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1.
J Occup Environ Med ; 37(7): 850-5, 1995 Jul.
Article in English | MEDLINE | ID: mdl-7552470

ABSTRACT

Inhalation of toxic substances in the workplace can result in a variety of respiratory disorders. One relatively rare sequela of the inhalation of toxic fumes is bronchiolitis obliterans, a condition characterized by fibrosis and narrowing of the small airways. Several substances have been reported to cause bronchiolitis obliterans, including ammonia, chlorine, hydrogen fluoride, hydrogen sulfide, nitrogen dioxide, ozone, phosgene, and other irritant fumes. Little has been reported on the pulmonary effects of fly ash produced by the incineration of coal and oil. We report a case of bronchiolitis obliterans with a component of partially reversible airway obstruction in a 39-year-old male occupationally exposed to incinerator fly ash.


Subject(s)
Bronchiolitis Obliterans/etiology , Carbon/adverse effects , Occupational Diseases/etiology , Adult , Bronchiolitis Obliterans/complications , Bronchiolitis Obliterans/diagnostic imaging , Coal Ash , Humans , Male , Occupational Diseases/complications , Occupational Diseases/diagnostic imaging , Particulate Matter , Radiography
2.
J Dairy Sci ; 78(3): 506-14, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7782508

ABSTRACT

The effects of pressure, temperature, residence time, and mass of skim milk on some characteristics of casein, prepared by precipitation with high pressure CO2, were examined in a batch reactor. For a 500-g milk sample, precipitation occurred at pressures > 2760 kPa and temperatures > 32 degrees C. Residence time was not significant and was held at 5 min. Yields were maximum at 2750 to 5520 kPa and at 38 to 49 degrees C for a 500-g milk sample. The resulting whey had a pH of 6.0. The casein product had an acceptable appearance and had greater solids, ash, and Ca contents than commercial acid caseins. Particle size distribution studies showed that the mean particle size was sensitive to precipitation pressure and temperature and was similar to that of acid caseins produced under laboratory conditions. The HPLC studies of the casein and whey fractions showed that precipitation by CO2 did not result in fractionation of casein or whey proteins to their component proteins.


Subject(s)
Carbon Dioxide , Caseins/isolation & purification , Milk/chemistry , Animals , Calcium/analysis , Chemical Precipitation , Chromatography, High Pressure Liquid , Hydrogen-Ion Concentration , Milk Proteins/isolation & purification , Particle Size , Pressure , Temperature , Whey Proteins
3.
Plant Physiol ; 93(2): 778-84, 1990 Jun.
Article in English | MEDLINE | ID: mdl-16667536

ABSTRACT

The extent of phosphate uptake measured by the relative changes in cytoplasmic Pi, vacuolar Pi, ATP, glucose-6-phosphate, and UDPG was determined using in vivo(31)P nuclear magnetic resonance spectroscopy. Maize (Zea mays) root tips were perfused with a solution containing 0.5 or 1.0 millimolar phosphate at pH approximately 6.5 under different conditions. In the aerated state, phosphate uptake resulted in a significant increase (>80%) in vacuolar Pi, but cytoplasmic Pi only transiently increased by 10%. Under N(2), the cytoplasmic Pi increased approximately 150% which could be attributed to a large extent to the breakdown of ATP, sugar phosphates and UDPG. Vacuolar Pi increased but only to the extent of approximately 10% of that seen under aerobic conditions. 2-deoxyglucose pretreatment was utilized to decrease the level of cytoplasmic Pi. When pretreated with the 2-deoxyglucose, the excised maize roots absorbed phosphate from the perfusate with a significant increase in the cytoplasmic Pi. The increase could only be traced to external phosphate since the concentrations of other phosphorus containing species remained constant during the uptake period. With 2-deoxyglucose pretreatment, phosphate uptake under anaerobic conditions was substantially inhibited with only the vacuolar phosphate showing a slight increase. When roots were treated with carbonyl cyanide m-chlorophenyl hydrazone, no detectable Pi uptake was found. These results were used to propose a H(+)-ATPase related transport mechanism for phosphate uptake and compartmentation in corn root cells.

4.
Plant Physiol ; 89(4): 1238-46, 1989 Apr.
Article in English | MEDLINE | ID: mdl-16666690

ABSTRACT

(31)P NMR spectroscopy was used to study in vivo the symbiotic state established between soybean (Glycine max [L.] Merr. cv Williams) and Bradyrhizobium japonicum (USDA 110 and 138). Different experimental conditions were used to maintain perfused, respiring detached or attached nodules in an NMR magnet. The pH of the perfusion medium affected the cytoplasmic pH and the resolution of the spectra. The internal Pi content and distribution were assessed as a function of nodule age and green-house growth conditions and the rate of glucose and 2-deoxyglucose uptake into nodules in split and intact states. The major metabolites (glucose-6-P, fructose-1,6-diP, P-choline, Pi, NTP, UDP-glc, and NAD) were readily identified from (31)P NMR spectra of perchloric acid extracts of nodules with the exception of one unknown phosphorus metabolite. Nodules stressed by glucose deprivation demonstrated movement of Pi between the vacuole and cytoplasmic compartments not previously observed in (31)P NMR studies.

5.
Planta ; 172(2): 200-8, 1987 Oct.
Article in English | MEDLINE | ID: mdl-24225871

ABSTRACT

The effects of aluminum ions on the generation of mobile inorganic phosphate (Pi) within the cells of excised maize (Zea mays L.) root tips were examined using (31)P-nuclear magnetic resonance ((31)P-NMR) spectroscopy. When perfused with a solution containing 50 mM glucose and 0.1-5.0 mM Ca(2+) at pH 4.0, 3-5-mm-long excised maize root tips from 3-d-old seedlings showed a significant (approx. 100%) increase in the amount of mobile Pi, (primarily vacuolar) over a period of 30 h. This increase was above that which can be accounted for by the hydrolysis of endogenous sugar phosphates and nucleotides. A change of the pH of the perfusion solution to 7.0 reduced the increase in Pi to approx. 50%. Omission of Ca(2+) in the solution at pH 4.0 caused the mobile Pi to increase to about 170%. However, the presence of Al(3+) or both Ca(2+) and Al(3+) in the solution resulted in a significant loss (35-50%) of mostly vacuolar Pi over the same period of time. When root tips containing up to 65% of newly released Pi, produced after 20 h perfusion, were exposed to Al(3+), no additional increase in the level of the mobile-Pi signal area was noted. Exposure to Al(3+) with Ca(2+) and glucose under hypoxia at pH 4.0 resulted in a threefold decrease in intracellular Pi content after the root tips were returned to aerobic conditions. These results indicate that external pH plays an important role in the generation of mobile intracellular Pi and that the presence of both Ca(2+) and Al(3+) can independently suppress the production of this excess Pi and ultimately reduce the vacuolar Pi.

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