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PubMed1992

[General rules of infection prevention in organ transplantation, bone marrow transplantation and prosthetic surgery].

General rules to prevent are categorized into four classes. The first one concern patient before operation: well-balanced nourishment latent infections treatment, digestive tract micro flora elimination, immunizations, antiseptic gargles, skin antisepsis. The second one concern operation: previous fumigation, very high efficiency filtration and laminar flow air, transplant care, antibioprophylaxis, operating theatre discipline. The third one concern post-operation days: cubicle initial fumigation, high efficiency filtration and positive pressure air, strict protective insulation, single-use things, controlled food, specific anti viral prevention, catheters and tubes removal or replacement. The fourth one concern going home patient: well-balanced nourishment, body hygiene and hands washing, infected people shunning, gardening and cleaning proscribing, medical follow-up and latent infections systematic detection.

Bone Marrow Transplantation↗
PubMedDate not supplied

Effects of environmental factors on 1,3-dichloropropene hydrolysis in water and soil.

Hydrolysis is the major pathway for fumigant 1,3-dichloropropene (1,3-D) degradation in water and soil, yet the process is not well understood. Experiments were conducted to investigate the effect of various environmental factors on the rate of 1,3-D hydrolysis. Cis-, trans-1,3-D and their isomeric mixture were spiked into water and Arlington soil (coarse-loamy, mixed, thermic Haplic Durixeralfs) and incubated under different conditions. The rate of 1,3-D hydrolysis in water and soil were evaluated based on its residual amount and Cl- release, respectively. 1,3-D hydrolyzed rapidly in deionized water, with a half-life of 9.8 d at 20 degrees C. The hydrolysis was pH dependent, with low pH inhibiting and high pH favoring the reaction. Other factors such as isomeric differences, photo irradiation, suspended particles, and small amounts of co-solutes had little effect on the reaction. In soil, 1,3-D hydrolyzed following pseudo first-order kinetics. The hydrolysis rate constant increased with soil moisture content and decreased with the initial 1,3-D concentration. At 20 degrees C, > 60% of the 1,3-D applied at < 0.61 g kg(-1) in 10% moisturized soil hydrolyzed within 30 d. The soil particle size and mineralogy had little effect on the reaction rate. Organic matter promoted 1,3-D degradation via direct substitution reactions, and the trans-isomer showed preference over the cis- to react with certain organic molecules. Microbial contributions were initially insignificant, and became important as soil microorganisms adapted to the fumigant. The results suggest that to accelerate 1,3-D degradation, pH, soil moisture, and organic amendment should be considered.

Allyl Compounds↗
PubMed2004

Atmospheric volatilization and distribution of (Z)- and (E)-1,3-dichloropropene in field beds with and without plastic covers.

The fumigant 1,3-dichloropropene (1,3-D) is considered to be a potential replacement for methyl bromide when methyl bromide is phased out in 2005. This study on surface emissions and subsurface diffusion of 1,3-D in a Florida sandy soil was conducted in field beds with or without plastic covers. After injection of the commercial fumigant Telone II by conventional chisels to field beds at 30cm depth which were covered with polyethylene film (PE), virtually impermeable film, or no cover (bare), (Z)- and (E)-1,3-D rapidly diffused upward. Twenty hours after injection, majority of (Z)- and (E)-1,3-D had moved upward from 30 cm depth to the layer of 5-20 cm depth. Downward movement of the two isomers in the beds with or without a plastic cover was not significant. (Z)-1,3-D diffused more rapidly than (E)-1,3-D. Virtually impermeable films (VIF) had a good capacity to retain (Z)- and (E)-1,3-D in soil pore air space. Vapor concentrations of the two isomers in the shallow subsurface of the field bed covered with VIF were greater than that in the two beds covered with polyethylene film (PE) or no cover (bare). In addition, VIF cover provided more uniform distribution of (Z)- and (E)-1,3-D in shallow subsurface than PE cover or no cover. Virtually impermeable film also had a better capability to retard surface emissions of the two isomers from soil in field beds than PE cover or no cover.

Agriculture↗
PubMed2006

[Study on influence of processing methods on chemical constituents in Radix Paeoniae Alba].

OBJECTIVE: The influence of processing methods on chemical constituents in Radix Paeoniae Alba was observed. METHOD: A HPLC method was used for analyzing the changes of eight major constituents, namely gallic acid, paeoniflorin sulfonate, catechin, paeoniflorin sulfonate, albiflorin, paeoniflorin, benzoic acid, pentagalloylglucose and benzoylpaeoniflorin, with the three processing procedures of decorticating, boiling and fumigating by burning of sulphur. Analysis was performed using a Zorbax SB-C18 column (4.6 mm x 250 mm, 5 microm) with the mixture of acetonitrile (A) and 0.015% phosphoric acid solution as mobile phase in gradient mode. The detection wavelength was set at 230 nm and the column temperature was at 30 degrees C. RESULT: Except for gallic acid and pentagalloylglucose, the other constituents decreased during procedure of decorticating and boiling. Fumigating by burning of sulphur would produce a new compound, paeoniflorin sulfonate, which was a byproduct from the reaction of paeoniflorin with SO2. CONCLUSION: The significant changes were produced in chemical constituents of Radix Paeoniae Alba during three processing procedures. Therefore, the processing of Radix Paeoniae Alba should be strictly controlled and standardized.

Benzoates↗
PubMedDate not supplied

[Evaluation of the effect of a single dose of ammonia on lettuce photosynthesis in a hermetically sealed phytotron].

The threshold of the phytotoxic effect (PTE) of ammonia at a concentration of 10 to 20 mg/m3 on 28-day lettuce plants was evaluated during a single 2-hour exposure. The rate of Hill's reaction, level of energization of chloroplast membranes during leaf illumination as well as visible photosynthesis of lettuce plants from the beginning of fumigation to vegetation day 31 were recorded. Similar changes in the above parameters induced by ammonia were seen. This suggests that photosynthesis was inhibited already at light stages. As a measure of PTE, 10 per cent decrease of the photosynthetic productivity of plants exposed to fumigation was recommended in comparison with controls during the vegetation period. According to this measure, the PTE of ammonia amounted to 20 mg/m3 in the above experimental conditions.

Ammonia↗
PubMed1977

Mutagenicity of pesticides containing 1,3-dichloropropene.

In a systematic study of the mutagenic effect of chemical compounds used as pesticides, we found that D. D. soil fumigant and Telone are mutagenic. The test was performed using the bacterial tester strains following the procedure developed by Ames. The active principle of D. D. soil fumigant and Telone is a mixture of the cis and trans isomers of 1,3-dichloropropene. Both isomers are mutagenic in Salmonella strains TA 1535 and TA 100. 2,3-Dichloro-1-propene, a minor component (5%) of the commercial preparation Telone, was also found to be mutagenic in strains TA 1535 and TA 100. Mutagenesis of these tester strains is an indication of a base-pair substitution event causing a missense mutation. 1,3-Dichloropropene is widely used in agriculture all over the world. In Italy 2,187,100 kg were produced in 1972. In California over 1,000,000 kg of 1,3-dichloropropene-containing pesticides were used in 1971.

Allyl Compounds↗
PubMedDate not supplied

Simultaneous analysis of grain and grain-based products for ethylene dibromide, carbon tetrachloride, and ethylene dichloride.

A method is described for the simultaneous measurement of parts per billion levels of the fumigants ethylene dibromide, carbon tetrachloride, and ethylene dichloride in grain and grain-based products. The fumigants are isolated by hexane co-distillation, separated by capillary gas chromatography, and detected with a mass spectrometer in the selected ion monitoring mode. Recoveries are greater than 90% and standard deviations are approximately 10% of the quantity measured. The method is free of interferences and its precision and accuracy are enhanced by the use of tetradeuterated ethylene dibromide and ethylene dichloride as internal standards.

Carbon Tetrachloride↗
PubMed1978

[Epizootic of S. heidelberg in poultry breeding flocks raised commercially].

It was noted that under the conditions of industrial raising of adult birds the epizootic of Salmonella heidelberg could assumme an acute course with a clinical manifestation. After its short-term acute manifestation the infection acquired a protracted course. Mortality correlated directly with the age of the birds. Isolated and identified were a total of 117 Salmonella heidelberg strains from carcasses, cloacal samples, eggs, and litter. Regardless of the short-term Salmonella harbouring the deep litter was shown to predispose to reinfections. The isolation of eight strains of S. heidelberg from the egg shell and the yolk of freshly laid eggs as well as the negative microbial findings in one- and two-fold fumigated eggs corroborate the idea of the additional entering of Salmonella organisms through the shell. These also point to the fact that fumigation carried out up to the third hour following laying may contribute to the raising of disease-free broilers. Treatment with furazolidon and chloramphenicol in combination or the application of salmocid at the rate of 250 milligram microgram of feed in the course of ten days suppresses the acute manifestation of the disease and restores the productivity of birds, having no effect on the harbouring of the infection in the flock.

Animals↗
PubMed1982

[The practice of ethylene oxide sterilization].

Complete and rapid removal of ethylene oxide used for fumigation and its conversion products are of critical importance when reusing gas-sterilized parts of instruments. Evaluation of desorption is possible by means of gaschromatographic analyses of the atmosphere in packs containing the instruments for fumigation and storage. Residual amounts for a number of selected parts of instruments shown suggest latent sources of danger. The dimension of the instruments, the differences in plastic materials and ethylene oxide permeability of packing materials play a significant, though not obvious, role. Since no general rules concerning the duration of desorption can be established in view of these various factors, occasional examinations by means of gaschromatographic analyses are necessary.

Catheterization↗
PubMedDate not supplied

Determination of phosphine residues in whole grains and soybeans by ion chromatography via conversion to phosphate.

An ion chromatographic (IC) method was developed for determining phosphine (PH3) in whole grains (barley, corn, oats, rice, rye, and wheat) and soybeans. The method converts phosphine to phosphate (i.e., orthophosphate) and isolates the phosphate by IC with eluent-suppressed conductivity detection. Recoveries of unbound phosphine by the method were similar to those obtained by an established colorimetric method for 7 different products fortified at 3 levels. Mean recoveries were low (i.e., 30-60%) and varied with product type and level of fortification. Recoveries of PH3 from previously fumigated products fortified with aluminum phosphide ranged from 19.0% for barley fortified at 0.734 ppm to 88.3% for corn fortified at 1.691 ppm. Precision data from 3 products based on replicate analyses (n = 4 or 5) gave relative standard deviations of 1.78-4.66% for mean laboratory-fumigated PH3 levels of 0.679-1.309 ppm. Estimated limits of detection (LOD) and quantitation (LOQ) for PH3 were 0.010 microgram/g (10 ppb) and 0.0275 microgram/g (27.5 ppb) at signal-to-noise ratios (S/N) of 4:1 and 10:1, respectively. These values were also determined for a nonchemically suppressed IC system with LOD of 0.02 microgram/g (20 ppb) and LOQ of 0.055 microgram/g (55 ppb) at S/N of 4:1 and 10:1, respectively. Phosphate response was linear over the concentration range equivalent to 0.30-10.0 micrograms P/mL, with a mean correlation coefficient of 0.9988 based on replicate standard curves. The relationship of product composition to recovery from various products was also examined.

Aluminum Compounds↗
PubMed1995

Two-dimensional electrophoresis of thylakoid protein patterns in two wheat cultivars with different sensitivity to sulfur dioxide.

Plants of two wheat cultivars (Triticum aestivum L., cultivars Mec and Chiarano), differing in sensitivity towards sulfur dioxide, were fumigated with 96 nL L-1 of SO2 for four months. Thylakoid membranes were subjected to two-dimensional electrophoresis in order to detect possible changes in the protein patterns. We found the greatest alterations following treatment in the polypeptide profiles of the most sensitive cultivar, Mec, even if some significant changes were also detected in the plants of the cultivar Chiarano.

Electrophoresis, Gel, Two-Dimensional↗
PubMed2003

Inhibition of egg development by phosphine in the cosmopolitan pest of stored products Liposcelis bostrychophila (Psocoptera: Liposcelididae).

Phosphine-induced delay in development of eggs was investigated as a mechanism of resistance to this fumigant in Liposcelis bostrychophila Badonnel. One-day-old eggs of a susceptible and a strongly resistant strain of L bostrychophila were exposed to a range of phosphine concentrations for 6days at 30 (+/- 1) degrees C and 70 (+/- 2)% RH. Delay in mean hatching period occurred in both susceptible and resistant eggs, although it was more pronounced in the latter. A maximum delay of 2.65 days was recorded for eggs of the susceptible strain at 0.01 mg litre(-1) (the highest concentration at which eggs survived) and 13.39 days for the resistant strain at 1 mg litre(-1) (the highest concentration tested). Delay in egg development time was positively correlated with increasing phosphine concentration. Our results reveal that the most successful strategy to control resistant L bostrychophila is to apply relatively low concentrations of phosphine for extended exposure times (eg 0.05 mg litre(-1) for 16 days) that allow all eggs to hatch to the much less tolerant nymph stage.

Animals↗
PubMed2004

Influence of phosphine on hatching of Cryptolestes ferrugineus (Coleoptera: Cucujidae), Lasioderma serricorne (Coleoptera: Anobiidae) and Oryzaephilus surinamensis (Coleoptera: Silvanidae).

The hatching and mortality response of 0- to 48-h-old eggs of field strains of the stored-product insects Cryptolestes ferrugineus (Stephens), Lasioderma serricorne (F) and Oryzaephilus surinamensis (L) following phosphine fumigation for 24, 48 or 120 h at 27 (+/- 2) degrees C was investigated. Hatching was delayed and reduced in the first few days in a phosphine-resistant strain of C ferrugineus that was treated with 2.0-7.0 mg litre(-1) doses for 48 h (5-80% mortality) and with 1.0-2.0 mg litre(-1) for 120 h (44-84% mortality). In both the exposures there were significant increases in hatching on later days when compared with the corresponding controls. Developmental delay was, however, not evident in susceptible strains of C ferrugineus, L serricorne and O surinamensis that were exposed to phosphine for 24 h.

Animals↗
PubMed2004

Formation of unidentified nitrogen in plants: an implication for a novel nitrogen metabolism.

Plants take up inorganic nitrogen and store it unchanged or convert it to organic forms. The nitrogen in such organic compounds is stoichiometrically recoverable by the Kjeldahl method. The sum of inorganic nitrogen and Kjeldahl nitrogen has long been known to equal the total nitrogen in plants. However, in our attempt to study the mechanism of nitrogen dioxide (NO(2)) metabolism, we unexpectedly discovered that about one-third of the total nitrogen derived from (15)N-labeled NO(2) taken up by Arabidopsis thaliana (L.) Heynh. plants was converted to neither inorganic nor Kjeldahl nitrogen, but instead to an as yet unknown nitrogen compound(s). We here refer to this nitrogen as unidentified nitrogen ( UN). The generality of the formation of UN across species, nitrogen sources and cultivation environments for plants has been shown as follows. Firstly, all of the other 11 plant species studied were found to form the UN in response to fumigation with (15)NO(2). Secondly, tobacco ( Nicotiana tabacum L.) plants fed with (15)N-nitrate appeared to form the UN. And lastly, the leaves of naturally fed vegetables, grass and roadside trees were found to possess the UN. In addition, the UN appeared to comprise a substantial proportion of total nitrogen in these plant species. Collectively, all of our present findings imply that there is a novel nitrogen mechanism for the formation of UN in plants. Based on the analyses of the exhaust gas and residue fractions of the Kjeldahl digestion of a plant sample containing the UN, probable candidates for compounds that bear the UN were deduced to be those containing the heat-labile nitrogen-oxygen functions and those recalcitrant to Kjeldahl digestion, including organic nitro and nitroso compounds. We propose UN-bearing compounds may provide a chemical basis for the mechanism of the reactive nitrogen species (RNS), and thus that cross-talk may occur between UN and RNS metabolisms in plants. A mechanism for the formation of UN-bearing compounds, in which RNS are involved as intermediates, is proposed. The important broad impact of this novel nitrogen metabolism, not only on the general physiology of plants, but also on plant substances as human and animal food, and on plants as an integral part of the global environment, is discussed.

Fumigation↗
PubMed2006

Muscodor albus and its biological promise.

We have found a novel fungal genus that produces extremely bioactive volatile organic compounds (VOCs). This fungal isolate was initially discovered as an endophyte in Cinnamomum zeylanicum in a botanical garden in Honduras. This endophytic fungus, Muscodor albus, produces a mixture of VOCs that are lethal to a wide variety of plant and human pathogenic fungi and bacteria. It is also effective against nematodes and certain insects. The mixture of VOCs has been analyzed using GC/MS and consists primarily of various alcohols, acids, esters, ketones, and lipids. Final verification of the identity of the VOCs was carried out by using artificial mixtures of the putatively identified compounds and showing that the artificial mixture possessed the identical retention times and mass spectral qualities as those of the fungal derived substances. Artificial mixtures of the VOCs nicely mimicked the biological effects of the fungal VOCs when tested against a wide range of fungal and bacterial pathogens. Potential applications for "mycofumigation" by M. albus are currently being investigated and include uses for treating various plant parts, and human wastes. Another promising option includes its use to replace methyl bromide fumigation as a means to control soil-borne plant diseases.

Anti-Bacterial Agents↗
PubMed1985

Disposition of [14C]methyl bromide in rats after inhalation.

Methyl bromide is used as a disinfectant to fumigate soil and a wide range of stored food commodities in warehouses and mills. Human exposure occurs during the manufacture and use of the chemical. The purpose of this investigation was to determine the disposition and metabolism of [14C]methyl bromide in rats after inhalation. Male Fischer-344 rats were exposed nose only to a vapor concentration of 337 nmol [14C]methyl bromide/liter air (9.0 ppm, 25 degrees C, 620 torr) for 6 hr. Urine, feces, expired air, and tissues were collected for up to 65 hr after exposure. Elimination of 14C as 14CO2 was the major route of excretion with about 47% (3900 nmol/rat) of the total [14C]methyl bromide absorbed excreted by this route. CO2 excretion exhibited a biphasic elimination pattern with 85% of the 14CO2 being excreted with a half-time of 3.9 +/- 0.1 hr (means +/- SE) and 15% excreted with a half-time of 11.4 +/- 0.2 hr. Half-times for elimination of 14C in urine and feces were 9.6 +/- 0.1 and 16.1 +/- 0.1 hr, respectively. By 65 hr after exposure, about 75% of the initial radioactivity had been excreted with 25% remaining in the body. Radioactivity was widely distributed in tissues immediately following exposure with lung (250 nmol equivalents/g), adrenal (240 nmol equivalents/g), kidney (180 nmol equivalents/g), liver (130 nmol equivalents/g), and nasal turbinates (110 nmol equivalents/g) containing the highest concentrations of 14C. Radioactivity in livers immediately after exposure accounted for about 17% of the absorbed methyl bromide. Radioactivity in all other tissues examined accounted for about 10% of the absorbed methyl bromide. Elimination half-times of 14C from tissues were on the order of 1.5 to 8 hr. In all tissues examined, over 90% of the 14C in the tissues was methyl bromide metabolites. The data from this study indicate that after inhalation methyl bromide is rapidly metabolized in tissues and readily excreted.

Animals↗
PubMed1975

Toxicological implications of pesticides: their toxic effects on seeds of food plants.

Pesticides are widely used for the protection of economic crops from a variety of noxious pests. The repeated and indiscriminate uses and the extreme stability of certain pesticides have led to their accumulation in plants, animals, soils and sediments, thus effecting widespread contamination of the environment. Soil contaminants are especially serious because they can inhibit or impair the seed germination of our food and feed crops. Seeds can come in close contact with pesticides through processes such as prematurity application, fumigation, seed dressings, and seed treatments. Several reports have indicated the toxic effects of pesticides on seed germination. Possible mechanisms of the toxic action on pesticides during the germination of seeds have been discussed with emphasis on biochemical, histological, and cytological alterations. Bioassay procedures employing seed germination as a smiple, feasible, economical, time-saving indicator of toxicity have been described briefly. Attention is then drawn to the possible potential health hazards arising from the presence of pesticidal chemicals in food plants since the toxicological implications of long term exposure to pesticides are often more far-reaching.

Animals↗
PubMed1985

Progress on control of northern fowl mites on caged laying hens.

Recent research on methods for controlling the northern fowl mite (NFM) on caged laying hens is reviewed. On inanimate objects, NFM may be controlled by fumigation with methyl bromide, increased temperature (49 degrees C for 1 h), or decreased temperature (-20 degrees C for 5 days). dipping chickens in aqueous suspensions of carbaryl or stirofos controlled NFM for 6 weeks without exceeding current egg tolerance residues. Feeding chickens reasonable concentrations of systemic pesticides registered for use on dairy cattle in the U.S.A., registered anticoccidials, zinc bacitracin, avermectins, and diflubenzuron did not produce systemic control of NFM. Chickens do develop immunity to NFM. The potential for further development and adoption of these techniques should provide the poultry industry with effective alternatives to existing chemical sprays and dusts.

Animals↗