Chicken embryos were x-irradiated in ovo with 5-30 cGy (=priming dose) at the 13th-15th day of development. After 3-48 h, brain- and liver-cell suspensions were x-irradiated in vitro with (challenge) doses of 4-32 Gy. Significantly less radiation damage was observed when the radiation response was measured by scheduled DNA synthesis, nucleoid sedimentation and viscosity of alkaline cell lysates 12-36 h after the priming exposure. In vivo, pre-irradiation with 10 cGy enhanced regeneration as evidenced by the DNA content of chicken embryo brain and liver 24 h following a challenge dose of 4 Gy. From nucleoid sedimentation analyses in brain and liver cells immediately after irradiation with 16 Gy and after a 30-min repair period in the presence of aphidicolin, dideoxythymidine and 3-aminobenzamide or in the absence of these DNA repair inhibitors, it is concluded that a reduction of the initial radiation damage is the dominant mechanism of the ...
Briefly, 48 MOS microparticle sensors (essentially the same as those flown on .... at the Naval Research Lab to interpret the polarization of the incoming radio .... Adapter Satellite, to be published in Journal of Spacecraft and Rockets, 1994. ...
Plant roots exhibit remarkable developmental plasticity in response to local soil conditions. It is shown here that mild salt stress stimulates a stress-induced morphogenic response (SIMR) in Arabidopsis...Full Text Available
Osteoblasts are the primary cells responsible for bone formation. They also support osteoclast formation from bone marrow precursors in response to osteotropic factors by inducing receptor activator...Full Text Available
BackgroundIsoproterenol-induced cardiac hypertrophy in mice has been used in a number of studies to model human cardiac disease. In this study, we compared the transcriptional response...Full Text Available
Cytokines produced by Th2 cells are responsible for the pathogenesis of asthma. Th1-biased immune responses caused by attenuated salmonella have the potential to relieve asthmatic symptoms. We evaluated...Full Text Available
Background and ObjectivesDisruption of the vocal fold extracellular matrix (ECM) can induce a profound and refractory dysphonia. Pulsed dye laser (PDL) irradiation...Full Text Available
The goal of this study was to determine if the exaggerated morphine-induced conditioned place preference (CPP) response seen in adult rats after preweanling methylphenidate exposure is unique...Full Text Available
1. The effect of three single doses of nifedipine on exercise-induced asthma has been examined in 11 asthmatic subjects. 2. On four separate days patients undertook 6 min of exercise on a treadmill...Full Text Available
Recent studies suggest that calcium influx via L-type calcium channels is necessary for psychostimulant-induced behavioral sensitization. In addition, chronic amphetamine upregulates subtype...Full Text Available
Ozone (O3) is an oxidant gas that can directly induce lung injury. Knowledge of the initial molecular events of the acute O3response would be useful in developing biomarkers of...Full Text Available
Stem-boring insects and methyl jasmonate (MeJA) are thought to induce similar complex chemical and anatomical defenses in conifers. To compare insect- and MeJA-induced terpenoid responses, we analyzed...Full Text Available
Populus yunnanensis was employed as a model species to detect sexual differences in growth, physiological, biochemical, and ultrastructural responses to cadmium (Cd) stress, nitrogen...Full Text Available
In this report we define the parameters of the human immune response after immunization with hepatitis B vaccine. 2 wk after booster immunization, there is significant spontaneous secretion of antibody...Full Text Available
ObjectiveTo analyze the effect of CO2 pneumoperitoneum on the inflammatory responseinduced by sepsis during laparoscopy.Summary Background DataA...Full Text Available
In response to stress, cells start transcriptional and transcription-independent programs that can lead to adaptation or death. Here, we show that multiple inducers of autophagy, including nutrient...Full Text Available
The need for agents designed to modify immune response in the treatment of patients with viral infection, immunodeficiency, or cancer prompted the present study on the mechanisms of action of isoprinosine,...Full Text Available
Abstract Elevated temperatures resulting from climate change pose a clear threat to reef-building corals; however, the traits that might influence corals- survival and dispersal during climate change remain poorly understood. Global gene expression profiling is a powerful hypothesis-forming tool that can help elucidate these traits. Here, we applied a novel RNA-Seq protocol to study molecular responses to heat and settlement inducers in aposymbiotic larvae of the reef-building coral Acropora millepora. This analysis of a single full-sibling family revealed contrasting responses between short- (4-h) and long-term (5-day) exposures to elevated temperatures. Heat shock proteins were up-regulated only in the short-term treatment, while the long-term treatment induced the down-regulation of rib...
The chemopreventive efficacy of turmeric has been established in experimental systems. However, its mechanism(s) of action are not fully elucidated in vivo. The present study investigates the mechanism of turmeric-mediated chemoprevention in 7,12-dimethylbenz(a)anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis at 2, 4, 6, 10 and 12?weeks. Dietary turmeric (1%) led to decrease in DMBA-induced tumor burden and multiplicity, and enhanced the latency period in parallel, to its modulatory effects on oncogene products and various cellular responses during HBP tumorigenesis. DMBA-induced expression of ras oncogene product, p21 and downstream target, the mitogen-activated protein kinases were significantly decreased by turmeric during HBP carcinogenesis. Turmeric also diminished ...
FRAXA is one of a number of fragile sites in human chromosomes that are induced by agents like fluorodeoxyuridine (FdU) that affect intracellular thymidylate levels. FRAXA coincides with a >200...Full Text Available
Damaging inflammation arising from autoimmune pathology and septic responses results in severe cases of disease. In both instances, anti-inflammatory compounds are used to limit the excessive...Full Text Available
To capitalize on the response of tumor cells to ionizing radiation, we developed a controlled-release nanoparticle drug delivery system using a targeting peptide that recognizes a radiation-induced...Full Text Available
Gas exchange between the plant and the environment is severely hampered when plants are submerged, leading to oxygen and energy deficits. A straightforward way to reduce these shortages of oxygen and...Full Text Available
PurposeTo investigate the different components of full-field flash electroretinogram (ERG) responses in adult albino and pigmented rats at various time intervals following optic...Full Text Available
Recognition of HIV-1 ssRNA by TLR7 induces the production of the pro-inflammatory cytokines that may contribute to the systemic immune activation associated with HIV-1 disease progression. Here...Full Text Available
BackgroundThe expression of human virus surface proteins, as well as other mammalian glycoproteins, is much more efficient in cells of higher eukaryotes rather than yeasts. The limitations...Full Text Available
Macrophage activation by the proinflammatory cytokine interferon-γ (IFN-γ) is a critical component of the host innate response to bacterial pathogenesis. However, the precise nature...Full Text Available
Silver-haired bat rabies virus (SHBRV) infection induces a strong virus-specific immune response in the periphery of the host, but death is common due to the failure to open the blood-brain barrier...Full Text Available
Unless relaxation of the stringent response is achieved, all nongrowing bacteria rapidly develop resistance to autolysis induced by a variety of agents, including all classes of cell wall synthesis...Full Text Available
BackgroundThe immunoregulatory enzyme indoleamine 2,3-dioxygenase, which catalyzes the conversion of tryptophan into kynurenine, is expressed in a significant subset of patients...Full Text Available
Life history theory proposes that early-life cues induce highly integrated responses in traits associated with energy partitioning, maturation, reproduction, and aging such that the individual phenotype...Full Text Available
Ethnopharmacological relevanceHLXL is a traditional Chinese medicine that has long been used in folk medicine for the treatment of chronic inflammatory diseases....Full Text Available
1. Sensory fibres innervate the adrenal medulla but their function is not known. In this paper we have studied the effect of capsaicin-sensitive sensory fibres on the adrenal catecholamine (CA) response...Full Text Available
Retinoic acid inducible gene I (RIG-I) is a pattern recognition receptor (PRR) responsible for detection of nucleic acids from pathogens in the cytoplasm of infected cells and induction of type I interferon...Full Text Available
In rats, damage to neuronal populations in some brain regions occurs in response to neonatal alcohol exposure coinciding with the period of rapid brain growth. These alcohol-induced defects...Full Text Available
Human gingival fibroblasts were challenged with Treponema pectinovorum and Treponema denticola to test three specific hypotheses: (i) these treponemes induce different...Full Text Available
BackgroundIn animal groups such as herds, schools, and flocks, a certain distance is maintained between adjacent individuals, allowing them to move as a cohesive unit. Proximate...Full Text Available
In the cellular immune response, recognition by CTL-TCRs of viral antigens presented as peptides by HLA class I molecules, triggers destruction of the virally infected cell (Townsend, A.R.M., J. Rothbard,...Full Text Available
Mechanical forces can regulate various functions in living cells. The cytoskeleton is a crucial element for the transduction of forces in cell-internal signals and subsequent biological responses. Accordingly,...Full Text Available
Normal urinary bladder function requires contraction and relaxation of the detrusor smooth muscle (DSM). The DSM undergoes compensatory hypertrophy in response to partial bladder outlet obstruction...Full Text Available
Gamma interferon (IFN-γ) and the cellular responsesinduced by it are essential for controlling mycobacterial infections. Most patients bearing an IFN-γ receptor ligand-binding chain...Full Text Available
Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.
Adenovirus vaccine vectors derived from rare human serotypes have been shown to be less potent than serotype 5 (Ad5) at inducing immune responses to encoded antigens. To identify highly immunogenic...Full Text Available
Biased above threshold (VT), pulsed photocurrent (u) measurements on windowed silicon Pd gate MOS capacitors are shifted (DV) negatively by H2/N2, whereas Au gates shift positively under NO2/air. Below VT, the shifts are reversed by adjustments of interface state population. Minor temperature increases may coax the device from inversion to depletion, inducing sign reversal of the chemical response.
We studied the effect of booster injections and the long-term immune response after injections of an anti-human immunodeficiency virus type 1 (HIV-1) lipopeptide vaccine. This vaccine was injected alone...Full Text Available
Dendritic cells (DC) are the most potent antigen-presenting cells and play a central role in the induction of antiviral immune responses. Recently, we have shown that monocyte-derived DC (MoDC) from...Full Text Available
The purpose of a FAAT analysis is to estimate the probability of system upset to an electromagnetic threat, for systems on which we have incomplete information. As an example of this process, we will discuss the response of part of a telephone repeater system to wideband transients. We first estimate the currents induced on above-ground and buried cables. After that, we describe the simple circuit we used to build a model of the amplifier and protective devices. Finally, we describe the scaling of the energy deposited in the electronics, including its nonlinear large-signal response, with the amplitude of the wideband waveforms.
To determine a rat strain appropriate for carcinogenicity testing of FYX-051, a xanthine oxidoreductase inhibitor, we performed a 4-week oral toxicity study by administering 0.3, 1 and 3?mg/kg, and 1, 3 and 10?mg/kg of FYX-051 to male Sprague-Dawley (SD) and Fischer (F344) rats, respectively. Histopathology revealed that the degree of FYX-051-induced nephropathy was 3-fold stronger in SD rats than in F344 rats. Our previous study demonstrated that the key factor of species differences in FYX-051-induced nephropathy is purine metabolism. This observation led us to examine the involvement of purine metabolism in differences among two strains of rats. However, purine metabolism was proven not to be implicated as an important factor. Subsequently, other factors responsible for the strain diffe...
Pneumonia caused by Mannheimia haemolytica is an important disease of domestic sheep (DS, Ovis aries) and cattle (BO). M. haemolytica is a normal commensal of the upper respiratory tract in ruminants, but during stress and viral infection it breaches the host innate mucosal defense and descents into lungs causing fibrinous pleuropneumonia. Leukotoxin (Lkt) produced by M. haemolytica is cytolytic to all subsets of ruminant leukocytes. Earlier, we and others have shown that DS and BO LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) can mediate Lkt-induced cytolysis. It is not clear whether CR4 (CD11c/CD18), which is involved in chemotaxis, phagocytosis and regulates host immune response can also mediate Lkt-induced cytolysis in ruminants. The host innate immune response to M. haemolytica is poorly ...
Sulfur mustard (HD) is an alkylating and cytotoxic chemical warfare agent, which inflicts severe skin toxicity and an inflammatory response. Effective medical countermeasures against HD-caused skin toxicity are lacking due to limited knowledge of related mechanisms, which is mainly attributed to the requirement of more applicable and efficient animal skin toxicity models. Using a less toxic analog of HD, chloroethyl ethyl sulfide (CEES), we identified quantifiable inflammatory biomarkers of CEES-induced skin injury in dose- (0.05-2 mg) and time- (3-168 h) response experiments, and developed a CEES-induced skin toxicity SKH-1 hairless mouse model. Topical CEES treatment at high doses caused a significant dose-dependent increase in skin bi-fold thickness indicating edema. Histopathological e...
With an ageing population the demand for cheap, efficient implants is ever increasing. Laser surface treatment offers a unique means of varying biomimetic properties to determine generic parameters to predict cell responses. This paper details how a KrF excimer laser can be employed for both laser-induced patterning and whole area irradiative processing to modulate the wettability characteristics and osteoblast cell response following 24h and 4 day incubation. Through white light interferometry (WLI) it was found that the surface roughness had considerably increased by up to 1.5mm for the laser-induced patterned samples and remained somewhat constant at around 0.1mm for the whole area irradiative processed samples. A sessile drop device determined that the wettability characteristics diffe...
As an integral part of the Fast Test Reactor Vibration Program for Reactor Internals, the flow-induced vibrational characteristics of scaled Fast Test Reactor core internal and peripheral components were assessed under scaled and simulated prototype flow conditions in the Hydraulic Core Mockup. The Hydraulic Core Mockup, a 0.285 geometric scale model, was designed to model the vibrational and hydraulic characteristics of the Fast Test Reactor. Model component vibrational characteristics were measured and determined over a range of 36 percent to 111 percent of the scaled prototype design flow. Selected model and prototype components were shaker tested to establish modal characteristics. The dynamic response of the Hydraulic Core Mockup components exhibited no anomalous flow-rate dependent or modal characteristics, and prototype response predictions were adjudged acceptable.
A brain weight deficit of about 70 mg was induced at doses of approximately 75-mGy and a deficit of 60 mg was induced at 100 mGy. This confirms the effects projected and observed by Wanner and Edwards. Although the data do not demonstrate a clear dose-response relationship between the 75-mGy and 100-mGy groups, the data are statistically consistent with a dose-response effect because of the overlapping confidence intervals. The lack of a statistically significant observation is most likely related to the small difference in doses and the limited numbers of animals examined. There are several factors that can influence the brain weight of guinea pig pups, such as caging and housing conditions, the sex of the animal, and litter size. These should be taken into account for accurate analysis. Dam weight did not appear to have a significant effect. The confirmation of a micrencephalic effect ...
Full text: An adaptive response is a decreased biological effect induced by a priming radiation dose given prior to a challenge dose. Adaptive responses contradict the linear-nothreshold model of risk estimation. The pKZ1 mouse chromosomal inversion assay is an extremely sensitive assay for studying the mutagenic effect of low dose radiation. A non-linear dose response for chromosomal inversion has been observed in pKZ1 spleen and prostate after a single whole body irradiation with doses between 1?Gy and 10mGy. Doses between 5-10?Gy resulted in an induction in inversions and doses between 1-10mGy resulted in a reduction below endogenous inversion frequency. These results suggest that doses in the 1-10 mGy range cause host responses which overcompensate by not only preventing inversions that would normally occur as a result of the low doses of radiation but also by preventing some of ...
We hypothesize that the mushroom-derived active compound may be a potential strategy for increasing survival in response to influenza virus (H1N1) infection through the stimulation of host innate immune response. The validity of the hypothesis can be tested by immune response to influenza infection as seen through survival percentage, virus clearance, weight loss, natural killer cell cytotoxicity, Tumor Necrosis Factor-? (TNF-?) and Interferon-gamma (IFN-?) levels, lytic efficiency in the spleens of mice and inducible nitric oxide synthase mRNA expressions in RAW 264.7 murine macrophage cells. The hypothesis may improve people's quality of life, reduce the medical cost of our healthcare system and eliminate people's fears of influenza outbreak. PMID:21660092
We evaluated the similarities between ozone-induced and mite-induced emission of volatile organic compounds (VOCs) from lima beans, and tested the response of the natural enemies of herbivores to these emissions using trophic system of two-spotted spider mites and predatory mites. The acute ozone-exposure and spider mite-infestation induced the emission of two homoterpenes, (E)-4,8-dimethyl-1,3,7-nonatriene and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, and (Z)-3-hexenyl acetate. Only plants with spider mite-infestation emitted the monoterpene (E)-{beta}-ocimene. Predatory mites were equally attracted to ozone-exposed and unexposed plants, but discriminated between spider mite-infested and uninfested plants, when both were exposed to ozone. The similarities between ozone and herbivore-induced VOCs suggest that plant defence against phytotoxic ozone and the production of VOCs ...
Efflux of dopamine through the dopamine transporter (DAT) is critical for the psychostimulatory properties of amphetamines, but the underlying mechanism is unclear. Here we show that Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) plays a key role in this efflux. CaMKIIalpha bound to the distal C terminus of DAT and colocalized with DAT in dopaminergic neurons. CaMKIIalpha stimulated dopamine efflux via DAT in response to amphetamine in heterologous cells and in dopaminergic neurons. CaMKIIalpha phosphorylated serines in the distal N terminus of DAT in vitro, and mutation of these serines eliminated the stimulatory effects of CaMKIIalpha. A mutation of the DAT C terminus impairing CaMKIIalpha binding also impaired amphetamine-induced dopamine efflux. An in vivo role for CaMKII was supported by chronoamperometry measurements showing reduced amphetamine-induced dopamine efflux in response to the ...
Fast Test Reactor core internal and peripheral components were assessed for flow-induced vibrational characteristics under scaled and simulated prototype flow conditions in the Hydraulic Core Mockup as an integral part of the Fast Test Reactor Vibration Program. The Hydraulic Core Mockup was an 0.285 geometric scale model of the Fast Test Reactor internals designed to simulate prototype vibrational and hydraulic characteristics. Using water to simulate sodium coolant, vibrational characteristics were measured and determined for selected model components over the scaled flow range of 36 to 110%. Additionally, in-situ shaker tests were conducted on selected Hydraulic Core Mockup outlet plenum components to establish modal characteristics. Most components exhibited resonant response at all test flow rates; however, the measured dynamic response was neither abnormal nor anomalously flow-rate dependent, and the predicted ...
AbstractBackground: The dinitrofluorobenzene/dinitrosulfonic acid (DNFB/DNS) model was originally described as an experimental model of intestinal inflammation resembling human ulcerative colitis (UC). Due to the absence of acceptable UC experimental models for pharmacological preclinical assays, here we examine the immune responseinduced in this model. Methods: Balb/c mice were sensitized by skin application of DNFB on day 1, followed by an intrarectal challenge with DNS on day 5. We further expanded this model by administering a second DNS challenge on day 15. The features of colonic inflammation and immune response were evaluated. Results: The changes observed in colonic tissue corresponded, in comparison to the trinitrobenzene sulfonic acid (TNBS) colitis model, to a mild mucosal effe...
Redd1, a recently discovered stress-response gene, is regulated by hypoxia via hypoxia-inducible factor 1 (HIF-1) and by DNA damage via p53/p63; however, the signaling pathway by which its expression is induced by hypoxia has not been elucidated. We demonstrated that the up-regulation of Redd1 transcription by hypoxia and high cell density (HCD) depends on cooperation between Sp1 and HIF-1#alpha# downstream of the PI3K/Akt pathway.
The autoradiographic appearance of the gastric mucosa, 5 hours after administration of indomethacin, was investigated in 29 adult rats. Indomethacin induced superficial gastric erosions. Autoradiography demonstrated the presence of viable gastric cells (as deduced by their ability to incorporate 3H-cytidin, an RNA precursor) not only in the mucosa without erosions, but also in the mucosa underneath the superficial erosions. The results indicate that indomethacin induced gastric erosions are not the superficial expression of a necrotic process taking place in the full thickness of the gastric mucosa at a particular site. A lumen-borne mechanism appears to be responsible for the formation of erosive areas in the mucosa.
Biomonitoring requires the application of batteries of different biomarkers, as environmental contaminants induce multiple responses in organisms that are not necessarily correlated. Omic technologies were proposed as an alternative to conventional biomarkers since these techniques quantitatively monitor many biological molecules in a high-throughput manner and thus provide a general appraisal of biological responses altered by exposure to contaminants. As the studies using omic technologies increase, it is becoming clear that any single omic approach may not be sufficient to characterize the complexity of ecosystems. This work aims to provide a preliminary working scheme for the use of combined transcriptomic and proteomic methodologies in environmental biomonitoring. There are difficulti...
Methods and apparatus for detecting the presence of explosives by analyzing a vapor sample from the suspect vicinity utilize at least one microcantilever. Explosive gas molecules which have been adsorbed onto the microcantilever are subsequently heated to cause combustion. Heat, along with momentum transfer from combustion, causes bending and a transient resonance response of the microcantilever which may be detected by a laser diode which is focused on the microcantilever and a photodetector which detects deflection of the reflected laser beam caused by heat-induced deflection and resonance response of the microcantilever. 2 figs.
Ramsar, a city in the northern Iran, has the highest level of natural background radiation in the world. It has been clearly shown that low doses of ionising radiation can induce resistance to subsequent higher exposures. This phenomenon is termed radioadaptive response. We have compared induction of cytogenetic radioadaptive response by High Natural Background Radiation (HNBR) in Ramsar and X-ray occupational exposure as conditioning doses in human peripheral blood lymphocytes. 30 healthy control individuals, living in Ramsar but in normal background radiation areas, 15 healthy individuals from Talesh Mahalleh, a region with extraordinary high level of background radiation, and 7 X-ray radiographers working in Ramsar hospital located in normal natural background ionising radiation area were evaluated. Peripheral blood samples were prepared and exposed to challenge dose of 0 and 2 Gy. Lymphocytes were scored using analysis ...
Carbon steel is frequently used to construct concentrated sulphuric acid storage tanks. This paper discussed the corrosion performance of carbon steel tanks and outlined the underlying mechanisms responsible for major corrosion modes. Analyses of hydrogen grooving and dilute acid corrosion failure mechanisms were presented. Recent corrosion-induced leak failures were also discussed. The use of anodic protection and organic coatings as a corrosion control measure was also evaluated. The results of laboratory studies that were conducted to understand corrosion-induced failures showed that carbon steel electrodes exhibited transpassive corrosion at relatively high anodic potentials, while stainless steel electrodes exhibited transpassive corrosion at anodic potentials less than 1 V. It was concluded that corrosion-induced leaks can be prevented by using anodic protection and baked phenolic coating ...
Objective To evaluate the inhibitory property of de-glycyrrhizinated extract of Glycyrrhiza glabra root and its phytoconstituents (glabridin, isoliquiritigenin and glycyrrhizin) on LPS-induced production of pro-inflammatory mediators. Materials and methods Inhibitory effect of G. glabra extract and its phytoconstituents were studied on lipopolysaccharide (LPS)-induced nitric oxide (NO), interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) levels in J774A.1 murine macrophages. Results G. glabra and isoliquiritigenin significantly inhibited LPS stimulated NO, IL-1 beta and IL-6 production. Glabridin showed significant inhibition of NO and IL-1 beta release, but failed to attenuate IL-6 levels at the tested concentrations. In addition, glycyrrhizin did not exhibit inhibitory response towar...
Exposure to urban air pollution is an independent risk factor for increased cardiovascular diseases. Heat shock protein 70 (HSP70) has been implicated in the pathogenesis of vascular dysfunction and cardiovascular diseases. This study has been designed to determine whether inhalation of urban air induces HSP70 expression in the lung and blood as well as the association of HSP70 and air pollution-induced vascular dysfunction. Apolipoprotein E (Apo-E) deficient mice were exposed to diesel exhaust (DE) either acutely (3 days, 200 or 400 g/m3 for 6 h/day) or chronically (7 weeks, 200 or 400 g/m3 for 6 h/day). HSP70 was measured in the lung using immunohistochemistry, and in the plasma by ELISA. Abdominal aorta rings were used to determine vascular functional responses. Chronic DE-exposure incr...
1-Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) is an anti-inflammatory agent with a propenone moiety and chemically synthesized recently. In this study, we examined the chemopreventive effect of FPP-3 on 7,12-dimethylbenz[a]anthracene (DMBA)-induced genotoxicity in MCF-7 cells. FPP-3 reduced the formation of the DMBA-DNA adduct. DMBA-induced CYP1A1 and CYP1B1 gene expression and enzyme activity were inhibited by FPP-3. It inhibited DMBA-induced aryl hydrocarbon receptor (AhR) transactivation and DMBA-inducible nuclear localization of the AhR. Induction of detoxifying phase II genes by chemopreventive agents represents a coordinated protective response against oxidative stress and neoplastic effects of carcinogens. Transcription factor NF-E2 related factor 2 (Nrf2) regulates antioxidant response element (ARE) of phase II detoxifying and antioxidant enzymes, such ...
Alzheimer's disease (AD) is a progressive neurodegenerative disorder of the elderly accounting for the vast majority of dementia. Recently, many studies have implicated the role of inflammatory response, especially neuroinflammatory response in the development and progression of AD. However, the underlying mechanism of how inflammatory responseinduces AD is unknown. Kynurenine pathway is a major route of the amino acid tryptophan catabolism, resulting in the production of nicotine adenine dinucleotide and other neuroactive intermediates: quinolinic acid (QA) and kynurenic acid (KA). QA exerts different toxic effects, including over-activation of N-methyl-d-aspartate (NMDA) receptor and excitotoxicity, synaptic dysfunction and neuronal death. On the other hand, KA is identified as the only...
The aim of this study was to measure the nociceptive response (avoidance latency) of the land snail Megalobulimus abbreviatus (N=8 in each group) after topical capsaicin exposure (0.1% and 0.5% in 20% ethanol) and to compare it to a well-studied stressful (50??C) thermal stimulus model. We also tested if ruthenium red, and capsazepine, respectively nonselective and selective TRPV1 receptor antagonists, could modify both capsaicin- and thermal-evoked responses. Finally, animals were pretreated with morphine, naloxone or morphine plus naloxone prior to capsaicin stimuli. Latencies were measured when the animal lifted its head?foot complex 1?cm from the substrate. Data were compared using ANOVA and LSD post hoc, and the Student T Test (pM. abbreviatus.
A theoretical framework for the hierarchical multiscale modeling of inelastic response of heterogeneous materials has been presented. Within this multiscale framework, the second gradient is used as a non local kinematic link between the response of a material point at the coarse scale and the response of a neighborhood of material points at the fine scale. Kinematic consistency between these scales results in specific requirements for constraints on the fluctuation field. The wryness tensor serves as a second-order measure of strain. The nature of the second-order strain induces anti-symmetry in the first order stress at the coarse scale. The multiscale ISV constitutive theory is couched in the coarse scale intermediate configuration, from which an important new concept in scale transitions emerges, namely scale invariance of dissipation. Finally, a strategy for developing meaningful kinematic ISVs and ...
The spectral energy-dependence of the radiation-induced ESR signal has been studied in ovine cortical bone. Crushed bone samples were irradiated using photon beams with effective energies in the range from 0.06 to 6 MeV, and electron beams with mean energies in the range from 2 to 10 MeV. The photon and electron data were normalized to a dose to bone of 50 Gy and the results are reported as response relative to the ESR signal for photon irradiation at 1.25 MeV ("6"0Co). The photon irradiation results show that the ESR response is greatest at low energies with a relative value of 1.2 at 0.06 MeV. The relative response decreases, as the energy increases, to approximately 0.85 in the region of 2 to 3 MeV. These variations in the relative ESR responses are significantly less than the ESR energy-dependent responses reported in the literature for human tooth enamel ...
Pregnant rats in 11d and 16d of their pregnancy were given one-off whole body exposure by "1"3"7Cs #gamma# rays to 0.2, 0.4, 0.9 and 2.0 Gy, respectively. Changes were observed in conditioned drinking response and cerebrum hippocampi cone cell number of the baby rats exposed to the #gamma# rays in different periods of their embryo development. As a result, that pregnant rats exposed to "1"3"7Cs #gamma# rays in different pregnant periods may induce significant decrease in cerebrum hippocampi cone cell number and achieving rate of conditioned drinking response of the babies. The dose-response relationship can be described by Y=a-b log_1_0D. The achieving rate of conditioned drinking response were significantly correlated to cerebrum hippocampi cone cell number in the babies, and the achieving rate of conditioned drinking response of the babies exposed at pregnant ...
BackgroundHIV infection causes a qualitative and quantitative loss of CD4+ T cell immunity. The institution of anti-retroviral therapy (ART) restores CD4+ T...Full Text Available
Tomato (Lycopersicon esculentum var. Better Boy) plants were transformed with a tomato leaf wound-inducible polygalacturonase (PG) β-subunit gene in the antisense orientation...Full Text Available
The properties of a nonviable, aqueous ether-extracted Brucela abortus preparation, Bru-Pel, are described. In addition to inducing a "virus-type" interferon response and protecting mice against challenge with otherwise lethal doses of Semliki Forest virus, Bru-Pel is demonstrated to have potent antitumor properties in mice. These antitumor effects appear to be mediated by an increase in nonspecific resistance similar to that seen with other experimental antitumor agents. PMID:728911
BackgroundHerpes simplex virus type-1 (HSV-1) infections can cause a number of diseases ranging from simple cold sores to dangerous keratitis and lethal encephalitis. The interaction...Full Text Available
The leukocyte-enriched p110γ and p110δ isoforms of PI3K have been shown to control in vitro degranulation of mast cells induced by cross-linking...Full Text Available
The relationships of hydrogen alloyed #beta#-titanium alloy deformation behaviour to its microstructure and texture are investigated. It is shown that plasticity increases and strain induced texture changes at low hydrogen contents (0.1-0.2 mass %). Possible mechanisms responsible for specific features of #beta#-Ti alloy deformation are discussed. The study is made using alloy VT35 doped with hydrogen
Tow experiments were carried out in 1981 and 1982 growth seasons at the greenhouse of the department of agriculture for soils and water researches, atomic energy authority, at inshas, to investigate the responses of two mutation derived lines of sesame and the local cultivar giza 25 to the application of micro nutrients. The possible effect of radiation on germination and growth of sesame seed was also studied in a separate experiment conducted in 1985 season, at inshas.
If the soft supersymmetry (SUSY) breaking masses and couplings are complex and cancellations do take place in the SUSY induced contributions to the fermionic electric dipole moments, then the CP- violating soft phases can drastically modify much of the known phenomenological pattern of the minimal supersymmetric standard model. In particular, the squark loop content of the dominant Higgs production mechanism at the large hadron collider, the gluon-gluon fusion mode, could be responsible for large corrections to the known cross sections. (15 refs).
Spontaneous and ultraviolet-induced changeabilities of wine yeasts from the killer state to sensitive one have been studied. Observed often spontaneous changes of killer and neutral phenotypes under laboratory store conditions as well as high mutation frequency of genetic elements responsible for the killer indication on ultraviolet irradiation testify that often encounterability in nature and in the production of sensitive yeasts is attributed to high frequency of mutation changes of the killer and neutral phenotypes to the sensitive state.
The objective of this study was to determine if genistein (GEN) modulation of the immune responses might contribute to the increased host resistances to tumors. A time-course study was performed...Full Text Available
An experimental campaign, aiming to investigate the perturbation effects induced by fixed obstacles on turbulence measurements in airflows at the air-sea interface, was carried out at the marine platform of the Italian Navy, located in the harbour of La Spezia (North Ligurian Sea, Italy) on 28., 29., and 30. June 1994. This study was prompted by the ever-growing interest in more reliable estimates of energy, mass, and momentum exchanges between water surfaces and atmosphere, whose measurements are severely limited by the geometrical constraints of floating or fixed platforms where they are installed. Two types of meteorological instruments have been used: fast response (20 and 21 Hz) ultrasonic anemometers and fluxmeters to measure turbulent momentum, sensible, and latent heat fluxes and slow-response sensors (less than 4 Hz and sampled at a rate of 10{sup 2} Hz) to measure average wind and temperature vertical profiles in ...
Background & AimsMolecular mechanisms underlying alcoholic liver disease (ALD) are still not fully understood. Activating transcription factor-4 (ATF4) is the master coordinator of the integrated stress response (ISR), an adaptive pathway triggered by multiple stressors. which can promote cell death and induce metabolic dysregulation if the stress is intense or prolonged. The aim of this study was to assess the effect of alcohol on the ISR signaling pathway in human liver cells and to define the role of cytochrome P450 2E1 (CYP2E1) in this response. MethodsPrimary cultured human hepatocytes and human HepG2 cells over-expressing CYP2E1 by adenoviral infection were exposed to ethanol (25-100mM) for 8-48h. ResultsEthanol treatment of both liver cells up-regulated ATF4 as well as the pro-survi...
Active oxygens produced by low-dose irradiation can induce the synthesis of proteins involved in the active oxygen reduction path and can activate the chemical self-defense mechanisms in vivo, which can alleviate the injuries caused by active oxygens themselves. The following findings suggests that it is not only by low-dose irradiation that can induce the responses described above but also by any physical and/or chemical stresses which can produce small amount of active oxygens in vivo. 1. X-irradiation with 0.5 Gy and/or water immersion and restraint induced heat shock protein (HSP)70 in rat stomach cells. HSP70 was also induced in adrenal cells by paraquat administration. 2. The SOD activity in pancreas of rat significantly increased by #gamma#-irradiation with 0.5 Gy. 0.5 Gy irradiation preceeding the alloxan administration significantly suppressed the increase in pancreatic ...
Two plasmids which express either nearly intact or truncated filamentous hemagglutinin (FHA) from Bordetella pertussis and which are marked with a tetracycline resistance (Tcr) gene were transformed into Salmonella dublin SL1438, an aroA deletion mutant intended for use as an attenuated oral vaccine against salmonellosis. These S. dublin recombinants, when fed to mice, induced serum immunoglobulin, immunoglobulin M (IgM), and sometimes IgA antibody responses to FHA and S. dublin. In addition, IgA antibodies against FHA were found in gut wash fluids. S. dublin carrying pDB2300, a multicopy plasmid encoding truncated FHA protein, induced a better antibody response than did S. dublin carrying pDB2000, a low-copy-number plasmid encoding full-sized FHA. Administration of tetracycline to mice enhanced the stability of recombinant plasmids, and tetracycline-treated mice developed higher anti-FHA titers. ...
Purpose To study the activation and expression of vascular (aorta and small mesenteric arteries) potassium channels during septic shock with or without modulation of the NO pathway. Methods Septic shock was induced in rats by peritonitis. Selective inhibitors of vascular KATP (PNU-37883A) or BKCa [iberiotoxin (IbTX)] channels were used to demonstrate their involvement in vascular hyporeactivity. Vascular response to phenylephrine was measured on aorta and small mesenteric arteries mounted on a wire myograph. Vascular expression of potassium channels was studied by PCR and Western blot, in the presence or absence of 1400W, an inducible NO synthase (iNOS) inhibitor. Aortic activation of the transcriptional factor nuclear factor-kappaB (NF-?B) was assessed by electrophoretic mobility shift as...
AbstractBackground: A defective innate immune response may contribute to the pathogenesis of Crohn's disease (CD) and ulcerative colitis (UC). Employing a global gene expression analysis, this study was aimed at identifying specifically regulated genes within the epithelial compartment in inflammatory bowel disease (IBD). Methods: The epithelial fraction of human ileal mucosa samples from surgical specimens was obtained by laser microdissection. Gene expression was examined by global expression profiling (n = 18, Affymetrix), quantitative reverse-transcription polymerase chain reaction (RT-PCR) (n = 35), immunoblot analysis (n = 9), and immunohistochemistry (n = 25). Results: Global expression profiling revealed a pronounced downregulation of the retinoic acid-inducible gene I (RIG-I) with...
Abstract Strains of Pseudomonas syringae are effective in controlling postharvest diseases of citrus fruits, and antagonistic activity has been correlated with in vitro production of lipodepsipeptides. Additionally, biocontrol agents can induce a range of defence mechanisms of resistance in citrus tissue that result in a broad spectrum of metabolic modifications, such as systemic acquired resistance, induced systemic resistance and production of reactive oxygen species. The aim of this study was to evaluate the expression of syringomycin (syrB1) and syringopeptin (sypA) synthetase genes from P.syringae pv. syringae biocontrol strains in vitro on different culture media and in vivo on citrus fruits (Citrus sinensis cv. Tarocco) during the interaction with Penicillium digitatum by quantitati...
Lung cancer is still difficult to treat by current chemotherapeutic procedures. We recently found that MVL, an anti-HIV lectin from blue-green algae Microcystis viridis, also has antitumor activity. The objective of this study was to investigate apoptosis-inducing activity of recombinant MVL (R-MVL) and proteomic changes in A549 cells, and to identify the molecular pathways responsible for the anti-cancer action of R-MVL. We found that R-MVL induces A549 cells apoptosis in a dose-dependent manner by using MTT assay, fluorescent microscope (FM) and flow cytometry (FCM), and the IC50 was calculated to be 24.12??g/ml. Subsequently, 7 altered proteins in R-MVL-treated A549 cells were identified, including upregulated aldehyde dehydrogenase 1 and ?-actin, and five downregulated proteins: heat s...
Glycyrrhizin is a triterpene glycoside, a major active constituent of licorice (Glycyrrhiza glabra) root and numerous pharmacological effects like anti-inflammatory, anti-viral, anti-tumour and hepatoprotective activities has been attributed to it. In this study we evaluated the anti-inflammatory activities of glycyrrhizin in mice model of acute inflammation, carrageenan-induced pleurisy. We report here that glycyrrhizin (given at 10mg/kg i.p. 5min prior to carrageenan) exerts potent anti-inflammatory effects in this model. Injection of carrageenan into the pleural cavity of mice elicited an acute inflammatory response characterized by fluid accumulation in the pleural cavity which contained a large number of neutrophils (PMNs) as well as an infiltration of PMNs in lung tissues and subsequ...
Several lines of evidence are presented that indicate that the level of tetracycline resistance of Esherichia coli strains harboring plasmid pBR322 varies according to whether the SOS system of the host bacteria has been induced. These include use of strains in which the SOS system is expressed constitutively (lexA def.), is thermoinducible (recA441) or noninducible (lexA ind-), or is highly repressed (multiple copies of lexA+). Similar induction was observed with the product of another plasmid gene, beta-lactamase. The amounts of extractable plasmid DNA were also increased by SOS induction, and we propose that the SOS-induced increases in levels of tetracycline resistance and beta-lactamase activity are due to an increased plasmid copy number.
An important aspect of ecosystem sustainability is the ability to withstand and recover from disturbance or stress. In this study, we investigated the effect of a heat-disturbance on soil microbial biomass, microbial activity in response to the addition of organic acid (malate), and microbial community structure in a laboratory experiment. The soils investigated were from a jarrah (Eucalyptus marginata) forest that had undergone rehabilitation following bauxite mining 12 years previously. Soils from a full factorial of two field treatments; contour ripping induced micro-topography (mound or furrow) and prior exposure to prescription fire (burnt or non-burnt), were sampled and found to exhibit treatment-dependent differences in soil biological and chemical properties. Exposure of soil micro...
Abstract Epstein-Barr virus (EBV), which infects not only B cells, but also T cells and natural killer (NK) cells, is associated with multiple lymphoid malignancies. Recently, the proteasome inhibitor bortezomib was reported to induce apoptosis of EBV-transformed B cells. We evaluated the killing effect of this proteasome inhibitor on EBV-associated T lymphoma cells and NK lymphoma cells. First, we found that bortezomib treatment decreased the viability of multiple T and NK cell lines. No significant difference was observed between EBV-positive and EBV-negative cell lines. The decreased viability in response to bortezomib treatment was abrogated by a pan-caspase inhibitor. The induction of apoptosis was confirmed by flow cytometric assessment of annexin V staining. Additionally, cleavage o...
In vulnerable individuals, exposure to stressors can result in chronic disorders such as generalized anxiety disorder (GAD), major depressive disorder (MDD), and post-traumatic stress disorder (PTSD). The extended amygdala is critically implicated in mediating acute and chronic stress responsivity and anxiety-like behaviors. The bed nucleus of the stria terminalis (BNST), a subregion of the extended amygdala, serves as a relay of corticolimbic information to the paraventricular nucleus of the hypothalamus (PVN) to directly influence the stress response. To investigate the influence of the corticosteroid milieu and housing conditions on BNST function, adult C57Bl/6J were either acutely or chronically administered corticosterone (CORT, 25mg/kg in sesame oil) or vehicle (sesame oil) or were g...
Nano photonic materials are synthetically manufactured crystals at the nano scale with the target of creating a microstructure with a special electro-magnetic periodicity. Such nano photonic materials have the ability to control light propagation and thus are capable of creating photonic bandgaps in the frequency domain. We propose using nano photonic crystals as sensors to detect microdamage in composite materials. We demonstrate using a simulation model that a nano photonic sensor attached to a composite bar experiences a significant change in its bandgap profile when damage is induced in the composite bar. The model predicts the frequency response of the nano photonic sensor using the transfer matrix method. A damage metric to evaluate the change in the frequency response is developed. Successful developments of nano photonic sensors allow damage identification at scales not attainable using current sensing technologies.
The class of Spirochetes comprises a wide array of clinically important pathogens, including Treponema pallidum causing syphilis as well as Borrelia burgdorferi, the agent of Lyme disease (LD). Diseases caused by spirochetes are characterized by specific sequelae of host reactions, and also by characteristic antibody response patterns. Over the last decades, research on the interaction of spirochetes with the hosts immune system had a strong emphasis on outer membrane lipoproteins. In fact, these structures have been convincingly shown to activate immune cells via CD14 and Toll-like receptor (TLR)-2, and recent data also indicate an interaction with lipopolysaccharide (LPS)-binding protein (LBP). In particular, the interaction of B. burgdorferi with TLR-2 could not only be demonstrated in ...
Mycoplasma ovipneumoniae is associated with chronic non-progressive pneumonia of sheep and goats. As with many other mycoplasmas involved in animal diseases, protective immune responses have not been achieved with vaccines, even though antibody responses can be obtained. This study focuses on characterizing the interaction of M. ovipneumoniae with ovine PBMC using carboxy-fluorescein-succinimidyl-ester (CFSE) loading and flow cytometry to measure lymphoid cell division. M. ovipneumoniae induced a strong in vitro polyclonal suppression of CD4^+, CD8^+, and B blood lymphocyte subsets. The suppressive activity could be destroyed by heating to 60^oC, and partially impaired by formalin and binary ethyleneimine treatment that abolished its viability. The activity resided on the surface-exposed m...
Acidification is one of the most common and serious problems inducing process failure in anaerobic digesters. The production of volatile fatty acids (VFAs) mainly triggers acidic shock. However, little is known about the bacteria involved in the processes of acidogenic metabolism, such as fermentation and reductive acetogenesis. Here, the metabolic responses of a methanogenic community to the acidification and resulting process deterioration were investigated using transcriptional profiling of both the 16S rRNA and formyltetrahydrofolate synthetase (FTHFS) genes. The 16S rRNA-based analyses demonstrated that the dynamic shift of bacterial populations was closely correlated with reactor performance, especially with VFA accumulation levels. The pH drop accompanied by an increase in VFAs stim...
Laser-induced phase-separation polymerization of a porous acrylate polymer is used for in-situ fabrication of dialysis membranes inside glass microchannels. A shaped 355 nm laser beam is used to produce a porous polymer membrane with a thickness of about 15 .mu.m, which bonds to the glass microchannel and forms a semi-permeable membrane. Differential permeation through a membrane formed with pentaerythritol triacrylate was observed and quantified by comparing the response of the membrane to fluorescein and fluorescently tagging 200 nm latex microspheres. Differential permeation was observed and quantified by comparing the response to rhodamine 560 and lactalbumin protein in a membrane formed with SPE-methylene bisacrylamide. The porous membranes illustrate the capability for the present technique to integrate sample cleanup into chip-based analysis systems.
Measurement of serum biochemical parameters in response to metal exposures can be especially useful to help identify target organs of toxicity as well as the general health status of animals. Oreochromis niloticus were exposed to 5.0?mg/L?Zn, 1.0?mg/L?Cd, and 5.0?mg/L?Zn?+?1.0?mg/L?Cd mixture for 7 and 28?days, and alterations in serum enzyme activities and ion levels were measured. Significant changes in all the biochemical parameters were found to be time dependent. Following metal exposure, alkaline phosphatase activity was elevated at both exposure periods. No changes in activities of lactate dehydrogenase and lipase were observed in response to single or combined Zn and Cd exposure at 7?days while they increased at 28?days. Fish exposed to metals showed a decrease in cholinesterase ac...
Natural sunlight induces a genotoxic response in cultured CHO cells pre-treated with shale oil retort process water. Near ultraviolet light (NUV) component of the solar spectrum is the apparent radiation responsible for photoactivation. Cultured human skin fibroblasts are acutely sensitive to the genotoxic effects of photoactivated process water. The mutagenic potential of photoactivated process water in human cells is the same as that witnessed for an equivalent killing dose of the potent skin carcinogen FUV. DNA repair processes are involved in modulating genotoxic effects of this photo-induced process. The exact magnitude of the potential health-related and environmental risks resulting from photoactivation of retort process waters and other oil shale by-products is unassessed at this time. Our demonstration that a significant rate of mutation occurs in cultured human cells exposed to high dilutions ...
Current projections of the response of the biosphere to global climatic change indicate as much as 50% to 90% spatial displacement of extratropical biomes. The mechanism of spatial shift could be dominated by either (1) competitive displacement of northern biomes by southern biomes, or (2) drought-induced dieback of areas susceptible to change. The current suite of global biosphere models cannot distinguish between these two processes, thus determining the need for a mechanistically based biome model. The model is in an early stage of development and will require several enhancements, including explicit simulation of potential evapotranspiration, extension to boreal and tropical biomes, a shift from steady-state to transient dynamics, and validation on other continents.
1. Chronic exposure of male Microtus pennsylvanicus to photoperiods with 8, 10 and 12 hr of light per day results in gonadal regression, molt to winter pelage and significant reductions in body weight and food consumption relative to voles kept on photoperiods with 13 and 14 hr of light per day. 2. A precise critical daylength is observed in this species as exposure to photoperiods with 12 or fewer hours of light per day results in complete gonadal involution, seasonal molt and loss of body weight. 3. Pinealectomy abolishes all short-photoperiod inducedresponses in this species. PMID:2573458
High temperature deformation behavior of an alpha + beta titanium alloy Ti-3Al-4V has been investigated at 910 deg. C. by using the method of cross head speed cycling. On the basis of flow stress, strain rate and strain rate sensitivity data, the alloy was found to exhibit strain hardening at this temperature which resulted in degradation in superplastic properties of the alloy. A high beta-phase volume fraction and grain-growth in both alpha and beta phases were considered responsible for the observed hardening effect. (author)
This paper described the application of an AC surface probe, similar to presently used eddy current probes, to the measurement of DC transport critical currents and critical state dissipation in high {Tc} superconductors. It has been shown that the probe can provide quantitative measurement of the full field penetration in superconducting samples by measuring the response of AC induced screening currents for superconducting materials in the form of tapes with overlayers of silver. In this manner, the AC probe can be used to replace the contact DC probe for determining critical currents in a noncontacting and local manner suitable for scanning over or along the sample.
This paper described the application of an AC surface probe, similar to presently used eddy current probes, to the measurement of DC transport critical currents and critical state dissipation in high T_c superconductors. It has been shown that the probe can provide quantitative measurement of the full field penetration in superconducting samples by measuring the response of AC induced screening currents for superconducting materials in the form of tapes with overlayers of silver. In this manner, the AC probe can be used to replace the contact DC probe for determining critical currents in a noncontacting and local manner suitable for scanning over or along the sample.
This paper described the application of an AC surface probe, similar to presently used eddy current probes, to the measurement of DC transport critical currents and critical state dissipation in high [Tc] superconductors. It has been shown that the probe can provide quantitative measurement of the full field penetration in superconducting samples by measuring the response of AC induced screening currents for superconducting materials in the form of tapes with overlayers of silver. In this manner, the AC probe can be used to replace the contact DC probe for determining critical currents in a noncontacting and local manner suitable for scanning over or along the sample.
A transient eddy current measurement method is presented to determine the thickness and conductivity of a conductive plate. The conductive plate is induced by an air-cored coil, the magnetic flux density along the axial is measured and the various signals corresponding to plates with different thickness and conductivity are calculated using a 3D transient eddy current simulator. Characteristic features are obtained from the transient response. A similarity-based modeling method is utilized in this study to estimate the thickness and conductivity of the conductive plate. (author)
Aerial lines or cables, as one mainly energy transport path of electronic system when illuminated by HEMP, has been often modeled by field-to-transmission line model. However, in many cases, authors too often encounter some confusing statements to the lines effects during experimental procedure. The aim of this paper is to present and discuss these cases, such as the electromagnetic environment above the ground plane, the contribution of the different electromagnetic field component to the induced current and voltage, variations of the load current for different line heights and ground conductivities etc. (authors)
The post (neutron) -irradiation high-temperature tensile and creep-rupture properties, deformation and fracture characteristics of austenitic alloys, particularly solution annealed Type 316 steel, are surveyed and correlated with the damage structures developed as a function of irradiation temperature (and dose). The mechanisms proposed to explain the irradiation-induced changes in properties and behaviour are summarised. The factors responsible for the observed differences in the post-irradiation and 'in-reactor' creep-rupture properties and behaviour of an austenitic steel are discussed in terms of the helium gas and stress driven growth of small intergranular bubbles and the atom plating associated with their growth and coalescence. (author).
Marketing-led enterprise change management initiated by a major UK contractor is explored in this paper as a contrast to procurement-led changes to projects driven by clients. Procurement-led initiatives try to induce changes to behaviour through market governance. Relationship marketing and management proactively change organizational behaviour, the enterprise taking responsibility for its own destiny. Investment and resource allocation, and organizational behaviour have posed constraints, particularly concerning service continuity in construction. Overcoming these constraints offers opportunities for delivering service improvements and adding value for clients and yielding further increases in repeat business and increasing profitability. Relationship marketing is the conceptual starting...
The mechanism of action of Clostridium difficile enterotoxin A (CA), of Escherichia coli enterotoxin (STa) and of cholera toxin (CT), which are known to cause severe diarrhea, were studied in a preparation of ligated jejunal loops of anesthetized rats in vivo. The toxins were administered intraluminally. Pharmacological agents, which were tested for their potency to influence toxin-related effects, were administered subcutaneously. Net fluid transport was determined gravimetrically, prostaglandin (PG) E_2-output into the lumen, cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) contents in the mucosa were measured by radioimmunoassay, serotonin-(5-HT)-output into the lumen was determined by high performance liquid chromatography. The histopathological effects of CA and CT were examined by light- and scanning electron microscopy. All three toxins caused net fluid secretion (FS). 5-HT_2-(ketanserin) and 5-HT_3-receptor antagonists (tropisetron, ondansetron, ...
Full text: The maturation of chicken forebrain is protracted and occurs well after synapse formation providing a good model for studying mechanisms of brain maturation. Using microslices from immature (10 day) and adult chicken forebrain prepared after decapitation, we have examined functional properties of NMDA and AMPA receptors by measuring agonist-induced uptake of "4"5Ca"2"+ . The rate and extent of NMDA induced "4"5Ca"2"+ accumulation decreased during maturation with no change in EC_5_0. The rate and extent of the AMPA inducedresponse also decreased with a 60-fold increase in EC_5_0. However, the total NMDA receptor content did not change as indicated by 3 H-MK801 binding and NR1 immunoreactivity in P2 fractions. Similarly, there was no change in the B_m_a_x of "3H-AMPA, though there was a two-fold increase in K_D, and little or no change in the immunoreactivity in GluR1, 2, 2/3 or 4. These ...
We carried out a feeding study in rats aimed at extending our aboservations of contaminant-induced immunosuppression in harbour seals. Two herring batches were freeze-dried, supplemented and fed to female adult PVG rats for a period of 4 1/2 months. Daily contaminant intakes of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxic equivalents (TEQ) were estimated to be 0.3 ng/kg body weight and 1.6 ng/kg in the Atlantic and Baltic groups, respectively. At the end of the feeding experiment, no contaminant-related changes in spleen CD{sub 4}{sup +}/CD{sub 8}{sup +} cellularity, natural killer cell activity, or mitogen-induced proliferative responses of thymus or spleen cells could be detected. However, total thymocyte numbers and thymus CD{sub 4}{sup +}/CD{sub 8}{sup +} ratios were reduced in the Baltic group. A novel model was established to assess the specific T-cell response to rat cytomegalovirus (RCMV). ...
It is one of the most important subjects to estimate the flow-related stability of the heat exchanger tubes. A large scale model steam generator has been developed to verify the stability of the tubes in the Japanese PWR steam generators for the two-phase flow-induced vibration and to accumulate related technical data of thermal-hydraulic and flow-induced vibration of U-bend tube bundle. The model steam generator has 230 U-bend tubes of 46 different radius and 5 columns for each of practical diameter and material, and the anti vibration bars are inserted into each spacing between tube arrays. The freon R123 has been used as the secondary side fluid in stead of water-steam two-phase. In the test, void fraction and interfacial velocities in U-bend and straight tube-bundle are measured with bi-optical probes, and vibration responses of some selected tubes are measured with strain gauges and accelerators. It is verified that ...
Glutathione (GSH) depletion sensitizes human lung carcinoma (A549-T27) cells to the cytotoxic effects of Cd++. The effects of GSH depletion on Cd++ accumulation and Cd++-induced metallothionein (MT) content were investigated to determine the possible role of these Cd++ responses in the sensitization process. Cellular GSH was depleted to 20% to 25% of control levels with buthionine sulfoximine (BSO), or diethyl maleate (DEM), respectively. Neither treatment significantly affected Cd++-induced accumulation of exogenous 35s-cysteine into intracellular MT in a dose-dependent fashion. The results indicate that neither enhanced Cd++ accumulation nor reduced MT synthesis plays a primary role in affecting enhanced Cd++ cytotoxicity in A549 cells with reduced GSH levels. Although BSO inhibition of GSH synthesis enhanced MT synthesis, it sensitized the cells to Cd++, which suggests an additive effect of GSH and MT in cadmium ...
Arachidonic acid is metabolized by means of P450 isoenzyme(s) to form epoxyeicosatrienoic acids (EETs) and their corresponding dihydroxy derivatives (DHETs). In the present study, we established the presence in human urine of 8,9-, 11,12-, and 14,15-EETs and their corresponding DHETs by developing quantitative assays and using negative ion, chemical ionization GC/MS and octadeuterated internal standards. Urinary excretion of 8,9- and 11,12-DHET increased in healthy pregnant women compared with nonpregnant female volunteers. By contrast, excretion of 11,12-DHET and 14,15-DHET, but not the 8,9-DHET regioisomer, increased even further in patients with pregnancy-induced hypertension. Intravenous administration of (3H)14,15-EET to three dogs markedly increased its DHET in plasma. The terminal half-life ranged from 7.9-12.3 min and the volume of distribution (3.5-5.3 liters) suggested limited distribution outside the plasma compartment. Negligible radioactivity was ...
Exercise training associated with robust conditioning can be useful for the study of molecular mechanisms underlying exercise-induced cardiac hypertrophy. A swimming apparatus is described to control training regimens in terms of duration, load, and frequency of exercise. Mice were submitted to 60- vs 90-min session/day, once vs twice a day, with 2 or 4% of the weight of the mouse or no workload attached to the tail, for 4 vs 6 weeks of exercise training. Blood pressure was unchanged in all groups while resting heart rate decreased in the trained groups (8-18%). Skeletal muscle citrate synthase activity, measured spectrophotometrically, increased (45-58%) only as a result of duration and frequency-controlled exercise training, indicating that endurance conditioning was obtained. In groups which received duration and endurance conditioning, cardiac weight (14-25%) and myocyte dimension (13-20%) increased. The best conditioning protocol to promote physiological ...
Many hormones elicit effects on target cells by stimulating the enzyme phospholipase-C, which catalyzes the hydrolysis of phosphoinositides to the intracellular second messengers diacylglycerol and inositol phosphates. The present study examined the roles of FSH and guanine nucleotide-binding proteins (G-proteins) in regulating the hydrolysis of phosphoinositides in Sertoli cells. Sertoli cell cultures prepared from 16- to 18-day-old rats were incubated for 24 h with myo-[2-3H] inositol to label endogenous phospholipids. Treatment of cells from 0.5-20 min with preparations of ovine FSH ranging in potency from 1-60 times that of NIH FSH S1 did not affect accumulation of inositol phosphates. Levels of total [3H]inositol phosphates [[3H]inositol mono-, di-, and triphosphates (IP, IP2, and IP3)] in FSH-treated cultures was 75-120% the levels in control cultures over the various time intervals studied. Addition of testosterone and the combination of testosterone plus retinoic acid, agents ...
The blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) signal response to neural stimulation is influenced by many factors that are unrelated to the stimulus. These factors are physiological, such as the resting venous cerebral blood volume (CBV(v)) and vessel size, as well as experimental, such as pulse sequence and static magnetic field strength (B(0)). Thus, it is difficult to compare task-induced fMRI signals across subjects, field strengths, and pulse sequences. This problem can be overcome by normalizing the neural activity-induced BOLD fMRI response by a global hypercapnia-induced BOLD signal. To demonstrate the effectiveness of the BOLD normalization approach, gradient-echo BOLD fMRI at 1.5, 4, and 7 T and spin-echo BOLD fMRI at 4 T were performed in human subjects. For neural stimulation, subjects performed sequential finger movements at 2 ...
Red light stimulates germination in the spores of Onoclea sensibilis L. Phytochrome is confirmed to be the photoreceptor pigment in the germination response by demonstrating red-far-red photoreversibility. External Ca/sup 2 +/ is required for this response with a threshold at a submicromolar concentration. Red light stimulates an increase in the total concentration of intracellular calcium in the spores as determined by atomic absorption spectroscopy. Subsequent exposure to far-red light inhibits the red light-induced increase in intracellular calcium. The majority of the increase occurs 5 minutes after the onset of irradiation. The calcium-antagonist, La/sup 3 +/ inhibits both germination and the red light-induced increase in intracellular calcium. Using /sup 31/P-nuclear magnetic resonance spectroscopy, the author tested the hypothesis that a sustained increase in intracellular pH contributes to the ...
The spike (S) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) has two major functions: interacting with the receptor to mediate virus entry and inducing protective immunity. Coincidently, the receptor-binding domain (RBD, residues 318-510) of SAR-CoV S protein is a major antigenic site to induce neutralizing antibodies. Here, we used RBD-Fc, a fusion protein containing the RBD and human IgG1 Fc, as a model in the studies and found that a single amino acid substitution in the RBD (R441A) could abolish the immunogenicity of RBD to induce neutralizing antibodies in immunized mice and rabbits. With a panel of anti-RBD mAbs as probes, we observed that R441A substitution was able to disrupt the majority of neutralizing epitopes in the RBD, suggesting that this residue is critical for the antigenic structure responsible for inducing protective immune ...
Either airway cooling or sulfur dioxide (SO/sub 2/) can induce bronchoconstriction in many asthmatics. Whether these two stresses act synergistically is a question with important public health implications. Eight young adult asthmatic volunteers were exposed to SO/sub 2/ at 0.0, 0.2, 0.4, and 0.6 ppm, during 5 min heavy exercise at 5 degrees C, both with high (approximately 85%) and with low (approximately 50%) relative humidity. Physiologic response increased with increasing SO/sub 2/ concentration but did not vary significantly with humidity. Symptom response was marginally greater at low than at high humidity. Twenty-four asthmatics were exposed similarly to clean air and to 0.6 ppm SO/sub 2/, at 5 degrees C and also at 22 degrees C, always at high relative humidity. For this group, physiologic and clinical responses to SO/sub 2/ (in excess of responses to clean air) were highly ...
In a given species, injected opioid peptides usually cause changes in temperature similar to those caused by nonpeptide opioids. The main effect in those species most studied, the cat, rat, and mouse, is an increase in the level about which body temperature is regulated; there is a coordinated change in the activity of thermoregulatory effectors such that hyperthermia is produced in both hot and cold environments. Larger doses may depress thermoregulation, thereby causing body temperature to decrease in the cold. Elicitation of different patterns of response over a range of environmental temperatures and studies with naloxone and naltrexone indicate that stimulation of a number of different receptors by both peptide and nonpeptide opioids can evoke thermoregulatory responses. ..beta..-Endorphin is readily antagonized by naloxone whereas methionine-enkephalin can act on naloxone-insensitive receptors. Moreover, synthetic peptide analogs do not ...
Mitotic delay is described as a classical response to radiation; however, circadian rhythmicity in cell division in vivo has not been considered by many authors. The present study investigated the relation between fluctuations reported as mitotic delay and recovery in vivo and circadian oscillations in mitotic index in mouse corneal epithelium. One aspect involved single doses (approximately 600 rad) given to mice at different circadian stages. The normal circadian rhythm in cell division was never obliterated. Inhibition of mitosis was evident but unpredictable, ranging from 6 to 15 hr after irradiation. Recovery was evident only during the daily increase in mitotic index of controls. The classical interpretation of recovery from mitotic delay may be in an in vitro phenomenon not reflecting in vivo responses, which are apparently strongly circadian stage dependent. The second portion of the study demonstrated a ...
Blood flow changes in the periodontal ligament (PDL) were measured indirectly by monitoring the local clearance of /sup 125/I/sup -/ during electric sympathetic nerve stimulation or close intra-arterial infusions of either noradrenaline (NA) or adrenaline (ADR) before and after administration of phentolamine (PA), phenoxybenzamine (PBZ) or Idazoxan (RX). At the doses used in the present study, PA was the only antagonist that significantly reduced the blood flow decrease seen on activation of sympathetic fibers, although PBZ also reduced this response. Idazoxan, however, did not induce the consistent effect on blood flow decreases seen on sympathetic activation. All three ..cap alpha..-adrenoceptor antagonists almost abolished the effects of exogenously administered NA and ADR. The results suggest the presence of functional post-junctional adrenoceptors of both the ..cap alpha.. 1 and ..cap alpha.. 2 subtypes in the sympathetic regulation of the ...
The aim of the present study was to test a mathematical model of the biochemical processes in the parathyroid glands responsible for the secretion of parathyroid hormone resulting from extracellular calcium reduction. A double exponential curve described the parathyroid hormone secretion induced by rapid lowering of blood-ionized calcium in humans with normal as well as abnormal parathyroid tissue. Our data show that it was possible to establish a simple mathematical model of the parathyroid hormone response to blood-ionized calcium lowering, sufficient to fit experimental data obtained from patients with abnormal and normal parathyroid tissue. The fitted parameters showed no significant differences between patients with insulin-dependent diabetes mellitus and controls. In primary hyperparathyroidism, the parathyroid hormone production and steady-state transport across the cell membrane were increased, probably due to the ...
pT181 is a naturally-occurring 4437 basepair (bp) plasmid isolated from Staphylococcus aureus which encodes inducible resistance to tetracycline (Tc). The DNA sequence data has identified three open reading frames (ORFs). The largest ORF B, has been found to be responsible for the Tc resistance phenotype of pT181. Since most Tc resistance systems appear to be regulated by an effector protein and a repressor protein, several Bal 31 deletion mutants of pT181 were constructed and analyzed in an effort to identify the elements involved in Tc resistance. Two transcomplementing groups of mutants were identified within the tet gene. The mechanism of Tc resistance was studied by assaying the accumulation of (7-/sup 3/H) Tc by Tc sensitive cells, and uninduced and induced pT181-containing cells. A sharp decrease in accumulation of the drug after an initial increase was observed in Tc induced pT181-containing ...
Shewanella oneidensis MR-1 is a model environmental organism that possesses diverse respiratory capacities, including the ability to reduce soluble Cr(VI) to sparingly soluble, less toxic Cr(III). Effective bioremediation of Cr-contaminated sites requires knowledge of the molecular mechanisms and regulation of heavy metal resistance and biotransformation by dissimilatory metal-reducing bacteria. Towards this goal, our ERSP-funded work is focused on the identification and functional analysis of genes/proteins comprising the response pathways for chromate detoxification and/or reduction. Previous transcriptomic profiling and whole-cell proteomic analyses implicated the involvement of a functionally undefined DNA-binding response regulator (SO2426) and a putative azoreductase (SO3585) in the chromate stress response of MR-1. Here we describe a detailed functional analysis of SO2426 and SO3585 in order to begin to understand ...
We have observed significant differences in the response to ionizing radiation of two closely related human cell lines, and now compare the effects on these lines of both low and intermediate LET radiation. Compared to TK6, WTK1 has an enhanced X-ray survival, and is also more resistant to cell killing by {alpha}-particles. The hprt locus is more mutable in WTK1 than in TK6 by both X-rays and {alpha}-particles. WTK1 is also more mutable by {alpha}-particles than by X-rays at the hprt locus. X-ray-induced mutation at the heterozygous tk locus in WTK1 is about 25 fold higher than in TK6, while {alpha}-particle-induced mutation is nearly 50 fold higher at this locus. Also, the slowly growing tk- mutants, which comprise the majority of spontaneous and X-ray-induced tk- mutants of TK6, were not induced significantly by {alpha}-particles. Previously, we showed that TK6 has a reduced ...
Candoxin (PDB #1JGK), a three-finger neurotoxin from Bungarus candidus venom, inhibits post-synaptic neuromuscular and neuronal alpha7nACh-receptors, and induces delayed cell-death throughout the glial population. When applied to cultured human glial cell lines, candoxin (CDX) induced cell death in a concentration (EC(50) approximately 1muM) and time dependent manner. Results of TUNEL-histochemistry further confirm CDX-induced brain (hippocampus, frontal cortex, and temporal regions) damage when administered intracerebroventricularly (i.c.v) in adult mice. In this study, we explored differential gene expression profiles following exposure of human glial (Hs 683) cell lines to CDX at various time intervals using Affymetrix-GeneChips. By means of MAS and GeneSpring analyses, 105 genes whose expression was significantly (P<0.01) altered by at least 3-fold were selected. Results of the genome analysis reveal that the ...
In-reactor testing of bolt-loaded compact tension specimens was performed in 360 C water to determine the irradiation-assisted stress corrosion cracking (IASCC) behavior of HTH Alloy X-750 and direct-aged Alloy 625. New data confirm previous results showing that high irradiation levels reduce SCC resistance in Alloy X-750. Heat-to-heat variability correlates with boron content, with low boron heats showing improved IASCC properties. Alloy 625 is resistant to IASCC, as no cracking was observed in any Alloy 625 specimens. Microstructural, microchemical and deformation studies were performed to characterize the mechanisms responsible for IASCC in Alloy X-750 and the lack of an effect in Alloy 625. The mechanisms under investigation are: boron transmutation effects, radiation-induced changes in microstructure and deformation characteristics, and radiation-induced segregation. Irradiation of Alloy X-750 caused significant ...
Glycyrrhiza glabra root is one of the common traditional Chinese medicines and used as flavoring and sweetening agents for tobaccos, chewing gums, candies, toothpaste and beverages. While glycyrrhizin is one of the main components in the extract of G. glabra root and has been characterized, the other components have not been well characterized. The mechanism of growth activation of breast cancer MCF-7 cells, including the activation of Erk1/2 and Akt, and the transcriptional regulation of estrogen-responsive genes, was examined by means of sulforhodamine B, luciferase reporter gene, real-time RT-PCR and Western blotting assays after the induction of the cells with the extract of G. glabra root. The extract has similar activity to that induced by 17beta-estradiol (E(2)), although glycyrrhizin did not show such an activity. Moreover, the estrogen receptor alpha-dependent neurite outgrowth induced by the extract was similar to ...
The IRG protein Irgm3 preserves cell survival during coxsackievirus B3 (CVB3) infection. However, the molecular mechanisms are not clear. Here, we examined the effect of Irgm3 expression on ER stress triggered by pharmacological agents or CVB3 infection. In Tet-On/Irgm3 HeLa cells, Irgm3 expression suppressed either chemical- or CVB3-induced upregulation of glucose-regulated protein78. Further, Irgm3 strongly inhibited the activation of both the PERK and ATF6 pathways of ER stress responses, which further led to the diminished phosphorylation of eIF2?, reduced cleavage/activation of transcription factor SREBP1 and attenuated induction of proapoptotic genes CHOP and GADD34. These data were further supported by experiments using Irgm3 knockout mouse embryonic fibroblasts, in which the ER stress induced by CVB3 was not relieved due to the lack of Irgm3 expression. In addition, the tunicamycin-triggered ER stress promoted the ...
Numerous laboratory investigations have shown that sulfur dioxide (SO/sub 2/) induces bronchoconstriction and respiratory symptoms in exercising asthmatics. These effects appear to depend on dose rate (the product of exposure concentration and ventilation rate), and may occur at dose rates attainable during outdoor exercise in SO/sub 2/-polluted communities. Effects are rapid in onset, requiring no more than 5 min of exercise during exposure. Thus they may be induced by transient elevations of SO/sub 2/ levels, which may occur near large pollution sources even when longer-term average concentrations meet existing air quality standards. Even very mild asthmatics typically are far more sensitive to SO/sub 2/ than healthy volunteers. The authors discuss an investigation designed to expand and improve the dose-response information on SO/sub 2/. In comparison to earlier work it employed a larger, clinically more diverse ...
Abstract in english BACKGROUND: Severe pathogenic infection triggers excessive release of cytokines as part of the massive inflammatory response associated with septic shock. OBJECTIVES: To investigate the protective effect of caffeic acid phenethye ester (CAPE) against lipopolysaccharide (LPS) induced endotoxemia, hepatic and neuronal damage and the associated systemic inflammatory response (SIR). METHODS: Fifty male Wister rats were divided into: control, LPS, and CAPE+LPS groups. Plasma c (more) oncentrations of various cytokines, including TNF-?, IL-1?, IL-1?, IL-6, IL-4, IL-10, and sICAM-1 were evaluated. In addition, the histopathological changes in the hepatic and neural cells were assessed. RESULTS: The LPS group showed high inflammatory cytokines and sICAM-1 levels reflecting the presence of SIR. Hepatocyte necrosis, apoptosis, extensive hemorrhage and inflammatory cellular infiltration together with brain ...
The electronic band structure, transport properties, and lattice dynamics in AuX_2 (X = Al, Ga and In) under high pressure have been extensively studied with full potential linearized augmented plane wave and pseudopotential plane wave methods. The theoretical results for the electronic band structure and Fermi surface reveal pressure-induced electronic topological transitions (ETTs) in AuGa_2 and AuIn_2, while they are absent in AuAl_2, in excellent agreement with the experimental observations. Moreover, calculations of the transport properties at different pressures reveal subtle changes in the band structure close to the Fermi surface of the three intermetallic compounds. It is clear that the anomalies in transport properties are due to ETTs. Interestingly, a pressure-induced soft transverse acoustic (TA) phonon mode is identified only in AuGa_2. The TA phonon instability at the Brillouin zone boundary L point might be ...
In this paper the structural and functional changes of gamma irradiated bovine hemoglobin are presented. Aqueous solutions/1%/of HbO_2 were irradiated in air with doses ranging from 1 to 4 Mrad. Isoelectric focusing indicated change of the charge of irradiated hemoglobin. The isoelectric point of hemoglobin was displaced towards more acid values with increasing doses, up from 1 Mrad. Fingerprint analysis and peptide column chromatography of irradiated hemoglobin demonstrated disturbances increasing with the dose. These changes were confirmed by amino acid analysis which showed that Cys, Met, Trp, His, Pro and Tyr residues were destroyed or modified following irradiation. At doses exceeding 1 Mrad the irradiated solutions of hemoglobin showed a decrease of heme-heme interaction and an increase of affinity for oxygen. Differences observed in oxygen-dissociation curves seem to be correlated with the radiation induced destruction of amino acid residues which are ...
Emerging evidence suggests that E3 ligases play critical roles in diverse biological processes, including innate immune responses in plants. However, the mechanism of the E3 ligase involvement in plant innate immunity is unclear. We report that a rice gene, OsBBI1, encoding a RING finger protein with E3 ligase activity, mediates broad-spectrum disease resistance. The expression of OsBBI1 was induced by rice blast fungus Magnaporthe oryzae, as well as chemical inducers, benzothiadiazole and salicylic acid. Biochemical analysis revealed that OsBBI1 protein possesses E3 ubiquitin ligase activity in vitro. Genetic analysis revealed that the loss of OsBBI1 function in a Tos17-insertion line increased susceptibility, while the overexpression of OsBBI1 in transgenic plants conferred enhanced resi...
Limitations of traveling wave relaying schemes for protection of overhead extra-high voltage transmission lines are investigated. A method of analysis of traveling wave phenomena for three phase transmission lines is developed in which the interdependent phase voltages and currents are decoupled into their modal counterparts, which are approximately independent. A time domain digital simulation program is used to solve the modal transmission line equations to obtain the fault induced traveling waves detected at the relay location. The frequency dependence of the aerial modes is ignored but their losses are included. A lumped element analysis method, originally developed for transient analysis of lossy coaxial cables, is adapted here to obtain approximate solution for the fault induced traveling waves of the ground mode. Excellent agreement is found between the results obtained by this method and frequency domain methods. This time-domain method ...
Previous behavioral and pharmacological studies have implicated endorphins in radiation-induced locomotor hyperactivity of the C57BL/6J mouse. However, the endogenous opiate(s) responsible for this behavioral change have not been identified. The present study measured beta-endorphin-like immunoreactivity (beta-END-LI) in brain, blood, and combined brain and pituitary samples from irradiated and sham-irradiated C57BL/6J mice. After radiation exposure, levels of beta-END-LI decreased significantly in the brain. A similar, but not statistically significant, decline was measured in combined brain and pituitary samples. Concentrations of blood beta-END-LI were not changed by irradiation. These radiogenic changes in beta-END-LI are in some ways similar to those observed after other stresses. However, radiation-induced locomotor hyperactivity may be mediated more by alterations of beta-END-LI in the brain than in the periphery. ...
Fe-Cu binary alloys are often used to mimic the behaviour of reactor pressure vessel steels. Their study allows identifying some of the defects responsible for irradiation-induced hardening. But recently the influence of manganese and nickel in low-Cu steels has been found to be important as well. In contrast with existing models found in the literature, which predict that hardening saturates after a certain dose, Fe alloys containing nickel and manganese irradiated in a material test reactor (BR2) show a continuous increase of hardening, up to doses equivalent to about 40 years of operation. Considerations based on positron annihilation spectroscopy analyses suggest that the main objects causing hardening in Cu-free alloys are most probably self-interstitial clusters decorated with manganese. In low-Cu reactor pressure vessel steels and in Fe-CuMnNi alloys, the main effect is still due to Cu-rich precipitates at low doses, but the role of ...
Biomonitoring of human populations for exposure to genotoxic/clastogenic agents in the environment or the workplace must depend upon statistical tests for elevations in the frequencies of the biological endpoints being monitored, usually chromosomal aberrations (CA), micronuclei (MN), or sister chromatid exchanges (SCE) in peripheral blood lymphocytes. Statistical tests are based, in turn, upon certain assumptions regarding the distribution of the test statistic. When they are often not recognized as such, tests of significance can be in error, and any conclusion drawn that there is or is not a statistically significant difference between one population sample and another maybe erroneous. In population monitoring this means either false negatives or false positives can result and it is hard to know which is worse. Furthermore, even the intelligent design of studies whose object is to test for an elevated level in an exposed population must depend upon prior knowledge of the nature of ...
Transient-enhanced diffusion (TED) during thermal annealing of ion-implanted B in Si is well established and attributed to the ion-induced, excess interstitials. On the other hand, the mechanism to account for TED of B in preamorphized (PA) Si remains unclear. Enhanced diffusion of the B persists in regrown layers even though the ion-induced interstitial defects responsible for TED in B{sup +}-only implanted Si are eliminated following regrowth. To test the hypothesis that TED in PA Si results from the {open_quotes}excess{close_quotes} interstitial-type defects below the amorphous-crystalline (a-c) interface, a buried PA layer has been recrystallized from the surface inward to the SiO{sub 2} interface of silicon-on-insulator material to eliminate all possible sources of excess interstitials. The effect on B diffusion and the role of the residual interstitial-type defects will be discussed. {copyright} {ital 1999 American ...
The identification of genes influencing sensitivity to stimulants and opioids is important for determining their mechanism of action and may provide fundamental insights into the genetics of drug abuse. We used a panel of C57BL/6J (B6; recipient)x A/J (donor) chromosome substitution strains (CSSs) to identify quantitative trait loci (QTL) for both open field activity and sensitivity to the locomotor stimulant response to methamphetamine (MA). Mice were injected with saline (days 1 and 2) and MA (day 3; 2 mg/kg i.p.). We analyzed the total distance traveled in the open field for 30 min following each injection. CSS-8, -11 and -16 showed reduced MA-induced locomotor activity relative to B6, whereas CSS-10 and -12 showed increased MA-induced locomotor activity. Further analysis focused on CSS...
Although low-energy ion radiation has been proven to have a wide range of biological effects and led to fruitful achievements as a new mutagenic source for genetic modification, there still exist some disputes about its mutagenic mechanisms because of its short-penetrating property. In present research, Arabidopsis thaliana transgenic for GUS recombination substrate was used to evaluate the genomic instability induced by irradiations of alpha particle (3.3MeV) and Low-energy-Argon ion (30 KeV). A pronounced effects of alpha particle irradiation to Arabidopsis thaliana seedlings and Argon ion irradiation to seeds on the somatic homologous recombination frequency (sHRF) were reported. The sHRFs increased 1.88-fold and 2.42-fold, respectively, which indicated that the short-penetrating radiation could effectively induce the plant genomic instability in either dry seeds or seedlings with active metabolism. The local alpha particle irradiation of ...
Radiation hardening and radiation-induced chromium (Cr) depletion were related to intergranular stress corrosion cracking (IGSCC) response among various stainless steels (SS). Available data on neutron-irradiated materials were analyzed and correlations developed between fluence, yield strength, grain-boundary Cr concentration, and cracking susceptibility in high-temperature water environments. Large heat-to-heat differences in the critical fluence (0.2 neutrons/cm"2 to 2.5 x 10"2"1 neutrons/cm"2) for IGSCC were documented. Variability often was consistent with yield strength differences among irradiated materials. IGSCC correlated better to yield strength than to fluence for most heats, suggesting a possible role for radiation-induced hardening (and microstructure) on cracking. However, isolated heats revealed a wide range of yield strengths (450 MPa to 800 MPa) necessary to promote IGSCC which could not be explained by ...
Adolescent exposure to anabolic androgenic steroids (AAS) alters the development and activity of the glutamate neural system in the latero-anterior hypothalamus (LAH) in hamsters (Mesocricetus auratus); that is, an important neural component of the adolescent AAS-induced aggressive response. In this article, we used retrograde tracing to investigate glutamate-specific alterations in the connections between the LAH and several other nuclei implicated in adolescent AAS-induced aggression. Briefly, hamsters were treated with AAS or sesame-oil control during adolescence and then microinjected with retrograde tracer into the medial amygdala (MeA), lateral septum (LS), or bed nucleus of the stria terminalis (BNST). Brains were then processed for vesicular glutamate transporter 2 (VGLUT2) and examined for AAS-induced changes in the number VGLUT2 cells containing retrograde tracer (VGLUT2/tracer) within the ...
Flow-induced vibration is an important concern to the designers of heat exchangers subjected to high flows of gases or liquids. Two-phase cross-flow occurs in industrial heat exchangers, such as nuclear steam generators, condensers, and boilers, etc. Under certain flow regimes and fluid velocities, the fluid forces result in tube vibration and damage due to fretting and fatigue. Prediction of these forces requires an understanding of the flow regimes found in heat exchanger tube bundles. Excessive vibrations under normal operating conditions can lead to tube failure. Relatively little information exists on two-phase vibration. This is not surprising as single-phase flow induced vibration; a simpler topic is not yet fully understood. Vibration in two-phase is much more complex because it depends upon two-phase flow regime, i.e. characteristics of two-phase mixture and involves an important consideration, which is the void fraction. The effect of ...
Irradiation with a single dose of 30 Grey on the basal regions of the lungs of Sprague-Dawley rats induced a peribronchial and alveolar inflammation. Infiltration of mast cells in the edematous alveolar interstitial tissue and also in the peribronchial tissue were characteristic features of the lesion. The appearance of mast cells was already seen 4 wk after irradiation and by weeks 6 to 8 there was a heavy infiltration. The staining properties suggested that they were connective tissue-type mast cells. The infiltration of mast cells was paralleled by an accumulation of hyaluronan (hyaluronic acid) in the alveolar interstitial tissue 6 and 8 wk after irradiation. The recovery of hyaluronan (HA) during bronchoalveolar lavage (BAL) of the lungs also increased at this time. Treatment with a mast cell secretagogue, compound 48/80, induced a distinct reduction of granulated mast cells in the alveolar tissue. Regular treatment with compound 48/80 ...
The two-compartment radioassay for microbial kinetics based on continuous measurement of the {sup 14}CO{sub 2} released by bacterial metabolism of 14C-labeled substrate offers a valuable approach to testing the potency of antimicrobial drugs. By using a previously validated radioassay with gram-positive and gram-negative bacteria, a group of protein synthesis inhibitors was evaluated for their effect on microbial growth kinetics. All tested drugs induced changes in both the slopes and intercepts of the growth curves. An exponential growth model was applied to quantify the drug effect on the processes of bacterial {sup 14}CO{sub 2} liberation and cell generation. The response was measured in terms of a generation rate constant. A linear dependence of the generation rate constant on the dose of spectinomycin was observed with Escherichia coli. Sigmoidal-shaped curves were found in the assays of chloramphenicol and tetracycline. The implications ...
Eight patients who had received megavoltage therapy for Cushings' disease 5-12 years previously have been reviewed. The long term response to this therapy was assessed with respect to efficacy of treatment in inducing continued remission and disturbance of hypothalamic-pituitary function. One patient showed clear evidence of relapse of Cushings' disease. One patient had unequivocal hypopituitarism. Basal levels of growth hormone (GH), TSH, LH, and FSH were not statistically different from controls, but provocative testing revealed significant abnormalities of response of cortisol/ACTH, GH, prolactin and LH. Six out of eight patients had absent diurnal cortisol variation and five patients had elevated serum prolactin levels. Thus, in this group of patients normal pituitary-adrenal function has not been satisfactorily restored. It is clear that significant disturbances of hypothalamic-pituitary function follow megavoltage ...
Eight patients who had received megavoltage therapy for Cushings' disease 5-12 years previously have been reviewed. The long term response to this therapy was assessed with respect to efficacy of treatment in inducing continued remission and disturbance of hypothalamic-pituitary function. One patient showed clear evidence of relapse of Cushings' disease. One patient had unequivocal hypopituitarism. Basal levels of growth hormone (GH), TSH, LH, and FSH were not statistically different from controls, but provocative testing revealed significant abnormalities of response of cortisol/ACTH, GH, prolactin and LH. Six out of eight patients had absent diurnal cortisol variation and five patients had elevated serum prolactin levels. Thus, in this group of patients normal pituitary-adrenal function has not been satisfactorily restored. It is clear that significant disturbances of hypothalamic-pituitary function ...
Bone loss associated with estrogen depletion is well documented in cancellous bone but less well characterized in cortical bone. The effects of ovariectomy on the aged beagle skeleton were studied by histomorphometric analysis of the cortical bone in sequential rib biopsies. Biopsies were taken from each ovariectomized or sham-operated dog at the time of surgery and at 1, 4, and 8.5 months after surgery. Just prior to each postoperative biopsy, tetracycline, calcein, and xylenol orange, respectively, were administered by a fluorochrome labeling procedure (2d-10d-2d) to provide markers of bone formation. Analysis of sequential rib biopsies provided a means to follow the ovariectomy response over time and to compare each animal against its own baseline. Though ovariectomy did not influence histomorphometric indices at 1 month after surgery, a transient increase in cortical bone formation occurred thereafter, with a sixfold increase over that of sham-operated dogs at ...
Peeled Avena sativa coleoptile sections have been used to study the control of solute uptake under conditions where the uptake is not limited by the cuticular barrier. In the presence of 2% sucrose, auxin enhances the rate at which the total osmotic solutes increase, but this appears to be a response to the increased growth rate, inasmuch as the auxin effect is eliminated when growth is inhibited osmotically. When sections are incubated in sucrose or in 10 millimolar NaCl, the osmotic concentration increases until a plateau is reached after 8 to 24 hours. Auxin has no effect on the initial rate of increase in osmotic concentration. This difference in steady-state osmotic concentration is, in part, a response to auxin itself, as it persists when auxin-induced growth is inhibited osmotically. The upper limit for osmotic concentration does not appear to be determined by the turgor pressure, inasmuch as a combination of sucrose ...
A modified boundary element approach was used to analyze the response of offshore piles subjected to external soil movements. The computer model employed to solve the pile-soil problem was able to model pile head and tip loading, and loading caused by lateral movement of soil. A nonlinear pile-soil interface element with the ability to represent a hardening or softening plastic response prior to reaching an ultimate state was incorporated. With the program, 4 failure modes can be determined: flow of the soil slide past an intact stationary pile; rotation of the pile with the soil at failure along the full pile length; translation of the pile with the sliding soil, resulting in failure of the supporting soil; and the long-pile mode, in which the maximum bending moment in the pile reaches the yield moment of the pile before complete development of the other 3 modes. Theoretical solutions for a realistic hypothetical offshore pile subjected to ...
We report biological changes at several UK Acid Waters Monitoring Network lakes and streams that are spatially consistent with the recovery of water chemistry induced by reductions in acid deposition. These include trends toward more acid-sensitive epilithic diatom and macroinvertebrate assemblages, an increasing proportional abundance of macroinvertebrate predators, an increasing occurrence of acid-sensitive aquatic macrophyte species, and the recent appearance of juvenile (<1 year old) brown trout in some of the more acidic flowing waters. Changes are often shown to be directly linked to annual variations in acidity. Although indicative of biological improvement in response to improving water chemistry, 'recovery' in most cases is modest and very gradual. While specific ecological recovery endpoints are uncertain, it is likely that physical and biotic interactions are influencing the rate of recovery of certain groups of organisms at ...
The inducible transcription factor NF-#kappa#B regulates divergent signaling pathways including inflammatory response and cancer development. Selective inhibitors for NF-#kappa#B signaling are potentially useful for treatment of inflammation and cancer. NF-#kappa#B is canonically activated by preferential disposal of its inhibitory protein; I#kappa#B, which suppresses the nuclear translocation of NF-#kappa#B. I#kappa#B#alpha# (a major member of I#kappa#B family proteins) is phosphorylated with an I#kappa#B kinase (IKK) and subsequently polyubiquitylated by SCF"#beta#"T"r"C"P"1 ubiquitin-ligase in the presence of E1 and E2 prior to proteasomal degradation. Here, we describe a novel inhibitor termed GS143, which suppressed I#kappa#B#alpha# ubiquitylation, but not I#kappa#B#alpha# phosphorylation, MDM2-directed p53 ubiquitylation, and proteasome activity in vitro. GS143 markedly suppressed the destruction of I#kappa#B#alpha# stimulated by ...
A testing methodology, which includes the evaluation of free sintering strain, stress-induced dimensional changes, and weight changes, was developed to determine the critical dimensional changes and thermomechanical response during presintering (i.e., before densification). The effects of organic binder burnout, decomposition of phases, and phase changes on the thermomechanical behavior of a ceramic green body, consisting of methylcellulose as a binder, gibbsite, silica, and alumina, were studied. The compressive stress-strain behavior was found to be nonlinear. The average compressive and tensile strengths of the sample at room temperature were -14.5 and 1.06 MPa, respectively. Both the compressive and tensile strengths decrease by two orders of magnitude with the increasing temperature a...
This paper seeks to investigate the liquefaction of clayey soils, a phenomenon that has been the trigger for many natural disasters in the last few decades, including landslides. Research was conducted on artificial clay?sand mixtures and natural clayey soils collected from the sliding surfaces of earthquake-induced landslides. The undrained response of normally consolidated clayey soils to cyclic loading was studied by means of a ring-shear apparatus. For the artificial clay?sand mixtures, it was found that the presence of a small amount of bentonite (?7%) would cause rapid liquefaction, while a further increase in bentonite content (?11%) produced the opposite effect of raising soil resistance to liquefaction by a significant degree. It was demonstrated that the bentonite?sand mixture wa...
Elevation of zinc protoporphyrin (ZPP) levels in the blood has served as an indicator of lead poisoning and iron deficiency anemia for many years. We have discovered that sublethal doses of whole body irradiation with x-rays also elevates ZPP 2-3-fold over normal levels. The ZPP level does not begin to increase until days 12-14 postirradiation and peaks between days 18 and 20 before returning to normal levels between days 28 and 35. Increasing the radiation dose delays the onset of the rise in ZPP, but does not affect the magnitude of the elevation. At lethal doses, ZPP elevation is not observed. Neither of the two previously described mechanisms that cause elevations of ZPP, namely iron deficiency and inhibition of ferrochelatase, are responsible for the radiation-induced elevation of ZPP. The elevation of ZPP appears to be correlated with the recovery of the hematopoietic system from radiation injury.
In Indian traditional medicine, various plants have been used widely as a remedy for treating snakebites. The aim of this study was to evaluate the effect of Tamarindus indica seed extract on the pharmacological as well as the enzymatic effects induced by V. russelli venom. Tamarind seed extract inhibited the PLA2, protease, hyaluronidase, L-amino acid oxidase and 5prime-nucleotidase enzyme activities of venom in a dose-dependent manner. These are the major hydrolytic enzymes responsible for the early effects of envenomation, such as local tissue damage, inflammation and hypotension. Furthermore, the extract neutralized the degradation of the Bb chain of human fibrinogen and indirect hemolysis caused by venom. It was also observed that the extract exerted a moderate effect on the clotting ...
Jet-driven shocks are responsible for an important fraction of the emission of the narrow-line regions (NLRs) in many classes of AGN. However, this cannot explain all observations. It is clear that the remaining sources are photoionised by the active nucleus. The 2-d hydrodynamic models from the RSAA group support an evolutionary scenario whereby the shock-excited NLRs are initially jet-driven but later, ionizing photons from the central engine replace shocks as the main excitation mechanism and shock induced star formation may also become important. In their photoionized phase, dusty and radiation-pressure dominated evolution produces a self-regulated NLR spectrum. This model aso explains the coronal emission lines and fast (3000 km s$^{-1}$) outflows seen in some Seyferts.
DFNA5 was first identified as a gene causing autosomal dominant hearing loss (HL). Different mutations have been found, all exerting a highly specific gain-of-function effect, in which skipping of exon 8 causes the HL. Later reports revealed the involvement of the gene in different types of cancer. Epigenetic silencing of DFNA5 in a large percentage of gastric, colorectal and breast tumors and p53-dependent transcriptional activity have been reported, concluding that DFNA5 acts as a tumor suppressor gene in different frequent types of cancer. Despite these data, the molecular function of DFNA5 has not been investigated properly. Previous transfection studies with mutant DFNA5 in yeast and in mammalian cells showed a toxic effect of the mutant protein, which was not seen after transfection ...
Plants use multiple defence mechanisms comprising both constitutive and inducible barriers to prevent entering of phytopathogenic micro-organisms. In many plant species one of the most efficient responses to combat attacking microbes is the rapid synthesis of antimicrobial low molecular weight phytoalexins, for example, resveratrol, 3,5,4prime-trihydroxystilbene (1). Resveratrol and its natural derivatives, however, display only moderate antimicrobial effects. Nevertheless, resveratrol may be a useful lead structure for the chemical synthesis of antimicrobials. In this study, several series of stilbenes have been synthesized, starting from the aldehydes using Wittig reactions to access the corresponding styrenes that were subjected to Mizoroki-Heck reactions to yield the stilbenes in good ...
This study describes the chemical composition of the essential oil of Artemisia maritima (Am.Oil) and the pharmacological basis for its medicinal use in gut and airways disorders. Twenty five compounds, composing 93.7% of the oil, were identified; among these, chrysanthenyl propionate and elixene were identified for the first time from any Artemisia species. The Am.Oil (0.3?1.0 mg/mL) suppressed spontaneous and high K+ (80 mM)-induced contractions in isolated rabbit jejunum, suggestive of an antispasmodic effect mediated possibly through calcium channel blockade. The calcium channel blockade activity was confirmed when pre-treatment of the tissue with Am.Oil (0.01?0.03 mg/mL) shifted the Ca++ concentration-response curves to the right, similar to verapamil and papaverine. In isolated trach...
Upcoming high-intensity laser systems will be able to probe the quantum-induced nonlinear regime of electrodynamics. So far unobserved QED phenomena such as the discovery of a nonlinear response of the quantum vacuum to macroscopic electromagnetic fields can become accessible. In addition, such laser systems provide for a flexible tool for investigating fundamental physics. Primary goals consist in verifying so far unobserved QED phenomena. Moreover, strong-field experiments can search for new light but weakly interacting degrees of freedom and are thus complementary to accelerator-driven experiments. I review recent developments in this field, focusing on photon experiments in strong electromagnetic fields. The interaction of particle-physics candidates with photons and external fields can be parameterized by low-energy effective actions and typically predict characteristic optical signatures. I perform first estimates of the accessible ...
Abstract Male infertility continues to be a clinical challenge of increasing significance. While male factors such as decreased semen quality are responsible for 25% of all infertility issues, the etiology of suboptimal semen quality is poorly understood. Many physiological, environmental, and genetic factors have been implicated, including oxidative stress. Oxidative stress is induced by reactive oxygen species (ROS), or free radicals, and although ROS are required for critical aspects of sperm function, excessive levels of ROS can negatively impact sperm quality. The origin of ROS generation, and the etiologies of increased ROS in men with suboptimal sperm quality have only recently been elucidated, offering multiple targets for potential therapy. Here, we present a critical review of th...
Bark beetles that colonize living conifers and their microbial associates encounter constitutive and induced chemical defenses of their host. Monoterpene hydrocarbons comprise a major component of these allelochemicals, and many are antibiotic to insects, fungi, and bacteria. Some bark beetle species exhaust these defenses by killing their host through mass attacks mediated by aggregation pheromones. Others lack adult aggregation pheromones and do not engage in pheromone-mediated mass attacks, but rather have the ability to complete development within live hosts. In the former species, the larvae develop in tissue largely depleted of host terpenes, whereas in the latter exposure to these compounds persists throughout development. A substantial literature exists on how monoterpenes affect b...
A numerical package called RESID has been assembled to calculate the residual stresses in VAWT blades induced during cold forming. Using a strength of materials - elementary beam theory approach, RESID models the material response with a bilinear stress-strain curve, and the cross-sectional geometry with an array of area increments. Through an iterative solution procedure residual stresses are predicted for a specified final radius of curvature or applied bending moment. RESID results are compared to theoretical solutions for simple geometries and with MARC Finite element results for VAWT blade geometries. Calculating residual stress levels, determining acceptable residual stress levels, and a method of reducing residual stresses are discussed. A complete listing and sample run are included in the appendicies.
A better understanding of the immune processes in the pathogenesis and progression of prostate cancer (CaP) may point the way towards improved treatment modalities. The challenge is to amplify immune responses to combat tumour escape mechanisms. Infection and inflammation may have a role in prostate carcinogenesis, including the newly discovered xenotropic murine leukaemia virus (XMRV). These inflammatory states damage defence mechanisms and induce a high proliferative state favouring further mutation and impaired immune surveillance. With this knowledge we are able to explore the use of immunotherapy to rejuvenate the immune system in combating CaP. Recently Sipuleucel-T, an immunotherapeutic agent for metastatic androgen independent CaP, has resulted in improved survival and might be the...
Male meadow voles housed in a long photoperiod (14 h light/day, LP) preferred female to male odors, whereas males maintained in a short photoperiod (10 h light/day, SP) did not display preferences for odors of either sex. These odor-preference patterns matched those of free-living males during spring and autumn, respectively. The preference of LP male voles for female over male odors was eliminated by gonadectomy and reinstated by treatment with testosterone. In SP males, although gonadectomy did not affect odor choices, a preference for female odors was induced by testosterone treatment. Treatment with estradiol did not alter odor preferences of LP or SP males. In conjunction with previous result, the present findings suggest that hormonal responsiveness of neural substrates that control odor preferences are sexually dimorphic and may reflect sex differences in reproductive strategies. PMID:1615048
Most gas dynamic computations in industrial ducts are done in one dimension with cross-section-averaged Euler equations. This poses a fundamental difficulty as soon as geometrical discontinuities are present. The momentum equation contains a non-conservative term involving a surface pressure integral, responsible for momentum loss. Definition of this integral is very difficult from a mathematical standpoint as the flow may contain other discontinuities (shocks, contact discontinuities). From a physical standpoint, geometrical discontinuities induce multidimensional vortices that modify the surface pressure integral. In the present paper, an improved 1D flow model is proposed. An extra energy (or entropy) equation is added to the Euler equations expressing the energy and turbulent pressure ...
Nitric oxide (NO) and related molecules such as peroxynitrite, S-nitrosoglutathione (GSNO), and nitrotyrosine, among others, are involved in physiological processes as well in the mechanisms of response to stress conditions. In sunflower seedlings exposed to five different adverse environmental conditions (low temperature, mechanical wounding, high light intensity, continuous light, and continuous darkness), key components of the metabolism of reactive nitrogen species (RNS) and reactive oxygen species (ROS), including the enzyme activities L-arginine-dependent nitric oxide synthase (NOS), S-nitrosogluthathione reductase (GSNOR), nitrate reductase (NR), catalase, and superoxide dismutase, the content of lipid hydroperoxide, hydrogen peroxide, S-nitrosothiols (SNOs), the cellular level of N...
Iron, zinc, copper and manganese are essential metals for cellular enzyme functions while cadmium, mercury and the metalloid arsenic lack any biological function. Both, essential metals, at high concentrations, and non-essential metals and metalloids are extremely reactive and toxic. Therefore, plants have acquired specialized mechanisms to sense, transport and maintain essential metals within physiological concentrations and to detoxify non-essential metals and metalloids. This review focuses on the recent identification of transporters that sequester cadmium and arsenic in vacuoles and the mechanisms mediating the partitioning of these metal(loid)s between roots and shoots. We further discuss recent models of phloem-mediated long-distance transport, seed accumulation of Cd and As and rec...
Nickel ion radiation at 500 C was shown to have a strong effect on the surface electrochemistry and intergranular corrosion (IGC) of stainless steel (SS). Measured current densities in a 1 N sulfuric acid solution at room temperature were increased at active-passive, passive, and transpassive potentials. Radiation effects on the current decay behavior and susecptibility to IGC were similar for a fine-grained (FG) S alloy and for a very large-grained (LG) SS. Radiation-induced segregation (RIS) at the surface was believed to promote higher currents at short times, whereas segregation at grain boundaries was responsible for IG attack. Analytical electron microscopy (AEM) measurements revealed chromium and iron depletion plus Ni and silicon enrichment at grain boundaries in irradiated specimens. Si enhanced dissolution at transpassive potentials, whereas Cr depletion did the same at active-passive and passive potentials.
Normal human foreskin keratinocytes cotransfected with the neomycin resistance gene and recombinant human papillomavirus (HPV) DNAs (types 16, 18, 31, and 33) that have a high or moderate association with cervical malignancy acquired immortality and contained integrated and transcriptionally active viral genomes. Only transcripts from the intact E6 and E7 genes were detected in at least one cell line, suggesting that one or both of these genes are responsible for immortalization. Recombinant HPV DNAs with low or no oncogenic potential for cervical cancer (HPV1a, -5, -6b, and -11) induced small G418-resistant colonies that senesced as did the nontransfected cells. These colonies contained only episomal virus DNA; therefore, integration of HPV sequences is important for immortalization of keratinocytes. This study suggests that the virus-encoded immortalization function contributes to the pathogenesis of cervical carcinoma.
Summaries are included of research contracts which expired prior to Dec. 31, 1960. The contracts were concerned with investigations of: electrophysiological responses of biological systems in nerve cells to irradiation with small doses of ionizing radiations; the mode of the protective action of certain sulfhydryl compounds against radiation effects on the synthesis of deoxyribonucleic acid, using tritium-labeled thymidine; development of a bubble chamber method of monitoring and dosimetry for Low fast neutron fluxes; effects of incorporated radioisotopes on the stability of genetic materials; interrelation of root and leaf absorption of radioisotopes in herbaceous plants; uptake of radioactive wastes by lowland rice from soils contaminated by irrigation water, and decontamination of the rice; and comparison between mutation rates induced by acute and chronic gamma irradiations. (B.O.G.)
Abstract In response to growing consumer concerns, developed-country governments have reduced permissible pesticide residue levels in food. Many food retailers have developed even more stringent private food safety protocols relating to pesticide use, storage and disposal and passed them on to their suppliers. Exporters in developing countries enforce these developed-country pesticide standards (DC-PS) by subjecting farmers to close monitoring. This study explores the effects of enforcing compliance with DC-PS on smallholder farmers' pesticide-related health costs. Results suggest that enforcing DC-PS encourages farmers to use protection that lowers pesticide-induced morbidity, hence reducing farmers' health costs from pesticide exposure. The study concludes that there are health benefits ...
A 65-yr-old female developed cough, fever and dyspnoea following repeated exposure to a home ultrasonic humidifier. High-resolution computed tomography showed ground-glass opacity in both lung fields. Arterial blood gas analysis gave an oxygen tension of 8.38 kPa (63 Torr). Pulmonary function testing revealed restrictive ventilatory impairment with a reduction in the diffusing capacity. The diagnosis of extrinsic allergic alveolitis (EAA) was confirmed by radiographic findings, pathological evidence of alveolitis and reproductive development by a provocation test to the humidifier water. The yeast Debaryomyces Hansenii was the only microorganism cultured from the water of the humidifier. The double diffusion precipitating test and lymphocyte proliferative response was positive for an extract of D. Hansenii, providing evidence to incriminate this fungus. This is the first described case of EAA caused by D. Hansenii. PMID:12449192
The expression of motor activity levels in response to novel situations is under complex genetic and environmental control. Several genetic loci have been implicated in the regulation of this behavioral phenotype, but their relationship to epigenetic and epistatic interactions is relatively unknown. Here, we report on a quantitative trait locus (QTL) on mouse chromosome 1 for novelty-induced motor activity in the open field, using chromosome substitution strains derived from a high active host strain (C57BL/6J) and a low active donor strain (A/J). The QTL for open field (horizontal distance moved) peaked at the location of Kcnj9, however, QTL detection was initially masked by an interplay of both grandparent genetic origin and genetic co-factors influencing behavior on chromosome 1. Our fi...
The research and development of a new type of high damping rubber damper for high rise buildings/structures to mitigate earthquake or wind-induced structural response is described in this paper. The static tests were carried out to investigate restoring force characteristics using scale model of high damping rubber damper. The repetitive tests and the temperature dependency tests were carried out to investigate variance of performance of energy absorption. It is confirmed that the damping force characteristics of the damper can be considered as that of linear viscous damping and the damper sufficiently dissipates energy for vibrations of mm order to that of generating 200% shear strain. The design methods, based on assuming linear viscous damping for the damper, has been developed. The designed values such as stiffness and damping coefficient of the damper agree well with the experimental results. (author)
The examination of the high-temperature properties of the alloy Alloy 800HT has shown that both the creep performance and the microstructure of the material can be purposefully set by the initial heat treatment. At the high temperatures applied, (700-900 C), a rapid softening process sets in induced by carbide precipitation, stabilization, and coarsening. This softening process causes creep velocities strongly accelerating as a function of duration of the heat treatment prior to the creep test. The identified cause of the softening effect is a change in particle size that could be verified by SEM and TEM. It is shown that two different carbide precipitate size classes are responsible for the softening effect. While the precipitates dectable by TEM become effective primarily via interactions with dislocations, the carbide precipitates detectable only by SEM contribute to a hardening of the grain boundaries and the matrix.(orig./CB)
Hyperspherical-harmonics method to investigate the lightest nuclei having three-cluster structure is discussed together with recent experiments. Properties of bound states and methods to explore three-body continuum are presented. The challenges created by large neutron excess and halo phenomena are highlighted. Astrophysical aspects of the "7Li + n "#-># "8Li + #gamma# reaction and the solar-boron-neutrinos problem are analyzed. Three-cluster structure of highly excited states in "8Be is shown to be responsible for extreme isospin mixing. Progress in studies of "6He- and "1"1Li-induced inclusive and exclusive nuclear reactions is demonstrated, providing information on the nature of continuum structures of Borromean nuclei.
An overview of climatic factors and impact relative to river ice engineering and science is presented. An explanation of the fundamentals of climatic change is followed by a review of direct and indirect climatic influences that govern river ice breakup and related trends. Known responses of river ice to climatic change and potential future changes to ice breakup processes are described along with the probable ecological and socio-economic consequences of these changes. Changes in engineering approaches to accommodate the present ice regime and predicted changes in climatic variables that affect river ice processes and reduce the vulnerability of infrastructure and ecosystems to climatic change are examined. Future research on the links between river ice and stream ecology is suggested to identify ecological concerns that may result from changes in river ice regimes induced by climatic change. 60 refs., 3 figs.
Glycyrrhiza glabra root is one of the common traditional Chinese medicines and used as flavoring and sweetening agents for tobaccos, chewing gums, candies, toothpaste and beverages. While glycyrrhizin is one of the main components in the extract of G. glabra root and has been characterized, the other components have not been well characterized. The mechanism of growth activation of breast cancer MCF-7 cells, including the activation of Erk1/2 and Akt, and the transcriptional regulation of estrogen-responsive genes, was examined by means of sulforhodamine B, luciferase reporter gene, real-time RT-PCR and Western blotting assays after the induction of the cells with the extract of G. glabra root. The extract has similar activity to that induced by 17b-estradiol (E2), although glycyrrhizin di...
Ab initio lattice dynamics based on linear response method are performed for high pressure phase of yttrium to describe electron-phonon coupling and subsequent superconducting behavior. The critical temperature Tc in fcc-Y increases monotonically with pressure up to 9.25 K at 31 GPa, which is quantitatively in excellent agreement with two quasihydrostatic experiments and is qualitatively compatible with recent experiments. The excellent agreement with experiments gives us a better understanding of the effective pseudopotential ?* as well as spectral function ?2(?)F(?) in yttrium. These results demonstrate that there exists strong electron-phonon coupling in Y within the studied pressure regime, and for lower pressure electron correlation becomes stronger. Generally, it is found that superconductivity in yttrium under pressure can be described quantitatively within standard theory of phonon-mediated superconductivity.
In recent years, offshore reservoirs have been developed in deeper and deeper water environments. Steel catenary risers (SCRs) are being considered in deepwater development such as Northern North Sea. SCRs used in conjunction with a semi-submersible or floating production, storage and offloading (FPSO) in deepwater harsh environments present significant design challenges. The large vertical motions at the semi or FPSO induce severe riser response, which results in difficulty meeting strength and fatigue criteria at the hang off and touch down point locations. To improve the understanding of SCR behaviour and increase the confidence in the design of such systems in deepwater harsh environments, a parametric study on a SCR connected to a semi-submersible was carried out in this paper to deal...
A new semi-submersible floating structure is proposed on which three wind turbine towers are installed. This paper presents a basic characteristic of the wave-induced motion of this semi-submersible floating structure via. numerical computations and 1/150 scaled rigid model experiments in a wave tank. In the numerical computations, nonlinear damping effect due to drag forces modeled by the Morison's formula is considered in the equation of motion, where the linear hydrodynamic forces are obtained from the Green's function model. As a result, the response characteristics around the resonant frequency region were successfully improved. In addition to such basic examination, major results of feasibility studies, including the structural stability for severe wave conditions and the long-term fatigue limit state, are presented for a realistic situation.
To determine a rat strain appropriate for carcinogenicity testing of FYX-051, a xanthine oxidoreductase inhibitor, we performed a 4-week oral toxicity study by administering 0.3, 1 and 3 mg/kg, and 1, 3 and 10 mg/kg of FYX-051 to male Sprague-Dawley (SD) and Fischer (F344) rats, respectively. Histopathology revealed that the degree of FYX-051-induced nephropathy was 3-fold stronger in SD rats than in F344 rats. Our previous study demonstrated that the key factor of species differences in FYX-051-induced nephropathy is purine metabolism. This observation led us to examine the involvement of purine metabolism in differences among two strains of rats. However, purine metabolism was proven not to be implicated as an important factor. Subsequently, other factors responsible for the strain differences were examined. FYX-051-induced increases in plasma xanthine concentrations were higher in SD rats than in ...
Breast cancer progression is characterized by inappropriate cell growth. Normal cells cease growth after a limited number of cell divisions--a process called cellular senescence-while tumor cells may acquire the ability to proliferate indefinitely (immortality). Inappropriate expression of specific oncogenes in a key cellular signaling pathway (Ras, Raf) can promote tumorigenicity in immortal cells, while causing finite lifespan cells to undergo a rapid senescence-like arrest. We have studied when in the course of transformation of cultured human mammary epithelial cells (HMEC), the response to overexpressed oncogenic Raf changes from being tumor-suppressive to tumor enhancing, and what are the molecular underpinnings of this response. Our data indicate: (1) HMEC acquire the ability to maintain growth in the presence of oncogenic Raf not simply as a consequence of overcoming senescence, but as a result of a newly discovered step in the process ...
Triphenylmethylphosphonium (TPMP+) partitions into the mitochondrial and cytosolic compartments in the rat white adipocyte in a potential-dependent fashion. The relationship between (/sup 3/H)TPMP+ distribution, intracellular cAMP generation and lipolysis in response to hormones and cAMP-mimetic compounds was examined. Half-maximal (/sup 3/H)TPMP+ efflux and glycerol release were produced by 15 and 9 nM adrenocorticotropin, 170 and 110 nM 1-epinephrine, 70 and 27 microM isobutylmethylxanthine and 800 and 750 microM dibutyryl cAMP, respectively. Hormone-stimulated cAMP generation was also correlated with (/sup 3/H)TPMP+ efflux and lipolysis in terms of concentration dependency. In kinetic experiments, glycerol release and (/sup 3/H)TPMP+ efflux in response to adrenocorticotropin or cholera toxin proceeded over a similar time course, whereas an earlier rise in cAMP generation was detected. The depolarizing effect of lipolytic compounds was ...
Self-grooming in response to the odors of conspecifics is a form of olfactory communication among meadow voles. The amount of time meadow voles spend self-grooming when they encounter the odors of conspecifics varies seasonally, with males targeting the odors of reproductively active females only during the breeding season. Other odor related behaviors in male voles such as odor preferences for conspecifics and the attractiveness of their odors to conspecifics vary seasonally as well. For male meadow voles, these behaviors are mediated by seasonal variations in testosterone (T) and prolactin (PRL) titers. The objective of this study was to determine whether seasonal differences in the amount of time male meadow voles self-groom in response to odors of conspecifics are mediated by seasonal rhythms in their circulating T and PRL titers. We tested the hypothesis that high titers of both T and PRL are necessary for reproductively active ...
Purpose/Objective: The role of programmed cell death (apoptosis) as a cellular response to cancer therapy such as radiation or chemotherapy is the subject of much study, and manipulation of the apoptotic response in tumor cells may be valuable in the treatment of a variety of cancers. Both p53 dependent and independent apoptotic pathways have been identified; p53 is mutated in at least 50 % of human cancers and a majority of radiation resistant tumors contain p53 mutations. This study is designed to examine the induction of programmed cell death in a human colon carcinoma cell line that possesses two mutated p53 alleles. Ionizing radiation alone, or in combination with the chemotherapeutic drug 5-fluorouracil (5-FU), were used to elicit the apoptotic response. This study will focus on whether these treatments can induce a significant apoptotic response in cells that have mutated p53 ...
The DNA double-strand break (DSB) damage responseinduced by high energy charged particles on lung fibroblast cells embedded in a 3-dimensional (3-D) collagen tissue equivalents was investigated using antibodies to the DNA damage response proteins gamma-histone 2AX (#gamma#-H2AX) and phosphorylated DNA-PKcs (p-DNA-PKcs). 3-D tissue equivalents were irradiated in positions across the linear distribution of the Bragg curve profiles of 307.7 MeV/nucleon, 556.9 MeV/nucleon, or 967.0 MeV/nucleon "5"6Fe ions at a dose of 0.30 Gy. Patterns of discrete DNA damage streaks across nuclei or saturated nuclear damage were observed, with saturated nuclear damage being more predominant as samples were positioned closer to the physical Bragg peak. Quantification of the DNA damage signal intensities at each distance for each of the examined energies revealed a biological Bragg curve profile with a pattern of DNA damage intensity similar to ...
A hypothesis of microwave-induced circulatory under perfusion was tested in ketamine anesthetized rats whose heart rate, mean arterial pressure, pulse pressure, respiration rate, and body temperatures were monitored continuously. Fifty-eight ventral head and neck exposures in a waveguide consisted of sham-exposure and exposure to continuous wave (CW) and pulsed 1.25 GHz microwaves for 5 min. The 0.5 Hz and 16 Hz pulsemodulated microwaves were delivered at 400 kW peak power. The CW microwaves were 2 and 6.4 W. The average specific absorption rate was 4.75 W/kg per watt transmitted in the brain and 17.15 W/kg per watt transmitted in the neck. Respiration rate and mean arterial pressure were not altered. Changes in heart rate and pulse pressure were observed in rats exposed to higher power but not to the lower average power microwaves. Depression of pulse pressure, an indication of a decrease in stroke volume, and increased or decreased heart rate were noted in ...
The rate of hepatic cytochrome P450 Cypla1 and Cyp1a2 induction was investigated in C57BL male mice during induction with o-aminoazotoluene (OAT), benzo[a]pyrene (BP) and 1,4-dihydroxyanthraquinone (AQ). The Cypla1 mPNA level determined by quantitative RT-competitive PCR increased more than three orders of magnitude during induction with OAT and BP compared with untreated animals and remained unchanged during induction with AQ. The Cypla2 mRNA level was only 8.5, 18.7 and 1.9 times higher during induction with OAT, BP and AQ respectively than in untreated mice. At the same time 7-Ethoxyresorufin-O-deethylase (EROD) and 7-Methoxyresorufin-O-demethylase (MROD) activities of Cypla were also investigated in liver. The increase of Cypla1 mRNA level correlated with the increase of EROD activity. This suggests involvement of the transcriptional mechanism of the inducibility of this enzyme. In the case of Cypla2 there was insignificant increase of its mRNA level but high ...
Between December 2001 and May 2004, a ventilation experiment (VE) was performed in the Mont Terri Underground Research Laboratory (URL) and co-financed by the Commission of the European Communities. The objective was to investigate the desaturation of consolidated clay formations in consequence of the ventilation of underground openings of a repository in such a formation. The results of the geoelectric measurements performed in the second phase of the Mont Terri ventilation test can be summarized as follows: Geoelectric tomography has been found suitable for monitoring ventilation-induced saturation changes in the Opalinus clay. During ventilation with dry air a desaturation down to below 50% could be detected in both desaturation cycles. The desaturated zone extends less than 0.5 m into the rock around the microtunnel. During the second resaturation phase, ventilation with humid air led to quick resaturation at the tunnel surface, while resaturation of the rock ...
Between December 2001 and May 2004, a ventilation experiment (VE) was performed in the Mont Terri Underground Research Laboratory (URL) and co-financed by the Commission of the European Communities. The objective was to investigate the desaturation of consolidated clay formations in consequence of the ventilation of underground openings of a repository in such a formation. The results of the geoelectric measurements performed in the second phase of the Mont Terri ventilation test can be summarized as follows: Geoelectric tomography has been found suitable for monitoring ventilation-induced saturation changes in the Opalinus clay. During ventilation with dry air a desaturation down to below 50% could be detected in both desaturation cycles. The desaturated zone extends less than 0.5 m into the rock around the microtunnel. During the second resaturation phase, ventilation with humid air led to quick resaturation at the tunnel surface, while resaturation of the rock ...
Full text: The general population is daily exposed to chronic, low doses of ionizing radiation (IR) from both natural and artificial sources. The biological consequences of acute, high dose IR exposure can be readily determined; however, the nature and significance of low dose, low dose-rate IR effects are still the subject of debate. Confounding the issue, are the phenomena collectively referred to as the Radiation-induced Bystander Effect (RIBE). The RIBE describes a collection of in vitro observations that suggest the presence of a soluble, transmissible factor(s) released from irradiated cells that can induce a biological response in un-irradiated cells. The induction, nature and magnitude of the RIBE varies between cell culture systems, radiation sources and end-points measured. Efforts to confirm the presence of the RIBE in vivo have been confined to in vivo-like culture systems and limited work with tumour and ...
Mesenchymal stem cells (MSCs) are a potential source of smooth muscle cells (SMCs) for constructing tissue-engineered vascular grafts. However, the details of how specific combinations of vascular microenvironmental factors regulate MSCs are not well understood. Previous studies have suggested that both mechanical stimulation with uniaxial cyclic strain and chemical stimulation with transforming growth factor {beta}1 (TGF-{beta}1) can induce smooth muscle markers in MSCs. In this study, we investigated the combined effects of uniaxial cyclic strain and TGF-{beta}1 stimulation on MSCs. By using a proteomic analysis, we found differential regulation of several proteins and genes, such as the up-regulation of TGF-{beta}1-induced protein ig-h3 (BGH3) protein levels by TGF-{beta}1 and up-regulation of calponin 3 protein level by cyclic strain. At the gene expression level, BGH3 was induced by TGF-{beta}1, but calponin 3 was not ...
Objectives: We have previously shown that chronic exposure to ambient fine particulate matter (less than 2.5 ?m in aerodynamic diameter, PM(2.5)) pollution in conjunction with high-fat diet induces insulin resistance through alterations in inflammatory pathways. In this study we evaluated the effects of PM(2.5) exposure over a substantive duration of a rodent's lifespan and focused on the impact of long-term exposure on adipose structure and function.Methods and Results: C57BL/6 mice were exposed to PM(2.5) or filtered air (FA) (6 hours/day, 5 days/week) for duration of 10 months in Columbus, OH. At the end of the exposure, PM(2.5)-exposed mice demonstrated insulin resistance (IR) and a decrease in glucose tolerance compared with the FA-exposed group. Although there were no significant differences in circulating cytokines between PM(2.5)- and FA-exposed groups, circulating adiponectin and leptin were significantly decreased in PM(2.5)-exposed group. PM(2.5) ...
PNAS-4, a novel pro-apoptotic gene activated during the early response to DNA damage, can inhibit proliferation via apoptosis when overexpressed in some tumor cells. Recent studies have indicated that honokiol can induce apoptosis, inhibit angiogenesis, and suppress tumor growth. In the present study, we investigated whether mouse PNAS-4 (mPNAS-4) could augment the apoptosis of tumor cells induced by honokiol in vitro, and whether the antiangiogenic activity of honokiol and induction of apoptosis by mPNAS-4 could work cooperatively to improve the antitumor efficacy in vivo. In vitro, mPNAS-4 inhibited proliferation of murine colorectal carcinoma CT26 and Lewis lung carcinoma LL2 cells through induction of apoptosis, and significantly augmented the apoptosis of CT26 and LL2 cells induced by honokiol. Compared with treatment with mPNAS-4 or honokiol alone, in vivo systemic administration of an expression ...
The authors have investigated insulin receptor phosphorylation in differentiated cultured BC3H-1 myocytes. As for other insulin-responsive cell systems in partially purified wheat germ agglutinin receptor preparations, insulin stimulates the phosphorylation of its own receptor (95K ..beta..-subunits) in a dose dependent manner (0-400 nM), as identified by immunoprecipitation with antiinsulin receptor antibodies and SDS-PAGE. In the same preparations they show that 12-0-tetradecanyl phorbol acetate (TPA), which in many respect ..beta..-subunits in the same dose dependent manner (0-5 ..mu..M). In addition, antiinsulin receptor antibodies (B-10) also induced phosphorylation of mimics insulin action, also induced phosphorylation of the insulin receptor and HPLC tryptic maps of the /sup 32/P-labeled ..beta..-subunit were identical to those for insulin-induced receptor phosphorylation. However, while insulin ...
Influenza virus infection during pregnancy has been implicated as one of cause of premature delivery, abortion and stillbirth. We have reported that cultured human fetal membrane chorion cells undergoing apoptosis by influenza virus infection secrete unidentified heat-stable monocyte differentiation-inducing (MDI) factors. In this study, cellular, biological and immunochemical characteristics of MDI factors were investigated using human monocytic leukemia THP-1 cells by nitroblue tetrazolium reduction and cell adhesion assays. The treatment of THP-1 cells with culture supernatants from the influenza virus-infected chorion cells induced the nitroblue tetrazolium reduction ability, which was inhibited by the addition of superoxide dismutase and diphenyleneiodonium chloride, an inhibitor for reduced nicotinamide adenine dinucleotide phosphate oxidase. The phenomenon was also observed in human peripheral blood monocytes and histiocytic leukemia ...
beta-Bungarotoxin (beta-Bgt), a presynaptic phospholipase A(2) (PLA(2)) neurotoxin isolated from the venom of Bungarus multicinctus, consists of A chain and B chain. The goal of the present study is to explore the functional contribution of the two subunits to the toxicity of beta-Bgt. beta-Bgt was found to induce apoptotic death of SK-N-SH cells via elevating intracellular Ca(2+) and intracellular ROS production. Moreover, an activation of p38 MAPK was associated with the cytotoxicity of beta-Bgt. SB202190 (p38 MAPK inhibitor), N-acetylcysteine (antioxidant reagent), 1,2-bis(2-aminophenoxy)ethane-N,N,N,N-tetraacetic acid (BAPTA) (Ca(2+) chelator) and the inhibitors of Ca(2+) release from intracellular depots (ruthenium red and 2-aminoethoxydiphenyl borate) effectively attenuated the cytotoxicity of beta-Bgt. In sharp contrast to the inability of A chain, B chain was able to induce cytotoxic effects on SK-N-SH cells as beta-Bgt did. Abolishment ...
This chapter provides an overview of the problem of response to a nuclear weapon accident, the fundamentals of response to an accident, and a summary of the NARP Manual. The manual provides a summary of procedural guidance, technical information, and DoD responsibilities, to assist DoD forces in preparing a response to a nuclear weapon accident.
A comparison of the concentration-response effects of inhaled ozone (O/sub 3/) in different species of laboratory animals was made in order to better understand the influence of the choice of species in inhalation studies of this gas. The effect of 4-hour exposure to ozone (O/sub 3/) at concentrations of 0.0, 0.2, 0.5, 1.0, and 2.0 ppm was determined in rabbits, guinea pigs, rats, hamsters and mice. Lavage fluid protein (LFP) accumulation 18 hr after exposure was used as the indicator of O/sub 3/-induced pulmonary edema. All species had similar basal levels of LFP (250-350 ug/ml) when a volume of saline which approximated the total lung capacity was used for lavage of the collapsed lungs. Exponential dose-response curves were seen in all species except guinea pigs, which showed significant increases in LFP at low O/sub 3/ concentrations (0.2 ppm) and a leveling off of response at the higher O/sub 3/ ...
Olfactory tract has been demonstrated to be an important portal for inhaled solid nanoparticle transportation into the central nervous system (CNS). We have previously demonstrated that intranasally instilled Fe_2O_3 nanoparticles could transport into the CNS via olfactory pathway. In this study, we investigated the neurotoxicity and size effect of repeatedly low-dose (130 #mu#g) intranasal exposure of nano- and submicron-sized Fe_2O_3 particles (21 nm and 280 nm) to mice. The biomarkers of oxidative stress, activity of nitric oxide synthases and release of monoamine neurotransmitter in the brain were studied. Our results showed that significant oxidative stress was induced by the two sizes of Fe_2O_3 particles. The activities of GSH-Px, Cu,Zn-SOD, and cNOS significantly elevated and the total GSH and GSH/GSSG ratio significantly decreased in the olfactory bulb and hippocampus after the nano- and submicron-sized Fe_2O_3 particle treatment (p < 0.05). The ...
There is a lot of interest in the studies that would help to understand whether there is a casual association between cancer and various types of molecular or cytogenetic damage detected in human cells. One major oncogenesis process is activation of proto-oncogenes by point mutations or chromosomal translocation. There are substantial evidence that indicates that the loss of heterozygosity of certain chromosomes is involved in human cancerogenesis. Our study aimed to elicit the possible association between cancer and DNA and cytogenetic abnormalities induced in lymphocytes of people bearing various categories of skin cancer cells. Fresh blood was collected by venipuncture from 25 individuals (including nine prior to cancer treatment). All patients were nonsmoking males, however 42.3 % of them were former smokers. Blood samples were divided into two parts and in the first part of samples cytogenetic studies were performed immediately, while from the second part ...
The quasi-static normal indentation of sandwich panels with quasi-isotropic laminated composite skins and honeycomb or foam cores, by spherical indentors, has been investigated using experiments and finite element analysis. The experimental program emphasized the effects of indentor size on the resulting load indentation responses, failure mechanisms in the skin and the core, and the measurement of contact areas between indentor and the target. The sandwich panels were indented up to the initiation of skin fracture and the resulting contact data was used to characterize contact power laws. A non-linear finite element model was developed based on the experimental observations to systematically explore the indentation behavior of diverse sandwich configurations and to investigate the contact pressure distributions. The finite element model was used as an experimental tool in the development of a simple non-dimensional semi-empirical model that was based on the ...
In areas where radiation dose monitoring has not been performed, it is essential to use material available in the environment be able to rapidly assess doses to individuals for immediate emergency medical care or for general estimation of the radiological consequences. It was shown that certain types of telephone cards containing microchips have the potential to be used as individual radiation dosimeters in emergency situations to detect doses over 250 mGy by luminescence measurements. In order to understand the dosimetric properties of chip cards, the components obtained from INFINIEON Company at various stages of production were used for luminescence measurements. It is found that the protecting layer used above the chips so called 'globe top' is the main source of radiation induced signal in chip cards. The globe top produced by INFINIEON at that stage is found to contain SiO2 and Epoxy. In order to improve the dosimetric properties of the chip cards, the raw ...
We have studied the correlation between the chemical state and the oxygen-sensing properties of an iron oxide thin film using a setup that allows simultaneous sensor resistance measurements and X-ray photoelectron spectroscopy (XPS) data acquisition. The gas exposures were performed at the highest operating pressure of the XPS spectrometer at a controlled sample temperature which allows direct comparison between the sensor response and the chemical state of the surface. The iron oxide film was modified by a sequence of argon ion sputtering steps and the induced changes in the chemical state, resistance, and sensitivity to oxygen were investigated. The sputtering was found to reduce the iron from the Fe"3"+ to the Fe"2"+ state and to decrease the sensor resistance. The measured sensitivity to oxygen first increased by a factor of two but then collapsed to its original level. The mechanism for oxygen sensing was found to be filling of the oxygen ...
A series of OSL properties of fragments from split feldspar grains have been investigated. These are (1) the response to a radiation dose, (2) the recycling of corrected induced luminescence (L{sub i}/T{sub i}), (3) the corrected natural luminescence (L{sub N}/T{sub N}), (4) the corrected thermal transfer luminescence (termed herein L{sub tt}/T{sub tt}) and, (5) the rate of anomalous fading ('g'). It was found that the parameters of different parts of the same grain are the same. The relative uncertainty, at the 2 sigma level, at which we can claim that the measured parameters are correlated, is generally less than 5% but is ca 40% for the anomalous fading rate due to measurement uncertainty. For young partially bleached sediments, the result is that one could use one fragment to evaluate the equivalent dose and another to assess the contribution of thermal transfer resulting from preheating the natural luminescence.
High salinity is one of the main factors limiting cotton growth and productivity. The genes that regulate salt stress in TM-1 upland cotton were monitored using microarray and real-time PCR (RT-PCR) with samples taken from roots. Microarray analysis showed that 1503 probe sets were up-regulated and 1490 probe sets were down-regulated in plants exposed for 3h to 100mM NaCl, and RT-PCR analysis validated 42 relevant/related genes. The distribution of enriched gene ontology terms showed such important processes as the response to water stress and pathways of hormone metabolism and signal transduction were induced by the NaCl treatment. Some key regulatory gene families involved in abiotic and biotic sources of stress such as WRKY, ERF, and JAZ were differentially expressed. Our transcriptome analysis might provide some useful insights into salt-mediated signal transduction pathways in cotton and offer a number of candidate genes as potential ...
Metastable austenitic steels show excellent mechanical properties, such as high strength combined with excellent ductility and toughness due to martensitic transformation under mechanical loading (transformation induced plasticity effect). A good energy consumption, and, in the case of high-alloyed metastable austenitic steels, a high corrosion resistance, increase the potential of these materials for diverse applications, also in regard of safety requirements. Up to now, numerous wrought alloys were investigated concerning mechanical behaviour, TRIP-effect, martensitic transformation behaviour and modelling of transformation kinetics or stress-strain behaviour. New high alloyed cast CrMnNi-steels, developed at Technical University Bergakademie Freiberg, provide the chance to reduce processing steps, production time and costs. In order to understand the influence of temperature on the martensitic phase transformation behaviour and therefore on mechanical properties ...
During rolling contact fatigue of the inner rings of ball bearings three stages of material response can be distinguished, in terms of the volume that is plastically deformed upon overrolling. After a first stage of material strengthening during which a decrease occurs for the volume that is deformed plastically, an effectively stationary, second stage is entered which is eventually succeeded by a third stage exhibiting a pronounced increase of the volume that is deformed plastically upon overrolling, which leads to failure. It is suggested that carbon diffusion induced by local temperature peaks occurring at the moment of overrolling is the key mechanism leading to fatigue damage. The amount of decomposed retained austenite is a useful, practical parameter to assess fatigue life. It is shown that published ideas about the role of certain components of residual stress in enhancing fatigue life are not correct and that the so-called ...
Escherichia coli spheroplast protein y (EcSpy) is a small periplasmic protein that is homologous with CpxP, an inhibitor of the extracytoplasmic stress response. Stress conditions such as spheroplast formation induce the expression of Spy via the Cpx or the Bae two-component systems in E. coli, though the function of Spy is unknown. Here, we report the crystal structure of EcSpy, which reveals a long kinked hairpin-like structure of four ?-helices that form an antiparallel dimer. The dimer contains a curved oval shape with a highly positively charged concave surface that may function as a ligand binding site. Sequence analysis reveals that Spy is highly conserved over the Enterobacteriaceae family. Notably, three conserved regions that contain identical residues and two LTxxQ motifs are placed at the horizontal end of the dimer structure, stabilizing the overall fold. CpxP also contains the conserved sequence motifs and has a predicted ...
Prairie (Microtus ochrogaster) and meadow voles (M. pennsylvanicus) are closely related species that differ in life strategy and social behaviors, and thus provide an excellent comparative model for the study of neuronal and hormonal mechanisms underlying behavior. In the present study using the elevated plus maze (EPM) test, we found that male prairie voles entered the open arms of the EPM more and remained there longer, and showed a higher level of overall locomotor activity than did male meadow voles. In addition, two weeks of social isolation induced an increase in open arm entries in prairie, but not meadow, voles. Prairie voles also had a higher level of circulating corticosterone compared to meadow voles, and the EPM test increased circulating corticosterone in prairie voles. Finally, social isolation coupled with the EPM test influenced Fos-immunoreactive expression in several brain areas, including the medial preoptic area, ventromedial hypothalamus, ...
Current bioartificial extra-corporeal systems are bioreactors where cells are separated from the surrounding media by porous polymeric membranes. The present work focuses on the design of membranes that allow the differential diffusion of plasma metabolites and proteins such as immunoglobulin (IgG). This design will improve catabolites removal and reduce possible immune response and virus infection. We demonstrate the feasibility to synthesize the hydrogels confined to the macroporous structure of membranes by radiation-induced in situ polymerization. The hollow-fiber membranes were soaked in aqueous monomeric solution, rinsed and irradiated while submerged in oil. This procedure confined the hydrogel to the void internal volume of the pores of the membrane. Hydrogels of polyacrylamide and polyHEMA were synthesized this way by irradiation at 10 kGy. Hydraulic permeability and diffusion of glucose, albumin and IgG were measured in these ...
Aminocyclopropane 1-carboxylic acid (ACC) synthase, a pyridoxal phosphate utilizing enzyme, catalyzes the conversion of S-adenosylmethionine to ACC, the rate limiting step in the biosynthesis of the plant hormone, ethylene. Ethylene, besides being involved in normal plant growth processes, is also produced in response to stress, e.g. wounding, pathogen infection, etc. The authors report the partial purification (400 fold) of ACC synthase from wounded pink tomato pericarp by classical techniques including ammonium sulfate precipitation, ion exchange and phenyl sepharose chromatography. Further purification results in a decrease in specific activity apparently due to the instability of the enzyme and the low levels present in plant tissue. Radiolabeling of a pyridoxal phosphate-utilizing protein in the ACC synthase enriched fraction was achieved. Evidence that this radiolabeled protein is ACC synthase will be presented. Amino acid sequence determination of putative ...
Conditions for radiation induced grafting with butyl acrylate dispersed in water emulsion onto chrome-tanned pig skins have been worked out for #gamma#-rays and electron beam irradiations. The highest yield of grafting was observed at monomer concentration approximately 25% (w/w), dose equal to 25 kGy and dose rate not exceeding 10 MGy/h. At these conditions the yield of grafting attained a value approximately 25% and content of homopolymer in the leather amounted to 6%. The efficiency of monomer to polymer conversion decreases when the concentration of monomer in emulsion and dose rate increases. Yield of homopolymer is independent of the dose rate. An explanation of the observed relations has been proposed. The physical and used properties of grafted leathers were tested. Radiation processed leathers were found superior to samples finished by traditional methods. One has to point to better tolerance against chemical cleaning and reduced water take-up without loss ...
Estrogen metabolism is suggested to play an important role in estrogen-induced breast carcinogenesis. Epidemiologic studies suggest that diets rich in phytoestrogens are associated with a reduced risk of breast cancer. Phytoestrogens are biologically active plant compounds that structurally mimic 17b-estradiol (E2). We hypothesize that phytoestrogens, may provide protection against breast carcinogenesis by altering the expression of estrogen-metabolizing enzymes cytochrome P450 1A1 (Cyp1A1) and 1B1 (Cyp1B1). Cyp1A1 and Cyp1B1 are responsible for the metabolism of E2 to generate 2-hydroxyestradiol (2-OHE2) and 4-hydroxyestradiol (4-OHE2), respectively. Studies suggest that 2-OHE2 and 2-methoxyestradiol may protect against breast carcinogenesis, while 4-OHE2 is carcinogenic in rodent models....
A method to control charge transfer reaction in DNA using hybrid nanometer-sized TiO{sub 2} nanoparticles was developed. In this system extended charge separation reflects the sequence of DNA and was measured using metallic silver deposition or by photocurrent response. Light-induced extended charge separation in these systems was found to be dependent on the DNA-bridge length and sequence. The yield of photocatalytic deposition of silver was studied in systems having GG accepting sites imbedded in AT runs at varying distances from the TiO{sub 2} nanoparticle surface. Weak distance dependence of charge separation indicative of a hole hopping through mediating adenine (A) sites was found. The quantum yield of silver deposition in the system having a GG accepting site placed 8.5 {angstrom} from the nanoparticle surface was found to be {Phi} = 0.70 (70%) and {Phi} = 0.56 (56%) for (A){sub n} and (AT){sub n/2} bridge, respectively. Hole injection ...
Sputter-deposited tantalum (Ta) and reactively sputter-deposited Ta-nitride films were studied with respect to the passivation capability against copper (Cu) oxidation in thermal O{sub 2} ambient. A 200 {angstrom} Ta or Ta-nitride film was sputter-deposited on a 2,000 {angstrom} Cu film using a Ta target in an Ar/N{sub 2} gas mixture. With Ta passivation, Cu was not oxidized at temperatures up to 400 C, which can be further improved by using passivation of an amorphous Ta-nitride film deposited in an appropriate condition. The absence of long-range defects in the Ta-nitride film was presumably responsible for this improvement. However, sputtering-induced surface damage by excess N{sub 2} in the sputter gas mixture may reduce the passivation capability of Ta-nitride films. When the passivated Cu was oxidized, the Cu oxides always resided in the top surface region. That is, in the oxidation process, Cu diffused through the defects of the ...
A series of experimental measurements of ozone concentration produced by irradiation of noble gas (He, Ne, and Ar)-O_2 and noble gas-O_2- SF_6 mixtures with energetic (MeV) helium and lithium ions are reported. Continuous irradiations at dose rates of 10"1"5-10"1"7 eV cm"-"3 S"-"1 for a few hundred milliseconds were used. The resulting ozone concentration was found to be nonlinear with dose rate for a given irradiation time. This nonlinearity was effectively reduced by an increase in noble gas pressure. Few mole percent addition of SF_6 generally resulted in an increase in the ozone concentration. This increase was highest for lower noble gas pressures and longer irradiation times. Further SF_6 addition, however, caused a reduction in the ozone concentration. Results are explained by considering the relevant reactions responsible for ozone production and loss.
Investigations into sexual differentiation and pheromone response in the fission yeast Schizosaccharomyces pombe are complicated by the need to first starve the cells of nitrogen. Most mating-related experiments are therefore performed on non-dividing cells. Here we overcome this problem by using two mutants that bypass the nutritional requirements and respond to the M-factor mating pheromone in rich medium. The first mutant lacks the cyr1 gene which encodes adenylate cyclase and these cells contain no measurable amounts of cAMP. When M-factor is added to a growing h+ cyr1- strain it causes a transient G1 arrest of cell division, transcription of mat1-Pm, and elongation of the cells to form shmoos. The second mutant contains the temperature-sensitive pat1-114 allele. At 30 degrees C this mutant was previously shown not only to bypass the nutritional signal but also to stop growing in a state derepressed for pheromone-controlled functions. We now report that an h+ ...
Parkinson's disease (PD) is the most common neurodegenerative movement disorder. Mutations in PTEN-induced kinase 1 (PINK1) are a frequent cause of recessive PD. Autophagy, a pathway for clearance of protein aggregates or impaired organelles, is a newly identified mechanism for PD development. However, it is still unclear what molecules regulate autophagy in PINK1-silenced cells. Here we report that autophagosome formation is promoted in the early phase in response to PINK1 gene silencing by lentivirus transfer vectors expressed in mouse striatum. Reduced PP2A activity and increased phosphorylation of PP2A at Y307 (inactive form of PP2A) were observed in PINK1-knockdown dopaminergic cells and striatum tissues. Treatment with C2-ceramide (an agonist of PP2A) reduced autophagy levels in PINK...
Studies were undertaken to examine the effects of animal age on the anticarcinogenic properties of antioxidants. Female hairless mice, 2.5, 4.5 and 9.5 months of age, were subjected to daily irradiation from Westinghouse BZS-WLG lamps for 19 weeks. Experimental groups of animals were maintained on a commercial rodent meal supplemented with a 2% (w/w) antioxidant mixture. Control groups received only the meal. Tumour latency, expressed as median time to tumor development, was significantly greater for all age groups receiving antioxidants than for their similarly aged controls. However, the response to antioxidants appeared to decrease with age and the antioxidant effect was significantly less in the 9.5 month-old group than in the 2.5 month-old group. Likewise, the two youngest groups receiving antioxidants demonstrated a significantly fewer number of tumors per animal. It is concluded that animal age influences the degree of photoprotection provided by ...
Abstract Sam68 (Src-associated protein in mitosis 68-kDa) is a multifunctional protein, known to govern cellular signal transduction, transcription, RNA metabolism, proliferation, apoptosis, and HIV-1 replication. Although intrinsic mechanisms that modulate Sam68 function are beginning to emerge, the regulatory events contributing to its expression remain elusive. We previously reported that heat shock protein-22 (Hsp22) antagonizes Sam68 function in rev-response element (RRE)-mediated gene expression. We now demonstrate that Sam68 levels correlate inversely with Hsp22 in a variety of cells, including U87, Jurkat, 293T, and U-937. In U87 glioblastoma cells, which contained high levels of Hsp22 than other cell lines tested, Hsp22 knockdown dramatically increased both Sam68 mRNA and protein,...
Neutron irradiation embrittlement of reactor pressure vessel (RPV) steels is one of the critical issues on aging management for long term operation of nuclear power plants. Mechanistic understanding of embrittlement is a key to accurate prediction of embrittlement, especially after long term operation where the mechanical test data are sparse. Since matrix hardening is the source of the embrittlement, we focus on matrix hardening of A533B bainitic pressure vessel steel. Bainitic matrix is composed of lath structure made by ferrite and carbides, therefore it is important to understand how this structure affects hardening behavior, and to understand irradiation response of each phase. As the typical dimension of lath structure of A533B is about one micron, nanoindentation technique is suitable for the estimation of hardening of each phase. MV ion accelerators were used for controlled irradiation because MeV ion irradiation can produce defects to the depth greater ...
Measuring gene expression using microarrays is relevant to many areas of biology and medicine, such as follow up of developmental stages and diseases onset, and treatment study. Since there can be tens of thousands of distinct probes on an array, each micro array experiment can accomplish the equivalent number of genetic tests in parallel. Arrays have therefore dramatically accelerated many types of investigations. For example, microarrays can be used to identify stress response genes by comparing gene expression in challenged versus normal cells. In the Molecular and Cellular Biology lab (MCB), the micro array experiments are performed within the Genomic Platform, fully equipped to analyse either the behaviour of bacteria during long space flight, the effect of low dose ionising radiation on the developing organism in mice, or the human individual radiation sensitivity. For the low dose effect, two main stages of development are of interest; 1) the gastrula stage ...
In this paper, we present the results of Plasma-Enhanced Chemical Vapor Deposition gate-oxide (SiO_2) integrity on ELC (excimer-laser-crystallized), MILC (metal-induced lateral-crystallized) and SPC (solid-phase-crystallized) polysilicon films. We observed that gate oxide strength of poly-Si TFT strongly depends on the crystallization method for the active silicon layer. In the case of ELC films, asperities on the silicon surface reduce the SiO_2 breakdown field significantly. The metallic contaminants in MILC films are responsible for a deleterious impact on gate oxide integrity. Among the three cases, the SiO_2 breakdown field was the highest for the SPC silicon films. The breakdown fields at the 50 % failure points in Weibull plots for the ELC, MILC and SPC cases were 5.1 MV/cm, 6.2 MV/cm, and 8.1 MV/cm, respectively. We conclude that the roughness and metallic contamination of the poly-Si films are the main factors that cause enhanced ...
An experimental and computational study was undertaken to estimate the effects of pipe rupture and induced pipe whip impact on surround structures considered either as rigid or deformative such as concrete slabs. This program included sixteen tests using 3 inch schedule 80 (or 10) pipes made of carbon steel similar to A106 grade B. The study consisted of tests on rigid target and on concrete slab. The investigation of whip phase and impact phase was done separately for each test. For pipe impact on rigid targets, the impact forces are found to be directly related to the crush strength of the pipe and the general pipe deformation following the impact. For pipe impact on concrete slabs, the response of the target to the pipe impact needs to take into account the local effect such as penetration and localized damage on the slab. The test matrix covered a broad range of geometric parameters. It provides a significant data base for studying pipe ...
The accumulation of osmolytes in leaf tissues and the abscisic acid-induced stomatal closure are well-recognized mechanisms associated with drought tolerance in crop plants. We determine the response in terms of osmotic potential and the contents of leaf proline, glycine betaine and soluble sugar at booting and grain filling stages of four wheat (Triticum aestivum L.) cultivars to drought and exogenously applied abscisic acid (ABA) in a pot study. Leaf sample were collected 3, 6 and 9 days after drought induction and at 48 and 72 h of re-watering (recovery). Marked decreases in osmotic potential associated with the accumulation of proline, glycine betaine and soluble sugars occurred under conditions of drought stress Accession 011320 was most sensitive to drought and showed the largest decrease in osmotic potential and least accumulation of proline, sugar and glycine betaine The inhibitory effects of drought stress were ameliorated by exogenous ...
The dynamical factors controlling the mean state and variability of the east Pacific intertropical convergence zone (ITCZ) and the associated cross-equatorial boundary layer flow are investigated using observations from the East Pacific Investigation of Climate (EPIC2001) project. The tropical east Pacific exhibits a southerly boundary layer flow that terminates in the ITCZ. This flow is induced by the strong meridional sea surface temperature (SST) gradient in the region. Away from the equator and from deep convection, it is reasonably well described on a day-to-day basis by an extended Ekman balance model. Variability in the strength and northward extent of this flow is caused by variations in free-tropospheric pressure gradients that either reinforce or oppose the pressure gradient associated with the SST gradient. These free-tropospheric gradients are caused by easterly waves, tropical cyclones, and the Madden Julian oscillation.Convergence in the boundary ...
Iron undergoes a polymorphic phase transformation from alpha phase (bcc) to the epsilon phase (hcp) when compressed to stresses exceeding 13 CPa. Bccause the epsilon phase is denser than the alpha phase, a single shock wave is unstable and breaks up into an elastic wave, a plastic wave, and a phase transition wave. Examination of this structured wave coupled with various phase transformation models has been used to indirectly examine the transition kinetics. Recently, multimillion atom simulations (molecular dynamics) have been used to examine the shock-induced transition in single crystal iron illustrating an orientation dependence of the transition stress, mechanisms, and kinetics. The objective of the current work was to perform plate impact experiments to examine the shock-response of polycrystalline and single crystal iron with nanosecond resolution for impact stresses spanning the {alpha} - {epsilon} transition. The current data reveal an ...
The development of modern techniques for the cooling and the manipulation of atoms in recent years, and the possibility to create Bose-Einstein condensates and degenerate Fermi gases and to load them into regular optical lattices or disordered optical potentials, has evoked new interest for the disorder-induced localization of ultra-cold atoms. This work studies the transport properties of matter waves in disordered optical potentials, which are also known as speckle potentials. The effect of correlated disorder on localization is first studied numerically in the framework of the Anderson model. The relevant transport parameters in the configuration average over many different realizations of the speckle potential are then determined analytically, using self-consistent diagrammatic perturbation techniques. This allows to make predictions for a possible experimental observation of coherent transport phenomena for cold atoms in speckle potentials. Of particular ...
Changes in contents of the two kinds of neuropeptides have been measured in the brains of postnatal G57BL/6J strain mice that received accumulative doses of 0, 0.05, 0.10 or 0.30 Gy respectively in utero from tritium #beta#-irradiation during the mother mice's pregnancy from the 12.5th day of gestation to the day of delivery. Dose response relationship for alteration in somatostatin content due to exposure to 0.10 Gy or above was observed, and it was also noted that 0.30 Gy could cause decrease in arginine vasopressin in hypothalamus. These results were consistent with findings in research on brain development and reflex behavior in the literature. 0.10 Gy exposure may represent a threshold for exposure to tritiated water within the range from day 12.5 of gestation to the day of delivery using change in content of somatostatin in hypophysis as a parameter.
In response to a heat shock, the yeast Saccharomyces cerevisiae undergoes a large increase in its resistance to heat and, by the induction of its recombinational DNA repair capacity, a corresponding increase in resistance to radiation. Yeast which lack mitochondrial DNA, mitochondria-controlled protein synthetic apparatus, aerobic respiration, and electron transport (rho/sup 0/ strain) were used to assess the role of O/sub 2/, mitochondria, and oxidative processes controlled by mitochondria in the induction of these resistances. We have found that rho/sup 0/ yeast grown and heat shocked in either the presence or absence of O/sub 2/ are capable of developing both radiation and heat resistance. We conclude that neither the stress signal nor its cellular consequences of induced heat and radiation resistance are directly dependent on O/sub 2/, mitochondrial DNA, or mitochondria-controlled protein synthetic or oxidative processes.
Abstract. Objective: Lapatinib (Tykerb, GW572016), a potent inhibitor of the catalytic activities of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) (ErbB2), inhibits population growth of selected EGFR and HER2 overexpressing cell lines. Previous studies with a small number of cell lines suggest a correlation between overexpression of EGFR and/or HER2 and sensitivity to growth inhibition by lapatinib; however, the precise determinants of lapatinib selectivity for tumour and/or other cells remain unclear. Materials and methods: To clarify the determinants of its selectivity in cultured cells, lapatinib-induced cell population growth inhibition and relative EGFR and HER2 protein expression were quantified in 61 different human tumour cell lines fro...
The possibility of improving the cold formability of wrought magnesium alloys is considered in light of their good hot forming characteristics. Magnesium alloy AZ31B sheet is selected as a model system. Parameters affecting formability, such as strain hardening rate, strain rate sensitivity, and the degree of anisotropy are examined systematically by conducting tensile tests over a range of temperatures (room temperature to 250 C) and strain rates (1 x 10{sup -5} to 0.1 s{sup -1}). The plastic anisotropy and deformation texture evolution are examined in samples aligned with the sheet rolling and transverse directions. Polycrystal plasticity simulations using a viscoplastic self-consistent (VPSC) formulation are used to model the observed anisotropy and texture evolution. The adjustable parameters in the model are the relative critical resolved shear stresses of the dislocation mechanisms known to operate within magnesium. The experimental results suggest that an increased strain rate ...
The thermomechanical behaviour of clayey soils was examined in a laboratory study because of their importance in some engineering applications such as hydrocarbon extraction from oil-bearing sands and radioactive waste disposal. The slightest temperature variations have been known to have an impact on the mechanical behaviour of clayey soils. In this study, tests were conducted on reconstituted and natural clayey soils using triaxial cells modified to control temperatures. Changes of temperature and stress state were not applied simultaneously. Instead, the tests were divided into two separate sections aimed at studying the thermal and mechanical behaviour of clays. The thermal behaviour tests examined the deformations induced by drainage temperature changes as well as pore-pressure generation and consolidation phenomena. The mechanical behaviour tests, focused on the influence of temperature and temperature history on compressibility, deformability and shear ...
Although the p53 tumor suppressor is relatively well characterized, much less is known about the functions of other members of the p53 family, p73 and p63. Here, we present evidence that in specific pathological conditions caused by exposure of normal cells to bile acids in acidic conditions, p73 protein plays the predominant role in the DNA damage response. These pathological conditions frequently occur during gastric reflux in the human esophagus and are associated with progression to esophageal adenocarcinoma. We found that despite strong DNA damage induced by bile acid exposure, only p73 (but not p53 and p63) is selectively activated in a c-Abl kinase-dependent manner. The activated p73 protein induces DNA damage repair. Using a human DNA repair PCR array, we identified multiple DNA repair genes affected by p73. Two glycosylases involved in base excision repair, SMUG1 and MUTYH, were characterized and found to be ...
In the present study, the immunomodulatory effect of {beta}-endorphin ({beta}-E) and shorter pro-opiomelancortin (POMC) fragments was evaluated by assessing their influence on respiratory burst in human polymorphonuclear leukocytes (PMN). The effect of the peptides on phorbol myristate acetate (PMA)-stimulated production of reactive oxygen metabolites was measured in a lucigenin-enhanced chemiluminescence (CL) assay. Both POMC peptides with opiate-like activity and their non-opioid derivatives were tested. With the exception of {alpha}-E, PMA-stimulated respiratory burst was suppressed by all POMC fragments tested. A U-shaped dose-response relation was observed. Doses lower than 10{sup {minus}17}M and higher than 10{sup {minus}8}M were without effect. {beta}-E and dT{beta}E both suppressed PMA-induced oxidative burst in human PMN at physiological concentrations. {gamma}-E and dT{gamma}E proved to be less potent inhibitors, reaching maximal ...
Transients induced in nuclear power plants from many sources result in one or more fluid conditions changing with time. Fluid conditions of pressure, inlet temperature, inlet flow, or even system power many change separately or in conjunction with each other. The result of the condition change may be one which induces departure from nucleate boiling. An experimental investigation of transient which were intended to achieve Critical Heat Flux was performed at the Heat Transfer Research Facility of Columbia University for Siemens Nuclear Power Corporation. The transients were set up to include broad ranges of flow and pressure conditions near the operating range of pressurized water reactors. Transient events were dominated by varying single conditions and measuring the response of the system and of the rod thermocouples. Because of coupling effects within the test loop, secondary conditions would also vary. In order to ...
Positron annihilation experiments on Fe-Cu model dilute alloys of nuclear reactor pressure vessel (RPV) steels have been performed after neutron irradiation in JMTR. Nanovoids whose inner surfaces were covered by Cu atoms were clearly observed. The nanovoids transformed to ultrafine Cu precipitates by dissociating their vacancies after annealing at around 400degC. The nanovoids and the ultrafine Cu precipitates are strongly suggested to be responsible for irradiation-induced embrittlement of RPV steels. Effects of Ni, Mn and P addition on the nanovoid and Cu precipitate formations were also studied. The nanovoid formation was enhanced by Ni and P, but suppressed by Mn. The Cu precipitates after annealing around 400degC were almost free from these doping elements and hence were pure Cu in the chemical composition. Furthermore the Fermi surface of the 'embedded' Cu precipitates with a body centered cubic crystal structure was ...
Embryos of chicken (Gallus domesticus), domestic duck (Anas platyrhynchos), and common eider duck (Somateria mollissima) were exposed in ovo to PCBs and to polycyclic aromatic hydrocarbons. Two coplanar PCBs, 3,3{prime},4,4{prime}-tetrachlorobiphenyl (PCB {number_sign}77) and 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB {number_sign}126), were considerably more lethal and potent as inducers of 7-ethoxyresorufin O-deethylase (EROD) in chicken embryos (Gallus domesticus) than in embryos of the other two species. In chicken embryos, these compounds caused edema and eye and beak deformities. An artificial mixture of 18 PAHs which all have been detected in environmental samples, was slightly more toxic to embryos of the domestic duck and the common eider duck than to chicken embryos. The most potent compound in the mixture was benzo(k)fluoranthene. When chicken embryo livers were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in vitro, EROD was ...
Retroviruses are well known pathogens of mammals, birds and fish. Their potential to induce cancer in chickens was already described almost 100 years ago and murine retroviruses have been a subject of study for 50 years. The first human retroviruses, HTLV and HIV, were discovered more than 30 years ago, surprising researchers and physicians by the profound differences in the diseases they cause. HTLV-1 is able to induce, after decades of infection, lymphomas/leukemia or neuroimmune disorders whereas untreated HIV infection leads almost inevitably to AIDS. The recently described XMRV (xenotropic murine leukemia virus-related virus) appeared to possess many of the features known for HTLV and was regarded by some to be the third human retrovirus. However, recent publications by Knox et al. [1] and Paprotka et al. [2] have shed new light on this gammaretrovirus. Knox and colleagues clearly demonstrate that XMRV is absent in patients belonging to a ...
Cinnabar, a naturally occurring mercuric sulfide (HgS), has long been used in combination with traditional Chinese medicine as a sedative for more than 2000 years. Up to date, its pharmacological and toxicological effects are still unclear, especially in clinical low-dose and long-term use. In this study, we attempted to elucidate the effects of cinnabar on the time course of changes in locomotor activities, pentobarbital-induced sleeping time, motor equilibrium performance and neurobiochemical activities in mice during 3- to 11-week administration at a clinical dose of 10 mg/kg/day. The results showed that cinnabar was significantly absorbed by gastrointestinal (G-I) tract and transported to brain tissues. The spontaneous locomotor activities of male mice but not female mice were preferentially suppressed. Moreover, frequencies of jump and stereotype-1 episodes were progressively decreased after 3-week oral administration in male and female mice. ...
Peroxisome proliferating agents (PPAs) are a structurally diverse group of chemicals that include environmental chemical contaminants such as certain chlorinated herbicides, solvents and plasticizers. PPAs have previously been shown to induce anti-trout laruci acid hydroxylase immunoreactive proteins in bluegill and catfish. In this investigation, induction of lauric acid hydroxylase activity and immunoreactive proteins was confirmed, and the mass spectral analysis of specific hydroxylation products was performed in order to identify possible species-specific differences in fatty acid metabolism. Male bluegill (Lepomis macrochirus) and channel catfish (Ictalurus punctatus) were administered clofibrate or ciprofibrate 48 hr prior to hepatic or trunk kidney (catfish only) microsome preparation. While no significant differences were observed in male catfish, male bluegill had significant decreases in hematocrit and plasma protein indicating hemodilution due to ...
Spontaneous mutation has been discovered and utilized in domestication of narrow-leafed lupin (Lupinus angustifolius L.). As the result of the domestication, lupin has become a dominant grain legume crop in Western Australia. Facing the new challenge of developing herbicide tolerance cultivars, chemical mutagenesis has been used to create new tolerance to herbicide. This paper reports the characterization of two lupin mutants (Tanjil-AZ-33 and Tanjil-AZ-55) that are highly tolerant to metribuzin herbicide. A dose response study over 8 doses revealed that Tanjil-AZ-33 was 6 times more tolerant to metribuzin than the original parental cultivar Tanjil by measure of LD50. This mutant Tanjil-AZ-33 is the most tolerant germplasm in narrow-leafed lupin. Both mutants also maintain the high resistance to the disease anthracnose as cv Tanjil. Seed yield based on small field plots (3.6 m"2) under irrigation was 4.2 t/ha for Tanjil-AZ-33 and 1.9 t/ha for Tanjil when the ...
Paraquat (1,1'-dimethyl-4,4'-bipyridinium) is a widely used herbicide known to induce skin toxicity. This is thought to be due to oxidative stress resulting from the generation of cytotoxic reactive oxygen intermediates (ROI) during paraquat redox cycling. The skin contains a diverse array of antioxidant enzymes which protect against oxidative stress including superoxide dismutase (SOD), catalase, glutathione peroxidase-1 (GPx-1), heme oxygenase-1 (HO-1), metallothionein-2 (MT-2), and glutathione-S-transferases (GST). In the present studies we compared paraquat redox cycling in primary cultures of undifferentiated and differentiated mouse keratinocytes and determined if this was associated with oxidative stress and altered expression of antioxidant enzymes. We found that paraquat readily undergoes redox cycling in both undifferentiated and differentiated keratinocytes, generating superoxide anion and hydrogen peroxide as well as increased protein oxidation which ...
Previous in vitro studies have demonstrated that Ho:YLF laser is capable of inducing physical and chemical changes on dental surfaces treated for caries prevention. The temperature in the pulp chamber was in vitro evaluated to as a function of the power and frequency of the laser irradiation. The purpose of this work is to verify the occurrence of pulp inflammation after Ho:YLF laser irradiation using different parameters in rabbits' teeth. The premolars and molars of ten rabbits (NZB) were divided in two groups according to the irradiation energy values of a Ho:YLF laser prototype operating at 2.065{mu}m wave length, frequency of O,5Hz and pulse length of 250{mu}s. An group A teeth were irradiated with using ten pulses of 334mJ/pulse of a Ho:YLF laser prototype operating at O.5Hz, and group B, with 512mJ/pulse. Animals were killed by transcardiac perfusion and the samples were prepared for histopathological analysis. The in vitro temperature monitoring ...
The insulin signaling pathway, involving protein kinase B (PKB) and mitogen-activated protein kinase (MAPK), mediates the biological response to insulin and several growth factors and cytokines. To investigate the correlation between glucose transporter (Glut) biosynthesis and the insulin signaling pathway activated by novel compounds of Liriope platyphylla (LP9M80-H), alterations in Glut and key protein expression in the insulin signaling pathway were analyzed in the liver and brain of ICR mice treated with LP9M80-H. An in vitro assay showed that the highest level of insulin concentration was observed in the LP9M80-H-treated group, followed by the LP-H, LP-M, LP-E, and LP9M80-C-treated groups. Therefore, LP9M80-H was selected for use in studying the detailed mechanism of the insulin signaling pathway in animal systems. In an in vivo experiment, LP9M80-H induced a significant increase in glucose levels and a decrease of insulin concentration in ...
Sida cordifolia is a plant belonging to the Malvaceae family used in many ayurvedic preparations. This study aimed at assessing the effects of ethanolic extract of Sida cordifolia root on quinolinic acid (QUIN) induced neurotoxicity and to compare its effect with the standard drug deprenyl in rat brain. Rats were divided into six groups: (1) control group (2) QUIN (55 microg/100 g bwt/day) (3) 50% ethanolic plant extract treated group (50 mg/100 g bwt/day) (4) Deprenyl (100 microg/100 g bwt/day) (5) QUIN (55 microg/100 g bwt/day) + 50% ethanolic plant extract treated group (50 mg/100 g bwt/day) (6) QUIN (55 microg/100 g bwt/day) + Deprenyl (100 microg/100 g bwt/day). At the end of the experimental period a status of lipid peroxidation products, protein peroxidation product, activities of the scavenging enzymes and the activities of the inflammatory markers were analyzed. Results revealed that the lipid peroxidation products decreased and the activities of the ...
The linear/supralinear behaviour of the TL dose response in LiF:Mg,Ti (TLD-100) and its dependence on ionisation density is a fairly unique phenomenon which cannot be explained by conventional atomic 'conduction band/valence band' kinetic models. The Track Interaction Model (TIM) provides the microscopic framework which, when coupled with other appropriate physical mechanisms (spatial localisation of traps and recombination centres, competing centres, variations in the capture cross sections with temperature, etc.) can be used to describe all the dominant features of the TL supralinearity of LiF:Mg,Ti and similar TL systems. The unique feature of the TIM applied to alpha particles is that it is an integral approach with only one free parameter, the average charge carrier migration distance in the luminescence recombination stage. Although the TIM provides a comprehensive description of the mechanisms underlying supralinearity in TLD-100, ...
The themal neutron sensitivities of SEI and Toshiba FD-P10-7 radiophotoluminescent silver activated metaphosphate glass dosimeters have been measured and studied theoretically. The graphite thermal neutron column attached to the AEEW reactor NESTOR was utilised as a source of thermal neutrons with minimal fast neutron and gamma-ray contamination. Both the neutron removal and gamma correction measurement techniques were applied and these gave consistent results. It was found that the thermal neutron sensitivity of the Toshiba dosimeters is comparable to the most neutron intensitive thermoluminescent materials available. Because of their larger size and higher silver concentration, however, SEI dosimeters are an order of magnitude more neutron sensitive. The neutron sensitivity of FD-7 glass has not been reported previously, whereas in the case of SEI glass, there exists a modest body of previous work on dosimeters of nominally identical composition. The present results are in reasonable ...
The themal neutron sensitivities of SEI and Toshiba FD-P10-7 radiophotoluminescent silver activated metaphosphate glass dosimeters have been measured and studied theoretically. The graphite thermal neutron column attached to the AEEW reactor NESTOR was utilised as a source of thermal neutrons with minimal fast neutron and gamma-ray contamination. Both the neutron removal and gamma correction measurement techniques were applied and these gave consistent results. It was found that the thermal neutron sensitivity of the Toshiba dosimeters is comparable to the most neutron intensitive thermoluminescent materials available. Because of their larger size and higher silver concentration, however, SEI dosimeters are an order of magnitude more neutron sensitive. The neutron sensitivity of FD-7 glass has not been reported previously, whereas in the case of SEI glass, there exists a modest body of previous work on dosimeters of nominally identical composition. The present results are in reasonable ...
Autophagy is an intracellular recycling route in eukaryotes whereby organelles and cytoplasm are sequestered in vesicles, which are subsequently delivered to the vacuole for breakdown. The process is induced by various nutrient-responsive signaling cascades converging on the Autophagy-Related1 (ATG1)/ATG13 kinase complex. Here, we describe the ATG1/13 complex in Arabidopsis thaliana and show that it is both a regulator and a target of autophagy. Plants missing ATG13 are hypersensitive to nutrient limitations and senesce prematurely similar to mutants lacking other components of the ATG system. Synthesis of the ATG12-ATG5 and ATG8-phosphatidylethanolamine adducts, which are essential for autophagy, still occurs in ATG13-deficient plants, but the biogenesis of ATG8-decorated autophagic bodies does not, indicating that the complex regulates downstream events required for autophagosome enclosure and/or vacuolar delivery. Surprisingly, levels of the ...
A comparison of the concentration-response effects of inhaled ozone (O/sub 3/) and phosgene (COCl/sub 2/) in different species of laboratory animals was made in order to better understand the influence of the choice of species in inhalation toxicity studies. The effect of 4-h exposures to ozone at concentrations of 0.2, 0.5, 1.0, and 2.0 ppm, and to COCl/sub 2/ and 0.1, 0.2, 0.5, and 1.0 ppm was determined in rabbits, guinea pigs, rats, hamsters, and mice. Lavage fluid protein (LFP) accumulation 18-20 h after exposure was used as the indicator of O3- and COCl/sub 2/-induced pulmonary edema. All species had similar basal levels of LFP (250-350 mg/ml) when a volume of saline that approximated the total lung capacity was used to lavage the collapsed lungs. Ozone effects were most marked in guinea pigs, which showed significant effects at 0.2 ppm and above. Mice, hamsters, and rats showed effects at 1.0 ppm O3 and above, while rabbits responded ...
PPARgamma agonists have been proposed to exert more than metabolic benefits, particularly by anti-inflammatory mechanisms. We hypothesized that pioglitazone might modulate inflammatory and vascular responses to lipopolysaccharide (LPS). In a placebo-controlled parallel-group study in 18 healthy male subjects, the E. coli endotoxin model of inflammation (20 IU/kg i. v.) was employed to test the effect of 60 mg pioglitazone over nine days on inflammatory cytokines. Macrovascular function and microvascular blood flow were assessed by brachial artery ultrasound and retinal blood flow parameters, respectively. Pioglitazone increased brachial artery diameter by 5.6% but had no effect on other outcome parameters under resting conditions. LPS increased cytokine levels to peak concentrations of 91.3+/-22.5 ng/ml (IL-6), 261.4+/-60.0 ng/ml (TNFalpha), and 524.5+/-15.3 ng/ml (VCAM-1). The endotoxin caused microvascular vasodilation and increased retinal white blood cell flux, ...
Background: EGFR (epidermal growth factor receptor) and VEGF (vascular endothelial growth factor) inhibitors confer clinical benefit in metastatic colorectal cancer when combined with chemotherapy. An emerging strategy to improve outcomes in rectal cancer is to integrate biologically active, targeted agents as triple therapy into chemoradiation protocols. Material and methods: cetuximab and bevacizumab have now been incorporated into phase I-II studies of preoperative chemoradiation therapy (CRT) for rectal cancer. The rationale of these combinations, early efficacy and toxicity data, and possible molecular predictors for tumor response are reviewed. Computerized bibliographic searches of Pubmed were supplemented with hand searches of reference lists and abstracts of ASCO and ASTRO meetings. Results: the combination of cetuximab and CRT can be safely applied without dose compromises of the respective treatment components. Disappointingly low rates of pathologic ...
Consensus principles from radiation biology were used to describe a generic set of nonlinear, first-order differential equations for modeling of toxicity-induced compensatory cell kinetics in terms of sublethal injury, repair, direct killing, killing of cells with unrepaired sublethal injury, and repopulation. This cellular model was linked to a probit model of hematopoietic mortality that describes death from infection and/or hemorrhage between {approximately} 5 and 30 days. Mortality data from 27 experiments with 851 doseresponse groups, in which doses were protracted by rate and/or fractionation, were used to simultaneously estimate all rate constants by maximum-likelihood methods. Data used represented 18,940 test animals distributed according to: (mice, 12,827); (rats, 2,925); (sheep, 1,676); (swine, 829); (dogs, 479); and (burros, 204). Although a long-term, repopulating hematopoietic stem cell is ancestral to all lineages needed to restore normal ...
The present study was undertaken to determine the involvement of calcium-protein kinase C pathway in the mechanism of action of Escherichia coli heat stable enterotoxin (STa) apart from STa-induced activation of guanylate cyclase in human colonic carcinoma cell line COLO-205, which was used as a model cultured cell line to study the mechanism of action of E. coli STa. In response to E. coli STa, protein kinase C (PKC) activity was increased in a time-dependent manner with its physical translocation from cytosol to membrane. Inhibition of the PKC activity in membrane fraction and inhibition of its physical translocation in response to IP_3-mediated calcium release inhibitor dantrolene suggested the involvement of intracellular store depletion in the regulation of PKC activity. Among different PKC isoforms, predominant involvement of calcium-dependent protein kinase C (PKC#alpha#) was specified using isotype-specific ...
Expression of IGF-2 and changes in its expression in response to systemic endocrine alterations have not been demonstrated for adipocytes. Adipocytes were induced to develop within cultures of 3T3-L1 cells using a medium containing 0.5mM isobutylmethylxanthine, 1uM insulin and 100ng hydrocortisone/ml for 48 hours of exposure. Cultures containing developing adipocytes were incubated with 10% pig serum and 1 uM insulin for several days. The resultant adipocyte cultures were then treated with either 10% pig serum, diabetic pig serum or hypophysectomized pig serum in DMEM for 48 hours. Adipocytes within the cultures were separated from undifferentiated cells using percoll density gradient centrifugation. Total RNA was isolated from adipocytes and dot blotted. Blots were probed with a {sup 32}P-cDNA probe for rat IGF-2. IGF-2 was expressed by the adipocytes and the pattern of expression showed specific differences between serum treatments; IGF-2 ...
Asynchronous Chinese hamster ovary (CHO) cells treated with conditioning hyperthermia (10 min at 45/sup 0/C) followed immediately by x irradiation with 4 Gy at room temperature display a decreased radiation response when either irradiated, or heated and irradiated again 24 h later. In addition, conditioning by 4 Gy of x radiation alone followed at 24 h by the combined heat and radiation treatment als resulted in a larger radiation D/sub 0/. Since the differential cell-cycle responses to heat- and x-ray-induced lethality are well established for CHO cells, the potential role of cell-cycle redistribution in the observed radiation desensitization was investigated by flow cytometry. At 24 h after the combined treatment, the fraction of the cells found in the G/sub 2/ + M portion of the DNA histograms was about three times that of the controls and there was a concomitant reduction in both the G/sub 1/ and S fractions. Similar ...
The feasibility was evaluated using MCNP-DSP, an analog Monte Carlo transport cod to simulate source-driven measurements. Models of an isolated Westinghouse 17x17 PWR fuel assembly in a 1500-ppM borated water storage pool were used. In the models, the fuel burnup profile was represented using seven axial burnup zones, each with isotopics estimated by the PDQ code. Four different fuel assemblies with average burnups from fresh to 32 GWd/MTU were modeled and analyzed. Analysis of the fuel assemblies was simulated by inducing fission in the fuel using a {sup 252}Cf source adjacent to the assembly and correlating source fissions with the response of a bank of {sup 3}He detectors adjacent to the assembly opposite the source. This analysis was performed at 7 different axial positions on each of the 4 assemblies, and the source-detector cross-spectrum signature was calculated for each of these 28 simulated measurements. The magnitude of the ...
A transplant experiment was conducted to determine whether standard metabolic rate (SMR) of a freshwater shrimp (Palaeomonetes paludosus) would be affected by exposure to trace element-enriched coal combustion waste (coal ash). Shrimp were transplanted into replicate cages in a coal ash-polluted site and a reference site for 8 months. The coal ash-polluted site was characterized by elevated sediment concentrations of As, Cd, Cr, Cu, Ni, Pb and Se compared to sediments in the reference site. After 8 months in the study sites, shrimp in the polluted site appeared to have accumulated As, Cd and Se from the habitat, but there were on differences in survival between the study sites. However, mean SMR of shrimp (measured as O{sub 2} consumption at rest) held in the polluted site was 51% higher than mean SMR of shrimp held in the reference site. The elevation in SMR indicates that the energetic costs of maintenance are greater for shrimp chronically exposed to the coal-ash polluted enviorment ...
A systematic study of structure-mechanical properties relation is reported for MoSi{sub 2}-SiC nanolayer composites. Alternating layers of MoSi{sub 2} and SiC were synthesized by DC magnetron and rf-diode sputtering, respectively. Cross-sectional transmission electron microscopy was used to examine three distinct reactions in the specimens when exposed to different annealing conditions: Crystallization and phase transformation of MoSi{sub 2}, crystallization of SiC, and spheroidization of the layer structures. Nanoindentation was employed to characterize the mechanical response as a function of structural changes. As-sputtered material exhibits amorphous structures in both types of layers and has a hardness of 11 GPa and a modulus of 217GPa. Subsequent heat treatment induces crystallization of MoSi{sub 2} to form the C40 structure at 500C and SiC to form the a structure at 700C. The crystallization process is directly ...
The most important factor in assessing radiologic risk is ensuring scientific means for evaluation of the radioactive release impact upon humans and organisms. To evaluate quantitatively this impact not only knowledge of radioactivity distribution in these dynamical systems is necessary but also understanding the transfer mechanisms between ecosystem components is needed. Thus a complete radioecologic study appear to be very complex and needs defining the source term, dynamic description of radionuclides behavior in the ecosystem, estimation of radiation doses in the major components of the ecosystem and finally the effects of radiation doses upon different parts of the systems. A diagram of the steps implied in evaluation of the effects due to radioactive effluent release in the environment is presented and discussed. The following steps are described: - identification of radioactive sources, as well as their input rate. Presence of noxious materials such as heavy metals or some ...
We previously reported the identification of a new family of plant methyltransferases (MTs), named the SABATH family, that use S-adenosyl-l-methionine (SAM) to methylate a carboxyl moiety or a nitrogen-containing functional group on a diverse array of plant compounds. The Arabidopsis genome alone contains 24 distinct SABATH genes. To identify the catalytic specificities of members of this protein family in Arabidopsis, we screened recombinantly expressed and purified enzymes with a large number of potential substrates. Here, we report that the Arabidopsis thaliana gene At3g44860 encodes a protein with high catalytic specificity towards farnesoic acid (FA). Under steady-state conditions, this farnesoic acid carboxyl methyltransferase (FAMT) exhibits K{sub M} values of 41 and 71 {mu}M for FA and SAM, respectively. A three-dimensional model of FAMT constructed based upon similarity to the experimentally determined structure of Clarkia breweri salicylic acid methyltransferase (SAMT) ...
The responses of ramets of hybrid poplar (Populus spp.) (HP) clones NE388 and NE359, and seedlings of red maple (Acer rubrum, L.) to ambient ozone (O_3) were studied during May-September of 2000 and 2001 under natural forest conditions and differing natural sunlight exposures (sun, partial shade and full shade). Ambient O_3 concentrations at the study site reached hourly peaks of 109 and 98 ppb in 2000 and 2001, respectively. Monthly 12-h average O_3 concentrations ranged from 32.3 to 52.9 ppb. Weekly 12-h average photosynthetically active radiation (PAR) within the sun, partial shade and full shade plots ranged from 200 to 750, 50 to 180, and 25 to 75 #mu#mol m"-"2 s"-"1, respectively. Ambient O_3 exposure induced visible foliar symptoms on HP NE388 and NE359 in both growing seasons, with more severe injury observed on NE388 than on NE359. Slight foliar symptoms were observed on red maple seedlings during the 2001growing season. Percentage of ...
Control of pressure transients in a hydraulic system may be important and necessary to avoid failures and to improve the efficiency of operation. Flow restricting devices can result in a decrease in the peak pressure, but may change the response time. The response time has an important effect on both operator and operator perceived smoothness. The response time should correspond to how fast a system responds to a given disturbance at the system boundary. Occasionally the appropriate response time is not easily determined. This study is on the response time characteristics in the hydraulic system studied for the control of response time.
Studies fail to find uniform effects of age-related or induced hypogonadism on human sexual function. We examined the effects of induced hypogonadism on sexual function in healthy men and women...Full Text Available
The author derives to which of the three types an irreducible UA representation which is obtained with the procedure of generalised induction belongs. The question whether or not the irreducible induced UA representations are on standardform is analysed. The results hold as well for induced PUA representations. (Auth.).
Many patients are currently suffering from nickel (Ni)-induced allergic contact dermatitis (ACD). There have been few Korean studies dealing with the threshold of Ni-induced ACD and quantifying the...Full Text Available
We introduce cyclophosphamide-induced alopecia (CYP-IA) in C57BL-6 mice as a clinically relevant model for studying the biology of chemotherapy-induced alopecia and for developing anti-alopecia drugs....Full Text Available
The issue of beam-induced damage on diffractive hard X-ray optics is addressed. For this purpose a systematic study on the radiation damage induced by a high-power X-ray beam is carried out in both...Full Text Available
Several organophosphate and organochlorine compounds, including pesticides commonly found in the Great Lakes basin, have the potential to induce immunotoxicity. Because of biomagnification and accumulation...Full Text Available
Neutron-induced soft error rates (SER`s) of subhalf-micron CMOS SRAM and Latch circuits were studied both experimentally and analytically to investigate cosmic ray neutron-induced soft errors (SE`s). Because the neutron beam used in the measurement has an energy spectrum similar to that of sea-level atmospheric neutrons, the SER data corresponds to those induced by cosmic ray neutrons. The {alpha}-particle induced SER`s were also measured for comparison with the neutron-induced SER`s. Neutron-induced SE`s occurred in both circuits. On the other hand, {alpha}-induced SE`s occurred in SRAM, but not in the Latch circuit. The measured SER`s agreed with simulated results. The authors discussed the significance of how cosmic ray neutrons affects CMOS circuits at ground level.
Lens-induced glaucoma comprises a number of different glaucomatous processes occurring in the elderly that share in common the role of the crystalline lens in the mechanism of increase in intraocular...Full Text Available
In rats, drug-induced depression of the central nervous system has been shown generally to be associated with an elevation in level of total acetylcholine in the brain. This generalization held true...Full Text Available
Dependent variables in research on problem behavior typically are based on measures of response repetition, but these measures may be problematic when behavior poses high risk or when its occurrence...Full Text Available
We quantified antibody responses to the HCV proteome that are associated with sustained virologic response (SVR) in HIV/HCV co-infected patients treated with pegylated interferon and ribavirin....Full Text Available
BackgroundReplication capacity (RC) of specific HIV isolates is occasionally blamed for unexpected treatment responses. However, the role of viral RC in response to antiretroviral...Full Text Available
An anomaly in the continuous X-ray (CXR) response of filled cables is described. A systematic investigation of this anomaly is pursued with a single cable type and a model explaining the anomaly is presented. The effect of the anomaly on the accuracy of CXR measurement of SGEMP response is discussed.
The dielectrophoretic (DEP) crossover method has been applied to the detection of cell responses to toxicants. Time and dose responses of the human cultured leukemia (HL-60) line were measured...Full Text Available
BackgroundVariable platelet response to clopidogrel has been widely observed. Studies have shown that the mean aggregation response to clopidogrel can be changed...Full Text Available
Behavioral responses to labellar stimulation with 19 L-amino acids were predicted on the basis of electrophysiological responses of largest labellar hairs. With the exceptions alanine, aspartic...Full Text Available
In laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS), the properties of laser-generated aerosols, such as size and composition, are crucial for matrix-independent quantification. In this study, the aerosol particle morphology and elemental composition generated by two state-of-the-art laser systems (ArF excimer nanosecond-UV laser and Ti:sapphire femtosecond-IR laser) were investigated by electron microscopic techniques. Electrostatic sampling of the aerosols directly onto transmission electron microscopy (TEM) grids allowed us to study the morphology and elemental composition of the aerosols using TEM and TEM-EDX (energy dispersive X-ray spectroscopy) analyses, respectively. The results of the electron microscopic studies were finally compared to the LA-ICPMS signals of the main matrix components. The investigations were carried out for non-conducting materials (glass and zircon), metallic samples (steel and brass) and semiconductors (sulfides). The studies ...
The biomedical and ecological interest for the microwave impact on the Earth biosphere is continuously increased since the industrial, military and communication activities strongly contribute to the electromagnetic stress of living bodies. In the next the authors present some of the main results obtained regarding the microwave exposure of various types of biological material: bacteria, fungi, young plant seedlings, dry seeds, animal tissues. The electromagnetic exposure was carried out in open space in well controlled environmental conditions by using 10.75 GHz/1 m W cm{sup -2} microwaves. Biochemical assays and cytogenetic tests have been carried out to reveal the changes induced post irradiation. The response of some pathogen bacteria, have been emphasized by means of turbidimetric measurements - the stimulatory effect being noticed at the level of the microbial population density (the stimulation of the human body microbial flora seems to ...
Full text: Lung cancer is responsible for most of the cancer related deaths and calls for new approaches to control the menace. In the present study chemopreventive efficacy of curcumin and quercetin was investigated against benzo(a)pyrene (BP) induced lung carcinogenesis. The mice were segregated into five groups which included normal control, BP treated, BP+curcumin treated, BP+quercetin treated and BP+curcumin+quercetin treated groups. The morphological and histological analyses of tumor nodules confirmed lung carcinogenesis, after 22 weeks of single i.p. injection of BP at a dose of 100 mg/Kg body weight to mice. Tumor incidence and tumor multiplicity were observed to be 88% and 1.75, respectively in the BP treated mice. A statistically significant increase in the uptake of "3H thymidine indicative of increased DNA synthesis which in turn is the marker of uncontrolled cancer cell proliferation, was observed in the lung slices of BP treated ...
We report a search for small RNAs (sRNAs) in the low-GC, gram-positive human pathogen Streptococcus pneumoniae. Based on bioinformatic analyses by Livny et al. (J. Livny, A. Brencic, S. Lory, and M. K. Waldor, Nucleic Acids Res. 34:3484-3493, 2006), we tested 40 candidates by Northern blotting and confirmed the expression of nine new and one previously reported (CcnA) sRNAs in strain D39. CcnA is one of five redundant sRNAs reported by Halfmann et al. (A. Halfmann, M. Kovacs, R. Hakenbeck, and R. Bruckner, Mol. Microbiol. 66:110-126, 2007) that are positively controlled by the CiaR response regulator. We characterized 3 of these 14 sRNAs: Spd-sr17 (144 nucleotides [nt]; decreased in stationary phase), Spd-sr37 (80 nt; strongly expressed in all growth phases), and CcnA (93 nt; induced by competence stimulatory peptide). Spd-sr17 and CcnA likely fold into structures containing single-stranded regions between hairpin structures, whereas Spd-sr37 ...
We have previously reported that FSH stimulates flux of 45Ca2+ into cultured Sertoli cells from immature rats via voltage-sensitive and voltage-independent calcium channels. In the present study, we show that this effect of FSH does not require cholera toxin (CT)- or pertussis toxin (PT)-sensitive guanine nucleotide binding (G) protein or activation of adenylate cyclase (AC). Significant stimulation of 45Ca2+ influx was observed within 1 min, and maximal response (3.2-fold over basal levels) was achieved within 2 min after exposure to FSH. FSH-stimulated elevations in cellular cAMP paralleled increases in 45Ca2+ uptake, suggesting a possible coupling of AC activation to 45Ca2+ influx. (Bu)2cAMP, however, was not able to enhance 45Ca2+ uptake over basal levels at a final concentration of 1000 microM, although a concentration-related increase in androstenedione conversion to estradiol was evident. Exposure of Sertoli cells to CT (10 ng/ml) consistently stimulated ...
The specificity of the hemodynamic response function (HRF) is determined spatially by the vascular architecture and temporally by the evolution of hemodynamic changes. The stimulus duration...Full Text Available
Senescence is regarded as a physiological response of cells to stress, including telomere dysfunction, aberrant oncogenic activation, DNA damage, and oxidative stress. This stress response has an antagonistically...Full Text Available
We explored transcriptional responses of the fission yeast Schizosaccharomyces pombe to various environmental stresses. DNA microarrays were used to characterize changes in expression...Full Text Available
BACKGROUND: Cuba's response to the human immunodeficiency virus (HIV) epidemic has been to conduct mass testing of the population to ascertain seroprevalence, to enforce mandatory relative quarantine...Full Text Available
We present a technique for identifying the amino acids responsible for a loss of immunoreactivity in response to treating an antigen with a chemical modifier. This is of particular interest...Full Text Available
Four techniques for using LIDAR in Search and Rescue Operations will be discussed. The topic will include laser retroreflection, laser-induced fluorescence in the visible, laser-induced fluorescence during daylight hours, and laser-induced fluorescence in the uv. These techniques use high-repetition rate lasers at a variety of frequencies to induce either fluorescence in dye markers or retroreflection from plastic corner cubes on life preservers and other emergency markers.
With an objective to perform three-dimensional analysis with high accuracy in using the electromagnetic exploration method, characteristics in electromagnetic response were analyzed, and conditions for acquiring necessary data were discussed. The discussion defined a parameter called `response anomaly` which uses response from media to standardize response only from substances with abnormal resistivity. The receivers were located uniformly on the same plane, and the response anomaly was derived from electromagnetic response from each of the three horizontal and vertical components at each receiving point, which was expressed as a contour map. The parameter for the abnormal body was consisted of location and resistivity contrast with media. Discussions using the contour map were given on the response when these factors for the parameter were ...
The authors review two types of simulators for the analysis of cosmic ray neutron-induced soft errors (SE's). One of them is the neutron-induced soft error simulator (NISES). A recently proposed nuclear reaction theory forms the foundation for the nuclear reaction database used in NISES. The other simulator, the simplified simulator MBGR, is based on a modified version of the burst generation rate (BGR) model. Both simulators accurately simulate neutron-induced SE rates (SER's). MBGR actually provides an easier and quicker estimation of neutron-induced SER's than NISES. On the other hand, NISES covers more applications; it simulates neutron-induced charge collection, multiple-bit SE, and [alpha]-induced SE analysis.
The authors review two types of simulators for the analysis of cosmic ray neutron-induced soft errors (SE's). One of them is the neutron-induced soft error simulator (NISES). A recently proposed nuclear reaction theory forms the foundation for the nuclear reaction database used in NISES. The other simulator, the simplified simulator MBGR, is based on a modified version of the burst generation rate (BGR) model. Both simulators accurately simulate neutron-induced SE rates (SER's). MBGR actually provides an easier and quicker estimation of neutron-induced SER's than NISES. On the other hand, NISES covers more applications; it simulates neutron-induced charge collection, multiple-bit SE, and #alpha#-induced SE analysis
Radio-biologists have pointed out a novel radiobiological phenomenon observed in many tumor and normal cell lines: hyper-radiosensitivity to very low-dose (H.R.S.) followed by induced radioresistance (I.R.R.) after a threshold dose of 0.1-0.3 Gy that depends on the cell line. Radioresistance at high dose (i.e. higher than 0.5 Gy) and metastatic potential of tumor cells are likely major factors of failure in radiotherapy. A careful review of literature suggests that: 1) radiotherapy does not increase the metastatic potential of tumor cells; 2) radioresistance at high dose and metastatic potential are not related. However, inside a given tumor cell line, highly metastatic clones may elicit more cells showing H.R.S; or are more radiosensitive at high dose than poorly metastatic ones. Recent data obtained from molecular techniques (comet and immunofluorescence assays) applied to single cells irradiated at very low radiation doses (1-100 mGy) suggest that DNA ...
The neuronal nicotinic acetylcholine receptor {alpha}7 subunit is a member of a family of ligand-gated ion channels, and is the only subunit know to bind {alpha}-bungarotoxin in mammalian brain. {alpha}-Bungarotoxin binding sites are known to be more abundant in the hippocampus of mouse strains that are particularly sensitive to nicotine-induced seizures. The {alpha}7 receptor is highly permeable to calcium, which could suggest a role in synaptic plasticity in the nervous system. Auditory gating deficiency, an abnormal response to a second auditory stimulus, is characteristic of schizophrenia. Mouse strains that exhibit a similar gating deficit have reduced hippocampal expression of the {alpha}7 subunit. We have cloned and sequenced the full length cDNA for the mouse {alpha}7 gene (Acra-7) and characterized its gene structure. The murine {alpha}7 shares amino acid identity of 99% and 93% with the rat and human {alpha}7 subunits, respectively. ...
The hardening and embrittlement of reactor pressure vessel (RPV) steels is of great concern in the actual nuclear power plant life assessment. This embrittlement is caused by irradiation-induced damage, like vacancies, interstitials, solutes and their clusters. The current procedure to estimate material properties for the irradiated pressure vessels is based on Charpy-V tests of identical material located at the inner shell of the reactor. But the reason for the embrittlement of the materials is not yet totally known. The real nature of the irradiation damage should thus be examined as well as its evolution in time. Fe-Cu binary alloys are often used to mimic the behaviour of such steels. Their study allows. Identifying some of the defects responsible of the hardening, especially when compared to pure iron or C-micro-alloyed iron. More recently the influence of manganese and nickel in low-Cu RPV steels has become a significant topic. Thus in ...
Full text: It is known that the ion implantation of germanium single crystals at room temperature results in drastic alteration of the germanium surface and the formation of cellular relief. Voids were found into the near-surface damage layer. The intersection of these voids with the germanium surface, as result of sputter etching, forms cellular relief. However, exact mechanism responsible for formation of the voids is not known. A 10 and 30 keV Ga"+ irradiation of Ge #left brace#100#right brace# crystal at room temperature was carried out using a focused ion beam (FIB) system with a dose in the range 0.5x10"1"2 to 1.5x10"1"4 ion/cm"2. The topology of the modified germanium surface and the structure of the radiation damage was studied using imaging facilities of the FIB systems and transmission electron microscopy. The strong cellular structure of Ge was observed after an ion dose of 3x10"1"3 ion/cm"2. High-resolution TEM showed a complex structure of the ...
Although Bois noir is one of the main phytoplasma diseases of grapevine, the gene expression and enzyme activities that underlie physiological changes occurring in symptomatic and recovered (with spontaneous or induced symptom remission) plants are mostly unknown. Bois noir symptomatic leaves (September 2006, 2007) and symptomless leaves from infected symptomatic plants (September 2007) of Sangiovese (moderately susceptible) and Chardonnay (highly susceptible) cultivars were collected. Moreover, leaves from infected symptomless plants of both cultivars were harvested in June 2007. Leaves from recovered plants were also collected in the same periods. In recovered plants of both cultivars, class III chitinase and almost every time phenylalanine ammonia-lyase and chalcone synthase expression were increased for all collection periods. In symptomatic leaves of both cultivars, the expressions of the same genes were up-regulated and also those of ?-1,3-glucanase and ...
To study the regulation of adipose tissue lipoprotein lipase (LPL) in human adipocytes, omental adipose tissue was obtained from healthy subjects and digested in collagenase. The isolated adipocytes thus obtained were suspended in Medium 199 and cultured at 37 degrees C. Cell viability was demonstrated in adipocytes cultured for up to 72 h by constancy of cell number, cell size, trypan-blue exclusion, and specific /sup 125/I-insulin binding. In addition, chloroquine induced an increase in cell-associated /sup 125/I-insulin at 24, 48, and 72 h after preparation. Thus, isolated adipocytes retained their ability to bind, internalize, and degrade insulin. LPL was measured as activity secreted into the culture medium (CM), released from cells by heparin (HR), and extracted from cell digests. A broad range of heparin concentrations produced a prompt release of LPL from a rapidly replenishable pool of cellular activity. When cells were cultured in medium containing 10% ...
The effect of various window layers for InP solar cells are studied. Window materials that have type 1 and type 2 alignment in the window/emitter interface are compared. All window materials that form a type 2 alignment with InP, such as Al{sub 0.20}In{sub 0.80}P, Ga{sub 0.20}In{sub 0.80}P, Al{sub 0.55}In{sub 0.45}As and Al{sub 0.60}In{sub 0.40}P, cause a high interface recombination velocity, which deteriorates the carrier collection. This recombination takes place due to the spatially indirect quantum well transition between the triangular quantum wells formed in the interface. ZnSe as a window layer material with type 1 alignment does not have this problem, but still decreased response in the short wavelength region is observed due to misfit dislocation induced trap sites. Future prospects for the window layer development for InP are discussed. The discussion is extended also to other III-V semiconductor based solar cell materials, such as ...
Insect host/parasitoid interactions are co-evolved systems in which host defenses are balanced by parasitoid mechanisms to disable or hide from host immune effectors. Although there is a rich literature on these systems, parasitoid immune-disabling mechanisms have not been fully elucidated. Here we report on a newly discovered immune-disabling mechanism in the Pieris rapae/Pteromalus puparum host/parasitoid system. Because venom injections and parasitization suppresses host phagocytosis, we turned attention to the P. rapae scavenger receptor (Pr-SR), posing the hypothesis that P. puparum venom suppresses expression of the host Pr-SR gene. To test our hypothesis, we cloned a full-length cDNA of the Pr-SR. Multiple sequences alignment showed the deduced amino acid sequence of Pr-SR is similar to scavenger receptors of other lepidopterans. Bacterial and bead injections induced Pr-SR mRNA and protein expression, which peaked at 4h post-bead injection. Venom injection ...
Measurements of temperature and NO concentration in laminar, partially premixed methane-air flames stabilized on a ceramic burner in coflow are reported. The NO concentration and temperature were determined by laser-induced fluorescence (LIF) and coherent anti-Stokes Raman scattering (CARS), respectively. Upstream heat loss to the burner was varied by changing the exit velocity of the fuel-air mixture at a constant equivalence ratio of 1,3; this alters the structure of the flame from an axisymmetric Bunsen-type to a strongly stabilized flat flame. To facilitate analysis of the results, a method is derived for separating the effects of dilution from those of chemical reaction based on the relation between the measured temperature and the local mixture fraction, including the effects of upstream heat loss. Using this method, the amount of NO formed during burnout of the hot, fuel-rich combustion products can be ascertained. In the Bunsen-type flame, it is seen that ...
The Greek energy economy in response to the rising energy demand yielded to the pressure to develop new sources, particularly since the early closing of the Aliveri mine was approaching. The well known lignite deposits in the Megalopolis Basin, with approximately 380 MMt of economically recoverable fuel, had remained undeveloped since its low heat value, averaging 4012 kJ (960 kcal/kg), had been considered in all countries of the world to be of too poor quality to be economically usable in thermal power plants. With the onset of energy shortages in Greece, which in the course of the year 1967 led to intermittent interruptions of power, finally induced the Public Power Corp., within a German economic assistance agreement to advertise an idea competition among German consortia. In 1967 various planning consortia submitted their plans for the treatment of the Megalopolis open-pit mine and for the laying out of the still-to-be-added power plant. In ...
Cigarette smoking is the major environmental risk factor for bladder cancer in humans. Aromatic amines, potent DNA-reactive bladder carcinogens present in cigarette smoke, contribute significantly. However, increased cell proliferation, caused by direct mitogenesis or in response to cytotoxicity, may also play a role since urothelial hyperplasia has been observed in human cigarette smokers. We examined the urothelial effects of cigarette smoke (whole body inhalation exposure (Teague) system) in female C57BL/6 mice at various times in two studies, including reversibility evaluations. In both studies, no urothelial hyperplasia was observed by light microscopy in any group. However, in study 1, the Ki-67 labeling index (LI) of the urothelium was significantly increased in the smoke exposed group compared to controls through 3 months, but was not present at 6, 9 or 12 months even with continued exposures. In the groups that discontinued smoke exposure, it returned to ...
The ceramic composite armor has been lucubrated in the past 40 years. Ceramic can provide the same protection as metal, but it has lighter weight than metal. Ceramic has excellent ability of resisting kinetic energy projectile, because it can transfer energy to a large range by its fragmented cone and has higher ability of eroding the projectile than metal. But the researches indicated the full potential of the ceramic hard face has not been achieved because the significant interface between ceramic and metal has the unfavorable impedance effects and would induce tensile failure. FGM is a new type composite with continuous transition from ceramic to metal; it has no significant discrete materials interfaces between ceramic and metal. This paper deals with the impact response of Ceramic/FGM/Metal armor by numerical and theoretical methods. Firstly, the ability of TiB{sub 2}/FGM/Metal armor resisting KE projectile is analyzed by Dytran FEM ...
Cdc7 kinase plays an essential role in firing of replication origins by phosphorylating components of the replication complexes. Cdc7 kinase has also been implicated in S phase checkpoint signaling downstream of the ATR and Chk1 kinases. Inactivation of Cdc7 in yeast results in arrest of cell growth with 1C DNA content after completion of the ongoing DNA replication. In contrast, conditional inactivation of Cdc7 in undifferentiated mouse embryonic stem (ES) cells leads to growth arrest with rapid cessation of DNA synthesis, suggesting requirement of Cdc7 functions for continuation of ongoing DNA synthesis. Furthermore, loss of Cdc7 function induces recombinational repair (nuclear Rad51 foci) and G2/M checkpoint responses (inhibition of Cdc2 kinase). Eventually, p53 becomes highly activated and the cells undergo massive p53-dependent apoptosis. Thus, defective origin activation in mammalian cells can generate DNA replication checkpoint signals. ...
A feature of the Fast Flux Test Facility (FFTF) is that fuel assemblies can be stored within the reactor vessel, either for future use in the core or for temporary storage of spent fuel. Due to the close proximity of fuel assemblies stored in the in-vessel storage (IVS) locations to the ex-vessel flux monitors (EVFMs), neutrons originating in the stored fuel can result in significant contributions to the total EVFM signals. The paper shows EVFM-induced electronic current data during operation at full power for FFTF power cycles 1 through 7. The data were obtained early in each cycle so that signal drift due to core burnup could be ignored. The differences in currents are attributed to differences in cycle-to-cycle core and stored fuel loadings. At the beginning of cycle 1 there were no fuel assemblies stored in IVS. Subsequent to cycle 1, the EVFM currents have been higher than those for cycle 1, by as much as a factor of #approx# 2, and this is attributed to fuel ...
Extracellular ATP stimulates transmembrane ion fluxes in the mouse macrophage cell line J774. In the presence of Mg2+, nonhydrolyzable ATP analogs and other purine and pyrimidine nucleotides do not elicit this response, suggesting the presence of a specific receptor for ATP on the macrophage plasma membrane. One candidate for such a receptor is the ecto-ATPase expressed on these cells. We, therefore, investigated the role of this enzyme in ATP-induced /sup 86/Rb+ efflux in J774 cells. The ecto-ATPase had a broad nucleotide specificity and did not hydrolyze extracellular ATP in the absence of divalent cations. /sup 86/Rb+ efflux was not blocked by inhibition of the ecto-ATPase and did not require Ca2+ or Mg2+. In fact, ATP-stimulated /sup 86/Rb+ efflux was inhibited by Mg2+ and correlated with the availability of ATP4- in the medium. In the absence of divalent cations, the slowly hydrolyzable ATP analogs adenosine 5'-(beta, ...
We have tested the suitability of a new single-aliquot regenerative-dose protocol for estimating the equivalent dose (D_e) in polymineral fine grains extracted from colluvia from various sites in Germany. First, we report the behaviour of three OSL signals: (i) blue-stimulated, (ii) infrared-stimulated luminescence, and (iii) blue-stimulated luminescence following infrared (IR) stimulation, using a near-UV (290-380 nm) detection window in each case. For these three signals, there is a significant change in sensitivity with regeneration cycle; this change can be compensated for using the response to a fixed test dose after each natural or regenerated measurement. The source of the three luminescence signals is then investigated using pulse-anneal and elevated-temperature experiments. Fading tests on laboratory-induced signals show that although the IR signals fade by up to 23% in 15 days at 100 deg. C, the post-IR blue signals are stable. The ...
The effects of the antioxidants, vitamin E, propyl gallate, 2-t-butyl-4-methoxy phenol (BHA), 2,6-di-t-butyl-4-methoxy phenol (BHT), nor-dihydroguaiaretic acid (NDGA) and diphenyl-p-phenylene diamine (DPPD) in concentrations ranging between 0.001 per cent and 0.1 per cent have been tested on lipid peroxide formation in synthetic diet mixtures containing herring oil (10 per cent) mixed with starch (90 per cent) irradiated with #gamma#-ray doses of 100 to 2000 krad. On a weight basis NDGA, DPPD, BHA and BHT were most effective and vitamin E and propyl gallate were least effective. An antioxidant concentration of 0.01 per cent normally protected against peroxide formation after a dose of 500 krad but if the dose was increased to 1000 or 2000 krad, much higher doses of antioxidant, up to 0.1 per cent, were required to give protection. Antioxidants prevented peroxide developing during post-irradiation storage even when added after irradiation. Antioxidants were partially or completely ...
Culex mosquitoes introduce the pathogens responsible for filariasis, West Nile virus, St. Louis encephalitis, and other diseases into humans. Currently, traps baited with oviposition semiochemicals play an important role in detection efforts and could provide an environmentally friendly approach to controlling their populations. The odorant binding proteins (OBPs) in the female's antenna play a crucial, if yet imperfectly understood, role in sensing oviposition cues. Here, we report the X-ray crystallography and NMR 3D structures of OBP1 for Culex quinquefasciatus (CquiOBP1) bound to an oviposition pheromone (5R,6S)-6-acetoxy-5-hexadecanolide (MOP). In both studies, CquiOBP1 had the same overall six-helix structure seen in other insect OBPs, but a detailed analysis revealed an important previously undescribed feature. There are two models for OBP-mediated signal transduction: (i) direct release of the pheromone from an internal binding pocket in a ...
In vertebrates, the positioning of the internal organs relative to the midline is asymmetric and evolutionarily conserved. A number of molecules have been shown to play critical roles in left-right patterning. Using representational difference analysis to identify genes that are differentially expressed on the left and right sides of the chick embryo, we cloned chick Claudin-1, an integral component of epithelial tight junctions. Here, we demonstrate that retroviral overexpression of Claudin-1, but not Claudin-3, on the right side of the chick embryo between HH stages 4 and 7 randomizes the direction of heart looping. This effect was not observed when Claudin-1 was overexpressed on the left side of the embryo. A small, but reproducible, induction of Nodal expression in the perinodal region on the right side of the embryo was noted in embryos that were injected with Claudin-1 retroviral particles on their right sides. However, no changes in Lefty,Pitx2 or cSnR expression were observed. ...
A solid-state precipitation process was used to prepare superconducting tapes containing an A15 phase, V/sub 3/Ga or Nb/sub 3/Al, in a ductile niobium or vanadium containing BCC matrix. Ingots weighing as large as 30 to 50 gms of V-(14 approx. 19 at. %) Ga and Nb-(13 approx. 22 at. %) Al were prepared by arc-melting, homogenized, quenched, warm-rolled over 99% into tape, and aged at temperatures in the range 600/sup 0/C to 1000/sup 0/C to precipitate the superconducting A15 phase. The features demonstrated by the process are very attractive for practical applications. In the V-Ga system, transmission electron microscopy (TEM) studies revealed the A15 precipitates in an elongated form. However, for the Nb-Al samples, deformed and aged at 750/sup 0/C, TEM studies revealed A15 precipitation in fine equi-axed particles which formed as a semi-continuous network over sub-grain boundaries formed by the recovery of deformation-induced dislocations. In the V-Ga system, the ...
The formation and properties of Pd{sub 2}Si formed by focused ion beam implantation of Pd ions into Si is presented in this thesis. An extensive microstructural study using transmission electron microscopy was undertaken and the as-implanted as well as annealed microstructure is shown. Results of other analysis techniques such as Rutherford back scattering and secondary ion mass spectrometry etc. are also presented. Kinetic information on the growth of Pd{sub 2}Si obtained by both microstructural and resistance measurements indicates that the activation energy for growth of the silicide is around 0.36 to 0.39 eV. This can be compared with the normally reported value of 1.5 eV for Pd{sub 2}Si formed by annealing thin film Pd on Si. The growth of the silicide was found to follow t{sup 1/2} kinetics. Microstructural observation of the as-implanted samples showed extensive in-situ formation of Pd{sub 2}Di and also surprisingly few defect structures. A heat transfer model for the ...
The formation and properties of Pd_2Si formed by focused ion beam implantation of Pd ions into Si is presented in this thesis. An extensive microstructural study using transmission electron microscopy was undertaken and the as-implanted as well as annealed microstructure is shown. Results of other analysis techniques such as Rutherford back scattering and secondary ion mass spectrometry etc. are also presented. Kinetic information on the growth of Pd_2Si obtained by both microstructural and resistance measurements indicates that the activation energy for growth of the silicide is around 0.36 to 0.39 eV. This can be compared with the normally reported value of 1.5 eV for Pd_2Si formed by annealing thin film Pd on Si. The growth of the silicide was found to follow t"1"/"2 kinetics. Microstructural observation of the as-implanted samples showed extensive in-situ formation of Pd_2Di and also surprisingly few defect structures. A heat transfer model for the implantation indicates no ...
A computerised glow curve deconvolution (CGCD) analysis was applied to the main dosimetric peak of #alpha#-Al_2O_3:C in order to study the effects of light on the glow curve shape. It was shown that both the light-induced signal and the light-induced fading effects tend to shift the main dosimetric peak to higher temperatures and at the same time change its shape. Furthermore it was confirmed that the magnitude of the light-induced signal depends on radiation history and, by increasing the duration of light exposure, the magnitude of the light-induced signal reaches a plateau, thereby implying the saturation of the phototransfer process. (author).
Several compounds were evaluated in nonhuman primates for their potential to induce neoplasms, especially hepatocellular carcinoma (HCC). The compounds can be classified into three groups: food contaminants, model rodent carcinogens, and nitrosamines. All three compounds in the food contaminants group, namely, aflatoxin B1, sterigmatocystin, and methylazoxymethanol acetate, induced HCC. None of the model rodent carcinogens tested consistently induced HCC in rhesus and cynomolgus monkeys. Three of four nitrosamines evaluated induced HCC in rhesus and cynomolgus monkeys. One nitrosamine, diethylnitrosamine, is a predictable and potent inducer of HCC and is useful for establishment of a nonhuman primate model for numerous oncologic studies.
In this effort, the nonlinear responses and stability of a spindle system supported by ball bearings are presented. The dynamics of this system is described by a set of second order differential equations with a nonlinear piecewise smooth force. The Floquet theory is applied to investigate the stability of the periodic solution. Due to the loss of contact between the raceways and balls in the ball bearing, the bending of the frequency response curves switch to the left at the weak resonance region, which is similar to the frequency response curves of a system with a soft spring. With the decrease of the bearing clearance, the bending of the frequency response curves switch to the right, which is similar to the frequency response curves of a system with a hard spring. Increase of the frequency ratio, the bending of frequency response curves transforms from left ...
Electrostatic torsional micro-mirrors have wide spread use in different industries for diverse purposes. This paper investigates the development of superharmonics and chaotic responses in electrostatic torsional micro-mirrors near the pull-in condition. Appearance of nonlinear phenomena is investigated in models accounting for and disregarding the coupling of torsional and flexural deflections. Analysis of the system response to step and harmonic excitation reveals the appearance of DC and AC symmetry breaking. Increasing the amplitude of harmonic excitation, the response in the form of distinct superharmonics changes to a broad band response, where there is loss of periodicity and the response becomes chaotic. Accounting for flexural deflections in coupled model reduces the voltage thresh...
Studies that estimate deficit probabilities in hydrothermal systems have generally ignored the response of demand to changing prices, in the belief that such response is largely irrelevant. We show that ignoring the response of demand to prices can lead to substantial over or under estimation of the probability of an energy deficit. To make our point we present an estimation of deficit probabilities in Chile's Central Interconnected System between 2006 and 2010. This period is characterized by tight supply, fast consumption growth and rising electricity prices. When the response of demand to rising prices is acknowledged, forecasted deficit probabilities and marginal costs are shown to be substantially lower. (author)
It is becoming increasingly evident that a linkage needs to exist between the siting of emergency response units and the routing of high level radioactive waste shipments. It is important to position the response teams so that the most efficient and effective emergency response can be provided. But the data needed to solve the siting problem are fragmented. This paper identifies the weak points in the data already available and suggests ways in which the data can be strengthened in a cost-effective manner. Among the weakest areas are estimates of the time required for various response events to occur, such as notification time, mobilization time, travel time, and containment time.
In modern quality engineering, dual response surface methodology is a powerful tool to model an industrial process by using both the mean and the standard deviation of the measurements as the responses. The least squares method in regression is often used to estimate the coefficients in the mean and standard deviation models, and various decision criteria are proposed by researchers to find the optimal conditions. Based on the inherent hierarchical structure of the dual response problems, we propose a Bayesian hierarchical approach to model dual response surfaces. Such an approach is compared with two frequentist least squares methods by using two real data sets and simulated data.
Eight patients, one male and seven females, with no pre-existing hypothalamic-pituitary disease, who developed symptoms of hypopituitarism following cranial irradiation for nasopharyngeal carcinoma were studied 5 years or more after radiotherapy. All were GH deficient. Four of the patients with no GH response during insulin tolerance tests (ITT) showed increased GH in response to synthetic human growth hormone releasing factor (GRF-44). Four patients had impaired cortisol responses to ITT, and gradual but diminished cortisol responses to ovine corticotrophin releasing factor (CRF-41). There was no significant difference between mean peak increments in response to ITT and those in response to CRF-41. TSH responses to TRH were delayed in five and absent in two patients; four of these had low free T4 index. Prolactin was raised in all seven ...
This thesis deals with the evaluation of Solar Grade Silicon (SoG-Si) purified by different techniques, and also the fabrication and characterization of high efficiency and advanced bifacial solar cells. In the beginning of Chapter 1, various SoG-Si production methods relevant for this work are qualitatively described. The three feedstock materials used in this work are from the Fluidized Bed Reactor (FBR) process, metallurgical feedstock-I and feedstock-II process. In metallurgical feedstock-I, the lifetime of the minority charge carriers in multicrystalline silicon (mc-Si) samples at the grain boundaries are found to be higher than the grains themselves possibly due to lower resistivities in the grain boundaries. The efficiency of the best solar cell obtained using the mc-Si metallurgical feedstock-I is 16.1%. It has been identified that the fast light induced degradation, whose magnitude is lower than that of a reference cell suggests the formation of a B-metal ...
The R and D activities of the institute focused on two major projects, ``Molecular and cellular environmental toxicology``, and ``Biophysics of multi-cellular systems``. For assessment of health risks emanating from the uptake of heavy metal compounds, work performed under the first mentioned project studies the formation of allergy-inducing metabolic products from membrane lipids, and the effects of related cellular signaling processes. These studies are accompanied by an approach to quantify and classify the toxicity of environmental organometallic compounds. Another major task is research into the pathogenesis of lung disease induced by dusts, gases, and gas-dust mixtures and the liberation of inflammatory agents by immunological cell reactions (alveolar macrophages). Atomic force microscopy is the tool used to visualize the related dynamic changes in bronchial cells. Studies for detection of the localisation and structure of the Fe-Mo ...
The results of the thermo-hydro-mechanical (THM) study of the FEBEX bentonite performed during FEBEX II are presented. The laboratory test program continued in part with the works carried out during FEBEX I, particularly in activities related to tests aimed to the calibration of the models, the acquisition of parameters by back-analysis and the improvement of the knowledge on the behaviour of expansive clays. But the program has also included tests on new areas: investigations about the influence of the microstructure changes in bentonite, of temperature and of the solute concentration on the behaviour of clay. Besides, several tests were proposed in order to understand the unexpected behaviour observed in the mock-up test, towards the end of year 2. Temperature effects on water retention curves in confined and unconfined conditions were determined, and swelling pressure, hydraulic conductivity and swelling and consolidation strains as a function of temperature were successfully ...
This SBIR Phase I developed neutron detectors made from gallium arsenide (GaAs) p-type/ intrinsic/n-type (P-I-N) diodes grown by metalorganic chemical vapor deposition (MOCVD) onto semi-insulating (S1) bulk GaAs wafers. A layer of isotonically enriched boron-10 evaporated onto the front surface serves to convert incoming neutrons into lithium ions and a 1.47 MeV alpha particle which creates electron-hole pairs that are detected by the GaAs diode. Various thicknesses of ''intrinsic'' (I) undoped GaAs were tested, as was use of a back-surface field (BSF) formed from a layer of Al{sub x}Ga{sub 1-x}As. Schottky-barrier diodes formed from the same structures without the p+ GaAs top layer were tested as a comparison. After mesa etching and application of contacts, devices were tested in visible light before application of the boron coating. Internal quantum efficiency (IQE) of the best diode near the GaAs bandedge is over 90%. The lowest dark current ...
We have established a reliable method to induce invasive and non-invasive carcinomas in the heterotopically transplanted urinary bladder of rats by repeated injection of N-methyl-N-nitrosourea (MNU),...Full Text Available
Global acetylation of histone H4 is a mark of gene transcriptional activation. The c-Myc transcription factor binds to specific DNA sites in cellular chromatin and induces the acetylation of...Full Text Available
A brief overview if provided of selected reports presented at the International Symposium on Molecular Mechanisms of Radiation- and Chemical Carcinogen-Induced Cell Transformation held at Mackinac Island, Michigan on September 19-23, 1993.
BackgroundWe examined the effects of short-term consumption of whey protein isolate on muscle proteins and force recovery after eccentrically-induced muscle damage in healthy individuals.MethodsSeventeen...Full Text Available
The hemagglutinin (HA) glycoprotein of influenza virus performs two critical roles during infection: it binds virus to cell surface sialic acids, and under mildly acidic conditions it induces fusion...Full Text Available
Hypoxia inducible factor-1 (HIF-1) promotes tumor cell adaptation to microenvironmental stress. HIF-1 is up-regulated in irradiated tumors and serves as a promising target for radiosensitization....Full Text Available
An overall hypothesis for benzene-induced leukemia is proposed. Key components of the hypothesis include a) activation of benzene in the liver to phenolic metabolites; b) transport of these metabolites...Full Text Available
The purpose of this study was to determine whether resistance exercise training-induced reductions in inflammation are mediated via melanocortin 3 receptor expression in obese (BMI 32.7 ± 3.7)...Full Text Available
BackgroundContrast-induced nephropathy is the leading cause of in-hospital acute renal failure. This side effect of contrast agents leads to increased morbidity, mortality, and health...Full Text Available
An ultrasensitive laser-induced fluorescence detector was used with capillary electrophoresis for the study of 5-carboxy-tetramethylrhodamine. The raw signal from the detector provided roughly...Full Text Available
Interleukin 12 (IL-12) activates natural killer (NK) and T cells with the secondary synthesis and release of interferon-gamma (IFN-gamma) and other cytokines. IL-12-induced organ alterations are reported...Full Text Available
It has been observed that puncture of a lumbar disc may induce formation of a nodule on the surface of the disc and osteophytes. It is not known if this is based on the presence of a foreign tissue...Full Text Available
The morphogenesis of pulmonary edema and bronchiolar injury induced by the toxic furan, 4-ipomeanol, was studied by combined light and transmission electron microscopy. Weanling male CD-1 mice received...Full Text Available
A total of 626 patients undergoing a prostaglandin-induced abortion, the majority in the second trimester, have been analysed for complications occurring during inpatient treatment. Of the last 155...Full Text Available
Petal senescence, one type of programmed cell death (PCD) in plants, is a genetically controlled sequence of events comprising its final developmental stage. We characterized the pollination-induced...Full Text Available
ObjectiveThe primary objective of this study was to assess whether pentagastrin-induced panic symptoms are associated with release of free fatty acids (FFAs) in a manner that could...Full Text Available
Treatment of Japanese pines (P. densiflora and P. thunbergii) with paraquat induced a zone of lightwood. Determinations of turpentine and ether extractives contents in lightwoods showed high levels as compared with those in control woods. (Refs. 5).
BackgroundThe objective of this study was to gain insight into the molecular mechanism of induced cell death (apoptosis) by PYRROLO [1,2-b][1,2,5]BENZOTHIADIAZEPINES...Full Text Available
The measured result of charged multiplicity in cosmic-ray proton induced nuclear reaction from Chinese satellite emulsion is reported. The correlation of shower and heavy particles is discussed and compared with p-emulsion interactions.
BackgroundThe tumor microenvironment has been described as a critical milieu determining tumor growth and metastases. A pivotal role of metastasis-inducing S100A4 in the development...Full Text Available
The mechanism of chemotherapy-induced acceleration of ovarian aging is not fully understood. We used doxorubicin, a widely used cancer chemotherapeutic, in a variety of in vivo xenograft,...Full Text Available
The mechanism of influenza virus (INFV)-induced immunosuppression and the mode of inosiplex action against INFV infection were studied. INFV suppressed both anti-lipopolysaccharide and anti-sheep erythrocyte...Full Text Available
BackgroundThe complications of hypertension cause severe health problems in rural areas in China. We (i) screened the major factors inducing hypertensive complications and provided...Full Text Available
BackgroundSome breast cancer patients receiving anti-angiogenic treatment show increased metastases, possibly as a result of induced hypoxia. The effect of hypoxia on tumor cell...Full Text Available
Type II collagen-induced arthritis (CIA) in mice is an autoimmune experimental model for rheumatoid arthritis. Susceptibility to CIA is associated with certain major histocompatibility complex class...Full Text Available
Reversion-induced LIM protein (RIL) is a member of the ALP (actinin-associated LIM protein) subfamily of the PDZ/LIM protein family. RIL serves as an adaptor protein and seems to regulate cytoskeletons....Full Text Available
BackgroundThe maternally inherited, bacterial symbiont, parthenogenesis inducing (PI) Wolbachia, causes females in some haplodiploid insects to produce daughters...Full Text Available
Increased sensitivity to light-induced melatonin suppression characterizes some, but not all, patients with bipolar illness or seasonal affective disorder. The aim of this study was to test...Full Text Available
Activation-induced cytidine deaminase (AID) protein initiates Ig gene mutation by deaminating cytosines, converting them into uracils. Excision of AID-induced uracils by uracil-N-glycosylase...Full Text Available
Calorie restriction (CR) induces a metabolic shift towards mitochondrial respiration; however, molecular mechanisms underlying CR remain unclear. Recent studies suggest that CR-induced mitochondrial...Full Text Available
Heat shock proteins (Hsp) are a family of stress-inducible molecular chaperones that play multiple roles in a wide variety of animals. However, the roles of Hsps in parasitic nematodes remain largely...Full Text Available
AimTo assess the progression of bronchial reactivity (BR) and incidence of bronchial hyperreactivity (BH), exercise‐induced bronchoconstriction (EIB) and asthma in triathletes...Full Text Available
Accumulation of molecular damage and increased molecular heterogeneity are hallmarks of cellular aging. Mild stress-induced hormesis can be an effective way for reducing the accumulation of molecular...Full Text Available
Neonatal administration of the synthetic glucocorticoid, dexamethasone (DEX) retards brain growth, alters adult behaviors and induces cell death in the rat brain, thereby implicating glucocorticoids...Full Text Available
Cigarette smoke (CS) induces recruitment of inflammatory cells in the lungs leading to the generation of reactive oxygen species (ROS), which are involved in lung inflammation and injury. Nicotinamide...Full Text Available
PurposeTo investigate the effects of laser photocoagulation (LP)-induced ocular hypertension (OHT) on the survival and retrograde axonal transport of retinal ganglion cells (RGC),...Full Text Available
The speed of ethylene-induced leaf abscission in cotton (Gossypium hirsutum L. cv LG-102) seedlings is dependent on leaf position (i.e. physiological age). Fumigation...Full Text Available
Esophageal perforation is associated with a significant risk of morbidity and mortality. We report herein a case of lye-induced esophageal perforation managed successfully by employing endoscopic T-tube...Full Text Available
BackgroundTrichloroethylene (TCE) may induce oxidative stress which generates free radicals and alters antioxidants or oxygen-free radical scavenging enzymes.MethodsTwenty...Full Text Available
The effects of dietary monosodium glutamate (MSG) on trans-fatty acid (TFA)-induced nonalcoholic fatty liver disease (NAFLD) are addressed in an animal model. We used Affymetrix microarray...Full Text Available
Systemic administration of lipopolysaccharide (LPS), which causes endotoxemia and systemic inflammation, has been reported to induce expression of the gene for type II inducible nitric oxide synthase...Full Text Available
mRNA is sequestered and turned over in cytoplasmic processing bodies (PBs), which are induced by various cellular stresses. Unexpectedly, in Saccharomyces cerevisiae, mutants of the...Full Text Available
Explants from flower stalks of Nicotiana tabacum L. were cultured on different cytokinins to induce flower bud formation. All cytokinins tested except zeatin and zeatin-riboside induced...Full Text Available
AbstractX-ray diffraction analysis of pressure-induced structural changes in the Aequorea yellow fluorescent protein Citrine reveals the structural basis for the continuous...Full Text Available
Rationale: Ventilator-induced lung injury (VILI) leads to an unacceptably high mortality. In this regard, the antiinflammatory properties of inhaled carbon monoxide (CO) may provide...Full Text Available
OBJECTIVES—To investigate the relation between different types of exposure to noise and a classic sign of noise induced hearing loss (NIHL), the audiometric notch. METHODS—The...Full Text Available
The Δ- and Λ-isomerism of octahedral metal complexes is employed as a source of chirality for inducing chiral nematic phases. By applying a wide range of chiral metal complexes as a...Full Text Available
Fatalities caused by parasitic infections often occur as a result of tissue injury that results from a form of host-cell death known as apoptosis. However, instead of being pathogenic, parasite-induced...Full Text Available
Wistar rats with streptozotocin-induced diabetes (STZ-diabetic rats), which is similar to human insulin-dependent diabetic mellitus (IDDM), were employed to investigate...Full Text Available
The aim of the present study was to evaluate the ameliorative potential of quercetin (QC) against paracetamol (PCM)-induced oxidative stress and biochemical alterations in mice blood. A total of 36...Full Text Available
BackgroundPeriodontal disease in diabetic patients presents higher severity and prevalence; and increased severity of ligature-induced periodontal disease has been verified in diabetic...Full Text Available
Hundreds of thousands of people worldwide live or work in close proximity to steel mills. Integrated steel production generates chemical pollution containing compounds that can induce genetic damage...Full Text Available
During sexual development, Neurospora crassa inactivates genes in duplicated DNA segments by a hypermutation process, repeat-induced point mutation (RIP). RIP introduces C:G to T:A...Full Text Available
Hepatocellular carcinoma (HCC) is a primary malignancy of the liver, which is closely related to hepatitis C and cirrhosis. The molecular mechanisms underlying the hepatocarcinogenesis induced by HCV...Full Text Available
Tiered response is a basic approach to emergency plans, including oil spill response (OSR). This paper delineates a huge set of accidental scenarios within a certain tier of response generated by a computer during risk assessment. Parameters such as the amount of oil spilled, duration of discharge and types of losses should be provided in OSR scenarios. Examples of applications include offshore installations, sub sea or onshore pipelines, and localized onshore facilities. The paper demonstrates how to use risk analysis results for delineating all likely spills into groups that need a specific tier response. The best world practices and Russian regulatory approaches were outlined and compared. Corresponding algorithms were developed and their application in pipelines was presented. The algorithm combines expert's skills and spill trajectory modeling with the net environmental benefit analysis ...
This paper presents some results of lightning induced over voltages for a typical high voltage transmission line configuration. The authors developed an elaborated electromagnetic coupling between the lightning channel and characteristics and the resulting induced overvoltage. The lightning current parameters, for local data, in order to determine the occurrence severity for high voltage transmission lines. (author)
Low temperature Nonphotochemical Hole Burning (NPHB) Spectroscopy of the dye rhodamine 800 (MF680) was applied for the purpose of discerning differences between cultured normal and carcinoma ovarian surface epithelial (OSE) cells. Both the cell lines were developed and characterized at the Mayo Clinic (Rochester, MN), with the normal cell line having been transfected with a strain of temperature sensitive Simian Virus 40 Large T Antigen (SV40) for the purpose of extending the life of the cell culture without inducing permanent changes in the characteristics of the cell line. The cationic lipophilic fluorophore rhodamine 800 preferentially locates in in situ mitochondria due to the high lipid composition of mitochondria and the generation of a large negative membrane potential (relative to the cellular cytoplasm) for oxidative phosphorylation. Results presented for NPHB of MF680 located in the cells show significant differences between the two cell lines. The ...
Low temperature Nonphotochemical Hole Burning (NPHB) Spectroscopy of the dye rhodamine 800 (MF680) was applied for the purpose of discerning differences between cultured normal and carcinoma ovarian surface epithelial (OSE) cells. Both the cell lines were developed and characterized at the Mayo Clinic (Rochester, MN), with the normal cell line having been transfected with a strain of temperature sensitive Simian Virus 40 Large T Antigen (SV40) for the purpose of extending the life of the cell culture without inducing permanent changes in the characteristics of the cell line. The cationic lipophilic fluorophore rhodamine 800 preferentially locates in in situ mitochondria due to the high lipid composition of mitochondria and the generation of a large negative membrane potential (relative to the cellular cytoplasm) for oxidative phosphorylation. Results presented for NPHB of MF680 located in the cells show significant differences between the two cell lines. The ...
p53 plays a critical role in tumor suppression. As a transcription factor, in response to stress signals, p53 regulates its target genes and initiates stress responses, including cell cycle arrest,...Full Text Available
The effects of response effort on safe behaviors (i.e., glove wearing, hand sanitizing, and electrical outlet replacement) exhibited by therapists at an autism treatment center were examined. Participants...Full Text Available
Separate groups of rats received 500 trials of lever-press training under autoshaping (food delivery followed 10-second lever presentations, or occurred immediately following a response); operant conditioning...Full Text Available
In vivo plasminogen responses to various stimuli were studied. Plasminogen-125I was prepared and used first for metabolic studies of plasminogen in control dogs. The average results were:...Full Text Available
The in vitro response of melatonin synthesis was assessed by incubation of individual whole pineal glands for 4 hr without or with different concentrations of isoproterenol in the medium. Pineals were taken either at the end of the 14-hr light phase (day)...
We have characterized the kinetic response of gene targets throughout the murine genome to transcriptional modulation by the glucocorticoid receptor (GR). In contrast to a model in which multiple genes...Full Text Available
Although management of warfarin is challenging for patients with chronic kidney disease (CKD), no prospective studies have compared response to warfarin among patients with minimal, moderate, and severe...Full Text Available
Gene arrays containing all currently known open reading frames of Bacillus subtilis were used to examine the general stress response of Bacillus. By proteomics, transcriptional...Full Text Available
Zinc is an essential trace metal ion for growth, but an excess of Zn is toxic and microorganisms express diverse resistance mechanisms. To understand global bacterial responses to excess Zn, we conducted...Full Text Available
Lumbricus terrestris (Annelid, Oligocheta) is capable of cellular- and humoral-specific reactions against natural antigens. Is this earthworm able to elaborate a response of antibody type against a...Full Text Available
BackgroundProfessionalism is a difficult construct to define in medical students but aspects of this concept may be important in predicting the risk of postgraduate misconduct. For...Full Text Available
BackgroundCells dynamically adapt their gene expression patterns in response to various stimuli. This response is orchestrated into a number of gene expression modules consisting...Full Text Available
Although skin is usually exposed during human exposures to ionizing radiation, there have been no thorough examinations of the transcriptional response of skin fibroblasts and keratinocytes...Full Text Available
Definition of the T-lymphocyte responses to dengue viruses should aid in the development of safe and effective vaccines and help to explain the pathophysiology of dengue hemorrhagic fever and dengue...Full Text Available
... gov Data Privacy, Emergency Response, Weather Prediction to Benefit from Information Technology ... detection, simulation and prediction of high-impact local weather, such as thunderstorms and ...
A compensatory response, viz. in vivo recovery from radiation damage to mitochondria, occurs in preclimacteric pear fruits (Pyrus communis L.) treated with ionizing...Full Text Available
The disordered eating response team developed a protocol for assessment and intervention for athletes who are identified as at risk for disordered eating. Team members included the team physician,...Full Text Available