Synergistic effects of mineral fibres and cigarette smoke on the production of tumour necrosis factor by alveolar macrophages of rats

The objective of this study was to evaluate the combined effects of mineral fibres and cigarette smoke on the production of tumour necrosis factor (TNF) by alveolar macrophages. Rats were exposed to cigarette smoke in vivo, and production of TNF by alveolar macrophages was measured in the presence of mineral fibres in vitro. For smoke exposure, rats were divided into two groups. Five were exposed to a daily concentration of 10 mg/m3 of cigarette smoke for an eight hour period, and five rats (controls) were not exposed to smoke. Bronchoalveolar lavage was performed after exposure to smoke and the recovered alveolar macrophages were incubated with either chrysotile or ceramic fibres on a microplate for 24 hours. Activity of TNF in the supernatant was determined by the L-929 fibroblast cell bioassay. When alveolar macrophages were not stimulated by mineral fibres, production of TNF by rats exposed to smoke and unexposed rats was essentially the same. When alveolar macrophages were stimulated in vitro by chrysotile or ceramic fibres, production of TNF by alveolar macrophages from rats exposed to smoke was higher than that by alveolar macrophages from unexposed rats. The findings suggest that cigarette smoke and mineral fibres have a synergistic effect on TNF production by alveolar macrophages.     

Asbestos fibres and man made mineral fibres: induction and release of tumour necrosis factor-alpha from rat alveolar macrophages

OBJECTIVES: Mounting evidence suggests that asbestos fibres can stimulate alveolar macrophages to generate the potent inflammatory and fibrogenic mediator, tumour necrosis factor-alpha (TNF-alpha), and that this may play an important part in the onset and development of airway inflammation and lung fibrosis due to asbestos fibre inhalation. Little is known, however, about the ability of other mineral fibres to initiate formation and release of TNF-alpha by alveolar macrophages. Therefore the effects of different fibres (crocidolite, chrysotile A, chrysotile B, two man made mineral fibres (MMVF 21 and MMVF 22), a ceramic fibre (RCF 1), and a silicon carbide whisker fibre (SiCwh)) on formation and release of TNF-alpha by rat alveolar macrophages were examined. METHODS: Cells were isolated and incubated at 37 degrees C with the different fibres, or with culture medium alone (controls), and the amounts of TNF-alpha messenger RNA (mRNA) in the cells and TNF-alpha bioactivity released into the culture medium were measured at different time points. RESULTS: Significantly (P < 0.05 v control) increased amounts of TNF-alpha mRNA were found in cells exposed to crocidolite, chrysotile A, chrysotile B, MMVF 21, RCF 1, or SiCwh for 90 minutes, and significantly (P < 0.05 v control) increased activities of TNF-alpha were found in the medium of macrophages exposed to crocidolite, chrysotile A, chrysotile B, or MMVF 21 for four hours. CONCLUSION: These observations suggest that not only natural mineral fibres but also certain man made mineral fibres are able to induce the formation and release of TNF-alpha by alveolar macrophages in vitro.     

In vitro induction of aryl hydrocarbon hydroxylase in human pulmonary alveolar macrophages by benzanthracene

Aryl hydrocarbon hydroxylase (AHH) was induced in human pulmonary alveolar macrophages (PAMs) cultured in the presence of benzanthracene. Time and dose--response curves were established for in vitro induction of this enzyme system in PAMs. In addition, a positive correlation was noted between the level of AHH activity in freshly lavaged PAMs and the in vitro inducibility of the enyzme in these cells from either nonsmokers or cigarette smokers. Measurements of the inducibility of AHH in cultured human PAMs provide an experimental system suitable for studying the mechanisms responsible for the initiation of pulmonary carcinogenesis.     

Tumor necrosis factor alpha is involved in the induction of plasminogen activator inhibitor-1 by endotoxin

We report a boy 20 months of age with encephalopathy, petechiae, and ethylmalonic aciduria (EPEMA). Other clinical features were severe hypotonia, orthostatic acrocyanosis, and chronic diarrhea. Magnetic resonance imaging (MRI) of the brain demonstrated bilateral lesions in the lenticular and caudate nuclei, periaqueductal region, subcortical areas, white matter, and brainstem. Short and medium chain Acyl-CoA dehydrogenase and cytochrome c oxidase (COX) activities in fibroblasts were normal. Muscle histochemistry disclosed diffuse COX deficiency, and respiratory chain activities in muscle disclosed severe COX deficiency. Twelve other patients with similar clinical features have been reported. Muscle COX activity, studied only in four, demonstrated a clear-cut defect.     

The growth response to tumour necrosis factor alpha of human gynaecological cancer cell lines

Academic computing initiatives rank high on the list of priorities of many dental schools. However, outcomes of academic computing initiatives have not been presented. The objectives of this program evaluation were to: 1) document a strategic initiative for academic computing over a five-year period; 2) assess outcomes; and 3) demonstrate how outcomes assessment changed strategic goals for the future. In 1992, Temple University School of Dentistry developed an academic computing plan. The plan proposed to develop the computer literacy of faculty, teach students the computer skills they need to be successful in their careers, and introduce computer-aided instruction as a new teaching tool. Before a new five-year plan was developed in 1997, the original plan's outcomes were summarily assessed. Assessment instruments included faculty and student surveys, budgets, inventory records, and utilization statistics. The school has reached two of three goals of the 1992 plan. Eighty percent of all full-time faculty have computers, are computer literate, and use computers for a variety of purposes. The school has implemented a comprehensive predoctoral dental informatics curriculum. However, the implementation of computer-aided instruction has not met expectations. Goals of the 1998-2003 plan include establishing an online learning infrastructure, improving student access, implementing computer-based oral health records, and further improving the computer literacy of faculty and students. Planning and supporting academic computing initiatives is a substantial challenge. Factors such as institutional culture, capital investment, ongoing support, and technological change influence plans and their success. While process and structure can be assessed relatively easily, measures for changed educational outcomes are still lacking.     

Comparison of endotoxin release by different antimicrobial agents and the effect on inflammation in experimental Escherichia coli meningitis

In a rabbit Escherichia coli meningitis model, endotoxin liberation and concentrations of leukocytes, tumor necrosis factor (TNF), and lactate were compared after a single intravenous dose of cefotaxime, cefpirome, meropenem, chloramphenicol, or gentamicin. These antibiotics caused a 2- to 10-fold increase in cerebrospinal fluid concentrations of free (filterable) endotoxin within 2 h of starting treatment. By contrast, free endotoxin concentrations increased almost 100-fold in untreated animals 4 h later as bacteria continued to multiply. An initial enhancement of inflammation in the central nervous system occurred in all treatment groups compared with untreated controls. No significant differences were observed between treatment groups except for lower TNF concentrations in chloramphenicol-treated animals. Antibiotic therapy in E. coli meningitis, irrespective of the agent used, may result in an increase in free endotoxin and enhancement of inflammation, but the amount of endotoxin liberated is considerably smaller than that shed by untreated bacteria.     

The promoting effect of tumour necrosis factor alpha in radiation-induced cell transformation

The aim of this study was to evaluate the efficacy and safety of gemcitabine, a pyrimidine antimetabolite, in the treatment of advanced transitional cell carcinoma of the urinary tract. 35 patients with unresectable or metastatic transitional cell carcinoma of the urinary tract previously treated with a platinum-based regimen were studied. Gemcitabine was administered at a dosage of 1200 mg/m2 as a 30-min intravenous infusion on days 1, 8 and 15, repeated every 28 days. 31 patients were evaluable for efficacy. 4 patients achieved a complete response (12.9%), 3 a partial response (9.6%) and 13 (42%) were stable for at least 4 weeks (overall response 22.5%; 95% confidence interval 8-37%). The median response duration was 11.8 months (range 3.6-17.7 + months) and median survival for all patients entered was 5 months (range 2-21 + months). 2 patients with complete response are still alive with no evidence of disease after 14 and 21 months. Gemcitabine also provided subjective symptomatic relief from pain, cystitis, dysuria, haematuria and peripheral oedema. Patients experienced little WHO grade 3-4 toxicity, with anaemia in 8 patients (23%), thrombocytopenia in 5 (14.2%), leucopenia in 4 (11.4%) and neutropenia in 7 (20%). WHO grade 3-4 hepatic toxicity occurred in 4 patients (11.4%) and transient elevations of transaminase was noted in 3 (8.6%). No patient had WHO grade 3-4 elevation of serum creatinine level. There was no WHO grade 4 symptomatic toxicity and no alopecia was noted. Transient influenza symptoms with gemcitabine occurred in 18 patients (51.4%) with 13 patients (37.1%) experiencing fever (2.9% WHO grade 3). In conclusion, gemcitabine is an new active agent for the treatment of transitional cell carcinoma of the urinary bladder with a mild toxicity profile; it warrants further investigation in combination with cisplatin in chemotherapy naive patients.     

Chlorpromazine inhibits tumour necrosis factor synthesis and cytotoxicity in vitro

Chlorpromazine (CPZ) has been previously shown to protect against endotoxin [lipopolysaccharide (LPS)] lethality and inhibit the release of tumour necrosis factor in vivo. We investigated at the cellular level whether this was due to direct inhibition of tumour necrosis factor-alpha (TNF-alpha) synthesis, using LPS-stimulated THP-1 human monocytic leukemia cells. We also studied the effect of CPZ on human TNF-alpha action by assessing TNF-alpha cytotoxicity on mouse fibrosarcoma L929 cells. CPZ (1-100 microM) inhibited TNF-alpha production in THP-1 cells in a dose dependent manner by a maximum of 80%. This effect was comparable to that of two well-known inhibitory drugs, dexamethasone and cyclicAMP. Inhibition was also evident at the mRNA level. On the other hand CPZ (10-25 microM) also inhibited TNF-alpha activity: in fact it reduced the cytotoxicity of TNF-alpha on L929 cells (EC50 was increased four times) and could provide protection even as a post-treatment. CPZ inhibited TNF-induced apoptosis in L929 cells, as detected by analysis of nuclear morphology. However, since we showed that apoptosis was very limited, and was not the main mode of cell death in our conditions, this could not explain the overall protection. Since CPZ did not interfere with either the oligomerization state of TNF-alpha or its receptor binding, our data suggest that it reduced cytotoxicity by inhibiting some steps in the TNF-alpha signalling pathways.     

Priming and induction of eosinophil trafficking in guinea-pig cutaneous inflammation by tumour necrosis factor alpha

This work addresses the fundamental limits imposed by the MRI process on the accuracy with which vessel diameters and cross-sectional areas can be derived from time-of-flight (TOF) and phase-contrast (PC) MR source images. By means of simulations and in vitro experiments, it is demonstrated that, even in the absence of flow-related artifacts, severe inaccuracies in the determination of diameters or cross-sectional areas may occur solely because of the physical process of the MR image acquisition. Resolution and intraluminal saturation have strong effects on the vessel appearance and thus on the diameter estimation error. It is shown that low resolution leads to diameter overestimation or even underestimation and that intraluminal saturation causes severe underestimation, even for relatively low flip angles. Velocity and velocity encoding do not have a major influence on lumen appearance in PC images. Accurate diameter estimations can be attained only if lumen diameters constitute at least three pixels for both TOF and PC acquisitions, provided that intraluminal saturation is suppressed or avoided. Additionally, since the constitution of TOF and PC images is dissimilar, lumina should be analyzed differently to obtain accurate diameters and cross-sectional areas.     

Distinct tumor necrosis factor-alpha responses in alveolar and peritoneal macrophages are associated with local levels of endotoxin

Tumor necrosis factor alpha (TNF-alpha) responses of alveolar macrophages (AMs) and peritoneal macrophages (PMs) were studied in rats after intravenous injection of lipopolysaccharide (LPS). High levels of plasma TNF-alpha, increased pulmonary myeloperoxidase activity, and leukopenia occurred within 2 h after LPS injection. Alveolar spaces exhibited a strict compartment property, as manifested by only slightly increased LPS and TNF-alpha levels in alveolar lavage fluid and an unchanged capacity of AMs to produce TNF-alpha. By contrast, the peritoneal cavity had greatly increased local LPS and TNF-alpha levels and a diminished PMs TNF-alpha response to LPS. The amount of LPS in the alveolar spaces was less than 0.2% of the level in peritoneal fluid. These results indicate that activation of resident macrophages is dependent on the amounts of local LPS and, in addition, suggest that resident AMs neither participate in the plasma TNF-alpha response nor contribute to neutrophil sequestration in the lung during the early stages of endotoxemia.     

The effect of endotoxin on in vivo rat alveolar macrophage phagocytosis

This study was performed to explore whether alveolar macrophage (AM) phagocytosis would be impaired during endotoxemia. Therefore, we characterized in vivo AM phagocytic function in rats following either intravenous (i.v.) or intratracheal (i.t.) administration of lipopolysaccharide (LPS). The i.v. administration of LPS to rats at dosages of 0, 1, 2, and 5 mg/kg showed that increasing LPS doses were significantly associated with increased AM phagocytosis of 198Au colloid (P < .01), decreased recovery of AMs in bronchoalveolar lavage (BAL) (P = .017), no significant differences in neutrophil recovery by lavage (P = .15), or in the concentration of albumin in BAL (P = .14). Across the dosages of LPS administered i.t. (i.e., 0, 1, 5, and 10 mg/kg), there was no difference in AM phagocytosis (P = .29), a significant decrease in AM recovery (P = .002), a significant increase in neutrophil number (P = .01), and little effect on the concentration of albumin (P = .06). Thus, we found that the administration of endotoxin to rats did not impair in vivo AM phagocytic function. In fact, our findings suggest that the i.v. administration of LPS may increase AM phagocytosis of 198Au.     

Tumor necrosis factor (TNF) induction from monocyte/macrophages by Candida species

Candida albicans was studied for its capacity to induce TNF production from mouse peritoneal macrophages (PM phi). TNF activities in the culture supernatants of Candida-stimulated PM phi and human peripheral blood monocytes were assessed by L 929 bioassay and ELISA respectively. C. albicans induced TNF production from PM phi and human peripheral blood monocytes in a dose-dependent manner. Although the capacity was lesser than live form, heat-killed C. albicans was also found to be capable of stimulating PM phi to induce TNF. The filtered supernatant of 24 h cultured live C. albicans had no effects on TNF production from PM phi. Saccharomyces cerevisiae-extracted mannan, a yeast cell wall antigen, induced TNF production from PM phi in a dose-dependent manner. Thus, the effect of C. albicans on TNF production from PM phi was seemed to be directly related to the presence of the yeast cell wall itself. Compatible with these data, when various candida species (C. albicans, C. tropicalis, C. pseudotropicalis. C. lusitaniae, C. krusei, C. parapsilosis, C. guilliermondii, C. stellatoidea, C. glabrata) and S. cerevisiae were compared to each other, at a concentration of 2 x 10(6) yeast cells/ml from each species, it was observed that TNF inducing capacities varied. Among the species used in this study, C. guilliermondii and C. glabrata, of which the yeast cell size were the smallest ones, were found to be less potent than that of others to induce TNF from PM phi.     

Morphofunctional characteristics of alveolar macrophages under the effect of a toxic factor

The work was conducted on Wistar rats who had received orally the xenobiotic hexachlorocyclohexane (HClCH) in different doses. The sizes of the alveolar macrophages and type II pneumocytes as well as the parameters of macrophage phagocytosis were studies. Administration of HClCH in subtoxic doses not exceeding the pesticide residues in the food in the first two months stimulated synthesis of the surfactant and its phagocytosis by the alveolar macrophages; further administration of the primer led to exhaustion of the cell function. A toxic HClCH dose induced synchronous stimulation of the functional interaction of the alveolar macrophages and type II pneumocytes by the end of the second month. Synthesis of the surfactant and its phagocytosis were stabilized in the period of the after-effect of the drug.     

Taurolidine inhibits tumour necrosis factor (TNF) toxicity--new evidence of TNF and endotoxin synergy

The use of recombinant tumour necrosis factor (TNF) in the treatment of solid tumours has been limited by life threatening toxicity. In addition TNF may be a major mediator of the effect of endotoxins. Recent evidence suggested that a synergism between endotoxin (at the picogram level) and TNF may contribute to this toxicity. The use of the anti-endotoxin taurolidine may reduce TNF toxicity by interfering with this synergy. C57/BL6 mice (n = 140) received toxic doses (12 micrograms/mouse IV) of TNF. Four groups were studied. Group A received taurolidine 200 mg/kg IV 30 minutes before TNF, group B received TNF followed 30 minutes later by taurolidine 200 mg/kg IV, group C received an identical volume (0.5 ml) of normal saline 30 minutes prior to TNF, and group D taurolidine 200 mg/kg IP 45 minutes before TNF. The mortality rate of those mice receiving intravenous taurolidine 30 minutes prior to TNF was 8.8%. This was significantly less (P < 0.005) than the mortality rate achieved in groups B, C and D (33% vs 39.4% vs 50%). Further experiments employing an MTT (3-(4,5-dimethylthinzol-2-microliters)-2,5-diphenyl tetrazolinm bromide) assay showed that this was not due to direct interaction of taurolidine with TNF but is likely to be due to interference with the synergistic effects of endotoxin and TNF. It was also demonstrated in cotherapy studies in a murine model that taurolidine did not reduce the anti-tumour efficacy of TNF against the TNF sensitive mouse fibrosarcoma cell line Meth-A sarcoma.     

Amiodarone-induced pulmonary toxicity in Fischer rats: release of tumor necrosis factor alpha and transforming growth factor beta by pulmonary alveolar macrophages

Amiodarone is an antiarrhythmic drug with numerous side effects, the most serious being the development of pulmonary toxicity. We have previously reported that a single intratracheal instillation of amiodarone to Fischer 344 rats results in pulmonary fibrosis within 6 wk of treatment. Presently, the mechanism of amiodarone-induced pulmonary toxicity is unknown. Cytokines that stimulate fibroblast proliferation and/or collagen production may play a role in amiodarone-induced pulmonary toxicity. To investigate this possibility, female rats were given a single intratracheal instillation of amiodarone (6.25 mg/kg), its metabolite desethylamiodarone (5 mg/kg), or vehicle (sterile water). At 1, 2, 3, or 6 wk after treatment the lungs were lavaged and the recovered cells were counted and identified. The alveolar macrophages were isolated by attachment to plastic petri dishes, cultured overnight, and the spent media collected for tumor necrosis factor alpha (TNF-alpha) and transforming growth factor beta (TGF-beta) analyses. Desethylamiodarone treatment resulted in a neutrophilic alveolitis, but the levels of TNF-alpha and TGF-beta were not significantly different from control animals. In contrast, amiodarone treatment resulted in a lymphocytic alveolitis and significantly higher amounts of TNF-alpha were observed at 3 and 6 wk after treatment. A trend toward higher levels of TGF-beta was also noted in the amiodarone-treated group at wk 1-3 but the values were not significantly different from those of controls. In conclusion, the release of TNF-alpha may play a role in the development of amiodarone-induced pulmonary toxicity.     

The effect of splenectomy on alveolar macrophages morphology and function

OBJECTIVE: To study the morphological and functional changes of pulmonary alveolar macrophages of rats after splenectomy, and the applied effects of splenic tissue autotransplantation in practice. METHODS: 87 Wistar rats were randomly divided into shamoperation group, splenectomy group and splenic tissue autotransplantation group. Six months after splenectomy, alveolar macrophges were subjected to brochoalveolar lavage described by Shennib. The dynamic survival and adherent rate of alveolar macrophages in culture, lysosomal enzyme content, hydrogen peroxide production and expression level of interleukin 1 (IL-1) activity of alveolar macrophages were quantitatively measured. The alveolar macrophages ultrastructure was observed by utilizing transmission electron microscope. RESULTS: The splenectomized rat's alveolar macrophages were different from alveolar macrophages of sham-operated rats. Their surface filopodia was reduced and shortened, lysosome fewer and its acid phosphatase quantity decreased, adherence postponed, hydrogen peroxide production and expression of IL-1 activity impaired. Splenic tissue autotransplantation fairly restored the splenic effects on maturation and function of alveolar macrophages. CONCLUSION: Splenic tissue autotransplantation is a simple useful operation for preserving splenic function after splenectomy.     

Auranofin inhibits the induction of interleukin 1 beta and tumor necrosis factor alpha mRNA in macrophages

Gold compounds are widely used in the treatment of rheumatoid arthritis, but their mechanisms of action remain unclear. We demonstrate here that auranofin (AF) (0.1-3 microM), but neither the hydrophilic gold compounds aurothiomalate (ATM) and aurothioglucose nor methotrexate or D-penicillamine, inhibits the induction of interleukin 1 beta and tumor necrosis factor (TNF) alpha mRNA and protein by either zymosan, lipopolysaccharide (LPS), or various bacteria in mouse macrophages. The auranofin-mediated inhibition of the induction of TNF-alpha mRNA was stronger than that of interleukin (IL) 1 beta mRNA. AF, but not the other drugs, also inhibited zymosan-induced mobilization of arachidonate. The fact that AF inhibited the induction of mRNA for both these proinflammatory cytokines, irrespective of which stimulus was used, may indicate that it affects some common signal transduction step vital to their induction.     

Acetazolamide treatment prevents in vitro endotoxin-stimulated tumor necrosis factor release in mouse macrophages

A 22-year-old woman was admitted to our hospital with fever, generalized lymphadenopathy, and pancytopenia in February 1995. She was diagnosed as having systemic lupus erythematosus (SLE) based on positivity for anti-nuclear antibody, and polyarthritis among other findings. A diagnosis of disseminated intravascular coagulation (DIC) was made based on the increase of FDP and other data (DIC score: 7). We also detected an anti-fibrinogen antibody. Lymph node biopsy revealed subacute necrotizing inflammation and there were on signs of the hemophagocytic phenomenon in bone marrow. The DIC score improved and the anti-fibrinogen antibody disappeared in association with the response of SLE to prednisolone therapy. The onset of SLE associated with DIC has never been reported before, as far as we could determine. The mechanism of DIC associated with SLE may be related to endothelial damage caused by immune complexes.     

Regulation of nitric oxide production by rat alveolar macrophages in response to silica exposure

Research conducted primarily over the past 5-8 years on the psychosocial effects of pediatric chronic physical disorders on children and their families is reviewed. A large body of studies show that both children and their mothers, as groups, are at increased risk for psychosocial adjustment problems compared to peers, but that there is considerable individual variation in outcome. Since the last review on this topic (Eiser, 1990a), many studies have been conducted to identify risk and resistance factors associated with differences in adjustment among these children and their mothers. Improvements are noted in the theoretical basis for this work, programmatic nature of some of the research, and efforts at producing clinically relevant information. Evaluations of interventions, however, are lagging. Critical issues and future directions regarding developmental approaches, theory, method, measurement, and intervention are discussed.     

The biphasic mRNA expression pattern of bovine interleukin-8 in Pasteurella haemolytica lipopolysaccharide-stimulated alveolar macrophages is primarily due to tumor necrosis factor alpha

Pasteurella haemolytica serotype 1 is the bacterial agent responsible for the pathophysiological events associated with bovine pneumonic pasteurellosis. Our previous studies support a role for the lipopolysaccharide (LPS) from P. haemolytica in the induction of proinflammatory cytokines. One of the pathological hallmarks of bovine pneumonic pasteurellosis is an influx of neutrophils into the alveolar spaces. This pronounced influx suggests the local production of a chemotactic factor(s) such as interleukin-8 (IL-8). In the context of the lung, the alveolar macrophage appears to be the major producer of IL-8, a proinflammatory cytokine with potent neutrophil chemotactic activity. By using Northern blot analysis, we have examined the kinetics of IL-8 mRNA expression in P. haemolytica LPS-stimulated bovine alveolar macrophages and found that 1 ng of LPS per ml induces maximal expression of IL-8 mRNA. The results also indicate a biphasic time course expression pattern in which IL-8 mRNA levels peak between 1 and 2 h in the first phase and between 16 and 24 h in the second phase (P < 0.01). In addition, monospecific polyclonal antibodies were used to demonstrate the role of tumor necrosis factor alpha (TNF-alpha) in the second phase of IL-8 mRNA expression. Our findings support a role for P. haemolytica LPS and TNF-alpha in the induction of IL-8 from bovine alveolar macrophages.