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The purpose of this study was to follow up the changes in antioxidative adaptive mechanisms induced by various periods of small intestinal ischemia in Wistar rats. The superior mesenteric artery was occluded for 15, 30, 45, 60 and 90 min. After the respective ischemic intervals, a reperfusion was set for 120 min. Samples of the serum and intestinal mucosa were taken at the end of ischemia or at the end of reperfusion. Total radical-trapping antioxidant parameter (TRAP) of the serum and the oxidative burst of neutrophils were evaluated using luminol-enhanced chemiluminescence. Individual antioxidants in the serum and the concentration of thiobarbituric acid reactive substances (TBARs) in both serum and intestinal mucosa were measured spectrophotometrically. Increased activation of circulating neutrophils was found after the reperfusion irrespective of the duration of ischemia. TRAP of the serum was increased at the end of the ischemia lasting from 30 to 90 min. This effect was further enhanced by the subsequent reperfusion period. Ascorbate and urate contributed considerably to the TRAP value especially after reperfusion following 60 and 90 min of ischemia. On the other hand, no significant changes in albumin and bilirubin serum concentrations were observed. Contrary to the mobilized antioxidative mechanisms, increased lipid peroxidation was observed in both serum and mucosa samples.

In recent years, microsensor technologies have made a rapid expansion into different fields of physical sciences, engineering, and biomedicine. For analyses of various biomolecules, novel sensors and detection platforms in the electrochemical field have been reported recently. The most important applications based on microelectromechanical systems dramatically reduce the need of manipulation steps with samples, while improving data quality and quantitative capabilities. This is also the case of a special class of electrochemical sensors that allow direct, real-time and non-invasive measurements of nitric oxide, whose determination is crucial for the purposes of basic research, as well as of preclinical and clinical studies. Therefore, this minireview will focus on the description of recent discoveries in the electrochemical determination of nitric oxide, released in different in vitro systems.

Controlled production of reactive oxygen species (ROS) by NADPH oxidases in non-phagocytic cells has recently been suggested to participate in the regulation of cellular functions. Due to the role of ROS in control of cellular functions, precise and accurate detection of ROS is of essential importance. However, various methodological approaches currently used for ROS determination vary in sensitivity, specificity, as well as in requirements for specialized equipment. In this study, human lung epithelial cell line A549 was screened for expression of NADPH oxidases NOX1, NOX2, NOX4, NOX5, DUOX1 and DUOX2 by quantitative RT-PCR. Fluorometric, colorimetric, and chemiluminometric methods were applied to determine ROS production. A549 cells were found to significantly express NOX1, NOX2, DUOX1 and DUOX2. ROS production by A549 cells was detected with fluorometric probes 2',7'-dichlorofluorescein- diacetate, dihydroethidium, and amplex red or colorimetric probe nitrobluetetrazolium. The production of ROS detected by these probes was partially reduced by NADPH oxidase inhibitor diphenyleneiodonium. The inhibitory effect of diphenyleneiodonium was the most significant regarding amplex red detection of phorbol myristate acetateactivated ROS production. In contrast to other probes, neither cytochrome c colorimetric determination nor luminol- and L-012-amplified chemiluminescence, regardless of the addition of horseradish peroxidase, exerted sufficient sensitivity to detect ROS production by A549. The results revealed differences among methods used for ROS formation measurement by human lung epithelial cell line A549 and highlighted the sensitivity of fluorometric determination for this purpose.

The assay employing firefly luciferase as the end-point reporter is one of the most popular gene reporter systems. However, the physiological conditions of cells may affect the reporter gene expression, which makes an assessment of cell viability desirable. Estimates of cell viability may be based on different principles. We tested for correlations between various cell viability assessments, including luminescent determination of adenosine triphosphate in whole-cell lysate, and the reporter luciferase activity in pluripotent embryonic and colon adenocarcinoma cells. Luciferase activity in cell lysate from both cell lines cultured under different conditions correlated with the amount of viable cells assessed by all of the methods employed. Importantly, it was also possible to carry out adenosine triphosphate determination in cell lysates prepared in the buffer originally designed for determining luciferase activity; it correlated significantly with adenosine triphosphate determination in cells lysed in the buffer originally designed for adenosine triphosphate determination. The results suggest that the assessment of live cells by determining adenosine triphosphate can be multiplexed with a luciferase reporter gene assay, which allows independent monitoring of both reporter expression and cell viability.

The interaction of adrenergic agonists and/or antagonists with the adrenergic receptors expressed on immunologically active cells including macrophages plays an important role in regulation of inflammatory responses. Our study investigated the effects of carvedilol, a unique vasodilating beta-adrenergic antagonist, and endogenous adrenergic agonists (adrenalin, noradrenalin, and dopamine) and/or antagonists (prazosin, atenolol) on lipopolysaccharide-stimulated nitric oxide (NO) production from murine macrophage cell line RAW 264.7. The production of NO was determined as the concentration of nitrites in cell supernatants (Griess reaction) and inducible nitric oxide synthase (iNOS) protein expression (Western blot analysis). Scavenging properties against NO were measured electrochemically. Carvedilol in a concentration range of 1, 5, 10 and 25 microM inhibited iNOS protein expression and decreased the nitrite concentration in cell supernatants. Adrenalin, noradrenalin or dopamine also inhibited the iNOS protein expression and the nitrite accumulation. Prazosine and atenolol prevented the effect of both carvedilol and adrenergic agonists on nitrite accumulation and iNOS expression in lipopolysaccharide-stimulated cells. These results, together with the absence of scavenging properties of carvedilol against NO, imply that both carvedilol and adrenergic agonists suppress the lipopolysaccharide-evoked NO production by macrophages through the activation and modulation of signaling pathways connected with adrenergic receptors.

LIF is a cytokine playing a key role in the regulation of self-renewal and maintenance of undifferentiated state in mouse ES cells. The response of pluripotent cells to LIF is mediated mainly by the STAT3 and ERK signalling pathways. Recently, we have shown that LIF potentiated retinoic acid-induced neural differentiation of pluripotent mouse embryonal carcinoma P19 cells. Here we demonstrate that pro-neural effects of LIF and partially also of retinoic acid are abolished by inhibition of the JAK2-STAT3 signalling pathway. In contrast, inhibition of the MEK1-ERK signalling pathway does not exhibit any effect. These results suggest that in neurogenic regions, cooperative action of LIF and other neuro-differentiation-inducing factors, such as retinoic acid, may be mediated by the STAT3 signalling pathway.

The purpose of this study was to follow up the changes in antioxidative adaptive mechanisms induced by various periods of small intestinal ischemia in Wistar rats. The superior mesenteric artery was occluded for 15, 30, 45, 60 and 90 min. After the respective ischemic intervals, a reperfusion was set for 120 min. Samples of the serum and intestinal mucosa were taken at the end of ischemia or at the end of reperfusion. Total radical-trapping antioxidant parameter (TRAP) of the serum and the oxidative burst of neutrophils were evaluated using luminol-enhanced chemiluminescence. Individual antioxidants in the serum and the concentration of thiobarbituric acid reactive substances (TBARs) in both serum and intestinal mucosa were measured spectrophotometrically. Increased activation of circulating neutrophils was found after the reperfusion irrespective of the duration of ischemia. TRAP of the serum was increased at the end of the ischemia lasting from 30 to 90 min. This effect was further enhanced by the subsequent reperfusion period. Ascorbate and urate contributed considerably to the TRAP value especially after reperfusion following 60 and 90 min of ischemia. On the other hand, no significant changes in albumin and bilirubin serum concentrations were observed. Contrary to the mobilized antioxidative mechanisms, increased lipid peroxidation was observed in both serum and mucosa samples.

Cytokines play a major role in the control of inflammatory responses, participate in the regulation of blood phagocyte activities and as such are used for immunomodulatory therapy. In the present study, the influence of IL-10 on human blood phagocyte activity in the presence/absence of IL-6, IL-8 and TNF-alpha was tested in vitro. Our research analyzed the effects of cytokines on the production of reactive oxygen species measured by chemiluminescence and flow cytometry, and on the expression of surface molecules (CD11b, CD15, CD62L, CD31) measured by flow cytometry. IL-10 had no inhibitory effect on reactive oxygen species production and the expression of any examined adhesion molecule by resting or stimulated blood phagocytes within 3 h of incubation. Conversely, TNF-alpha, IL-6, and IL-8 increased reactive oxygen species production and the expression of CD11b and CD15 on both neutrophils and monocytes and decreased the expression of CD62L. These priming effects of the tested pro-inflammatory cytokines were not affected by IL-10. The obtained results suggest that IL-10 does not directly control blood phagocyte activation. These results also provide better information about the contribution of IL-6, IL-8 and TNF-alpha to the regulation of blood phagocyte-mediated inflammatory processes.

The luminol-enhanced chemiluminiscence method was used to investigate the antioxidative activity of N-(alkoxyphenyl)-2-(2-oxo-1-aza-1-cykloalkyl) acetamides studied as potential cognitive enhancers and stobadine acylderivatives which form prodrugs with increased lipophilicity. The effect on the production of reactive oxygen metabolites by activated leukocytes was studied in vitro. Furthermore, the total radical-trapping antioxidant parameter was evaluated as the peroxyl radical-trapping capacity and the scavenging effect on the superoxide anion radical (generated by the enzymatic system hypoxanthine/xanthine oxidase) and on the hydroxyl radical (produced in Fenton reaction) were studied. The antioxidative properties of the tested substances were compared with that of stobadine dihydrochloride. Only stobadine and its butyrylderivative have been demonstrated to possess free radical scavenging activity in all systems. Cinnamoylstobadine inhibited only the leukocyte chemiluminiscence activity. The potential cognitive enhancers did not show any antioxidant activity.

The aim of the study was to compare the effect of hemophane and polysulfone membranes on the phagocyte-derived production of reactive oxygen species (ROS) as well as on neutrophil CD11b and CD62L expression in patients undergoing regular hemodialysis. The effects of hemodialysis membranes were also studied in in vitro conditions after coincubating them with differentiated HL-60 cells. ROS production was measured using chemiluminometric and flow cytometric methods. Expression of CD11b, CD62L and mitochondrial membrane potential were detected by monoclonal antibodies and by the JC-1 fluorescent probe, respectively. Depressed ROS production was observed in patients already before dialysis. Further decrease in ROS production and an increase in CD11b expression were observed especially in patients after hemophan hemodialysis. Decreased ROS production and increased CD11b expression were observed also after incubation of HL-60 cells with hemophan membranes. Mitochondrial membrane potential dropped only after incubating cells with hemophan membranes proving its more serious adverse effects in comparison with the polysulfone membrane. In conclusion, deleterious effects of hemodialysis on the metabolic activity of phagocytes were proved. Combining chemiluminescent and flow cytometric methods for the detection of ROS production and determining mitochondrial membrane potential can be useful tools for the analysis of material biocompatibility.

Primary focal or segmental glomerulosclerosis is neuropathy diagnosed in 10% of children and 20% of adult patients with nephrotic syndrome. Immunosuppressive therapy was applied during two years period. The very good clinical results were obtained in 20% and good results in 40% of patients after indomethacin and dipyridamole therapy.

An investigation of figural after-effects as affected by hue is described. The brightnesses of an orange, a blue, and a gray were equated by psychophysically determined heterochromatic brightness matches. The use of a standard source of illumination facilitated calculation of tristimulus values and Munsell notation of the stimuli. Although there were no significant differences in after-effects between the chromatic stimuli, each of the chromatic stimuli produced greater displacements than the achromatic stimulus.

(1960). Nutritional Factors in Psychological Test Behavior. The Journal of Genetic Psychology: Vol. 96, No. 2, pp. 343-352.

Reduced-scale techniques were used to determine the actual ranges at which various features of vehicles can be recognized. The principal findings were: A number of recognition features stresses in current training programs were not seen until the observer was very close to the target (number of road wheels and gun tubes, sprocket location, and number of rollers, for example). The determination of turret shape, a major recognition feature, occurred earlier for the bowl shaped turrets than for other shapes. This type of turret is used more often on Soviet type vehicles than on NATO vehicles. The only features seen at scaled distances greater than 1200 meters were (a) tracked vs, wheeled, (b) presence of a turret, and (c) turret location. All other features were seen at closer distances. The detection ranges for features did not appear to be related to amount of prior experience, but seemed to depend on the observer's risk- taking propensity.

This report describes an analysis of the human factors characteristics of the Joint Tactical Fusion Test Bed-Army (JTFTB-A). Data were obtained from interviews, questionnaires, direct observation and physical measurements of the operator stations and environmental factors. An attempt was made to relate the findings to anticipated requirements for an All Source Analysis System (ASAS) for intelligence data. Operators gave high ratings to the large majority of the individual functions the system could perform. However, four functions were rated poorly because operators felt performance time was excessive and procedures were overly tedious.

The primary purpose of this report is to describe the current status of symbology development for use in interactive graphic display systems such as the Command and Control Interactive Display Experimentation System (CCIDES). A secondary purpose is to examine user requirements for such systems when employed as a part of a Tactical Operations System (TOS). An extensive literature survey indicated a great variety of available alternative symbology formats. Before a specific format is selected, the necessary information requirements for a particular position must be determined. For Army tactical displays, this information should be gathered in experiments using realistic battle scenarios. As a related effort, alternative symbol formats were evaluated by civilians. Naive subjects generally preferred a pictorial symbol over traditional military alternatives. The report is written for a military audience.

This report summarizes the resulting five research projects conducted between March 1979 and February 1980. Separate, more detailed reports describing the work in each of the five areas are being published concurrently. These reports are: 'Preliminary Development of the Commander's Unit Analysis Profile: A Leadership Tool for the Small Military Unit'; 'The Impact of Adopting Physical Fitness Standards on Army Personnel Assignment: A Preliminary Study; Testing and Training Methods for Skill Qualification Testing'; 'Reading Ability and Other Correlates of the SQT Written Component'; 'Development of a Basic Training Program in Combat Vehicle Identification'; and 'Improvement of Training Realism for Tactical Units: Opposing Force (OPFOR) Program.

The research requirement was to develop a standard, general-purpose target presentation methodology that could be employed to evaluate visual target acquisition equipment in future US Army field tests. As a first step in this developmental effort, a review of the military and psychological literature was conducted to collect the information pertaining to the factors important in the target acquisition process and threat targets and tactics likely to be encountered on the modern battlefield. Following the review of the literature, the information collected on these topics was integrated into a target presentation methodology.

This report describes the development and evaluation of prototype hands-on equipment, job sample performance tests for a high skilled technical Military Occupation Specialty. An electronic maintenance MOS (26C20) was used as the research vehicle. The results lead to the conclusion that valid and reliable performance tests could be constructed, but that equipment, facilities, and standardization requirements reduce the feasibility of their use at other than ideal location, such as a U.S. Army school.

This report summarizes, for a military audience, work on seven research projects: (a) Target Handoff Techniques, (b) Tank Crew Measures of Effectiveness (MOE), (c) Fatigue Effects of CAV NAV Goggle Use, (d) Long Range Target Recognition, (e) Effects of Stress on Performance, (f) Symbology for Automated Graphic Displays, and (g) Suppression Research. There are separate reports for each of these seven areas. An eighth report briefly describes a technique for developing imagery for target handoff and target identification training. (Author)

This report reviews selected literature on psychological and physiological stressors which affect the soldier in combat. The selections were oriented toward: (a) documents which describe the types of stressors which are likely to be encountered on the battlefield, and (b) documents which describe performance during or following stressful experiences.

This report summarizes five research efforts conducted between May 1976 and May 1977 at Fort Hood, Texas and dealing with aspects of the field assessment of human performance factors in developmental military systems. Separate reports provide more detail for each effort: (1) Study of target Handoff Techniques, ARI TR-78-A34, investigated the verbal interchange in simulated ground-to-air and air-to-ground target handoffs. (2) A Study of Selected Problems in Armor Operations, ARI TR-78-A35, investigated target acquisition performance and internal temperatures in buttoned-up tanks; escape modes; and crew effectiveness measures. (3) Problems in Helicopter Gunnery, ARI TR-78-A36, investigate distance recognition of target vehicles. (4) Statistical Analysis of the Fort Hood Quality-of-Life Questionnaire, ARI Research Memorandum 78-25, tabulated variables, analyses, and computer correlations (available directly from the Army Research Institute). (5) The Detection Ranges of Features of Armored Vehicles, ARI TR-78-A37, investigated the actual ranges at which specific identification of target vehicles can be made.

This research and literature review investigated the relationship between acoustic signatures of small-arms projectiles and the suppressive behavior which results from soldiers' perceptions of danger. Kinetic energy, which is associated with perceived loudness of passing projectiles, appears to be the primary physical property of projectiles that affects behavior under fire. The report is written for military personnel.

The objectives of the research were (a) to determine how air-to- ground and ground-to-air target handoff (target designation) has been accomplished in the past; and (b) to develop techniques for low-cost experimental studies of target handoff in order to develop new procedures and specify requirements for new equipment. An attempt was made to develop a battery of paper-and-pencil tests for selection or classification of individuals who will perform target handoff as part of their job. This effort did not produce a practically useful result. Analysis of recordings obtained of the verbal interchange between individuals performing simulated handoffs may provide useful cues as to the characteristics of effective verbal behavior during handoff. The simulator developed for the research appears useful as an inexpensive training device.

This report presents an investigation of problems of discomfort and fatigue resulting from extended use of the AN/PVS-5 Night Vision Goggles. The studies specifically explored the nature of the problems encountered with the goggles, the types of abilities degraded after lengthy goggle use, and the promise of solutions to the problems which were suggested by goggle users. (Author)

The present report presents the results of a literature survey designed to provide information on the psychological and associated physiological factors that might be expected to affect tank crew performance while operating buttoned up. The report also lists recommended design changes to be considered or incorporated into our present tanks so that buttoned-up or continuous operations can be sustained. The findings provide a background against which armor doctrine and training concerning buttoned-up operations can be formulated.