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Automatic fixation facility for plant seedlings in the TEXUS Sounding Rocket Programme.

Automatic chemical fixation of plant seedlings within a 6 min period of reduced gravity (10(-4)g) was performed on three ballistic rocket flights provided by the German Sounding Rocket Programme TEXUS (Technologische Experimente unter Schwerelosigkeit = Technological Experiments in Microgravity). The described TEXUS experiment module consists of a standard experiment housing with batteries, cooling and heating systems, timer, and a data recording unit. Typically, 60 min before launch an experiment plug-in unit containing chambers with the plant material, the fixation system, and the temperature sensors is installed into the module which is already integrated in the payload section of the sounding rocket (late access). During the ballistic flight plant chambers are rapidly filled at pre-selected instants to preserve the cell structure of gravity sensing cells. After landing the plant material is processed for transmission electron microscopy. Up to now three experiments were successfully performed with cress roots (Lepidium sativum L.). Detailed improvements resulted in an automatic fixation facility which in principle can be used in unmanned missions.

Acceleration↗

The survival of micro-organisms in space. Further rocket and balloon-borne exposure experiments.

This report describes the results of survival studies of terrestrial micro-organisms exposed directly to the space environment on two balloons and in two rocket flights. The work is part of a program to develop techniques for the collection of micro-organisms in the size range of micrometeorite particles in space or non-terrestrial atmospheres, and their return to earth in a viable state for further study. Previous survival studies were reported (J. Hotchin, P. Lorenz and C. Hemenway, Nature 206 (1965) 442) in which a few relatively large area samples of micro-organisms were exposed on millipore filter cemented to aluminum plates. In the present series of experiments, newly developed techniques have resulted in a 25-fold miniaturization resulting in a corresponding increase in the number of experiments performed. This has enabled a statistical evaluation of the results to be made. A total of 756 separate exposure units (each approximately 5 x 5 mm in size) were flown in four experiments, and organisms used were coliphage T1, penicillium roqueforti (THOM) mold spores, poliovirus type I (Pfizer attenuated Sabin vaccine strain), and bacillus subtilis spores. The organisms were deposited either by spraying directly upon the vinyl-coated metal units, or by droplet seeding into shallow depressions in the millipore filter membrane-coated units. Groups of units were prepared comprising fully exposed, inverted (screened by 2 mm of Al), and filter-protected organisms. All of these were included in the flight set, the back up set, and a laboratory control set. The altitude of the exposures varied from 35 km in the balloon experiments to 150 km in the rocket experiments. Times of exposures at altitude were approximately 6 hours for the balloon flights and about 3 minutes for the rocket experiments.

Altitude↗

Survivability and injuries from use of rocket-assisted ejection seats: analysis of 232 cases.

INTRODUCTION: Ejection injury has been documented with respect to non-rocket-assisted seats, but there is little information on injuries associated with rocket-assisted seats. This study analyses the survivability of military accidents and the injuries associated with rocket-assisted ejection. METHODS: A total of 232 Royal Air Force accident reports were accessed and aircrews' injuries were related to the aircraft parameters of ejection, aircrew anthropometry, and the ejection seat and parachute dynamics. Ejection sequences were simulated using a computerized modeling tool to provide information relating to the dynamic response index, acceleration of the ejection seats, and performance of the parachutes. RESULTS: Ejection survival was 89.2% overall, 95.7% for within envelope ejections and 23.8% for out of envelope ejections. There were 29.4% of aircrew who sustained spinal fractures. Another 14.2% of aircrew sustained a head injury and the incidence of head injury in Tornado ejectees was higher than the other aircraft types. Compared with 5.8% of ejectees from aircraft with an arm restraint system, 11.2% of aircrew sustained upper limb flail injuries from ejecting from aircraft without an arm restraint system. Arm flail injuries occurred at a higher aircraft speed at ejection compared with ejections where no arm flail injuries were sustained. There was also 18% of aircrew who sustained lower limb parachute landing injuries. DISCUSSION: Information from this study has lead to a redesign of the Tornado ejection seat headbox, an improvement in the Tornado ejection catapult dynamics, an upgrade of escape system parachutes, and provided evidence that future aircraft should be fitted with an arm restraint system.

Accidents, Aviation↗

The rockets' red glare, the bombs bursting in air: fireworks-related injuries to children.

OBJECTIVE: To describe the epidemiology of fireworks-related injuries to children treated in a pediatric emergency department. DESIGN: A descriptive study of a consecutive series of patients. SETTING: The emergency department of a large urban children's hospital. PARTICIPANTS: Children treated for injuries associated with fireworks during the 22-year period from 1972 through 1993. RESULTS: Three hundred sixteen children were treated for fireworks-related injuries. Ninety-five percent of patients were injured during the 3-week period of June 22 to July 14 during the study years. Seventy-one percent of patients were male, and the average age was 8.5 years, with a range of 1 month to 17 years. The child was a bystander in 26% of cases, and adult supervision was present in 54% of cases. One patient died, and 11% of children required admission to the hospital, with an average length of stay of 7.8 days (range, 1 to 37 days). Fifteen children (5%) went to the operating room for treatment of injuries. Thirty-three patients (10%) had permanent sequelae from their injuries, including 7 children (2%) with complete or partial loss of vision in one eye. The eyes were injured in 29% of cases, followed by hands and fingers (22%), other head and face sites (18%), and lower extremities (16%). The primary injury was a burn in 72% of cases. Firecrackers were associated with 42% of injuries, followed by bottle rockets (12%), other types of rockets (7%), Roman candles (11%), sparklers (7%), fountains (5%), jumping jacks (4%), and class B (illegal) fireworks (4%). Sixty-seven percent of sparkler-related injuries occurred among children 5 years and younger (Fisher's exact test, P = .000002; odds ratio [OR] = 10.00, 95% confidence interval 3.52 < OR < 29.24). Permanent sequelae were more common for eye injuries caused by rockets than eye injuries caused by other types of fireworks (Fisher's exact test, P = .03; OR = 6.72, 95% confidence interval 1.18 < OR < 38.18). Charges for medical care of a fireworks-related injury averaged $1385 per patient (range, $44 to $15 071). CONCLUSIONS: Fireworks are associated with serious injuries. Findings of this large consecutive series describe the epidemiology of these injuries. Children and their families should be encouraged to enjoy fireworks at public fireworks displays conducted by professionals. Fireworks for individual private use should be banned.

Adolescent↗

Actin-based endosome and phagosome rocketing in macrophages: activation by the secretagogue antagonists lanthanum and zinc.

Although motile endocytic vesicles form actin-rich rocket tails [Merrifield et al., 1999: Nature Cell Biol 1:72-74], the mechanism of intracellular organelle locomotion remains poorly understood. We now demonstrate that bone marrow macrophages treated with lanthanum and zinc ions, well-known secretagogue antagonists, reliably exhibit vesicle motility. This treatment results in accentuated membrane ruffling and the formation of phagosomes and early endosomes that move rapidly through the cytoplasm by assembling actin filament rocket tails. Protein-specific immunolocalization demonstrated the presence of Arp2/3 complex in the polymerization zone and throughout the actin-rich tail, whereas N-WASP was most abundant in the polymerization zone. Although Arp2/3 and N-WASP play essential roles in nucleating filament assembly, other processes (i.e., elongation and filament cross-linking) are required to produce forces needed for motility. Efficient elongation was found to require zyxin, VASP, and profilin, proteins that interact by means of their ABM-1 and ABM-2 proline-rich motifs. The functional significance of these motifs was demonstrated by inhibition of vesicle motility by the motif-specific ABM-1 and ABM-2 analogues. Furthermore, lanthanum/zinc treatment also facilitated the early onset of actin-based vaccinia motility, a process that also utilizes Arp2/3 and N-WASP for nucleation and the zyxin-VASP-profilin complex for efficient elongation. Although earlier studies using cell extracts clouded the role of oligoproline sequences in activating the polymerization zone, our studies emphasize the importance of evaluating motility in living cells.

Actin-Related Protein 2↗

Listeria's right-handed helical rocket-tail trajectories: mechanistic implications for force generation in actin-based motility.

Listeria monocytogenes forms right-handed helical rocket tail trajectories during actin-based motility in cell-free extracts, and this stereochemical feature is consistent with actoclampin's affinity-modulated, clamped-filament elongation model [Dickinson and Purich, 2002: Biophys J 82:605-617]. In that mechanism, right-handed torque is generated by an end-tracking molecular motor, each comprised of a filament barbed end and clamping protein that processively traces the right-handed helix of its filament partner. By contrast, torque is not a predicted property of those models (e.g., elastic propulsion, elastic Brownian ratchet, tethered ratchet, and insertional polymerization models) requiring filament barbed ends to depart/detach from the motile object's surface during/after each monomer-addition step. Helical trajectories also explain why Listeria undergoes longitudinal-axis rotation on a length-scale matching the helical periodicity of Listeria's rocket tails.

Actins↗

Enzyme activity electrophoresis and rocket immunoelectrophoresis for the qualitative and quantitative analysis of Geotrichum candidum lipase activity.

The development and application of a rocket immunoelectrophoretic and an enzyme activity electrophoretic assay for the qualitative analysis of Geotrichum candidum lipase activity is presented. The sensitivities of the four assays were (in arbitrary units): enzyme activity electrophoresis, 1-0.5; rocket immunoelectrophoresis, 0.5-0.2; radial diffusion, 1; titrimetry, 1. The electrophoretic methods made it possible to distinguish between high and low molecular weight forms of the G. candidum lipases. The enzyme activity electrophoretic methods can be combined with other electrophoretic techniques, as demonstrated here with isoelectric focusing, and produce useful information on physico-chemical differences between different molecular forms of the lipase, e.g. forms with different pI.

Geotrichum↗

Quantitative determination of individual glycosaminoglycans in plasma by concanavalin A rocket electrophoresis.

A new one-dimensional agarose gel electrophoresis method for the quantitation of glycosaminoglycans in biological samples has been described. In this procedure, concanavalin A, suspended in agarose gel, interacts with glycosaminoglycans such that rocket-like precipitin lines are formed. The area of the rocket is directly proportional to the glycosaminoglycan content of the sample. This procedure permits measurement of glycosaminoglycans in amounts as low as 0.5 nmol uronic acid equivalents with a coefficient of variation of only 8%. The described method has been applied to the determination of free heparan sulfate in plasma. This method can also be used to measure all high-charge glycosaminoglycans of biological interest.

Animals↗

Quantitation of human intestinal and liver/bone alkaline phosphatase in serum by rocket electroimmunoassay.

The separation and quantitation of the various human serum alkaline phosphatases has been largely by indirect and/or imprecise methods. A rocket electroimmunoassay method has been developed for the quantitation of the alkaline phosphatases, which uses enzymatic activity to detect the rocket and bromochloroindolylphosphate as substrate. The assay for intestinal phosphatase requires only one-dimensional electrophoresis, since the antibody to the intestinal enzyme does not cross-react with the other phosphatases. Both liver and bone enzymes give a line of identity when tested against antibody directed against the liver phosphatases, and these phosphatases require separation first by acrylamide gel electrophoresis before quantitation by crossed immunoelectrophoresis. Liver/bone enzyme levels in serum are easily detected within the linear range of the assay without concentration of the serum. The assay is 10-fold more sensitive than quantitation by acrylamide gel electrophoresis. The inability to detect circulating intestinal alkaline phosphatase in the serum of most fasting hospitalized patients has been documented by this sensitive assay, and the predominance of the liver isoenzyme has been confirmed. The assay should prove useful for determining the tissue of origin of serum alkaline phosphatases, and in providing quantitative data for physiological studies. It is not adaptable for automation and will not prove useful in the routine clinical laboratory.

Alkaline Phosphatase↗

Determination of pepsin (EC 3.4.23.1) and gastricsin (EC 3.4.23.3) in gastric juice by rocket immunoelectrophoresis.

Antisera were raised in rabbits against chromatographically purified preparations of pepsin and gastricsin. With these antisera the contents of pepsin and gastricsin in gastric juice were determined by rocket immunoelectrophoresis. The potential content of pepsin and gastricsin of a secondary standard of gastric mucosal extract was calibrated against the chromatographically purified enzymes. This secondary standard was used for routine analyses. The intra-assay and between-assay precision was 3-4% and 6-9%, respectively. Ten healthy volunteers underwent a standard pentagastrin test. The amounts of pepsin and gastricsin determined by rocket immunoelectrophoresis corresponded to the amounts observed by ion exchange chromatography of gastric juice. After stimulation with pentagastrin the secretion of both pepsin and gastricsin was increased about 10 times.

Adult↗

Quantitation of diphtheria and tetanus antibodies by reversed rocket immunoelectrophoresis.

A reversed rocket immunoelectrophoresis technique, applying serum samples to antigen-containing gel, is described for quantitation of human antibodies to diphtheria and tetanus. Lowering of the pH of the buffer from 8.6 to 5.2 increased the height of the rockets, but also resulted in more non-specific precipitation. This smudging could be removed by dextran sulphate precipitation of the sera, a necessity when quantitating sera with small concentrations of anti-bodies. The merits of this method are discussed in relation to other in vitro as well as in vivo methods. The method was found to be reproducible, rapid, cheap and sensitive, and to require small samples of serum.

Animals↗

Rocket immunoelectrophoresis in the presence of denaturing agents.

Modifications of the Laurel rocket technique for assaying antigen antibody reactions are described. These procedures allow insoluble proteins to be dissolved in a variety of denaturing solvents (e.g., SDS and urea) and subjected to electroimmunoassay without loss of sensitivity or specificity. Methods are also presented for obtaining rockets using gel slices from polyacrylamide gel electrophoresis either in the presence of urea or SDS. Results obtained using keratins, the insoluble proteins of epidermis, hair and nail are summarized.

Animals↗

Determination of IgG and IgM levels in serum by rocket immunoelectrophoresis using yolk antibodies from immunized chickens.

A method of rocket immunoelectrophoresis based on the use of avian antiglobulin antibodies is described which permits the quantitation of IgG and IgM in human serum. The electrophoretic mobility of avian yolk immunoglobulin (IgY) and mammalian IgG is sufficiently different to obviate the need to chemically modify the antibody, for example by carbamylation. Rockets are obtained in agarose within 3-6 h in 2-(N-morpholino) ethane sulfonic acid buffer at pH 5.5 or 6.0. Avian globulins specific for human IgG and IgM were obtained easily and in large quantities from the egg yolk of hyperimmunized laying hens. The technique is also applicable to quantitation of immunoglobulins in various animal sera.

Animals↗

Quantitative estimation of diphtheria and tetanus toxoids. 2. Single radial immuno-diffusion tests (Mancini) and rocket immuno-electrophoresis test in comparison with the flocculation test.

The concentration in Lf units, of an unknown diphtheria or tetanus toxoid preparation is estimated in the flocculation test relative to reference preparations of tetanus and diphtheria antitoxins, respectively. By replacing the antitoxin reference preparations with toxoid reference preparations it should be possible to use immunological methods other than the flocculation test for the quantitative estimation of toxoids in Lf units. A number of diphtheria and tetanus toxoids were tested by rocket immuno-electrophoresis and single radial immuno-diffusion (Mancini test). The concentrations of the unknown toxoids were expressed relative to a diphtheria toxoid calibrated in Lf units (DIFT) and a tetanus toxoid calibrated in Lf units (TEFT), respectively. These two toxoid preparations are regarded as candidates for establishment as international standard preparations. The results obtained in the two tests were compared with those obtained in the flocculation test. In most cases the differences between the results did not exceed 10%. It is concluded, therefore, that the rocket electrophoresis or the radial immuno-diffusion tests can be used as alternatives to the flocculation test.

Diphtheria Toxoid↗

Fertilization of frog eggs on a Sounding Rocket in space.

During the TEXUS-17 flight (April/May 1988) eggs of a higher organism, the anuran amphibian Xenopus laevis, have for the first time been successfully fertilized under microgravity on a Sounding Rocket. This result also implies that Life Sciences Experiments of Short Duration can be carried out on Sounding Rockets. The latter can therefore function as additional carriers for such experiments. Histological sections of the experimental material demonstrated the penetration of sperm into eggs, while SEM analysis revealed the differentiation of characteristic egg surface structures. Our TEXUS-17 experiment convincingly shows that the modified automatic experiment container, originally designed for experimental BR 52NL on the D1-mission, now functions flawlessly. Eight containers were flown in an airtight, well-isolated box (TEM 06-15), and a similar set was activated on Earth, two hours later. The analysis of the biological material is in progress.

Animals↗

Singular case of shooting a football fan with a signal rocket.

The authors present a very rare case of fatal injuries resulting from shooting a parachute signal rocket with a hand operated launcher of signal pistol kind by pseudo-football fans. A 16-year-old football fan sustained extensive thermal burn of his lower extremities and abdomen, lacerated wound of his left thigh with a deep signal rocket-shot canal which caused injuries in subcutaneous tissue, fascia and both medial and posterior muscles of the thigh as well as injured both femoral vein and artery with subsequent hemorrhagic, burn and traumatic shocks. In spite of specialistic surgical treatment, the victim was not rescued. Analysis of medical documentation and our autopsy results were supplemented with an expert's opinion on physicochemical examinations supported by photographic documentation.

Abdominal Injuries↗

Effectiveness of household natural sanitizers in the elimination of Salmonella typhimurium on rocket (Eruca sativa Miller) and spring onion (Allium cepa L.).

Experiments were done with fresh lemon juice, vinegar and their mixture (1:1) to evaluate their efficacy in reducing the numbers of Salmonella typhimurium on fresh salad vegetables. Fresh whole rocket leaves and shredded spring onion samples were inoculated with S. typhimurium suspensions to provide initial populations of approximately 6 and 3 log cfu/g. After inoculation, vegetables were treated with the test solutions for 0, 15, 30 and 60 min, and pathogens were enumerated by using direct plating on Bismuth Sulphite Agar (BSA). Prior to this work, it was shown that BSA was not toxic for acid injured Salmonella cells by statistical analysis applied to enriched and non-enriched samples (P>0.05). Treatment of rocket leaves with fresh lemon juice and vinegar caused a significant reduction ranging between 1.23 and 4.17 log cfu/g and between 1.32 and 3.12 log cfu/g, respectively, while the maximum reduction reached by using lemon juice-vinegar mixture (1:1) for 15 min, which reduced the number of pathogens to an undetectable level. In the spring onion samples, lemon juice, vinegar and their mixture caused 0.87-2.93, 0.66-2.92 and 0.86-3.24 log cfu/g reductions, respectively.

Acetic Acid↗

Effects of roxifiban on platelet aggregation and major receptor expression in patients with coronary artery disease for the Roxifiban Oral Compound Kinetics Evaluation Trial-I (ROCKET-I Platelet Substudy).

BACKGROUND: It has been expected that therapy with oral glycoprotein (GP) IIb/IIIa blockers including roxifiban will reduce mortality and vascular complications in a long-term. However, platelet-related properties of roxifiban in the clinical setting are not well known. We measured platelet characteristics during chronic treatment in patients with coronary artery disease enrolled in the Roxifiban Oral Compound Kinetics Evaluation Trial (ROCKET-I). METHODS: ROCKET-I was designed as a randomized, double blind, multicenter, dose-ranging study of roxifiban, administered either as monotherapy or concomitantly with aspirin, compared with aspirin alone. Thirty-one patients were assigned for 24 weeks of therapy with aspirin (n = 7), roxifiban (n = 9), or roxifiban plus aspirin (n = 15). Platelets were assessed 5 times in each patient at baseline, and at weeks 2, 4, 12, 18, and 24 thereafter with aggregometry and flow cytometry. RESULTS: Baseline platelet characteristics were similar in all 3 groups. There was a consistent significant decrease of adenosine diphosphate- (P =.0001) and collagen-induced (P =.002) platelet aggregation in the patients treated with roxifiban when compared with patients treated with aspirin alone. Flow cytometry revealed paradoxical late activation of GP IIb/IIIa expression (P =.007) when roxifiban was used without aspirin, which was significant compared with the aspirin and aspirin-roxifiban groups. There were no differences among groups in GP Ib expression, although its rise was more profound in the patients treated with roxifiban. There were substantial differences in the P-selectin expression. Although aspirin time dependently decreased the percent of P-selectin positive platelets (P =.02), treatment with roxifiban resulted in the phasic changes with the early inhibition (P =.01) and then 2-fold activation (P =.0001) starting at week 12 of the therapy. There was an early transient activation of platelet endothelial cell adhesion molecule-1 expression (P =.008) at week 2, followed by the later inhibition of this receptor (P =.003) in patients treated with roxifiban. CONCLUSION: Despite achieving sustained inhibition of platelet aggregation, therapy with roxifiban has been associated with over expression or phasic changes of major platelet receptors. These data may explain clinical concerns about the use of oral GP IIb/IIIa inhibitors linking higher mortality rates and incidence of thrombotic episodes with paradoxical switching to alternative passways of platelet activation.

Amidines↗