摘要:

Industrial air pollutants from Upper Silesia Poland contain over 250 polycyclic and hetero cyclic aromatic hydrocarbons and heavy metals including mutagenic and carcinogenic chemicals that have been shown to form DNA adducts Over 4 million habitants of Silesia are permanently exposed to the industrial pollution by pulmonary and dermal routes and by contaminated food and water These chemicals when examined separately in animals models were proven immunotoxic We studied the extrapulmonary immunotoxic potential of a typical mixture of Silesian filter suspended matter from a selected area over a specific season and time period Early changes in the immune system were analyzed in BALB c mice exposed ip to acute doses of 20 330 mg dust mixture kg body weight 0 06 1 0 LD50 No major changes were noted for weight and the cellularity of spleen liver and kidneys However dramatic decrease in thymus weight index and thymocyte cell count were noted as early as 24 72 h postexposure which correlated with almost complete depletion of immature double positive CD4 CD8 thymocytes Changes in spleen were less profound however increased depletion of B cells over T cells was noted at high doses of the suspended matter Exposure to the airborne dust also decreased cytokine production by spleen cells such as interferon IFN and tumor necrosis factor TNF Overall a single exposure to Silesian dust even at the relatively low 0 06 LD50 dose affected lym phokine production suppressed B cell proliferative response and depleted thymuses of immature double positive CD4 CD8 cells A chemical synergism is suspected To our knowledge none of the known components of Silesian suspended matter when examined as a single chemical was shown to exert such a profound biological effect

ISSN:0098-4108    

DOI:10.1080/009841096160628

出版商:Informa UK Ltd    

年代:1996

数据来源: Taylor

摘要:

The object of this study was to assess the relationship between occupational Portland cement dust exposure and respiratory health Respiratory symptoms and ventilatory func tion were studied in a group of 591 male Portland cement workers employed in four cement plants The prevalence of chronic respiratory symptoms was higher in exposed than in control workers The exposed group had a significantly lower mean forced vital capacity FVC forced expiratory volume at 1 s FEV1 and forced expiratory flows after exhalation of 50 and 75 of the vital capacity FEF50 FEF75 than the control group The data suggest that occupational exposure to Portland cement dust may lead to higher prevalence of chronic respiratory symptoms and the reduction of ventilatory capacity

ISSN:0098-4108    

DOI:10.1080/009841096160637

出版商:Informa UK Ltd    

年代:1996

数据来源: Taylor

摘要:

Extensive literature exists supporting the accumulation of organochlorine pesticides such as DDT 2 2 bis p chlorophenyl 1 1 1 trichloroethane and polychlorinated biphenyls PCBs in human adipose tissue Debate has surfaced concerning the link between these environmental contaminants and human breast cancer Accurate residue analysis and proper analytical procedures are critical in determining the extent to which these com pounds play a role in human breast cancer Further adequate quality assessment quality control QA QC is critical for reliable residue analysis The purpose of this research was twofold 1 to find an appropriate surrogate for human breast adipose tissue for spiking purposes as human samples are difficult to obtain and 2 to develop a human breast adipose tissue pool that yields adequate reproducibility with low coefficients of variation CVs for each compound of interest Using a previously validated method developed in the Analytical Laboratory at Colorado State University rendered ovine adipose tissue was found to be a suitable spiking material as it was free of interfering compounds and behaved in a manner similar to human breast adipose tissue throughout the analytical method Further this analytical method was used to produce data on three control pool preparations A blended human breast adipose tissue n 26 B blended and partially rendered human breast adipose tissue n 12 and C fully blended and rendered human breast adipose tissue n 15 The CVs between control pools vary up to 20 for a single compound The most reproducible preparation procedure requires full blend ing and rendering

ISSN:0098-4108    

DOI:10.1080/009841096160646

出版商:Informa UK Ltd    

年代:1996

数据来源: Taylor

摘要:

Although the pathogenic mechanisms underlying silica induced lung damage are well described few studies have examined the expression and role of adhesion molecules in lung injury induced by this particle Here we report that intratracheal instillation of silica crystals quartz SI into the lungs of C57Bl 6 mice results in a significant increase in levels of intercellular adhesion molecule 1 ICAM 1 in lung tissue and in lung lavage fluid This increased expression of ICAM 1 appeared to be associated with later 24 h cell influx and lung injury rather than in the initiation of these events Exposure of mice to the nontoxic particle titanium dioxide did not elicit increased expression of ICAM 1 in lung tissue or lavage fluid Passive administration of rat anti mouse ICAM 1 monoclonal antibody significantly decreased the influx of neutrophils PMNs into the alveoli and the levels of lung tissue ICAM 1 and yet had no effect on measures of lung injury or increased collagen deposition These data suggest that increased ICAM 1 expression in lung tissue following exposure to silica plays a partial role in the trafficking of neutrophils into the airways

ISSN:0098-4108    

DOI:10.1080/009841096160655

出版商:Informa UK Ltd    

年代:1996

数据来源: Taylor

摘要:

Upper respiratory tract viral infections have been reported in clinical studies to serve as risk factors for allergic sensitization In order to study the relationship linking influenza virus illnesses to development of allergy murine models of allergen sensitization were pre viously employed These models showed that lethal influenza viruses were able to trigger allergen specific immunoglobulin E IgE production and to inhibit tolerance to repeated exposure to aerosolized allergen in the mouse The disadvantage of these murine models consists in the utilization of virulant and lethal strains of influenza virus A nonlethal rat adapted influenza virus RAIV host resistance model has been developed in our labora tory It was used to evaluate the effect of influenza virus infection on IgE responses to inhaled ovalbumin OA in the rat The high IgE responder Brown Norway BN rat was chosen for further study after comparing the IgE response to OA in Fischer 344 F344 and BN rats On d 1 BN rats were sensitized by administration of 1 mg OA subcuta neously alone or together with aluminum hydroxide 200 mg and Bordetella pertussis 9 15 10 killed bacilli per rat in 1 ml or only received saline Rats were either infected with RAIV or sham infected on d 0 24 h prior to sensitization or on d 15 17 or 57 Rats were exposed for 3 min to aerosolized OA OA 3 in phosphate buffered saline EFFECT OF INFLUENZA VIRUS INFECTION ON OVALBUMIN SPECIFIC IgE RESPONSES TO INHALED ANTIGEN IN THE RAT Herv Lebrec U S Environmental Protection Agency Health Effects Research Laboratory Research Triangle Park North Carolina USA

ISSN:0098-4108    

DOI:10.1080/009841096160664

出版商:Informa UK Ltd    

年代:1996

数据来源: Taylor

摘要:

The molecular basis of the immunotoxic effect of ammonium metavanadate on signal transduction involved in macrophage activation was studied in resident peritoneal macrophages PEM and a murine macrophage like cell line J774 A fourfold elevation in cytosolic free calcium levels was observed within 10 s following lipopolysaccharide LPS stimulation of the non vanadate exposed controls both in vitro and in vivo the levels returned to prestimulation values within 70 s Exposure to phorbol ester PMA did not result in any appreciable change in cytosolic free calcium levels Compared to untreated controls treatment with vanadate caused a significant elevation in basal cytosolic calcium levels Such elevation was not enhanced further by LPS LPS stimulation of macrophages also resulted in a significant elevation of membrane associated protein kinase C PKC activity which was however inhibited in a dose dependent manner by vanadate in both in vitro and in vivo studies Exposure to PMA also resulted in a significant elevation of membrane associated PKC activity vanadate treatment at lower levels did not cause downregulation indicating that vanadate at these levels interfered with the receptor medi ated events rather than the enzyme directly Vanadate at higher exposure levels inhibited the activity even in PMA stimulated macrophages No significant difference occurred in cytosolic PKC activities in control macrophages vanadate treatment at lower levels resulted in a significant elevation of cytosolic PKC activities following stimulation with LPS or PMA indicating that vanadate might be interfering with the translocation process

ISSN:0098-4108    

DOI:10.1080/009841096160673

出版商:Informa UK Ltd    

年代:1996

数据来源: Taylor