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PubMed1989

Prediction of relapse or survival in patients with node-negative breast cancer by DNA flow cytometry.

More accurate prediction of the prognosis in women with node-negative breast cancer may improve physicians' ability to identify the patients most likely to benefit from systematic adjuvant therapy. With this in mind, we performed DNA flow-cytometric measurements of ploidy and the fraction of cells in the synthesis phase of the cell cycle (S-phase fraction) on 395 specimens of node-negative breast cancer from our bank of frozen tumors, using the aliquots of pulverized frozen tissue from steroid-receptor assays. The median duration of follow-up in patients still alive at the time of analysis was 59 months. Thirty-two percent of the 345 specimens that could be evaluated were diploid, and 68 percent were aneuploid. The probability of disease-free survival at five years was 88 +/- 3 percent in patients with diploid tumors and 74 +/- 3 percent in those with aneuploid tumors (P = 0.02). The S-phase fraction was not a significant additional predictor of disease-free survival in patients with aneuploid tumors. However, the probability of disease-free survival in patients with diploid tumors and low S-phase fractions was 90 +/- 3 percent at five years, as compared with 70 +/- 13 percent in those with diploid tumors and high S-phase fractions (P = 0.007). Similar differences in overall survival were noted. We conclude that DNA flow-cytometric measurements of ploidy and S-phase fraction can be performed on frozen specimens of tumors and are potentially important predictors of disease-free and overall survival in patients with node-negative breast cancer.

Breast Neoplasms↗

PubMed2003

Minimum specific cost control of technological processes realized in a living objects-containing microenvironment.

The purpose of the present work is to work out an approach for the development of software and the choice of hardware structures when designing subsystems for automatic control of technological processes realized in living objects containing limited space (microenvironment). The subsystems for automatic control of the microenvironment (SACME) under development use the Devices for Air Prophylactic Treatment, Aeroionization, and Purification (DAPTAP) as execution units for increasing the level of safety and quality of agricultural raw material and foodstuffs, for reducing the losses of agricultural produce during storage and cultivation, as well as for intensifying the processes of activation of agricultural produce and industrial microorganisms. A set of interconnected SACMEs works within the framework of a general microenvironmental system (MES). In this research, the population of baker's yeast is chosen as a basic object of control under the industrial fed-batch cultivation in a bubbling bioreactor. This project is an example of a minimum cost automation approach. The microenvironment optimal control problem for baker's yeast cultivation is reduced from a profit maximum to the maximization of overall yield by the reason that the material flow-oriented specific cost correlates closely with the reciprocal value of the overall yield. Implementation of the project partially solves a local sustainability problem and supports a balance of microeconomical, microecological and microsocial systems within a technological subsystem realized in a microenvironment maintaining an optimal value of economical criterion (e.g. minimum material, flow-oriented specific cost) and ensuring: (a) economical growth (profit increase, raw material saving); (b) high security, safety and quality of agricultural raw material during storage process and of food produce during a technological process; elimination of the contact of gaseous harmful substances with a subproduct during various technological stages; (c) improvement of labour conditions for industrial personnel from an ecological point of view (positive effect of air aeroionization and purification on human organism promoting strengthened health and an increase in life duration, pulverent and gaseous chemical and biological impurity removal). An alternative aspect of a controlled living microenvironment forming is considered.

Agriculture↗

PubMed1971

Photocatalytic Production of Organic Compounds from CO and H(2)O in a Simulated Martian Atmosphere.

[(14)C]CO(2) and [(14)C]organic compounds are formed when a mixture of [(14)C]CO and water vapor diluted in [(12)C]CO(2) or N(2) is irradiated with ultraviolet light in the presence of soil or pulverized vycor substratum. The [(14)C]CO(2) is recoverable from the gas phase, the [(14)C]organic products from the substratum. Three organic products have been tentatively identified as formaldehyde, acetaldehyde, and glycolic acid. The relative yields of [(14)C]CO(2) and [(14)C]organics are wavelength- and surface-dependent. Conversion of CO to CO(2) occurs primarily at wavelengths shorter than 2000 A, apparently involves the photolysis of water, and is inhibited by increasing amounts of vycor substratum. Organic formation occurs over a broad spectral ranger below 3000 A and increases with increasing amounts of substratum. It is suggested that organic synthesis results from adsorption of CO and H(2)O on surfaces, with excitation of one or both molecules occurring at wavelengths longer than those absorbed by the free gases. This process may occur on Mars and may have been important on the primitive earth.

Journal Article↗

PubMed1982

Extracts from the brains of hibernating and alert ground squirrels: effects on cells in culture.

Aqueous extracts were prepared from pulverized, acetone-dehydrated brains of hibernating and alert ground squirrels. Addition of these extracts to Chinese hamster ovary cells in suspension culture resulted in a decrease in the amount of [3H]thymidine incorporated into acid-precipitable material without affecting the transport or phosphorylation of the nucleoside. The inhibition was time- and dose-dependent and full recovery occurred about 2 hr after exposure of the cells to the active extract. The active factor is readily oxidized during storage at -70 degrees C but full activity can be restored by treatment with 2-mercaptoethanol. The peptide nature of the active material is indicated by its susceptibility to proteases and by loss of activity after alkylation. Fasted or cold-acclimated rats also develop increased levels of active substance in their brains; however, brains of hibernating squirrels contain 10- to 50-fold more of the active substance than brains from either alert squirrels or rats. A time-dependent increase in activity of extracts from hibernating brain incubated with a homogenate from alert brain suggests that the peptide is activated or generated in the mixture.

Animals↗

PubMed2003

Different levels of TIMPs and MMPs in human lateral and medial rectus muscle tissue excised from strabismic patients.

PURPOSE: To arrive at an understanding of the differences in gene and protein expression between human lateral and medial rectus muscle tissue excised from strabismic patients. METHODS: Resected fragments of the lateral and medial rectus muscles obtained during strabismus surgery were frozen under liquid nitrogen and pulverized by a Freezer/Mill system. Radiolabelled cDNA was synthesized from polyA+ RNA and hybridized with a gene array nylon membrane (Atlas Human 1.2 Array) to detect the difference in gene expression between the lateral and medial rectus muscles. Based on the gene array results, tissue inhibitor of metalloproteinases (TIMP)-1 and 2, matrix metalloproteinase (MMP)-2, and bone morphogenetic protein (BMP)-4 were measured in solubilized muscle tissues by enzyme immunoassay and normalized by unit length of resection. RESULTS: The resected lateral rectus muscle had significantly smaller amounts of TIMP-1, TIMP-2 and BMP-4 but larger amounts of MMP-2 compared to the medial rectus muscle (P < 0.001, Mann-Whitney U test). The amounts of TIMP-1 in the muscle when the lateral and medial rectus were combined were positively correlated with TIMP-2 and BMP-4, while the amounts of TIMP-2 positively correlated with BMP-4 (P < 0.001, Spearman rank correlation test). The amounts of BMP-4 in both muscles increased significantly with age (P = 0.0003). CONCLUSIONS: Resected tissue from the lateral and medial rectus muscles had different levels of expression of TIMP-1 and 2, MMP-2, and BMP-4. These molecular differences may underlie different characteristics of the two extraocular muscles and may also influence the process of wound healing after strabismus surgery.

Adolescent↗

PubMed1978

Evaluation of a fluorescent dust tracer technique in cotton ginning.

A technique employing a fluorescent tracer for following the break-up and dispersion of cotton trash has been developed. Senescent cotton leaves were treated with a fluorescent dye, pulverized to match the same particle size distribution as naturally occurring leaf in raw seed cotton and uniformly incorporated into the seed cotton mass prior to processing in a saw-type micro-gin. A control lot was similarly processed, excluding any dye. Airborne samples collected from the major fugitive dust emission points by standard techniques, macro trash samples collected from four locations, and the final condensed lint product clearly show that the use of such tracers is not only feasible but highly useful in determining the locations where respirable dust is emitted. From the fraction of labelled tracer material found at any site, the relative amounts of both total and respirable dust emissions of that plant component can be estimated from the known masses of dyed material added to a given mass of seed cotton. Estimates of the relative severity of fugitive dust emissions from various processing steps in a cotton gin are presented based on vertical elutriator, high volume and multistage cascade impactor sampler data.

Coloring Agents↗

PubMed1980

Quality control of estrogen receptor assays.

Four types of material have been used for the quality control of routine assays of estrogen receptors in human breast tumors. Pieces of hormone-dependent Nb rat mammary tumors gave a precision about 40%. Rat uteri and rat tumors pulverized at liquid nitrogen temperature and stored as powder yielded precision about 30%. Powdered and lyophilised human tumors appear the best with precision as good as 17%.

Animals↗

PubMedDate not supplied

Health consequences of the September 11 World Trade Center attacks: a review.

In the aftermath of the September 11 World Trade Center (WTC) attack, a large number of people sustained potential exposures to smoke, dust, particulate matter, and a variety of toxins, including asbestos, pulverized concrete, glass fibers, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated furans and dioxins. Additionally, many had exposure to psychological traumatogens. The most common effects seen to date are respiratory and mental health consequences. The long-term consequences of exposures are not yet known, and there remains concern about the potential for late-emerging diseases such as cancers. This article reviews WTC-related health effects, the spectrum of exposures and how they were documented, and discusses future preventive efforts.

Air Pollutants↗

PubMed1999

In vitro effects of coal fly ashes: hydroxyl radical generation, iron release, and DNA damage and toxicity in rat lung epithelial cells.

Oxygen radical generation due to surface radicals, inflammation, and iron release has been suggested as the mechanism of adverse effects of quartz, such as emphysema, fibrosis, and carcinogenic effects. Therefore, we measured iron release, acellular generation of hydroxyl radicals, and oxidative DNA damage and cytotoxicity in rat lung epithelial (RLE) cells by different coal fly ashes (CFA) that contain both quartz and iron. Seven samples of CFA with different particle size and quartz content (up to 14.1%) were tested along with silica (alpha-quartz), ground coal, and coal mine dust (respirable) as positive control particles, and fine TiO(2) (anatase) as a negative control. Five test samples were pulverized fuel ashes (PFA), two samples were coal gasification (SCG) ashes (quartz content <0.1%), and one sample was a ground coal. No marked differences between SCG and PFA fly ashes were observed, and toxicity did not correlate with physicochemical characteristics or effect parameters. Stable surface radicals were only detected in the reference particles silica and coal mine dust, but not in CFA. On the other hand, hydroxyl radical generation by all fly ashes was observed in the presence of hydrogen peroxide, which was positively correlated with iron mobilization and inhibited by deferoxamine, but not correlated with iron or quartz content. Also a relationship between acellular hydroxyl radical generation and oxidative DNA damage in RLE cells by CFA was observed. Differences in hydroxyl radical generation and oxidative damage by the CFA were not related to iron and quartz content, but the respirable ashes (MAT023, 38, and 41) showed a very extensive level of hydroxyl radical generation in comparison to nonrespirable fly ashes and respirable references. This radical generation was clearly related to the iron mobilization from these particles. In conclusion, the mechanisms by which CFA and the positive references (silica, coal mine dust) affect rat lung epithelial cells seem to be different, and the data suggest that quartz in CFA does not act the same as quartz in silica or coal mine dust. On the other hand, the results indicate an important role for size and iron release in generation and subsequent effects of reactive oxygen species caused by CFA.

Animals↗

PubMed2000

Nutritional response of rats to faba beans (Vicia faba L. minor black 'Kalimattar') and its fractions.

The investigations on protein quality of raw faba bean seed meal (Vicia faba L. minor) and its fractions were carried out using rats in two experiments. Two varieties of faba seeds were used, locally grown faba bean 'Kalimattar' or 'black' (KSM) (492 g/kg diet) and its exotic counterpart Vicia faba L. minor 'White' (VFW) obtained from International Centre for Agricultural Research in the Dry Areas (ICARDA) (540 g/kg diet). The pulverized cotyledons of 'Kalimattar' (KMC; 438 g/kg diet), hull (KMH; 78 g/kg diet) as well as cotyledons of 'White' faba bean (VFWC; 470 g/kg diet) and hull (VFWH; 82 g/kg diet) fractions were tested. All diets were made isocaloric and isonitrogenous, however, without addition of individual amino acids to the target requirements. Performance of rats fed on both locally grown KSM and exotic FBW meal-fed rats were found to be inferior to those obtained from the rats fed on standard protein diet. The net protein utilization (NPU) of the rats fed on this seed meal was comparatively better than those obtained from the VFW. Replacement of standard protein with cotyledons from the either of the seed (KMC and VFWC) depressed food intake and protein utilization. This was due, in part, to the excretion of comparatively higher amount of nitrogen in faeces. Inclusion of KMH in the diet had no adverse effects on any variable studies as compared to the VFWH, which was found to impose severe restriction on the absorption of standard protein added to this diet. As a result, body weight gain, and NPU value were significantly lower than those obtained from the KMH. We conclude that the locally grown faba bean 'Kalimattar' is better than those of exotic 'White' cultivar and may contain less antinutritional substances. However, this warrants further investigations.

Animals↗

PubMed1998

Inorganic aerosols and their role in catalyzing sulfuric acid production in furnaces.

Submicrometer ash and sulfur oxides are important pollutants formed during pulverized coal combustion. The submicrometer ash contains known catalysts for sulfur dioxide oxidation as well as alkaline species that will react with sulfur oxides. This work was an investigation to determine if submicrometer ash-sulfur oxide interactions can have a significant impact on the fate of sulfur. The submicrometer-ash-sulfur oxide interaction studies were carried out using submicrometer ash of controlled composition generated from the combustion of synthetic chars. The submicrometer ash was either exposed to SO2 in the combustion chamber or immobilized on a quartz-fiber filter for later exposure to SO2. Submicrometer-ash catalysis of SO2 oxidation was found to contribute significantly to the SO3 formed in the convective passes of a utility boiler, depending on the coal, combustion conditions, and temperature profile in the convective section. The calcium within the freshly formed submicrometer ash appears to sulfate more rapidly than would be predicted from rates published in the literature and is expected to sulfate completely in the convective section of a utility boiler.

Aerosols↗

PubMed2001

Source profiles of particulate matter emissions from a pilot-scale boiler burning North American coal blends.

Recent awareness of suspected adverse health effects from ambient particulate matter (PM) emission has prompted publication of new standards for fine PM with aerodynamic diameter less than 2.5 microm (PM2.5). However, scientific data on fine PM emissions from various point sources and their characteristics are very limited. Source apportionment methods are applied to identify contributions of individual regional sources to tropospheric particulate concentrations. The existing industrial database developed using traditional source measurement techniques provides total emission rates only, with no details on chemical nature or size characteristics of particulates. This database is inadequate, in current form, to address source-receptor relationships. A source dilution system was developed for sampling and characterization of total PM, PM2.5, and PM10 (i.e., PM with aerodynamic diameter less than 10 pm) from residual oil and coal combustion. This new system has automatic control capabilities for key parameters, such as relative humidity (RH), temperature, and sample dilution. During optimization of the prototype equipment, three North American coal blends were burned using a 0.7-megawatt thermal (MWt) pulverized coal-fired, pilot-scale boiler. Characteristic emission profiles, including PM2.5 and total PM soluble acids, and elemental and carbon concentrations for three coal blends are presented. Preliminary results indicate that volatile trace elements such as Pb, Zn, Ti, and Se are preferentially enriched in PM2.5. PM2.5 is also more concentrated in soluble sulfates relative to total PM. Coal fly ash collected at the outlet of the electrostatic precipitator (ESP) contains about 85-90% PM10 and 30-50% PM2.5. Particles contain the highest elemental concentrations of Si and Al while Ca, Fe, Na, Ba, and K also exist as major elements. Approximately 4-12% of the materials exists as soluble sulfates in fly ash generated by coal blends containing 0.2-0.8% sulfur by mass. Source profile data for an eastern U.S. coal show good agreement with those reported from a similar study done in the United States. Based on the inadequacies identified in the initial sampling equipment, a new, plume-simulating fine PM measurement system with modular components for field use is being developed for determining coal combustion PM source profiles from utility boiler stacks.

Air Movements↗

PubMed2002

The fate and behavior of mercury in coal-fired power plants.

For the past 22 years in the Netherlands, the behavior of Hg in coal-fired power plants has been studied extensively. Coal from all over the world is fired in Dutch power stations. First, the Hg concentrations in these coals were measured. Second, the fate of the Hg during combustion was established by performing mass balance studies. On average, 43 +/- 30% of the Hg was present in the flue gases downstream of the electrostatic precipitator (ESP; dust collector). In individual cases, this figure can vary between 1 and 100%. Important parameters are the Cl content of the fuel and the flue gas temperature in the ESP. On average, 54 +/- 24% of the gaseous Hg was removed in the wet flue-gas desulfurization (FGD) systems, which are present at all Dutch coal-power stations. In individual cases, this removal can vary between 8% (outlier) and 72%. On average, the fate of Hg entering the power station in the coal was as follows: <1% in the bottom ash, 49% in the pulverized fuel ash (ash collected in the ESP), 16.6% in the FGD gypsum, 9% in the sludge of the wastewater treatment plant, 0.04% in the effluent of the wastewater treatment plant, 0.07% in fly dust (leaving the stack), and 25% as gaseous Hg in the flue gases and emitted into the air. The distribution of Hg over the streams leaving the FGD depends strongly on the installation. On average, 75% of the Hg was removed, and the final concentration of Hg in the emitted flue gases of the Dutch power stations was only -3 microg/m3(STP) at 6% O2. During co-combustion with biomass, the removal of Hg was similar to that during 100% coal firing. Speciation of Hg is a very important factor. An oxidized form (HgCl2) favors a high degree of removal. The conversion from Hg0 to HgCl2 is positively correlated with the Cl content of the fuel. A catalytic DENOX (SCR) favors the formation of oxidized Hg, and, in combination with a wet FGD, the total removal can be as high as 90%.

Air Pollutants↗

PubMed2002

Removal of PCDD/F from incinerator flue gases by entrained-phase adsorption.

The emission abatement of polychlorinated dioxins and furans (PCDD/F) Issued from municipal solid waste incineration is growing in importance because of more stringent emission standards and general concern about their toxic characteristics. These substances cannot be separated by conventional gas cleanup processes but are successfully removed through adsorption onto carbonaceous materials. The simplest technique is the entrained-phase injection of pulverized adsorbents in the flue gas, followed by fabric filter separation. The various related techniques are briefly reviewed here. Operating conditions and results obtained from Flemish MSWIs are given. The results illustrate the excellent overall removal efficiency. Furans are adsorbed to a slightly higher extent than dioxins. PCDD/F removal by carbonaceous adsorbents is thereafter modeled from first principles for the contribution of both entrained-phase (eta1) and cake filtration (eta2) to the overall efficiency (etaT). Application of the model equations and comparison of measured and predicted overall efficiencies for the Flemish municipal solid waste incinerators (MSWIs) demonstrate that the approach is meaningful and that the dominant parameters are the operating temperature, the dosage and activity of adsorbent, and the fraction of adsorbent in the filter cake. The model equations enable the MSWI operators to predict the adsorption efficiencies for any combination of operating parameters and to assess the sensitivity of the process to varying operating conditions.

Adsorption↗

PubMed2003

Latent hydraulic reactivity of blended cement incorporating slag made from municipal solid waste incinerator fly ash.

The reactivity of cement pastes made by blending Portland cement with slag from municipal solid waste incinerator (MSWI) fly ash was investigated to assess the potential of recycling MSWI fly ash slag. The slag, prepared by melting MSWI fly ash at 1400 degrees C for 30 min, was pulverized and ground, then blended with ordinary Portland cement (OPC), using various substitution levels to make slag-blended cement (SBC). The pozzolanic reactivity of the ecocement was then characterized by determining variations in the compressive strength, degree of hydration, microstructure, speciation, and mineralogical crystalline phases. The results suggest that the strength of the pastes at an early age decreased with increasing substitution levels, whereas the strength at a later age of the tested pastes (with substitution levels less than 10%) outperformed OPC paste because of typical SBC properties. The development of strength at a later age was also confirmed by X-ray diffraction and scanning electron microscopy techniques. This implies that active silica (Si) and alumina (Al) react with the hydration product, calcium hydroxide (Ca(OH)2), to form calcium silicate hydrate (C-S-H), which contributed to strength development at a later age by the filling up of pores in the SBC pastes. The pozzolanic activity of the SBC pastes indicates that it is suitable for use as a substitute for OPC in blended cement.

Conservation of Natural Resources↗

PubMed2004

Evaluation of vacuum and wet-wipe methods for removal of World Trade Center dust from indoor environments.

The destruction of the buildings at the World Trade Center (WTC) complex dispersed dust and debris into the surrounding area. Pulverized building material made up most of the fallout and was intermixed with combustion byproducts of the aircraft and building contents. A study was conducted to confirm the effectiveness of several cleaning procedures in removing WTC-related contamination from lower Manhattan residences. The contaminants included asbestos, lead, dioxin/furans, synthetic vitreous fibers (fibrous glass), and crystalline silica. All cleaning procedures included the common elements of vacuuming and wet wiping with soap and water. This cleaning procedure combination is effective in reducing WTC-related contamination to below health-based benchmarks. Post-cleaning environmental test results suggested that airborne asbestos measurements can be used as a surrogate parameter in clearance determinations.

Air Pollution, Indoor↗

PubMed2005

Effect of flow distributors on uniformity of velocity profile in a baghouse.

In recent years, the utility industry has turned to baghouses as an alternative technology for particulate emission control from pulverized-coal-fired power plants. One of the more significant issues is to improve poor gas distribution that causes bag failures in baghouse operation. Bag failures during operation are almost impossible to prevent, but proper flow design can help in their prevention. This study investigated vertical velocity profiles below the bags in a baghouse (the hopper region) to determine whether flow could be improved with the installation of flow distributors in the hopper region. Three types of flow distributors were used to improve flow distribution and were compared with the original baghouse without flow distributors. Velocity profiles were measured by a hot-wire anemometer at an inlet velocity of 18 m/sec. Uniformity of flow distribution was calculated by the uniformity value U for the velocity profile of each flow distributor. Experimental results showed that the velocity profile of the empty configuration (without flow distributors) was poor because the uniformity value was 2.048. The uniformity values of type 1 (flow distributor with three vertical vanes), type 2 (flow distributor with one vertical and one inclined vane), and type 3 (flow distributor with two inclined vanes) configurations were reduced to 1.051, 0.617, and 0.526, respectively. These results indicate that the flow distributors designed in this study made significant improvements in the velocity profile of a baghouse, with the type 3 configuration having the best performance.

Air Movements↗

PubMed2006

Pozzolanic reactivity of the synthetic slag from municipal solid waste incinerator cyclone ash and scrubber ash.

This study investigates the pozzolanic reactions and compressive strength of the blended cement manufactured using synthetic slag obtained from municipal solid waste incinerator (MSWI) cyclone ash and scrubber ash as partial replacement of portland cement. The synthetic slag was made by co-melting the MSWI scrubber ash and cyclone ash mixtures at 1400 degrees C for 30 min. Following pulverization, the different types of slag were blended with cement as cement replacement at ratios ranging from 10 to 40 wt %. The synthetic slag thus obtained was quantified, and the characteristics of the slag-blended cement pastes were examined. These characteristics included the pozzolanic activity, compressive strength, hydration activity, crystal phases, species, and microstructure at various ages. The 90-day compressive strength developed by slag-blended cement pastes with 10 and 20 wt % of the cement replaced by the synthetic slag outperformed ordinary portland cement by 1-7 MPa. X-ray diffraction species analyses indicated that the hydrates in the slag-blended cement pastes were mainly portlandite, the calcium silicate hydrate gels, and calcium aluminate hydrate salts, similar to those found in ordinary portland cement paste. Differential thermal and thermogravimetric analysis also indicated that the slag reacted with portlandite to form calcium silicate hydrate gels.

Air Pollution↗