2 min after incubation. The conjugates were then internalized in the endosome 5 min after incubation. A few acLDL-Au conjugates were present in the endosome near the nucleus, but most of them were found in the lysosome 10 min after incubation. SR was found in the Golgi apparatus 15 min after incubation. These results suggest that SR in PAM may play an important role in the removal of alveolar surfactant. 2) FcR: Effects of FcR mediated phagocytosis on O2-release and phagosome-lysosome fusion in the phagosome of PAM.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2005

[Pulmonary alveolar microlithiasis].

Pulmonary alveolar microlithiasis (PAM) is a rare, chronic lung disease characterized by extensive intra alveolar calcium and phosphate deposition throughout both lung parenchyma. Etiology and pathogenesis of PAM is not known. There are some hypothesis for etiology and pathogenesis of PAM but none of them are satisfactory. The incidence of PAM is high in countries such as Turkey, Italy and USA. There is a surprising discordancy between radiological appearance and clinical presentation. Chest X-ray appearance of PAM is almost pathognomonic. Patients with PAM may have all findings of interstitial lung disease in varying degrees as well as micro-nodules on their HRCTs. Patients with PAM usually asymptomatic until the underlying process affects alveolar gas exchange however patients may ultimately develop hypoxemia and cor pulmonale. A definitive therapy for PAM did not exist. Patients with advanced lung disease may benefit from lung transplantation.

Calcinosis↗

PubMed2006

Kinetics study on photochemical oxidation of polyacrylamide by ozone combined with hydrogen peroxide and ultraviolet radiation.

An investigation on the process of ozone combined with hydrogen peroxide and ultraviolet radiation has been carried out in order to establish the kinetics for photochemical oxidation of polyacrylamide (PAM) in aqueous solution. Effects of operating parameters, including initial PAM concentration, dosages of ozone and hydrogen peroxide, UV radiation and pH value on the photochemical oxidation of PAM, have been studied. There was an increase in photochemical oxidation rate of PAM with increasing of dosages of O3, H2O2 and ultraviolet radiation. Upon increasing of the initial PAM concentration, the photochemical oxidation rate of PAM decreased. Slight effect of pH value on the photochemical oxidation rate of PAM was observed in the experiments. The kinetics equation for the photochemical oxidation of PAM by the system has been established.

Acrylic Resins↗

PubMed1991

The role of leukocytes in the pathogenesis of fibrin deposition in bovine acute lung injury.

The peculiarly fibrinous nature of bovine acute lung injury due to infection with Pasteurella haemolytica A1 suggests an imbalance between leukocyte-directed procoagulant and profibrinolytic influences in the inflamed bovine lung. Calves with experimental pneumonia produced by intratracheal inoculation with P. haemolytica A1 developed acute locally extensive cranioventral fibrinopurulent bronchopneumonia. Pulmonary alveolar macrophages (PAM) recovered by segmental lavage from affected lung lobes were 30 times more procoagulant than PAM obtained from unaffected lung lobes and 37-fold more procoagulant than PAM from control calf lungs. Unlike the enhancement of procoagulant activity, profibrinolytic activity (plasminogen activator amidolysis) of total lung leukocytes (PAM and plasminogen activator neutrophils [PMN]) was decreased 23 times in cells obtained from affected lung lobes and also was decreased four times in cells obtained from unaffected lobes of infected animals. This marked imbalance in cellular procoagulant and fibrinolytic activity probably contributes significantly to enhanced fibrin deposition and retarded fibrin removal. In addition, PAM from inflamed lungs were strongly positive for bovine tissue factor antigen as demonstrated by immunocytochemistry. Intensely tissue factor-positive PAM enmeshed in fibrinocellular exudates and positive alveolar walls were situated such that they were likely to have, in concert, initiated extrinsic activation of coagulation in the acutely inflamed lung. These data collectively suggest that enhanced PAM-directed procoagulant activity and diminished PAM- and PMN-directed profibrinolytic activity represent important modifications of local leukocyte function in bovine acute lung injury that are central to the pathogenesis of lesion development with extensive fibrin deposition and retarded fibrin removal.

Animals↗

PubMed1990

Susceptibility to lysis of pulmonary alveolar macrophages by human lymphokine-activated killer cells.

In this study we addressed the question of whether lymphokine-activated killer (LAK) cells, besides killing neoplastic cells, may exert a certain degree of lysis on the normal counterpart; in particular we took into consideration the toxicity against pulmonary alveolar macrophages (PAM). We demonstrated that human LAK cells generated in vitro following incubation of peripheral blood mononuclear cells with recombinant interleukin 2 for 4 days were able to lyse normal PAM in a 4-h 51Cr release assay. Similarly, PAM recovered from patients suffering from nonneoplastic interstitial lung disorders, i.e., sarcoidosis and hypersensitivity pneumonitis, were shown to be susceptible to the cytotoxic function provided by LAK cells. Both autologous and allogeneic PAM were lysed by LAK cells, thus suggesting that the phenomenon we observed does not require a major histocompatibility complex restriction. Preincubation of PAM under study with gamma-interferon did not affect their susceptibility to the lysis mediated by LAK cells. Furthermore, cold target inhibition assay demonstrated that normal PAM could efficiently compete with both NK-sensitive and NK-resistant target lines for the binding sites on LAK cells, thus indicating that the putative receptor(s), or at least the mechanism of target recognition, is shared by PAM and these different target cell lines. The evidence herein provided that LAK cells are cytotoxic to normal, nontransformed PAM points out that the pathogenetic mechanisms involving this self-addressed lytic activity could account for some adverse reactions related to LAK/interleukin 2 immunotherapy.

Cell Line↗

PubMed1989

Importance of Lyt 2+ T-cells in the curative effectiveness of a low dose of melphalan for mice bearing a large MOPC-315 tumor.

We have previously demonstrated that the curative effectiveness of a low dose (2.5 mg/kg) of melphalan (L-phenylalanine mustard; L-PAM) for mice bearing a large s.c. (approximately 20 mm in diameter) MOPC-315 tumor and extensive metastases requires the participation of T-cell-dependent antitumor immunity in tumor eradication (S. Ben-Efraim et al., Cancer Immunol. Immunother., 15: 101-107, 1983). Here we show that the Lyt 2+ T-cells, and not the L3T4+ T-cells, participate in the cure of such tumor-bearing mice by a low dose of L-PAM. Specifically, depletion of Lyt 2+ T-cells from mice bearing a large MOPC-315 tumor by treatment with monoclonal anti-Lyt 2.2 antibody abolished the curative effectiveness of the low dose of drug. In contrast, depletion of L3T4+ T-cells from mice bearing a large MOPC-315 tumor by treatment with monoclonal anti-L3T4 antibody did not reduce significantly the curative effectiveness of the low dose of drug. Histological examination of tumor nodules on various days following low-dose L-PAM therapy revealed widespread lymphocytic infiltration by Day 5 following the chemotherapy, and this infiltration was drastically reduced when the L-PAM-treated tumor bearers were treated with either anti-Thy 1.2 or anti-Lyt 2.2 antibody but not with anti-L3T4 antibody. The antitumor immunity exhibited by Lyt 2+ T-cells derived from mice which were in the process of eradicating a large MOPC-315 tumor following low-dose L-PAM therapy was exploited successfully to confer systemic antitumor immunity to mice bearing a barely palpable tumor. Specifically, the adoptively transferred Lyt 2+ splenic T-cells, in conjunction with a subcurative dose of L-PAM, brought about the cure of most mice. The Lyt 2+ splenic T-cells from L-PAM-treated MOPC-315 tumor bearers were also found to be capable of exerting a direct potent lytic effect against MOPC-315 tumor cells in an antigen-specific manner. Thus, it is conceivable that the direct cytotoxic activity of Lyt 2+ T-cells for MOPC-315 tumor cells is responsible, at least in part, for the ability of the Lyt 2+ T-cells from L-PAM-treated MOPC-315 tumor bearers to bring about the eradication of the tumor burden not eradicated through the direct antitumor effects of the low dose of drug.

Animals↗

PubMed1985

Deactivation of guinea pig pulmonary alveolar macrophage responses to N-formyl-methionyl-leucyl-phenylalanine: chemotaxis, superoxide generation, and binding.

Incubation of pulmonary alveolar macrophages (PAM) with the synthetic chemotactic tripeptide, N-formyl-methionyl-leucyl-phenylalanine (FMLP) results in deactivation of PAM chemotaxis. The chemotactic response to 10(-8) M FMLP was inhibited 85% after 30 min of preincubation with 10(-6) M FMLP and 48% by 10(-8) M FMLP. Only the higher dose of FMLP (10(-6) M) caused deactivation of the chemotactic response to C5a (20%). Preincubation with partially purified C5a at a concentration of 100 microliter/ml produced a 32% inhibition of the PAM response to 10(-8) M FMLP. In contrast, preincubation with FMLP had no significant effect on superoxide generation, either at baseline or after stimulation. Levels of intracellular cyclic adenosine-3',5'-monophosphate (cAMP) increased in response to PGE1 in the presence of 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase inhibitor, but FMLP failed to induce a change in cAMP levels. Studies of 3H-FMLP binding were consistent with two populations of membrane receptors with different affinities. Preincubation of PAM with FMLP did not result in a reduction of maximal binding. We conclude that FMLP induces deactivation of PAM chemotaxis, but cross-deactivation occurs only after high dose treatment. Unlike the PMN, macrophage chemotactic activation is not accompanied by an elevation in cAMP levels. These observations suggest that PAM chemotaxis is influenced by prior exposure to chemotactic stimuli, but other aspects of the PAM response diverge from that of PMN. The mechanism of deactivation of PAM does not appear to result from a shift in the dose-response curve or decreased availability of membrane receptors, but may involve uncoupling of post-receptor cellular responses.

Animals↗

PubMed1987

Induction of hepatic veno-occlusive disease in dogs.

The authors attempted to induce hepatic veno-occlusive disease (VOD) in 64 dogs. Preparative treatments included combinations of total-body irradiation (TBI) or localized hepatic irradiation (LI) or both and chemotherapy consisting of dimethylbusulfan (DMB), L-phenylalanine mustard (L-PAM), methotrexate, or monocrotaline. VOD occurred infrequently in those dogs given 9.2 Gy TBI and DMB (1/10), TBI and/or LI (9.2-27 Gy) with L-PAM (2/36) or high dose methotrexate and LI (0/2). Specifically, VOD occurred in the dogs with a shorter interval between TBI and DMB or in the dog that received the glutathione reductase inhibitor, buthionine sulfoximide (BSO) before L-PAM. In contrast, among 17 dogs given monocrotaline, 8 developed VOD, particularly when used with L-PAM +/- irradiation (7/13). The major cause of death, early gastrointestinal toxicity, was further augmented by higher doses of irradiation, by shortening the interval between LI and L-PAM administration to less than 4 weeks, and administering BSO or monocrotaline before L-PAM. Gastrointestinal toxicity was lessened by giving low dose cyclophosphamide given before L-PAM. VOD can be produced in dogs especially with monocrotaline or BSO given before and L-PAM +/- irradiation. However, gastrointestinal toxicity renders the study of VOD beyond the acute phase difficult. Nevertheless, this approach appears useful for the study of VOD in other animals and for developing agents aimed at preventing VOD.

Animals↗

PubMed1988

Interleukin-3 (IL-3) stimulates the clonal growth of pulmonary alveolar macrophage of the mouse: role of IL-3 in the regulation of macrophage production outside the bone marrow.

Interleukin-3 (IL-3) is one of the hematopoietic growth factors that regulates the growth and differentiation of pluripotent stem cells, thereby leading to the production of all the major blood cell types. The role of IL-3 in the regulation of pulmonary alveolar macrophage (PAM) production was investigated. IL-3 stimulated the proliferation and clonal growth of murine PAM with a dose-response curve similar to that of bone marrow granulocyte-macrophage colony-forming cells. The IL-3-induced colony formation by cells outside the bone marrow appeared to be unique to PAM; IL-3 failed to cause colony formation by both peritoneal exudate macrophages (PEM) and blood monocytes. Unlike bone marrow stem cells, PAM are unipotential and in vitro gave rise to only mononuclear phagocytes under the influence of IL-3. Nevertheless, cells derived from PAM cultures in media containing IL-3 displayed a high degree of heterogeneity in terms of their Fc receptor-mediated phagocytic activity. At low concentrations, IL-3 induced a synergistic response with colony-stimulating factor 1 (CSF-1), which resulted in an enhanced proliferative capacity of PAM. A synergistic effect was also observed by short-term exposure of PAM to IL-3 followed by incubating with CSF-1 alone. This study shows that IL-3 exhibited a macrophage growth factor activity unique to PAM.

Animals↗

PubMed1976

Enzymatic attack on side chains of synthetic polymers. Chymotrypsin-catalyzed hydrolysis of specific substrate groups attached to acrylamide or acrylic acid co-polymers.

Three vinyl monomers, M-1, M-3, and M-5, in which L-phenylalanine p-nitroanilide was acylated with CH2==CHCONH(CH2)nCO--(n = 1, 3, 5) were synthesized. They were co-polymerized with a large excess of acrylamide (co-polymers PAm-1, PAm-3, and PAm-5) and with a large excess of acrylic acid (co-polymers PAc=1, PAc-3, and PCc-5). In addition, M-5 was co-polymerized with acrylamide containing 2.8 mol % of the hydrophobic monomer N-acrylyl-1-naphthylamine (co-polymer PAm-5N). The rates of the chymotrypsin-catalyzed hydrolysis of the nitroanilide groups of M-5 and the various co-polymers were determined over a range of pH. For some of the systems data were also obtained over a range of substrate concentrations to derive values for Vmax and Km. Results obtained with PAm-5 were found to be independent of the chain length of the co-polymer. At pH 7, 25 degrees and with 2.7 X 10(-6) M enzyme, Vmax values for M-5, PAm-k, PAm-5N, and PAc-5 were 5.5, 5.5, 10, and 3.6 X 10(-8) M/S, while Km values were 8.5, 16.5, 10, and 2.2 X 10(-5),respectively, With PAc-5, the pH activity profile was shifted to higher acidities as compared to the profiles obtained with M-5 and PAm-5. The susceptibility of the co-polymers to chymotrypsin attack decreases sharply with a decreasing spacing of the L-phenylalanine p-nitroanilide residue from the backbone of the polymer chains.

Acrylamides↗

PubMed1980

Effects of Diesel engine exhaust on pulmonary alveolar macrophages.

The in vivo effects of inhalation of diesel engine exhaust (DEE) on pulmonary alveolar macrophages (PAM) was studied in 73 guinea pigs and 48 rats. Animals were exposed in individual cages in special chambers to 3 different dose levels of DEE expressed in terms of the concentation of soot or carbon particles (-P); 250, 1500, 6000 micrograms DEE-P/M3. Exposure durations for guinea pigs were 1 and 3 days, 1 and 2 weeks, 2, 4, 8 and 12 months while rats were exposed 1, 2, 4, 8 and 12 months. Age matched controls were similarly exposed concurrently to "clean" air. PAM obtained by bronchopulmonary lavage from exposed animals had viabilities comparable to controls. PAM diameters and relative surface areas increased 2--3 fold over controls and in relation to both the dose of DEE-P given and the exposure duration. Most of the in vivo exposed PAM had phagocytized DEE-P which did not appear to be cytotoxic and remained confined in phagosomes as discrete particles with diameters of 0.014--0.072 micrometer. Ability of PAM to adhere and spread on test surfaces was greater in the DEE-P sets than in controls. DEE-P containing PAM were still able to phagocytize latex particles when fed in vitro. However, such PAM had defective phagocytosis ability, and did not in the same time interval take up as much fluorescent latex as controls when studied by flow system technology. Absolute numbers of PAM in guinea pig lavages from exposures to 250 and 1500 microgram DEE-P/M3 for 2 months were not significantly changed over concurrent controls. Exudative leukocytes (eosinophils in guinea pigs and neutrophils in rats) appeared in the lavage in greater numbers as dose and duration of exposure increased. Another species difference was the appearance in DEE-P exposed guinea pig lavages of "reactive" monocytes.

Animals↗

PubMed1980

Plasma requirement for the aggregation of rabbit platelets by an aggregating material derived from SV40-transformed 3T3 fibroblasts.

Certain tumors require platelets for metastases, and many of these aggregate platelets in vitro. We have studied their in vitro interaction by extracting a PAM from SV40-transformed 3T3 fibroblasts. The preparation is enriched with membrane vesicles and requires an intact sedimentable sialolipoprotein for activity. PAM aggregates platelets after a lag period (J Lab Clin Med 93:332, 1979) and requires plasma as a cofactor(s). Two plasma components have been identified with the use of PRP or GFP. The first component shortens the platelet aggregation lag period after preincubation of PAM with plasma at 37 degrees C for 10 min prior to its addition to PRP or GFP and is labile to heating at 56 degrees C for 30 min. However, the activated PAM (formed by incubation with plasma at 37 degrees C) is stable at 56 degrees C for 30 min. This labile factor appears to be a component(s) of the complement alternative pathway, since it is inactivated by treatment of plasma with cobra venom or zymosan; and guinea pig PRP deficient in C' 4 can be aggregated by PAM. The second component is a plasma factor that is stable to heating at 56 degrees C. Activated PAM can be sedimented at 100,000 x g. The sediment, when suspended in Veronal buffer, pH 7.4, does not aggregate GFP, however, addition of plasma heated at 56 degrees C restores the platelet aggregation response. Thus a material extracted from SV40 3T3 fibroblasts aggregates platelets in vitro in the presence of two factors: (1) a component(s) of the alternative complement pathway that activates PAM and shortens the platelet aggregation lag period and (2) a heat-stable factor that is required for activated PAM to aggregate platelets.

Animals↗

PubMed1984

The pulmonary alveolar macrophage.

The pulmonary alveolar macrophage (PAM) occupies a unique environment, with exposure to both the atmosphere and the blood stream. This position enables the PAM to perform its primary role of protecting the lung from inhaled, potentially damaging, agents. The effects of long term cigarette smoking on the human PAM appear to be functionally minimal when the cells are studied as a group, but the marked recruitment of PAM's which occurs in smokers leads to a greater potential for PAM helpful and/or damaging activity within the lung. The traditional role of phagocytosis is not a global function of the unstimulated human PAM. Of increasing importance for the understanding of pulmonary disease is the ability of the PAM to modulate lymphocyte, polymorphonuclear leukocyte and fibroblast activity. These functions are primarily for the defence of the lung but often produce temporary or permanent lung damage. Subclassification of the human PAM based upon functional heterogeneity may lead to a better understanding of the role of this cell.

Animals↗

PubMed1982

Filtration deformability of rabbit pulmonary macrophage.

Rabbit PAM deformability was evaluated by positive-pressure filtration through Nucleopore membranes of well-specified pore diameter. The PAM filtration method was standardized and was influenced by apparatus variations (pore size, flow rate, cell concentration), environment (temperature, pH, divalent cations, protein concentration), and differences in PAM cell volume. The influence of phagocyte function on filtration deformability was evaluated by exposing PAMs to pharmacologic and physiologic agents with somewhat exclusive influences on phagocyte physiology. Agents that interact with microfilament contractile protein (N-ethylmaleimide, cytochalasin B) altered deformability profoundly, but no effect was observed with agents interacting with microtubules (vinblastine, colchicine). Agents that cause general PAM activation (phorbol myristate acetate) or stimulate chemotaxis (F-Met-Leu-Phe) increased deformability. On the contrary, PAM deformability was not changed by phagocytosis of Staphylococcus aureus or latex beads. Pharmacologic agents that alter PAM adhesion (aspirin, indomethacin, physiologic dose hydrocortisone) or inhibit glycolysis (2-deoxyglucose) had no influence on filtration deformability. Filtration PAM deformability reflects passive whole cell rigidity, which appears to be determined by the state of polymerization of the actin-myosin microfilament complex.

Animals↗

PubMed1981

[Hemodynamic correlation of the systolic movement of the aortic root].

Factors influencing the anterior systolic movement of the aortic posterior wall (PAM) are complex and still controversial. Left atrial events seem to be more important that stroke volume or left ventricular function in determining PAM. Even if the reduction of systolic aortic movement is generally associated to a severe impairment of left ventricular function, very few studies correlate the changes in the amplitude of aortic systolic movement to the hemodynamic pattern. In 50 patients posterior aortic wall echocardiograms, right heart catheterization and 99mTc angiocardiography were performed within 24 h. According to hemodynamic and left ventricular wall motion parameters 18 patients resulted to have a normal (1st group) and 32 patients (2nd group) an impaired left ventricular function. In the 2nd group mean values of PAM were significantly lower than in the 1st group (7.4 +/- 2.9 mm vs 10.2 +/- 1.9 mm). A significant correlation was found between PAM and hemodynamic parameters, i.e. CPW (r = 0.58), EF (r = 0.58) and SV (r = 0.40), whereas no significant correlations were found between these parameters and left atrial dimensions and between PAM and left atrial dimensions. A high significant correlation was found between PAM and echocardiographically measured septal wall motion (r = 0.80). All patients with PAM Less Than 6 mm and echo septal wall motion Less Than 5 mm had an akinesis or a dyskinesis of septal wall quantitatively determined with 99mTc angiocardiography. These findings suggest that one of the main determinants of PAM is left ventricular wall motion and in particular left ventricular septal motion.

Aorta↗