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PubMed1975

Studies on the mucosa of postmenopausal oviducts: surface appearance, ciliary activity, and the effect of estrogen treatment.

The epithelial lining of the human oviduct is known to be responsive to the fluctuating hormonal levels of the normal menstrual cycle, but its response to the changes in hormonal climate at the time of the menopause is not clearly defined. In this study the oviducts of nine postmenopausal patients were obtained at the time of abdominal hysterectomy, and the lining epithelium was studied by scanning electron microscopy. The activity of cilia on the fresh tissue was assessed by their ability to transport particulate matter applied to the epithelial surface. The fimbriae of oviducts from women who had received little or no estrogen treatment before surgery showed a significant deciliation of the epithelium, compared with specimens from premenopausal patients, and even showed some sloughing of cells from the surface. The secretory cells appeared inactive. However, the specimens from patients who had been treated with estrogen for periods of 1 year or more showed a remarkable maintenance of the epithelium, with the proportion of ciliated cells remaining almost as high as in premenopausal oviducts, even as late as 25 years after the menopause. The ampullar and isthmic portions showed less obvious changes. Cilia in oviducts from the former group (short-term or no treatment) were incapable of transporting 15-mum microspheres or lycopodium spores applied to the epithelial surface, whereas the oviductal cilia obtained from patients under long-term estrogen therapy showed efficient transport of particulate matter. The results are discussed in relation to earlier conflicting reports on the postmenopausal oviduct.

Adult↗

PubMed2005

Dependence of urban air pollutants on meteorology.

Dependence of air pollutants on meteorology is presented with the aim of understanding the governing processes pollutants phase interaction. Intensive measurements of particulate matter (PM10) and gaseous materials (e.g., CO, NO2, SO2, and O3) are carried out regularly in 2002 at 14 measurement sites distributed over the whole territory of Great Cairo by the Egyptian Environmental Affairs Agency to assess the characteristics of air pollutants. The discussions in this work are based upon measurements performed at Abbassiya site as a case study. The nature of the contributing sources has been investigated and some attempts have been made to indicate the role played by neighboring regions in determining the air quality at the site mentioned. The results hint that, wind direction was found to have an influence not only on pollutant concentrations but also on the correlation between pollutants. As expected, the pollutants associated with traffic were at highest ambient concentration levels when wind speed was low. At higher wind speeds, dust and sand from the surrounding desert was entrained by the wind, thus contributing to ambient particulate matter levels. We also found that, the highest average concentration for NO2 and O3 occurred at humidity<or=40% indicative for strong vertical mixing. For CO, SO2 and PM10 the highest average concentrations occurred at humidity above 80%.

Aerosols↗

PubMed2005

Variations of the particulate carbon distribution from a nonroad diesel generator.

The emissions of diesel particulate matter (DPM) from diesel engines are causing increasing health concerns due to their suspected carcinogenicity, especially the carbonaceous fractions. The total DPM emissions and the organic and elemental carbon (OC and EC) distributions of the DPM depend on many operating factors, such as load, engine design parameters, fuel sulfur content, fuel usage rate, and sampling conditions. Results of previous studies on the OC/EC variations with load for heavy-duty vehicles have been reported, but information is scarce for nonroad diesel generators. There is a clear need to better characterize nonroad DPM emissions, as studies have indicated that DPM emissions from nonroad diesel engines are significantly higher than those from on-road sources. The objective of the study is to provide a detailed account of the OC/EC distributions for a nonroad diesel generator operated with high and low sulfur fuels under different load conditions. DPM emissions were collected using an EPA Method 5 (Determination of Particulate Matter Emissions from Stationary Sources) sampling train. The OC and EC concentrations were quantified by NIOSH Method 5040. DPM concentrations and the relative contributions of OC, EC, and noncarbonaceous materials vary significantly with engine load, fuel sulfur content, and sample collection temperature. The fractions of EC over DPM increase with increasing load from 21% at OkW to 84% at 75 kW for the low sulfur fuel, while those of OC decrease from 62% to 9%. This is consistent with other studies, and the same trends exist regardless of the sulfur content and DPM collection temperature. The fractions of organic compounds range from 77% to 19% for the high sulfur fuel. Noncarbonaceous materials are from 27% to 18% in fraction from high sulfur DPM as opposed to the 17% to 7% in the low sulfur diesel emissions. At lower collection temperatures, more OC and noncarbonaceous materials are observed.

Air Pollutants↗

PubMed2005

2002 summer fires in Lithuania: impact on the Vilnius city air quality and the inhabitants health.

The episodes with highly elevated concentrations of particulate matter (PM10), NOx, and CO were detected in the city of Vilnius between August and September 2002 and possible reasons were analysed. This increase was attributed to emissions from fires in the vicinity of the city of Vilnius when data on fire location and start, wind direction and concentrations of pollutants were analysed. The correlation coefficient between PM10 and CO, NO, NO2, NOx increased during the fire period in comparison with the same correlation after the fire period. During the fire episodes, there was an increase in concentration of ozone precursors, and meteorological conditions were favourable for photochemical reactions. Therefore, the hourly values for ozone exceeded the values common for Vilnius. Generally, during the episodes, the maximum of NO2 concentrations was 2 times higher than the limit value for NO2 laid down in the Council Directives 1999/30/EC [Council Directive 1999/30/EC of 22 April 1999 relating to limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead in ambient air. Official Journal L 163, 29/06/1999: 0041-0060], and that of PM10 was even 5.5 times higher than the limit value for PM10. Human health effects study in Vilnius indicated that the incidents of documented respiratory diseases and exacerbation of the bronchial asthma during the fire period were up to 20 times higher in comparison to periods with no fires.

Air Pollutants↗

PubMed2002

In vivo ingestion of heavy metal particles of Se, Hg and W by murine macrophages. A study using scanning electron microscopy coupled with X-ray microanalysis.

Several heavy metals that are currently employed in industry may become polluters of work and natural environments. As particulate matter, heavy metals are suitable for entering the human body through the respiratory and digestive systems. They often end up inside phagocytes; the size of the microscopic particles modulates both their phagocytosis, and the physiology of macrophages. Here we have adopted an experimental model to investigate the ingestion of particles of three industrial heavy metals (Se, Hg, W) by murine peritoneal macrophages in vivo. The phagocytes were studied by scanning electron microscopy coupled with X-ray elemental microanalysis (SEM-XRM), a method that allows specific identification of Se, W and Hg in cells at high resolution. We found that Hg that was taken up by macrophages was organized into small, round particles (0.31 +/- 0.14 microm). This was in contrast with the larger size of intracellular particles of Se (2.37 +/- 1.84 microm) or W (1.75 +/- 1.34 microm). Ingested particles of Se and W, but not Hg, often caused bulging of the cell surface of macrophages. We conclude that particulate matters of Se, W and Hg are organized in particles of different size inside macrophages. This size difference is likely to be associated with distinct phlogistic activities of these heavy metals, Se and W causing a milder inflammatory reaction than Hg.

Animals↗

PubMed2002

Characterisation of airborne particles collected within and proximal to an opencast coalmine: South Wales, U.K.

Airborne particulate matter has been collected from within, and proximal to, an opencast coal mine in south Wales. This work forms the first part of a three year project to collect and characterise, then determine the possible toxicology of airborne particles in the south Wales region. High-resolution Field Emission SEM has shown that the coal mine dusts consist largely of an assemblage of mineral grains and vehicle exhaust particles. SEM-EDX has shown that the mineralogical make-up of the PM10 is complex, heterogeneous, and constantly changing. These findings are supported by analytical TEM-EPXMA. However, patterns can be determined relating the mineralogical composition of the airborne particles to collection locations and mining activities within the opencast. At our study opencast, Park Slip West, quartz, which has known health effects, never exceeded 30% of the total collection mass, and average levels were much less. Vehicle exhaust emissions was the largest source in terms of particle numbers. The mass of airborne particulate matter within the pit averaged approximately twice that of outside the pit: importantly however, this higher mass was due to relatively large, and non-respirable, mineral grains. This study demonstrates that the physicochemical and mineralogical characterisation of airborne particles from mining and quarrying is essential to quantify the respirable fraction, and to identify potentially hazardous components within the PM10.

Air Pollutants↗

PubMed2005

Relationships of Indoor, Outdoor, and Personal Air (RIOPA). Part I. Collection methods and descriptive analyses.

This study on the relationships of indoor, outdoor, and personal air (RIOPA) was undertaken to collect data for use in evaluating the contribution of outdoor sources of air toxics and particulate matter (PM) to personal exposure. The study was not designed to obtain a population-based sample, but rather to provide matched indoor, outdoor, and personal concentrations in homes that varied in their proximity to outdoor pollution sources and had a wide range of air exchange rates (AERs). This design allowed examination of relations among indoor, outdoor, and personal concentrations of air toxics and PM across a wide range of environmental conditions; the resulting data set obtained for a wide range of environmental pollutants and AERs can be used to evaluate exposure models. Approximately 100 households with residents who do not smoke participated in each of three cities in distinct locations expected to have different climates and housing characteristics: Elizabeth, New Jersey; Houston, Texas; and Los Angeles County, California. Questionnaires were administered to characterize homes, neighborhoods, and personal activities that might affect exposures. The concentrations of a suite of volatile organic compounds (VOCs) and carbonyl compounds, as well as the fraction of airborne particulate matter with a mass median aerodynamic diameter < or = 2.5 microm (PM2.5), were measured during continuous 48-hour sessions in which indoor, outdoor, and personal air samples were collected simultaneously. During the same 48-hour period, the AER (exchanges/hr; x hr(-1)) was determined in each home, and carbonyl compounds were measured inside vehicle cabins driven by a subset of the participants. In most of the homes, measurements were made twice, during two different seasons, to obtain a wide distribution of AERs. This report presents in detail the data collection methods, quality control measures, and initial analyses of data distributions and relations among indoor, outdoor, and personal concentrations. The results show that indoor sources dominated personal and indoor air concentrations of many measured VOCs and carbonyl compounds. For several measured species, personal concentrations were higher than either indoor or outdoor concentrations, indicating the presence of some sources closely related to personal activities. For some species there were no significant indoor sources in the majority of the homes; thus indoor concentrations were mainly determined by outdoor concentrations in these homes. The range of distributions of air concentrations for the measured VOCs, formaldehyde and acetaldehyde, PM2.5, and AERs were generally consistent with values reported previously in the literature. Thus associations derived from or models based on this data set that may link the influence of outdoor sources with indoor air concentrations of air toxics and PM2.5 can be relevant to other urban settings. The simultaneous measurements of indoor concentrations, outdoor concentrations, AERs, and room volumes allowed the use of a mass balance model, under the steady-state approximation, to mechanistically examine the relative contributions of indoor and outdoor sources to measured indoor concentrations on a home-by-home basis. Estimated indoor source strengths for VOCs and carbonyl compounds varied widely from home to home, consistent with the indoor-outdoor concentration patterns, as shown in scatter plots. The indoor source estimations agreed with published values for PM2.5 and with the general understanding of sources of VOCs and carbonyl compounds. The source strengths reported here, derived from hundreds of homes, are an important contribution to the literature on exposure to air toxics. For the first time for many compounds, these estimates present a cohesive set of measurements across a range of air toxics in paired indoor, outdoor, and personal samples along with AER and questionnaire results that can be used for future analyses of indoor air quality. The estimation of outdoor contributions to measured indoor concentrations provides insights about the relative importance of indoor and outdoor sources in determining indoor concentrations, the main determinant of personal exposure for most of the measured compounds. In this report simple statistical tests mainly of the pooled data were used to analyze differences by sampling site, emission source type, season, home type, and home age. Paired adult-child personal concentrations within the same home were also compared using the pooled data set. These analyses generated some intriguing results that warrant more in-depth investigation in the future.

Air Movements↗

PubMed1995

Air pollution and upper respiratory symptoms in children from East Germany.

Whereas evidence of adverse effects of air pollution on lower respiratory tract illnesses in children is increasing, little is known about the effects of high and moderate levels of air pollution on the incidence of upper respiratory illnesses. 9 to 11 year old schoolchildren (n = 1,854) living in Leipzig, East Germany were studied. The presence of upper respiratory symptoms was documented by a physician. Daily mean and maximum concentrations of SO2, particulate matter (PM) and NOx, as well as temperature and humidity, were measured. Furthermore, a self-administered questionnaire was distributed to the parents to assess confounding factors. Parents of 1,500 (81%) children returned the questionnaire. When controlling for paternal education, passive smoke exposure, number of siblings, temperature and humidity, increased risks for the development of upper respiratory symptoms were found in the winter months for SO2 mean concentrations (odds ratio (OR) = 1.72; 95% confidence interval (95% CI) 1.19-2.49). NOx mean concentrations (OR = 1.53; 95% CI 1.01-2.31) and PM maximum values (OR = 1.62; 95% CI 1.08-2.45). In the summer months, only NOx mean concentrations were associated with a significantly increased risk (OR = 1.82; 95% CI 1.21-2.73). A combination of high mean levels of different pollutants resulted in the highest risk (OR = 2.10; 95% CI 1.30-3.37 in the winter, and OR = 2.16; 95% CI 1.23-3.81 in the summer). We conclude that high concentrations of SO2, and moderate levels of particulate matters and NOx are associated with an increased risk of developing upper respiratory symptoms in childhood.(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollutants↗

PubMed2004

Indoor particle dynamics.

UNLABELLED: Airborne particulate matter is a diverse pollutant class whose excessive presence in indoor air contributes to an array of adverse health and material-damage effects. Particles are classified according to their diameter into three size modes: ultrafine (0.1 microm), accumulation (0.1-2 microm), and coarse (= 2 microm). These modes have largely distinct sources and composition, and they exhibit different dynamic behaviors. The concept of mass conservation or material balance provides a foundation for quantitatively and mechanistically linking important outcome variables, such as concentrations and exposures, to the influencing input parameters. The factors governing indoor particle concentrations include direct emissions from indoor sources, ventilation supply from outdoor air, filtration, deposition onto indoor surfaces, and removal from indoor air by means of ventilation. In some circumstances, transport and transformation processes within indoor environments may also play an important role in influencing particle concentrations and consequences. Such processes include mixing, interzonal transport, resuspension, coagulation, and phase change. PRACTICAL IMPLICATIONS: The paper gives a practical overview of issues related to particulate matter indoors, as well as valuable information for understanding filtration and how particles contribute to adverse health effects.

Air Movements↗

PubMed1994

Ambient air pollutants in upper Silesia: partial chemical composition and biological activity.

The air monitoring system in Upper Silesia has provided abundant data on airborne pollutants. Air quality in this region is bad: a concentration of several gases, volatile compounds, metals, and complex mixtures of organic compounds carried by small particulate matter exceeds both daily and yearly admissible levels. About 250 individual polycyclic aromatic hydrocarbonds (PAHs) were identified in airborne pollutants, and hundreds of not identified compounds are seen on gas chromatographic profiles as minor peaks. Among PAHs are present compounds with known carcinogenic potency for humans. Seasonal variation with distinctly lower concentration of pollutants in summer than in winter was noticed. Fifteen PAHs including benzo[a]pyrene (B[a]P) determined by GC-MS method in 20 measuring points showed constant relative proportions. Thus B[a]P could be used as a representative compound for other PAHs. In urban areas, a core of Silesia values for B[a]P concentration ranged from 60 to 90 ng/m3 in winter to 5 to 20 micrograms/m in summer. Mutagenicity tested on Salmonella strains showed seasonal variation with distinctly higher values in winter. Environmentally exposed humans showed a higher level of PAH-DNA adducts in WBC than the control population from rural area. Total organic extract of small particulate matter exhibited both direct and indirect mutagenic activity, induced formation of micronuclei in bone marrow cells of BALB/c mice, induced chromosomal rearrangements, and increased sister chromatid exchange index.

Air Pollutants↗

PubMedDate not supplied

Air pollution, aeroallergens and cardiorespiratory emergency department visits in Saint John, Canada.

Existing studies of the association between air pollution, aeroallergens and emergency department (ED) visits have generally examined the effects of a few pollutants or aeroallergens on individual conditions such as asthma or chronic obstructive pulmonary disease. In this study, we considered a wide variety of respiratory and cardiac conditions and an extensive set of pollutants and aeroallergens, and utilized prospectively collected information on possible effect modifiers which would not normally be available from purely administrative data. The association between air pollution, aeroallergens and cardiorespiratory ED visits (n = 19,821) was examined for the period 1992 to 1996 using generalized additive models. ED visit, air pollution and aeroallergen time series were prefiltered using LOESS smoothers to minimize temporal confounding, and a parsimonious model was constructed to control for confounding by weather and day of week. Multipollutant and multi-aeroallergen models were constructed using stepwise procedures and sensitivity analyses were conducted by season, diagnosis, and selected individual characteristics or effect modifiers. In single-pollutant models, positive effects of all pollutants but NO2 and COH were observed on asthma visits, and positive effects on all respiratory diagnosis groups were observed for O3, SO2, PM10, PM2.5, and SO4(2-). Among cardiac conditions, only dysrhythmia visits were positively associated with all measures of particulate matter. In the final year-round multipollutant models, a 20.9% increase in cardiac ED visits was attributed to the combination of O3 (16.0%, 95% CI 2.8-30.9) and SO2 (4.9%, 95%CI 1.7-8.2) at the mean concentration of each pollutant. In the final multipollutant model for respiratory visits, O3 accounted for 3.9% of visits (95% CI 0.8-7.2), and SO2 for 3.7% (95% CI 1.5-6.0), whereas a weak, negative association was observed with NO2. In multi-aeroallergen models of warm season asthma ED visits, Ascomycetes, Alternaria and small round fungal spores accounted for 4.5% (95% CI 1.8-7.4), 4.7% (95% CI 1.0-8.6) and 3.0% (95% CI 0.8-5.1), respectively, of visits at their mean concentrations, and these effects were not sensitive to adjustment for air pollution effects. In conclusion, we observed a significant influence of the air pollution mix on cardiac and respiratory ED visits. Although in single-pollutant models, positive associations were noted between ED visits and some measures of particulate matter, in multipollutant models, pollutant gases, particularly ozone, exhibited more consistent effects. Aeroallergens were also significantly associated with warm season asthma ED visits.

Air Pollutants↗

PubMed1983

[Biological effect of smog extract. VII. Severe disorders of the cell cycle and its phases in kidney cultures as effected by extract and fractions of smog from a heavily industrialized area].

We analyzed the effect of airborne particulate matter, collected from the city of Duisburg on DNA-synthesis, mitotic rate and the cell cycle employing mammalian cells in vitro. As a test system we used logarithmically growing kidney cell cultures of the Syrian golden hamster (Cricetus aureatus). To elucidate alterations of DNA-synthesis and cell cycle under influence of extracts and fractions of city smog we used the autoradiographic method and the analytic procedure according to Quastler and Sherman. Extract and fractions induced a dose dependent decrease of DNA synthesizing cells, reduction of mitotic rate and very strong alterations of the cell cycle. The particular phases of the cell cycle were extended, partly abolished. We observed great differences concerning the effect of various fractions. The strongest effect was exerted by the total extract and the methanol-fraction. In this case the effective dosage was equivalent to an air volume of 2-5 cbm. With a declining sequence of toxicity followed the fractions of cyclohexane, propanol and of polyaromates. Results demonstrate that airborne particulate matter or city smog from industrialized areas contain substances which act strongly cytotoxic on mammalian cells in vitro and induce heavy alterations of the cell cycle. Therefore we have to expect, especially after long-term exposure also in human being health damages.

1-Propanol↗

PubMed1981

Sampling and analysis of airborne residues of paraquat in treated cotton field environments.

A method was developed for the analysis of paraquat residues in airborne particulate matter collected by filtration or impaction. The method is based on extraction of paraquat with 6N hydrochloric acid, transfer of residue to saturated ammonium bicarbonate solution, and reduction of the resulting residue with alkaline sodium borohydride to a mixture of two tertiary amines with subsequent determination by nitrogen-selective gas chromatography (GLC). Recoveries ranged from 74 to 96% for filters spiked at 0.05 microgram and above; the limit of detection is approximately 0.5 ng/m3 for high volume air samples. Paraquat concentrations measured in the air downwind from two commercial applications to cotton during spraying fell regularly from extrapolated interval-average values of 4.31 and 10.7 microgram/m3 at the 1 m downwind edge of the two fields to less than 50 ng/m3 at approximately 400 m downwind. Downwind samples taken 2 to 4 hr after spraying contained 1 to 10% as much paraquat as those during spraying, and by 5 to 7 hr no paraquat was detectable in the downwind air. Paraquat was also found in the airborne particulate matter during mechanical harvesting of one of the fields, the maximum interval-average values being 1,245 and 516 ng/m3 just outside and inside an open cab, respectively. The analytical findings for paraquat are compared with those for S,S,S-tributylphosphorotrithioate (DEF), a component of the harvest aid mixture employed, and discussed in terms of occupational exposure, potential hazard, and recommended occupational practices.

Air Pollutants↗

PubMed2000

Cytotoxic and mutagenic effects, particle size and concentration analysis of diesel engine emissions using biodiesel and petrol diesel as fuel.

Diesel engine exhaust particles (DEP) contribute substantially to ambient air pollution. They cause acute and chronic adverse health effects in humans. Biodiesel (rapeseed oil methyl ester. RME) is used as a "green fuel" in several countries. For a preliminary assessment of environmental and health effects of RME, the particulate-associated emissions from the DEP of RME and common fossil diesel fuel (DF) and their in vitro cytotoxic and mutagenic effects were compared. A test tractor was fuelled with RME and DF and driven in a European standard test cycle (ECE R49) on an engine dynamometer. Particle numbers and size distributions of the exhausts were determined at the load modes "idling" and "rated power". Filter-sampled particles were extracted and their cytotoxic properties tested using the neutral red assay. Mutagenicity was tested using the Salmonella typhimurium/microsome assay. Despite higher total particle emissions, solid particulate matter (soot) in the emissions from RME was lower than in the emissions from DF. While the size distributions and the numbers of emitted particles at "rated power" were nearly identical for the two fuels, at "idling" DF emitted substantially higher numbers of smaller particles than RME. The RME extracts caused fourfold stronger toxic effects on mouse fibroblasts at "idling" but not at "rated power" than DF extracts. The extracts at both load modes were significantly mutagenic in TA98 and TA100. However, extracts of DF showed a fourfold higher mutagenic effect in TA98 (and twofold in TA100) than extracts of RME. These results indicate benefits as well as disadvantages for humans and the environment from the use of RME as a fuel for tractors. The lower mutagenic potency of DEP from RME compared to DEP from DF is probably due to lower emissions of polycyclic aromatic compounds. The higher toxicity is probably caused by carbonyl compounds and unburned fuel, and reduces the benefits of the lower emissions of solid particulate matter and mutagens from RME.

Animals↗

PubMed1993

Particulate air pollution and hospital emergency room visits for asthma in Seattle.

Recent studies have associated short-term exposure to respirable particulate matter (PM10) exposure with peak flow decrements, increased symptoms of respiratory irritation, increased use of asthma medications, and increased hospitalization for asthma. Increased mortality from chronic respiratory disease has also been reported. To help confirm whether PM10 exposure is a risk factor for the exacerbation of asthma, we compiled daily records of asthma emergency room visits from eight hospitals in the Seattle area. In Poisson regressions controlling for weather, season, time trends, age, hospital, and day of the week, the daily counts of emergency room visits for persons under age 65 were significantly associated with PM10 exposure on the previous day. The mean of the previous 4 days' PM10 was a better predictor (p < 0.005). The relative risk for a 30 micrograms/m3 increase in PM10 was 1.12 (95% confidence interval 1.20 to 1.04). Daily PM10 concentrations never exceeded 70% of the current ambient air quality standards during the period. The consistency of investigations of the health effects of PM10 suggest that increased attention should be given to the control of particulate matter air pollution.

Adolescent↗

PubMed2002

Iron-binding and storage proteins in sputum.

Induced sputum (IS) and bronchoalveolar lavage (BAL) sample different lung compartments, with IS obtaining secretions from the surfaces of the bronchial airways and BAL sampling secretions from the alveolar airspaces. Deposition of iron-containing particulate matter occurs preferentially in the bronchial airways compared to the distal airspaces. Iron-binding and storage proteins have been measured in BAL in healthy humans, where they act to sequester and detoxify available iron; however, their comparative levels in the airways are not well defined. Seventeen (n = 17) healthy, nonsmoking volunteers underwent sputum induction and fiber-optic bronchoscopy with lavage in order to measure and compare the levels of iron and iron-binding and storage proteins in BAL, bronchial lavage (BL), and IS. Relative to BAL and BL specimens, concentrations of total iron, ferritin, lactoferrin, and total iron binding capacity (TIBC) were significantly increased and transferrin decreased in IS. Immunohistochemical staining showed increased ferritin, lactoferrin, and TIBC in IS. Constitutive levels of iron and iron-binding and storage proteins (except for transferrin) are in greatest concentration in the bronchial airways relative to the alveolar airspaces in healthy humans. We speculate that these proteins reflect activated antioxidant defense mechanisms resulting from the preferential deposition of iron-containing particulate matter in the airways. The finding of decreased transferrin with increased ferritin suggests a local cellular response via iron-response elements (IRE) associated with the mRNAs for these two iron-binding proteins.

Adolescent↗

PubMed2005

Nanoparticle-induced platelet aggregation and vascular thrombosis.

Ever increasing use of engineered carbon nanoparticles in nanopharmacology for selective imaging, sensor or drug delivery systems has increased the potential for blood platelet-nanoparticle interactions. We studied the effects of engineered and combustion-derived carbon nanoparticles on human platelet aggregation in vitro and rat vascular thrombosis in vivo. Multiplewall (MWNT), singlewall (SWNT) nanotubes, C60 fullerenes (C60CS) and mixed carbon nanoparticles (MCN) (0.2-300 microg ml(-1)) were investigated. Nanoparticles were compared with standard urban particulate matter (SRM1648, average size 1.4 microm). Platelet function was studied using lumi aggregometry, phase-contrast, immunofluorescence and transmission electron microscopy, flow cytometry, zymography and pharmacological inhibitors of platelet aggregation. Vascular thrombosis was induced by ferric chloride and the rate of thrombosis was measured, in the presence of carbon particles, with an ultrasonic flow probe. Carbon particles, except C60CS, stimulated platelet aggregation (MCN>or=SWNT>MWNT>SRM1648) and accelerated the rate of vascular thrombosis in rat carotid arteries with a similar rank order of efficacy. All particles resulted in upregulation of GPIIb/IIIa in platelets. In contrast, particles differentially affected the release of platelet granules, as well as the activity of thromboxane-, ADP, matrix metalloproteinase- and protein kinase C-dependent pathways of aggregation. Furthermore, particle-induced aggregation was inhibited by prostacyclin and S-nitroso-glutathione, but not by aspirin. Thus, some carbon nanoparticles and microparticles have the ability to activate platelets and enhance vascular thrombosis. These observations are of importance for the pharmacological use of carbon nanoparticles and pathology of urban particulate matter.

Animals↗

PubMed1996

Motility and other characteristics of human sperm can be measured by computer-assisted sperm analysis of samples stained with Hoechst 33342.

OBJECTIVE: To develop methods for using a DNA-specific dye to discriminate between motile and nonmotile sperm and static particulate matter in fresh and diluted semen, using computer-assisted sperm analysis (CASA) with the Hamilton Thorne IVOS, TOX version (Hamilton-Thorne Research, Beverly, MA). DESIGN: Donor semen was divided for treatment as fixed stained sperm (Hoechst 33342 stain; Sigma Chemical Company, St. Louis, MO), fresh motile and nonmotile stained sperm, and unstained control sperm. SETTING: Normal human volunteers in an academic research and medical environment. PATIENTS: Selected healthy student volunteers. INTERVENTIONS: Delivered semen to the laboratory within 1 hour of collection. MAIN OUTCOME MEASURE: Semen quality measured by CASA. RESULTS: Fixed or fresh human sperm stained with Hoechst 33342 dye should be diluted to < or = 50 x 10(6) sperm/mL to count sperm accurately. Motile and nonmotile sperm were stained suitably with 5 to 10 micrograms/mL of dye when diluted with a simple diluent, but the dye concentration should be increased to 40 micrograms/mL when egg yolk is in the diluent. CONCLUSIONS: The DNA-specific dye, Hoechst 33342, can be used to discriminate between motile and nonmotile sperm and other particulate matter when evaluated by CASA with instrumentation equipped with suitable optics.

Benzimidazoles↗