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Biological and ecophysiological reactions of white wall rocket (Diplotaxis erucoides L.) grown on sewage sludge compost.

We studied the effects of sewage sludge compost on white wall rocket (Diplotaxis erucoides L.) compared with mineral fertilization and control (without any fertilizer) in a greenhouse experiment. The plants grown on the compost-amended soil showed a different growth dynamic: a significant delay in flowering and a bigger root system. Both the compost and the fertilization treatments increased biomass and seed yield. Heavy metal (Cu, Cd, Zn, Ni) distribution within the plant was in the following order: roots > leaves > stems, except for zinc which was homogeneously distributed. The balance of mineral nutrition was not affected by treatments. Zinc was the trace element which was most taken up. Unlike many species of Brassicaceae, white wall rocket is not a hyperaccumulator. Although sewage sludge compost improved plant growth, delay in flowering shows that it is necessary to take precautions when spreading sewage sludge in natural areas.

Brassicaceae↗

Direct antioxidant activity of purified glucoerucin, the dietary secondary metabolite contained in rocket (Eruca sativa Mill.) seeds and sprouts.

Rocket (Eruca sativa Mill. or Eruca vesicaria L.) is widely distributed all over the world and is usually consumed fresh (leafs or sprouts) for its typical spicy taste. Nevertheless, it is mentioned in traditional pharmacopoeia and ancient literature for several therapeutic properties, and it does contain a number of health promoting agents including carotenoids, vitamin C, fibers, flavonoids, and glucosinolates (GLs). The latter phytochemicals have recently gained attention as being the precursors of isothiocyanates (ITCs), which are released by myrosinase hydrolysis during cutting, chewing, or processing of the vegetable. ITCs are recognized as potent inducers of phase II enzymes (e.g., glutathione transferases, NAD(P)H:quinone reductase, epoxide hydrolase, etc.), which are important in the detoxification of electrophiles and protection against oxidative stress. The major GL found in rocket seeds is glucoerucin, GER (108 +/- 5 micromol g(-)(1) d.w.) that represents 95% of total GLs. The content is largely conserved in sprouts (79% of total GLs), and GER is still present to some extent in adult leaves. Unlike other GLs (e.g., glucoraphanin, the bio-precursor of sulforaphane), GER possesses good direct as well as indirect antioxidant activity. GER (and its metabolite erucin, ERN) effectively decomposes hydrogen peroxide and alkyl hydroperoxides with second-order rate constants of k(2) = 6.9 +/- 0.1 x 10(-)(2) M(-)(1) s(-)(1) and 4.5 +/- 0.2 x 10(-)(3) M(-)(1) s(-) , respectively, in water at 37 degrees C, thereby acting as a peroxide-scavenging preventive antioxidant. Interestingly, upon removal of H(2)O(2) or hydroperoxides, ERN is converted into sulforaphane, the most effective inducer of phase II enzymes among ITCs. On the other hand, ERN (and conceivably GER), like other ITCs, does not possess any chain-breaking antioxidant activity, being unable to protect styrene from its thermally (37 degrees C) initiated autoxidation in the presence of AMVN. The mechanism and relevance of the antioxidant activity of GER and ERN are discussed.

Antioxidants↗

Fused rocket immunoelectrophoretic analysis of human and sheep thyroglobulins purified by gel chromatography.

The application of fused rocket immunoelectrophoretic methods for the analysis of human and sheep thyroid extracts is reported. Different experimental procedures, evaluating thyroglobulin preparations obtained by gel chromatographic separations with a variety of gel supports and elution conditions, were examined. Adsorption experiments demonstrated that many of the antigenic contaminants in chromatographed thyroglobulin were due to serum proteins. The precipitin profiles obtained with the fused rocket immunoelectrophoretic experiments indicate that considerable tailing of 19S-thyroglobulin occurs when chromatographed on either Sephadex G-200 or Bio-Gel A-1.5 m using low ionic strength buffers. The retention of thyroglobulin on these supports would account, in part, for the observed presence of thyroid proteins with antigenic determinants identical to 19S-thyroglobulin in chromatographed subfractions of notionally lower molecular weight. Because of the case of execution, the described methods provide a useful alternative to existing methods for the assessment of homogeneity of chromatographed thyroglobulin samples.

Animals↗

Development of rocket electrophoresis technique as an analytical tool in preformulation study of tetanus vaccine formulation.

Rocket Electrophoresis (RE) technique relies on the difference in charges of the antigen and antibodies at the selected pH. The present study involves optimization of RE run conditions for Tetanus Toxoid (TT). Agarose gel (1% w/v, 20 ml, pH 8.6), anti-TT IgG - 1 IU/ml, temperature 4-8 degrees C and run duration of 18 h was found to be optimum. Height of the rocket-shaped precipitate was proportional to TT concentration. The RE method was found to be linear in the concentration range of 2.5 to 30 Lf/mL. The method was validated and found to be accurate, precise, and reproducible when analyzed statistically using student's t-test. RE was used as an analytical method for analyzing TT content in plain and marketed formulations as well as for the preformulation study of vaccine formulation where formulation additives were tested for compatibility with TT. The optimized RE method has several advantages: it uses safe materials, is inexpensive, and easy to perform. RE results are less prone to operator's bias as compared to flocculation test and can be documented by taking photographs and scanned by densitometer; RE can be easily standardized for the required antigen concentration by changing antitoxin concentration. It can be used as a very effective tool for qualitative and quantitative analysis and in preformulation studies of antigens.

Bacterial Vaccines↗

Mechanically induced actin-mediated rocketing of phagosomes.

Actin polymerization can be induced in Dictyostelium by compressing the cells to bring phagosomes filled with large particles into contact with the plasma membrane. Asymmetric actin assembly results in rocketing movement of the phagosomes. We show that the compression-induced assembly of actin at the cytoplasmic face of the plasma membrane involves the Arp2/3 complex. We also identify two other proteins associated with the mechanically induced actin assembly. The class I myosin MyoB accumulates at the plasma membrane-phagosome interface early during the initiation of the response, and coronin is recruited as the actin filaments are disassembling. The forces generated by rocketing phagosomes are sufficient to push the entire microtubule apparatus forward and to dislocate the nucleus.

Actin-Related Protein 2-3 Complex↗

Rocket immunoelectrophoresis of C4 and C4d. A simple sensitive method for detecting complement activation in plasma.

Activation of complement component C4 has recently been measured by the quantitation of C4 and C4d (a cleavage fragment of C4) by electroimmunodiffusion in gels containing specific precipitating antibodies for C4 and C4d (Rocket immunoelectrophoresis, RIE). Quantitative measurements of the complement component C4 and its fragment C4d were determined in rocket immunoelectrophoresis (RIE) and compared with measurements of total hemolytic complement activity (CH50) or concentrations of C4 as determined by single radial immunodiffusion (RID). This newly developed RIE assay shows activation of the classical complement pathway and involves electroimmunodiffusion in gels containing specific precipitating antibodies for C4 and its cleavage fragment, C4d. In 37 plasma samples, excellent correlation was demonstrated between the C4 in RIE and CH50 (r = .70) and C4 by RID (r = .87). In vivo activation of C4 was determined by measuring the ratio of C4d to C4; 21 of the plasma samples assayed had ratios greater than 1.1 indicating activation of C4. In 13 of the plasma samples there were correspondingly low CH50 values, whereas 8 had normal CH50 levels. Therefore, activation can be detected in those instances when other measurements (CH50 and C4 quantitation) are normal. Thus the RIE assay for plasma C4 activation appears to be the most sensitive method available for assessing in vivo activation of the classical pathway of complement.

Animals↗

Antigenic relationships among mycobacterial species studied by modified-rocket and crossed immunoelectrophoresis.

The complexity of antigens from various species of mycobacteria was explored with use of variations in the techniques of fused-rocket immunoelectrophoresis (IEP) and two-dimensional IEP. Resolution and formation of lines of identity depended on shape and arrangement of antigen wells, concentration of reagents, and procedure for electrophoresis. Rocket IEP of a sonicate into heterologous antiserum in one dimension followed by IEP into homologous antiserum in a second dimension permitted ready identification of heterologous reactions, with direct identity to homologous precipitin bands. Variations in procedures provided versatility that permitted comparison of antigens of unknown or different species, expression of relatedness, comparison of different antisera, and progress of purification or fractionation.

Antigens, Bacterial↗

Chemical exposures of rocket-engine test-stand personnel and cancer mortality in a cohort of aerospace workers.

We conducted a retrospective cohort study of 6107 aerospace workers to examine whether exposure to chemicals--primarily hydrazine fuels--during rocket-engine fueling and testing affects cancer mortality. When conditional logistic regression analysis was applied and adjusted for confounding variables, the estimated rate ratio for lung cancer mortality, comparing exposed to unexposed workers from the same facility, ranged from 1.68 (95% confidence interval, 1.12 to 2.52) to 2.10 (95% confidence interval, 1.36 to 3.25), depending on job-duration threshold (6 or 24 months) and lag (0 to 15 years). Similar results were obtained for hemato- and lymphopoietic cancer and for bladder and kidney cancer mortality, but estimates for these cancers were imprecise. We concluded that occupational exposure to hydrazine or other chemicals associated with rocket-engine testing jobs increased the risk of dying from lung cancer, and possibly other cancers, in this population of aerospace workers; however, our results need to be replicated in other populations.

Carcinogens↗

Mortality among Rocketdyne workers who tested rocket engines, 1948-1999.

OBJECTIVE: The objective of this study was to evaluate potential health risks associated with testing rocket engines. METHODS: A retrospective cohort mortality study was conducted of 8372 Rocketdyne workers employed 1948 to 1999 at the Santa Susana Field Laboratory (SSFL). Standardized mortality ratios (SMRs) and 95% confidence intervals (CIs) were calculated for all workers, including those employed at specific test areas where particular fuels, solvents, and chemicals were used. Dose-response trends were evaluated using Cox proportional hazards models. RESULTS: SMRs for all cancers were close to population expectations among SSFL workers overall (SMR = 0.89; CI = 0.82-0.96) and test stand mechanics in particular (n = 1651; SMR = 1.00; CI = 0.86-1.16), including those likely exposed to hydrazines (n = 315; SMR = 1.09; CI = 0.75-1.52) or trichloroethylene (TCE) (n = 1111; SMR = 1.00; CI = 0.83-1.19). Nonsignificant associations were seen between kidney cancer and TCE, lung cancer and hydrazines, and stomach cancer and years worked as a test stand mechanic. No trends over exposure categories were statistically significant. CONCLUSION: Work at the SSFL rocket engine test facility or as a test stand mechanic was not associated with a significant increase in cancer mortality overall or for any specific cancer.

Adult↗

Labeling immunoelectrophoresis: a general method for increasing the sensitivity of rocket immunoelectrophoresis with 125I-labeled anti-antibodies.

In a new procedure, rocket immunoelectrophoresis is performed at pH 8.7 with rabbit antibodies and 5% polyethyleneglycol 6000 in the agarose gel. After the pH in the gel has been changed to 5 the nonprecipitated immunoglobulins are electrophorsed out of the gel simultaneously with the electrophoresis of 125I-labeled swine antibodies against rabbit IgG into the gel. The latter antibodies tag the rabbit IgG, which is not present only in the precipitates. The radioactive precipitates are visualized by autoradiography. The method permits quantification of antigens down to an amount of approximately 0.5 ng; well-defined rockets are not formed below this limit. Compared to conventional protein staining with Coomassie brilliant blue, this represents an increase in sensitivity of up to 20 times.

Antibodies, Anti-Idiotypic↗

Analysis of particle laden flow and heat transfer in cascade and rocket nozzle.

This paper presents results for the calculation of particle trajectories in a cascade and a rocket nozzle using a Lagrangian method. When the floating particles collide to the components, the component surface is damaged severely. The surface erosion rate is strongly dependent on a particle size, a particle impact angle and a surface material. For a compressor cascade, the particle impact rate increases proportionally with the flow inlet angle and the erosion rate on the pressure side surface of blade are related to the surface or coating materials. For a solid rocket nozzle, the particle free zone in the nozzle divergent section increases quickly with increasing particle size and the maximum heat transfer density occurs at the starting region of nozzle convergent section. The Al2O3 droplet breaks up around the nozzle throat due to the high velocity difference between the droplet and gas stream, resulting in the big change of particle free zone.

Journal Article↗

Phosphoenolpyruvate-sugar phosphotransferase transport system of Streptococcus mutans: purification of HPr and enzyme I and determination of their intracellular concentrations by rocket immunoelectrophoresis.

Enzyme I and HPr, the general proteins of the phosphoenolpyruvate-sugar phosphotransferase system, play a pivotal role in the control of sugar utilization in gram-negative and gram-positive bacteria. To determine whether growth conditions could modify the rate of biosynthesis of these proteins in Streptococcus mutans, we first purified to homogeneity enzyme I and HPr from S. mutans ATCC 27352. Using specific antibodies obtained against these proteins, we determined by rocket electrophoresis the intracellular levels of enzyme I and HPr in cells of S. mutans 27352 grown under various batch culture conditions and in a number of glucose-grown cells of other strains of S. mutans. HPr was purified by the procedure reported by Gauthier et al. (L. Gauthier, D. Mayrand, and C. Vadeboncoeur, J. Bacteriol. 160:755-763, 1984) and displayed a single band with a molecular weight of 6,650 when analyzed by sodium dodecyl sulfate-urea gel electrophoresis. Enzyme I was purified by DEAE-cellulose chromatography, affinity chromatography on an anti-Streptococcus salivarius column, and preparative electrophoresis. The protein migrated as a single band in native and denaturating gel electrophoresis. The subunit molecular weight of enzyme I determined by electrophoresis under denaturating conditions was 68,000. In gel filtration chromatography at 4 degrees C, the enzyme migrated as a 135,000- to 160,000-molecular-weight species, suggesting that enzyme I is a dimer. In double immunodiffusion experiments, antibodies against HPr reacted with several oral streptococci, Streptococcus lactis, Streptococcus faecium, and Lactobacillus casei, but not with Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. Antibodies against enzyme I of S. mutans 27352 cross-reacted with enzyme I from all the other oral streptococci tested. No cross-reaction was observed with other gram-positive and gram-negative bacteria. The levels of enzyme I and HPr determined by rocket electrophoresis in S. mutans 27352 varied at the most by twofold, depending on the growth conditions. Glucose-grown cells of other S. mutans strains contained levels of enzyme I and HPr which were similar to those found in S. mutans 27352.

Animals↗

Quantification of the C3 breakdown product C3d by rocket immunoelectrophoresis.

The levels of the C3 breakdown product C3d were measured in plasma, serum, and synovial fluid by the technique of rocket immunoelectrophoresis. Serum and plasma from 22 healthy donors, 4 patients with rheumatoid arthritis, 1 patient with systemic lupus erythematosus, and 1 patient with cryoglobulinemia were used. The synovial fluid was studied in 3 other patients with rheumatoid arthritis. Normal values for the 22 healthy donors in plasma were within a narrow range of 3.25--5.75% as compared to the standard pool that was prepared. Storage of plasma to -80 degrees C during 7--15 days did not modify the results of the test. Significant differences in C3d values were observed between serum and EDTA plasma samples. Patients with immunological diseases showed higher values of C3d in the samples (from 5 to 30% of activity as compared to the standard pool). Measurement of C3d by rocket immunoelectrophoresis showed to be an easy, satisfactory and reliable procedure able to be incorporated to routine immunological evaluations.

Arthritis, Rheumatoid↗

IgG, IgA and IgM by formylated rocket immunoelectrophoresis.

Formylated rocket electrophoresis has been investigated as a means of measuring the serum immunoglobulins IgG, IgA, and IgM. This procedure is simpler to carry out than carbamylation. Comparison of formylated rocket results with those from the automated immunoprecipitin (A.I.P.) system and single radial immunodiffusion (S.R.D.) gives correlation coefficients of 0.92 to 0.98 and reproducibility comparable with the AI.P. system and better than S.R.D. The procedure is recommended for use in laboratories when the number of requests for immunoglobulins does not warrant a specific protein analyser.

Formaldehyde↗

Isolation and structural elucidation of 4-(beta-D-glucopyranosyldisulfanyl)butyl glucosinolate from leaves of rocket salad (Eruca sativa L.) and its antioxidative activity.

A structurally unique glucosinolate (GSL) was identified to be 4-(beta-D-glucopyranosyldisulfanyl)butyl GSL in rocket leaves. The positive-ion electrospray ionization mass spectrometry (ESI-MS) data indicated that the new GSL had a molecular weight of 521 (m/z 522, [M+H](+), as desulfo-GSL). The molecular formula of the substance was determined to be C(17)H(32)O(11)NS(3) (m/z 522.1143, [M+H](+)) based on its positive-ion high-resolution fast atom bombardment mass spectrometry (HR-FAB-MS) data. For the further confirmation, desulfated GSL of 4-(beta-D-glucopyranosyldisulfanyl)butyl GSL was prepared by commercial 1-thio-beta-D-glucose and dimeric 4-mercaptobutyl desulfo-GSL, which was also isolated from rocket leaves, and its chemical structure was then confirmed by MS data and nuclear magnetic resonance (NMR) spectroscopy. In addition, the antioxidative activity of 4-(beta-D-glucopyranosyldisulfanyl)butyl desulfo-GSL was measured by means of chemiluminescence (CL) for evaluating the functional properties. The antioxidative activity (2.089 unit/g) was relatively higher than that of dimeric 4-mercaptobutyl desulfo-GSL (1.227).

Antioxidants↗

Selection of artificial gravity by animals during suborbital rocket flights.

White rats selected preferred artificial gravity levels by locomotion in centrifuges consisting of two runways mounted in the nose of sounding rockets. Roll rate of the Aerobee 150A rocket was designed to produce an angular velocity of 45 r.p.m. during 5 min of free-fall, providing a gravity range range from 0.3 to 1.5 G depending on a subject's runway position. One animal was released at the high and one at the low gravity position in each flight. Animal positions were continuously recorded. Flight subjects were selected from about 100 trained animals adapted to the simulated launch environment for several months. In two flights excessive rollrates produced gravity ranges above the designed limits. In two other flights the desired range was produced. Locomotion patterns during these flights were similar. All four animals explored the entire available G-range. One rat settled at 0.4 G after 2 min; the others crossed the 1-G location in progressively narrower excursions and were near earth gravity at the end of the test period. Data were more varible than in laboratory tests above 1 G and the observation periods were necessarily few and short. Tentatively, however, the data suggest that normal earth-reared rats select earth gravity when available magnitudes include values above and below 1 B. Modification of gravity preference by prolonged exposure to higher or lower levels remains a possibility.

Animals↗

Test of a life support system with Hirudo medicinalis in a sounding rocket.

Two Nike-Tomahawk rockets each carrying two Biosondes were launched from Wallops Island, Virginia, the first on 10 December 1970 and the second on 16 December 1970. The primary objective of both flights was to test the Biosonde life support system under a near weightless environment and secondarily to subject the Hirudo medicinalis to the combined stresses of a rocket flight. The duration of the weightless environment was approximately 6.5 minutes. Data obtained during the flight by telemetry was used to ascertain the operation of the system and the movements of the leeches during flight. Based on the information obtained, it has been concluded that the operation of the Biosondes during the flight was similar to that observed in the laboratory. The experiment and equipment are described briefly and the flight results presented.

Air Conditioning↗

[Psychomotor reaction in primates placed in ballistic flight in rockets].

Psychomotor reactions have been studied in Nemestrina Macaques during flights in rockets in which there were periods of weightlessness lasting about 10 minutes. The animals had undergone motor conditioning and responded to a light signal by pressing on a button placed on a panel where there were four other undifferentiated buttons. The lighting of the panel and pressing on the different buttons in reply was recorded with respect to time. Movement was observed by film recording, and electrical activity of the brain was kept under observation by six different recordings of the cortex. Activity of stretching and bending muscles of the legs was recorded, as well as breathing, and heart activity was recorded on an electrocardiogram. These psychological parameters were transmitted to the earth by long-distance measurement during the entire flight. The recordings made it possible to confirm that the absence of the sensation of weight seems to reduce the alertness of the animals. This fact had already been observed in Wistar's rat and cat. The sensor-psychomotor responses undergo important individual variations and depend on the motivation of the subjects. A very well motivated one reacted after a short period of adaption, as it did in the laboratory: one that was much less motivated would not work until after weightlessness has ended, and showed signs of drowsiness. These observations made during the flights in rockets confirm those of Chambers et al., Harris et al., Lilly et al. made in immersion studies; they show the important role of weight in maintaining alertness, but that changes of psychomotor activity are particularly related to motivation.

Animals↗