Experimental study of ion-induced nucleation by radon decay

International Nuclear Information System (INIS)

He, F.; Hopke, P.K.

1993-01-01

In the environment, the presence of ions from natural radioactivity may increase the rate of new particle formation through ion-induced nucleation. A thermal diffusion cloud chamber (TDCC) has been built to experimentally study ion-induced nucleation where the ions are produced by gaseous radioactive sources. The critical supersaturation values and nucleation rates for methanol, ethanol, 1-propanol, and 1-butanol vapors on ions produced within the volume of the chamber by alpha decay of 222 Rn have been measured quantitatively at various radioactivity concentrations and supersaturations. The presence of ion tracks and the effect of an external electric field were also investigated. The alpha tracks and ion-induced nucleation formed by 222 Rn decay become visible at the critical supersaturation that is below the value needed for homogeneous nucleation. At this supersaturation, the nucleation rates increase substantially with increasing 222 Rn at low activity concentrations, but attain limiting values at higher concentrations. The experimental results indicate that the ionization by radon decay will promote ion-cluster formation and lower the free energy barriers. The formation of visible droplets is strongly dependent on the supersaturation. This study also confirms that the external electric field has a significant effect on the observed rates of nucleation

Experimental and Theoretical Investigation of Shock-Induced Reactions in Energetic Materials

Energy Technology Data Exchange (ETDEWEB)

Kay, Jeffrey J. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Park, Samuel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kohl, Ian Thomas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Knepper, Robert [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Farrow, Darcie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tappan, Alexander S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-09-01

In this work, shock-induced reactions in high explosives and their chemical mechanisms were investigated using state-of-the-art experimental and theoretical techniques. Experimentally, ultrafast shock interrogation (USI, an ultrafast interferometry technique) and ultrafast absorption spectroscopy were used to interrogate shock compression and initiation of reaction on the picosecond timescale. The experiments yielded important new data that appear to indicate reaction of high explosives on the timescale of tens of picoseconds in response to shock compression, potentially setting new upper limits on the timescale of reaction. Theoretically, chemical mechanisms of shock-induced reactions were investigated using density functional theory. The calculations generated important insights regarding the ability of several hypothesized mechanisms to account for shock-induced reactions in explosive materials. The results of this work constitute significant advances in our understanding of the fundamental chemical reaction mechanisms that control explosive sensitivity and initiation of detonation.

Cowhage-induced itch as an experimental model for pruritus. A comparative study with histamine-induced itch.

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Alexandru D P Papoiu

2011-03-01

Full Text Available Histamine is the prototypical pruritogen used in experimental itch induction. However, in most chronic pruritic diseases, itch is not predominantly mediated by histamine. Cowhage-induced itch, on the other hand, seems more characteristic of itch occurring in chronic pruritic diseases.We tested the validity of cowhage as an itch-inducing agent by contrasting it with the classical itch inducer, histamine, in healthy subjects and atopic dermatitis (AD patients. We also investigated whether there was a cumulative effect when both agents were combined.Fifteen healthy individuals and fifteen AD patients were recruited. Experimental itch induction was performed in eczema-free areas on the volar aspects of the forearm, using different itch inducers: histamine, cowhage and their combination thereof. Itch intensity was assessed continuously for 5.5 minutes after stimulus application using a computer-assisted visual analogue scale (COVAS.In both healthy and AD subjects, the mean and peak intensity of itch were higher after the application of cowhage compared to histamine, and were higher after the combined application of cowhage and histamine, compared to histamine alone (p<0.0001 in all cases. Itch intensity ratings were not significantly different between healthy and AD subjects for the same itch inducer used; however AD subjects exhibited a prolonged itch response in comparison to healthy subjects (p<0.001.Cowhage induced a more intense itch sensation compared to histamine. Cowhage was the dominant factor in itch perception when both pathways were stimulated in the same time. Cowhage-induced itch is a suitable model for the study of itch in AD and other chronic pruritic diseases, and it can serve as a new model for testing antipruritic drugs in humans.

Protective effects of ebselen on sodium-selenite-induced experimental cataract in rats.

Science.gov (United States)

Aydemir, Orhan; Güler, Mete; Kaya, Mehmet Kaan; Deniz, Nurettin; Üstündağ, Bilal

2012-12-01

To determine whether ebselen has a protective effect or antioxidative potential in a sodium-selenite-induced experimental cataract model. Fırat University, Elazığ, Turkey. Experimental study. Twenty-one Sprague-Dawley rat pups were randomly divided into a control group, a sodium-selenite-induced-cataract group, and an ebselen-treated group; each group contained 7 rat pups. Rats in the control group received dimethyl sulfoxide (DMSO) intraperitoneally only and rats in the sodium-selenite-induced-cataract group received 30 nmol/g body weight sodium selenite subcutaneously and DMSO intraperitoneally 10 days postpartum. Rats in the ebselen group received 30 nmol/g body weight sodium selenite subcutaneously 10 days postpartum and were treated with 5 mg/kg body weight ebselen once a day for 4 consecutive days. Cataract development was assessed weekly for 3 weeks by slitlamp examination and graded using a scale. Reduced glutathione (GSH), total nitrite, and malondialdehyde (MDA) levels in lens supernatants were measured at the end of 3 weeks. In the control group, all lenses were clear. In the ebselen-treated group, the mean cataract stage was significantly lower than in the sodium-selenite-induced-cataract group (P = .022). The GSH levels were significantly lower in the sodium-selenite-induced-cataract group than in the control and ebselen groups (P ebselen group than in the sodium-selenite-induced-cataract group (P ebselen group (P = .001). Ebselen had a protective effect on cataract development in a sodium-selenite-induced experimental model. The protective effect of ebselen appears to be due to inhibition of oxidative stress. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Neuroendocrine mechanisms of development of experimental hyperandrogen-induced anovulation.

Science.gov (United States)

Reznikov, A G; Sinitsyn, P V; Tarasenko, L V; Polyakova, L I

2003-10-01

An experimental model of hyperandrogen-induced anovulatory infertility (s.c. implantation of Silastic capsules containing testosterone into adult female rats) was used to study morphological, hormonal, and biochemical measures characterizing the state of the hypothalamo-hypophyseal-ovarian system. Impairments in functional androgen metabolism in the hypothalamus were seen, with decreases in the Luliberin sensitivity of the hypophysis, changes in the structure of estral cycles, and morphological changes in the ovaries; these findings are evidence for neuroendocrine disturbances in the control of ovulation. Flutamide, an experimental antiandrogen, led to partial normalization of the hormonal, biochemical, and morphological characteristics, as well as to recovery of fertility in females with anovulatory infertility.

Experimental and numerical analysis for magnetically induced vibrations of conducting structure

International Nuclear Information System (INIS)

Nishio, Satoshi; Nakahira, Masataka; Miura, H.; Isono, A.

1993-01-01

The coupling effect between the electromagnetic field and mechanical response of a conducting structure is of importance in magnetic fusion devices as tokamak machine. The electromagnetically induced motion of the structure due to the Lorentz force induces additional eddy currents and further modifies the dynamic characteristics of the system. This paper is concerned with numerical modeling of the dynamic field-structure interaction and its verification by experimental tests. Here, a finite element numerical model for mechanical deformation and a wiregrid numerical model for eddy currents are employed for non-ferrous and elastic conductors. A computer code has been developed for 3-D thin shell structure. Experimental tests for the code verification were carried out by using a rectangular thin copper plate. Three kinds of the plate supporting systems, i.e., a cantilever system, a fixed both ends system and a simply supported ends system were investigated. A good agreement between the numerical and experimental results was obtained. Therefore, the computer code developed here is available for analyzing the electromagnetomechanical behavior of the plasma facing components of the tokamak device. (author)

Surfactant induced flows in thin liquid films : an experimental study

NARCIS (Netherlands)

Sinz, D.K.N.

2012-01-01

The topic of the experimental work summarized in my thesis is the flow in thin liquid films induced by non-uniformly distributed surfactants. The flow dynamics as a consequence of the deposition of a droplet of an insoluble surfactant onto a thin liquid film covering a solid substrate where

Anti-glaucoma potential of Heliotropium indicum Linn in experimentally-induced glaucoma

OpenAIRE

Kyei, Samuel; Koffuor, George Asumeng; Ramkissoon, Paul; Owusu-Afriyie, Osei

2015-01-01

Background Heliotropium indicum is used as a traditional remedy for hypertension in Ghana. The aim of the study was to evaluate the anti-glaucoma potential of an aqueous whole plant extract of H. indicum to manage experimentally-induced glaucoma. Methods The percentage change in intraocular pressure (IOP), after inducing acute glaucoma (15 mLkg?1 of 5?% dextrose, i.v.), in New Zealand White rabbits pretreated with Heliotropium indicum aqueous extract (HIE) (30?300 mgkg?1), acetazolamide (5 mg...

Experimental diabetes induces structural, inflammatory and vascular changes of Achilles tendons.

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Rodrigo R de Oliveira

Full Text Available This study aims to demonstrate how the state of chronic hyperglycemia from experimental Diabetes Mellitus can influence the homeostatic imbalance of tendons and, consequently, lead to the characteristics of tendinopathy. Twenty animals were randomly divided into two experimental groups: control group, consisting of healthy rats and diabetic group constituted by rats induced to Diabetes Mellitus I. After twenty-four days of the induction of Diabetes type I, the Achilles tendon were removed for morphological evaluation, cellularity, number and cross-sectional area of blood vessel, immunohistochemistry for Collagen type I, VEGF and NF-κB nuclear localization sequence (NLS and nitrate and nitrite level. The Achilles tendon thickness (µm/100g of diabetic animals was significantly increased and, similarly, an increase was observed in the density of fibrocytes and mast cells in the tendons of the diabetic group. The average number of blood vessels per field, in peritendinous tissue, was statistically higher in the diabetic group 3.39 (2.98 vessels/field when compared to the control group 0.89 (1.68 vessels/field p = 0.001 and in the intratendinous region, it was observed that blood vessels were extremely rare in the control group 0.035 (0.18 vessels/field and were often present in the tendons of the diabetic group 0.89 (0.99 vessels/field. The immunohistochemistry analysis identified higher density of type 1 collagen and increased expression of VEGF as well as increased immunostaining for NFκB p50 NLS in the nucleus in Achilles tendon of the diabetic group when compared to the control group. Higher levels of nitrite/nitrate were observed in the experimental group induced to diabetes. We conclude that experimental DM induces notable structural, inflammatory and vascular changes in the Achilles tendon which are compatible with the process of chronic tendinopathy.

Experimental Branch Retinal Vein Occlusion Induces Upstream Pericyte Loss and Vascular Destabilization.

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Elisa Dominguez

Full Text Available Branch retinal vein occlusion (BRVO leads to extensive vascular remodeling and is important cause of visual impairment. Although the vascular morphological changes following experimental vein occlusion have been described in a variety of models using angiography, the underlying cellular events are ill defined.We here show that laser-induced experimental BRVO in mice leads to a wave of TUNEL-positive endothelial cell (EC apoptosis in the upstream vascular network associated with a transient edema and hemorrhages. Subsequently, we observe an induction of EC proliferation within the dilated vein and capillaries, detected by EdU incorporation, and the edema resolves. However, the pericytes of the upstream capillaries are severely reduced, which was associated with continuing EC apoptosis and proliferation. The vascular remodeling was associated with increased expression of TGFβ, TSP-1, but also FGF2 expression. Exposure of the experimental animals to hypoxia, when pericyte (PC dropout had occurred, led to a dramatic increase in endothelial cell proliferation, confirming the vascular instability induced by the experimental BRVO.Experimental BRVO leads to acute endothelial cells apoptosis and increased permeability. Subsequently the upstream vascular network remains destabilized, characterized by pericyte dropout, un-physiologically high endothelial cells turnover and sensitivity to hypoxia. These early changes might pave the way for capillary loss and subsequent chronic ischemia and edema that characterize the late stage disease.

Corticostriatal Plastic Changes in Experimental L-DOPA-Induced Dyskinesia

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Veronica Ghiglieri

2012-01-01

Full Text Available In Parkinson’s disease (PD, alteration of dopamine- (DA- dependent striatal functions and pulsatile stimulation of DA receptors caused by the discontinuous administration of levodopa (L-DOPA lead to a complex cascade of events affecting the postsynaptic striatal neurons that might account for the appearance of L-DOPA-induced dyskinesia (LID. Experimental models of LID have been widely used and extensively characterized in rodents and electrophysiological studies provided remarkable insights into the inner mechanisms underlying L-DOPA-induced corticostriatal plastic changes. Here we provide an overview of recent findings that represent a further step into the comprehension of mechanisms underlying maladaptive changes of basal ganglia functions in response to L-DOPA and associated to development of LID.

Experimentally induced cam impingement in the sheep hip.

Science.gov (United States)

Siebenrock, Klaus A; Fiechter, Ruth; Tannast, Moritz; Mamisch, Tallal C; von Rechenberg, Brigitte

2013-04-01

Sheep hips have a natural non-spherical femoral head similar to a cam-type deformity in human beings. By performing an intertrochanteric varus osteotomy, cam-type femoro-acetabular impingement (FAI) during flexion can be created. We tested the hypotheses that macroscopic lesions of the articular cartilage and an increased Mankin score (MS) can be reproduced by an experimentally induced cam-type FAI in this ovine in vivo model. Furthermore, we hypothesized that the MS increases with longer ambulatory periods. Sixteen sheep underwent unilateral intertrochanteric varus osteotomy of the hip with the non-operated hip as a control. Four sheep were sacrificed after 14, 22, 30, and 38-weeks postoperatively. We evaluated macroscopic chondrolabral alterations, and recorded the MS, based on histochemical staining, for each ambulatory period. A significantly higher prevalence of macroscopic chondrolabral lesions was found in the impingement zone of the operated hips. The MS was significantly higher in the acetabular/femoral cartilage of the operated hips. Furthermore, these scores increased as the length of the ambulatory period increased. Cam-type FAI can be induced in an ovine in vivo model. Localized chondrolabral degeneration of the hip, similar to that seen in humans (Tannast et al., Clin Orthop Relat Res 2008; 466: 273-280; Beck et al., J Bone Joint Surg Br 2005; 87: 1012-1018), can be reproduced. This experimental sheep model can be used to study cam-type FAI. Copyright © 2012 Orthopaedic Research Society.

Numerical and experimental investigation of the self-inducing turbine aeration capacity

International Nuclear Information System (INIS)

Achouri, Ryma; Dhaouadi, Hatem; Mhiri, Hatem; Bournot, Philippe

2014-01-01

Highlights: • Numerical and experimental study of k L a coefficient of a self-inducing turbine. • Validation of experimental results. • Numerical study of k L a variation with the variation of impeller submersion and blade inclination. • Numerical study of the flow field and hydrodynamic parameters. - Abstract: Self-inducing turbines are a model of mixers that ensure the aeration of a fluid field without using a sparger and a surface aerator. Nevertheless, this type of turbines remain quite complicated in terms of behavior of the fluid within the tank, and its actual aeration capacity varies depending on the type of turbine used. The studied turbine is self-inducing and made of three blades and each blade contains five holes. In this work, we evaluated experimentally – using the technique of dynamic oxygenation and deoxygenating – the aeration capacity of our impeller by calculating the volumetric mass transfer coefficient k L a for various submergences and various inclination angles of the blade. This work was then validated by a numerical modeling using the commercial code Fluent, and the flow within the tank as well as the evolution of the hydrodynamic parameters was also studied. The simulation is steady state with a VOF multiphase model and the realizable k–ε turbulence model. We finally concluded that k L a decreases with the increase of the inclination angle and with the increase of the submergence of our turbine. We could also study the hydrodynamic parameters of the flow such as the power number, the aeration number and the shear rate

Activity and milk compositional changes following experimentally induced Streptococcus uberis bovine mastitis.

Science.gov (United States)

Kester, H J; Sorter, D E; Hogan, J S

2015-02-01

Milk constituents and physical activity of cows experimentally infected with Streptococcus uberis mastitis were compared with those of uninfected cows. Twelve late-lactation Holsteins cows were paired based on milk production and parity. One cow in each pair was experimentally infected in the right front mammary gland with Strep. uberis. The remaining cow in each pair served as an uninfected control. Real-time analyses of milk constituents provided fat, protein, and lactose percentages at each milking. Pedometers were placed on the left front leg of all cows and activity was measured. Intramammary infections with Strep. uberis reduced milk yield in experimental cows by approximately 1.6kg/d in the first week after challenge compared with control cows. Lactose percentage in milk was reduced on d 3, 4, 5, and 6 after challenge in treatment cows compared with controls. Percentages of fat and protein in milk did not differ between infected and uninfected cows the week after infections were induced. Total steps per day were reduced and minutes resting per day were increased the week after experimental challenge in infected cows compared with control cows. The number of resting bouts did not differ between infected and uninfected cows. Changes in percentage of lactose in milk and animal activity caused by experimentally induced Strep. uberis mastitis were detected by the automated milk analyzer and pedometer systems. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Cardioprotective effect of amlodipine in oxidative stress induced by experimental myocardial infarction in rats

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Sudhira Begum

2007-12-01

Full Text Available The present study investigated whether the administration of amlodipine ameliorates oxidative stress induced by experimental myocardial infarction in rats. Adrenaline was administered and myocardial damage was evaluated biochemically [significantly increased serum aspertate aminotransferase (AST, lactate dehydrogenase (LDH and malondialdehyde (MDA levels of myocardial tissue] and histologically (morphological changes of myocardium. Amlodipine was administered as pretreatment for 14 days in adrenaline treated rats. Statistically significant amelioration in all the biochemical parameters supported by significantly improved myocardial morphology was observed in amlodipine pretreatment. It was concluded that amlodipine afforded cardioprotection by reducing oxidative stress induced in experimental myocardial infarction of catecholamine assault.

Immediate effects of chocolate on experimentally induced mood states.

Science.gov (United States)

Macht, Michael; Mueller, Jochen

2007-11-01

In this work two hypotheses were tested: (1) that eating a piece of chocolate immediately affects negative, but not positive or neutral mood, and (2) that this effect is due to palatability. Experiment 1 (48 normal-weight and healthy women and men) examined the effects of eating a piece of chocolate and drinking water on negative, positive and neutral mood states induced by film clips. Eating chocolate reduced negative mood compared to drinking water, whereas no or only marginal effects were found on neutral and positive moods. Experiment 2 (113 normal-weight and healthy women and men) compared effects of eating palatable and unpalatable chocolate on negative mood, and examined the duration of chocolate-induced mood change. Negative mood was improved after eating palatable chocolate as compared to unpalatable chocolate or nothing. This effect was short lived, i.e., it disappeared after 3 min. In both experiments, chocolate-induced mood improvement was associated with emotional eating. The present studies demonstrate that eating a small amount of sweet food improves an experimentally induced negative mood state immediately and selectively and that this effect of chocolate is due to palatability. It is hypothesized that immediate mood effects of palatable food contribute to the habit of eating to cope with stress.

Local and Systemic Inflammatory Responses to Experimentally Induced Gingivitis

Science.gov (United States)

Leishman, Shaneen J.; Seymour, Gregory J.; Ford, Pauline J.

2013-01-01

This study profiled the local and systemic inflammatory responses to experimentally induced gingivitis. Eight females participated in a 21-day experimental gingivitis model followed by a 14-day resolution phase. Bleeding on probing and plaque index scores were assessed before, during, and after resolution of gingival inflammation, and samples of saliva, GCF, and plasma were collected. Samples were assessed for biomarkers of inflammation using the BioPlex platform and ELISA. There were no significant changes in GCF levels of cytokines during the experimental phase; however, individual variability in cytokine profiles was noted. During resolution, mean GCF levels of IL-2, IL-6, and TNF-α decreased and were significantly lower than baseline levels (P = 0.003, P = 0.025, and P = 0.007, resp.). Furthermore, changes in GCF levels of IL-2, IL-6, and TNF-α during resolution correlated with changes in plaque index scores (r = 0.88, P = 0.004; r = 0.72, P = 0.042; r = 0.79, P = 0.019, resp.). Plasma levels of sICAM-1 increased significantly during the experimental phase (P = 0.002) and remained elevated and significantly higher than baseline levels during resolution (P gingivitis adds to the systemic inflammatory burden of an individual. PMID:24227893

Tramadol Induced Adrenal Insufficiency: Histological, Immunohistochemical, Ultrastructural, and Biochemical Genetic Experimental Study

OpenAIRE

Abdelaleem, Shereen Abdelhakim; Hassan, Osama A.; Ahmed, Rasha F.; Zenhom, Nagwa M.; Rifaai, Rehab A.; El-Tahawy, Nashwa F.

2017-01-01

Tramadol is a synthetic, centrally acting analgesic. It is the most consumed narcotic drug that is prescribed in the world. Tramadol abuse has dramatically increased in Egypt. Long term use of tramadol can induce endocrinopathy. So, the aim of this study was to analyze the adrenal insufficiency induced by long term use of tramadol in experimental animals and also to assess its withdrawal effects through histopathological and biochemical genetic study. Forty male albino rats were used in this ...

Nutrient Induced Type 2 and Chemical Induced Type 1 Experimental Diabetes Differently Modulate Gastric GLP-1 Receptor Expression

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Olga Bloch

2015-01-01

Full Text Available T2DM patients demonstrate reduced GLP-1 receptor (GLP-1R expression in their gastric glands. Whether induced T2DM and T1DM differently affect the gastric GLP-1R expression is not known. This study assessed extrapancreatic GLP-1R system in glandular stomach of rodents with different types of experimental diabetes. T2DM and T1DM were induced in Psammomys obesus (PO by high-energy (HE diet and by streptozotocin (STZ in Sprague Dawly (SD rats, respectively. GLP-1R expression was determined in glandular stomach by RT PCR and immunohistomorphological analysis. The mRNA expression and cellular association of the GLP-1R in principal glands were similar in control PO and SD rats. However, nutrient and chemical induced diabetes resulted in opposite alterations of glandular GLP-1R expression. Diabetic PO demonstrated increased GLP-1R mRNA expression, intensity of cellular GLP-1R immunostaining, and frequency of GLP-1R positive cells in the neck area of principal glands compared with controls. In contrast, SD diabetic rats demonstrated decreased GLP-1 mRNA, cellular GLP-1R immunoreactivity, and frequency of GLP-1R immunoreactive cells in the neck area compared with controls. In conclusion, nutrient and chemical induced experimental diabetes result in distinct opposite alterations of GLP-1R expression in glandular stomach. These results suggest that induced T1DM and T2DM may differently modulate GLP-1R system in enteropancreatic axis.

Patterns of experimentally induced pain in pericranial muscles

DEFF Research Database (Denmark)

Schmidt-Hansen, Peter Thede; Svensson, Peter; Jensen, Troels Staehelin

2006-01-01

into the masseter muscle (anova: P pain areas (anova: P cervically innervated muscles had significantly different patterns of spread and referral of pain according to trigeminally vs....... cervically innervated dermatomes (P pain patterns and pain sensitivity in different craniofacial muscles in healthy volunteers, which may be of importance for further research on different craniofacial pain conditions.......Nociceptive mechanisms in the craniofacial muscle tissue are poorly understood. The pain pattern in individual pericranial muscles has not been described before. Experimental muscle pain was induced by standardized infusions of 0.2 ml 1 m hypertonic saline into six craniofacial muscles (masseter...

Transformation induced plasticity in maraging steel: an experimental study

International Nuclear Information System (INIS)

Nagayama, K.; Kitajima, Y.; Kigami, S.; Tanaka, K.

2000-01-01

The deformation behavior of a maraging TRIP (transformation induced plasticity) steel (MAVAL X12) is studied experimentally under a constant load. The existence of the back stress in the axial direction is directly proved by investigating the dilatation curves. Martensite-start lines are given under tensile, compressive and shear stresses. The evolution of TRIP strain and the maximum TRIP strain are determined. The alloy response during isothermal tensile test is explained in terms of influences both by the composite and transformation. (orig.)

Phosphorus-31 magnetic resonance spectroscopy of experimentally induced arthritis in rats

International Nuclear Information System (INIS)

Blatter, D.D.

1987-01-01

Phosphorus-31 magnetic resonance spectroscopy (MRS) of the hind paws of rats was performed at 1.5 Tesla before and during the course of an experimentally-induced inflammatory arthritis. Arthritis was induced by daily subcutaneous administration of 6-sulfanilamidoindazole, an antibacterial sulfa known to produce an acute, self-limited arthritis and periarthritis in the hind paws of rats. Phosphorus-31 spectra obtained after the development of clinical arthritis showed a significant (p 31 P MRS may permit evaluation of the severity of an inflammatory arthritis with greater accuracy than the bony changes definable by plain roentgenograms. (orig.)

Modeling Chemotherapy-Induced Hair Loss: From Experimental Propositions toward Clinical Reality.

Science.gov (United States)

Botchkarev, Vladimir A; Sharov, Andrey A

2016-03-01

Chemotherapy-induced hair loss is one of the most devastating side effects of cancer treatment. To study the effects of chemotherapeutic agents on the hair follicle, a number of experimental models have been proposed. Yoon et al. report that transplantation of human scalp hair follicles onto chemotherapy-treated immunodeficient mice serves as an excellent in vivo model for chemotherapy-induced hair loss. Yoon et al. demonstrate that (i) the response of human hair follicles grafted onto immunodeficient mice to cyclophosphamide resembles the key features of the chemotherapy-induced hair loss seen in patients with cancer and (ii) this human in vivo model for chemotherapy-induced hair loss is closer to clinical reality than to any earlier models. Undoubtedly, this model will serve as a valuable tool for analyses of the mechanisms that underlie this devastating side effect of anti-cancer therapy. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Paradoxical effects of rapamycin on experimental house dust mite-induced asthma.

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Karin Fredriksson

Full Text Available The mammalian target of rapamycin (mTOR modulates immune responses and cellular proliferation. The objective of this study was to assess whether inhibition of mTOR with rapamycin modifies disease severity in two experimental murine models of house dust mite (HDM-induced asthma. In an induction model, rapamycin was administered to BALB/c mice coincident with nasal HDM challenges for 3 weeks. In a treatment model, nasal HDM challenges were performed for 6 weeks and rapamycin treatment was administered during weeks 4 through 6. In the induction model, rapamycin significantly attenuated airway inflammation, airway hyperreactivity (AHR and goblet cell hyperplasia. In contrast, treatment of established HDM-induced asthma with rapamycin exacerbated AHR and airway inflammation, whereas goblet cell hyperplasia was not modified. Phosphorylation of the S6 ribosomal protein, which is downstream of mTORC1, was increased after 3 weeks, but not 6 weeks of HDM-challenge. Rapamycin reduced S6 phosphorylation in HDM-challenged mice in both the induction and treatment models. Thus, the paradoxical effects of rapamycin on asthma severity paralleled the activation of mTOR signaling. Lastly, mediastinal lymph node re-stimulation experiments showed that treatment of rapamycin-naive T cells with ex vivo rapamycin decreased antigen-specific Th2 cytokine production, whereas prior exposure to in vivo rapamycin rendered T cells refractory to the suppressive effects of ex vivo rapamycin. We conclude that rapamycin had paradoxical effects on the pathogenesis of experimental HDM-induced asthma. Thus, consistent with the context-dependent effects of rapamycin on inflammation, the timing of mTOR inhibition may be an important determinant of efficacy and toxicity in HDM-induced asthma.

Experimental studies of the propagation of electrostatic ion perturbations by time-resolved laser-induced fluorescence

International Nuclear Information System (INIS)

Bachet, G.; Skiff, F.; Doveil, F.; Stern, R.A.

2001-01-01

Effects induced by the propagation of several kinds of electrostatic perturbation in a low-density collisionless argon plasma are observed with space, time, and velocity-resolved laser-induced fluorescence (LIF). The propagation of strong self-organized ion structures is observed and the associated electric field is determined. Snap shots of the ion phase space with a time resolution of 2 μs can be reconstructed from the experimental data. All the terms of the kinetic equation can also be determined from the data. A one-dimensional (1D) numerical simulation reproduces qualitatively the experimentally observed ion phase space behavior

Functional magnetic resonances imaging of psychological functions with experimentally induced emotion

International Nuclear Information System (INIS)

Grodd, W.; Schneider, F.; Klose, U.; Naegele, T.

1995-01-01

In this study a T 2 * FLASH sequence (TR 240 ms, TE 60 ms, slice thickness 4 mm, α=40 , matrix 64x128) was used to investigate changes in signal intensity within the temporal lobe and the amygdala during experimentally induced emotions. Visual stimuli of happy [sad] facial portraits were presented to volunteers to induce changes in the subjects' mood while lying in the tomograph. In agreement with a previous PET study, a significant increase in signal intensity in the left amygdala was found during induction of a sad mood, while no comparable effect was visible during induction of a happy mood. (orig.) [de

Oxidative stress in immature brain following experimentally-induced seizures

Czech Academy of Sciences Publication Activity Database

Folbergrová, Jaroslava

2013-01-01

Roč. 62, Suppl.1 (2013), S39-S48 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GA309/05/2015; GA ČR(CZ) GA309/08/0292; GA ČR(CZ) GAP303/10/0999; GA ČR(CZ) GAP302/10/0971; GA MŠk(CZ) LL1204 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : immature rats * experimentally-induced seizures * oxidative stress * mitochondrial dysfunction * antioxidant defense Subject RIV: FH - Neurology Impact factor: 1.487, year: 2013

Experimental gingivitis induces systemic inflammatory markers in young healthy individuals: a single-subject interventional study.

Science.gov (United States)

Eberhard, Jörg; Grote, Karsten; Luchtefeld, Maren; Heuer, Wieland; Schuett, Harald; Divchev, Dimitar; Scherer, Ralph; Schmitz-Streit, Ruth; Langfeldt, Daniela; Stumpp, Nico; Staufenbiel, Ingmar; Schieffer, Bernhard; Stiesch, Meike

2013-01-01

We here investigated whether experimental gingivitis enhances systemic markers of inflammation which are also known as surrogate markers of atherosclerotic plaque development. Gingivitis is a low-level oral infection induced by bacterial deposits with a high prevalence within Western populations. A potential link between the more severe oral disease periodontitis and cardiovascular disease has already been shown. 37 non-smoking young volunteers with no inflammatory disease or any cardiovascular risk factors participated in this single-subject interventional study with an intra-individual control. Intentionally experimental oral inflammation was induced by the interruption of oral hygiene for 21 days, followed by a 21-days resolving phase after reinitiation of oral hygiene. Primary outcome measures at baseline, day 21 and 42 were concentrations of hsCRP, IL-6, and MCP-1, as well as adhesion capacity and oxLDL uptake of isolated blood monocytes. The partial cessation of oral hygiene procedures was followed by the significant increase of gingival bleeding (34.0%, Pgingivitis. Bacterial-induced gingival low-level inflammation induced a systemic increase in inflammatory markers. Dental hygiene almost completely reversed this experimental inflammatory process, suggesting that appropriate dental prophylaxis may also limit systemic markers of inflammation in subjects with natural gingivitis. International Clinical Trials Register Platform of the World Health Organization, registry number: DRKS00003366, URL: http://apps.who.int/trialsearch/Default.aspx.

Comparative experimental study of cancer induced by ionizing radiations or by chemical carcinogens

International Nuclear Information System (INIS)

Lafuma, J.

1983-01-01

Animal experiments have contributed to specify a number of parameters used in setting human safety limits for ionizing radiation. In the same way, comparisons have been made between cancers induced in man and in animals in well-defined conditions. In order to use the same experimental data for chemical carcinogens, the mechanisms of carcinogenesis should be the same, i.e. additivity of responses instead of synergy of effects, which requires the development of a new experimental method [fr

Foraminiferal survival after long term experimentally induced anoxia

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Langlet, D.; Geslin, E.; Baal, C.; Metzger, E.; Lejzerowicz, F.; Riedel, B.; Zuschin, M.; Pawlowski, J.; Stachowitsch, M.; Jorissen, F. J.

2013-06-01

Anoxia has been successfully induced in four benthic chambers installed on the Northern Adriatic seafloor from 1 week to 10 months. To accurately determine whether benthic foraminifera can survive experimentally induced prolonged anoxia, the CellTrackerGreen method has been applied. Numerous individuals have been found living at all sampling times and at all sampling depths, showing that benthic foraminifera can survive up to 10 months of anoxia with co-occurring hydrogen sulphides. However, foraminiferal standing stocks decrease with sampling time in an irregular way. A large difference in standing stock between two cores samples in initial conditions indicates the presence of a large spatial heterogeneity of the foraminiferal faunas. An unexpected increase in standing stocks after 1 month is tentatively interpreted as a reaction to increased food availability due to the massive mortality of infaunal macrofaunal organisms. After this, standing stocks decrease again in a core sampled after 2 months of anoxia, to attain a minimum in the cores sampled after 10 months. We speculate that the trend of overall decrease of standing stocks is not due to the adverse effects of anoxia and hydrogen sulphides, but rather due to a continuous diminution of labile organic matter.

Ultraviolet radiation-induced carcinogenesis: mechanisms and experimental models

International Nuclear Information System (INIS)

Ramasamy, Karthikeyan; Shanmugam, Mohana; Balupillai, Agilan; Govindhasamy, Kanimozhi; Gunaseelan, Srithar; Muthusamy, Ganesan; Robert, Beualah Mary; Nagarajan, Rajendra Prasad

2017-01-01

Ultraviolet radiation (UVR) is a very prominent environmental toxic agent. UVR has been implicated in the initiation and progression of photocarcinogenesis. UVR exposure elicits numerous cellular and molecular events which include the generation of inflammatory mediators, DNA damage, epigenetic modifications, and oxidative damages mediated activation of signaling pathways. UVR-initiated signal transduction pathways are believed to be responsible for tumor promotion effects. UVR-induced carcinogenic mechanism has been well studied using various animal and cellular models. Human skin-derived dermal fibroblasts, epidermal keratinocytes, and melanocytes served as excellent cellular model systems for the understanding of UVR-mediated carcinogenic events. Apart from this, scientists developed reconstituted three-dimensional normal human skin equivalent models for the study of UVR signaling pathways. Moreover, hairless mice such as SKH-1, devoid of Hr gene, served as a valuable model for experimental carcinogenesis. Scientists have also used transgenic mice and dorsal portion shaved Swiss albino mice for UVR carcinogenesis studies. In this review, we have discussed the current progress in the study on ultraviolet B (UVB)-mediated carcinogenesis and outlined appropriate experimental models for both ultraviolet A- and UVB-mediated carcinogenesis. (author)

Proximally evoked soleus H-reflex to S1 nerve root stimulation in sensory neuronopathies (ganglionopathies).

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Zhu, Dong-Qing; Zhu, Yu; Qiao, Kai; Zheng, Chao-Jun; Bradley, Scott; Weber, Robert; Chen, Xiang-Jun

2013-11-01

Sensory neuronopathy (SNN) mimics distal sensory axonopathy. The conventional H-reflex elicited by tibial nerve stimulation (tibial H-reflex) is usually abnormal in both conditions. We evaluated the proximally evoked soleus H-reflex in response to S1 nerve root stimulation (S1 foramen H-reflex) in SNN. Eleven patients with SNN and 6 with distal sensory axonopathy were studied. Tibial and S1 foramen H-reflexes were performed bilaterally in each patient. Tibial and S1 foramen H-reflexes were absent bilaterally in all patients with SNN. In the patients with distal sensory axonopathy, tibial H-reflexes were absent in 4 and demonstrated prolonged latencies in 2, but S1 foramen H-reflexes were normal. Characteristic absence of the H-reflex after both proximal and distal stimulation reflects primary loss of dorsal root ganglion (DRG) neurons and the distinct non-length-dependent impairment of sensory nerve fibers in SNN. Copyright © 2013 Wiley Periodicals, Inc.

Effect of Manilkara hexandra (Roxb.) Dubard against experimentally-induced gastric ulcers.

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Shah, Mamta B; Goswami, S S; Santani, D D

2004-10-01

Effects of the flavonoid rich fraction of the stem bark of Manilkara hexandra (Roxb.) Dubard, have been studied on ethanol, ethanol-indomethacin and pylorus ligated gastric ulcers in experimental animals. Oral administration of the ethyl acetate extract (extract A3) inhibited the formation of gastric lesions induced by ethanol in a dose dependent manner. The protective effect of extract A3 against ethanol induced gastric lesions was not abolished by pretreatment with indomethacin (10 mg kg(-1)). Further, extract A3 inhibited increase in vascular permeability due to ethanol administration. Extent of lipid peroxidation was significantly reduced in animals treated with extract. Extract A3 also inhibited the formation of gastric ulcers induced by pylorus ligation, when administered both orally and intraperitoneally. Moreover, pretreatment with extract A3 increased mucus production and glycoprotein content, which was evident from the rise in mucin activity and TC: PR ratio. Copyright 2004 John Wiley & Sons, Ltd.

Experimental arthritis induced by a clinical Mycoplasma fermentans isolate

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Giono Silvia

2002-06-01

Full Text Available Abstract Background Mycoplasma fermentans has been associated with rheumatoid arthritis. Recently, it was detected in the joints and blood of patients with rheumatoid arthritis, but it is not clear yet how the bacteria enter the body and reach the joints. The purpose of this study was to determine the ability of M. fermentans to induce experimental arthritis in rabbits following inoculation of the bacteria in the trachea and knee joints. Methods P-140 and PG-18 strains were each injected in the knee joints of 14 rabbits in order to evaluate and compare their arthritogenicity. P-140 was also injected in the trachea of 14 rabbits in order to test the ability of the bacteria to reach the joints and induce arthritis. Results M. fermentans produced an acute arthritis in rabbits. Joint swelling appeared first in rabbits injected with P-140, which caused a more severe arthritis than PG-18. Both strains were able to migrate to the uninoculated knee joints and they were detected viable in the joints all along the duration of the experiment. Changes in the synovial tissue were more severe by the end of the experiment and characterized by the infiltration of neutrophils and substitution of adipose tissue by connective tissue. Rabbits intracheally injected with P-140 showed induced arthritis and the bacteria could be isolated from lungs, blood, heart, kidney, spleen, brain and joints. Conclusion M. fermentans induced arthritis regardless of the inoculation route. These findings may help explain why mycoplasmas are commonly isolated from the joints of rheumatic patients.

Effects of experimentally-induced maternal hypothyroidism on crucial offspring rat brain enzyme activities.

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Koromilas, Christos; Liapi, Charis; Zarros, Apostolos; Stolakis, Vasileios; Tsagianni, Anastasia; Skandali, Nikolina; Al-Humadi, Hussam; Tsakiris, Stylianos

2014-06-01

Hypothyroidism is known to exert significant structural and functional changes to the developing central nervous system, and can lead to the establishment of serious mental retardation and neurological problems. The aim of the present study was to shed more light on the effects of gestational and/or lactational maternal exposure to propylthiouracil-induced experimental hypothyroidism on crucial brain enzyme activities of Wistar rat offspring, at two time-points of their lives: at birth (day-1) and at 21 days of age (end of lactation). Under all studied experimental conditions, offspring brain acetylcholinesterase (AChE) activity was found to be significantly decreased due to maternal hypothyroidism, in contrast to the two studied adenosinetriphosphatase (Na(+),K(+)-ATPase and Mg(2+)-ATPase) activities that were only found to be significantly altered right after birth (increased and decreased, respectively, following an exposure to gestational maternal hypothyroidism) and were restored to control levels by the end of lactation. As our findings regarding the pattern of effects that maternal hypothyroidism has on the above-mentioned crucial offspring brain enzyme activities are compared to those reported in the literature, several differences are revealed that could be attributed to both the mode of the experimental simulation approach followed as well as to the time-frames examined. These findings could provide the basis for a debate on the need of a more consistent experimental approach to hypothyroidism during neurodevelopment as well as for a further evaluation of the herein presented and discussed neurochemical (and, ultimately, neurodevelopmental) effects of experimentally-induced maternal hypothyroidism, in a brain region-specific manner. Copyright © 2014 ISDN. Published by Elsevier Ltd. All rights reserved.

Inflammation-induced preterm lung maturation: lessons from animal experimentation.

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Moss, Timothy J M; Westover, Alana J

2017-06-01

Intrauterine inflammation, or chorioamnionitis, is a major contributor to preterm birth. Prematurity per se is associated with considerable morbidity and mortality resulting from lung immaturity but exposure to chorioamnionitis reduces the risk of neonatal respiratory distress syndrome (RDS) in preterm infants. Animal experiments have identified that an increase in pulmonary surfactant production by the preterm lungs likely underlies this decreased risk of RDS in infants exposed to chorioamnionitis. Further animal experimentation has shown that infectious or inflammatory agents in amniotic fluid exert their effects on lung development by direct effects within the developing respiratory tract, and probably not by systemic pathways. Differences in the effects of intrauterine inflammation and glucocorticoids demonstrate that canonical glucocorticoid-mediated lung maturation is not responsible for inflammation-induced changes in lung development. Animal experimentation is identifying alternative lung maturational pathways, and transgenic animals and cell culture techniques will allow identification of novel mechanisms of lung maturation that may lead to new treatments for the prevention of RDS. Copyright © 2016. Published by Elsevier Ltd.

Ionizing radiation-induced cancers. Experimental and clinical data

International Nuclear Information System (INIS)

Joveniaux, Alain.

1978-03-01

This work attempts to give an idea of radiocarcinogenesis, both experimental and clinical. Experimentally the possibility of radio-induced cancer formation has considerable doctrinal importance since it proves without question the carcinogenetic effect of radiations, and also yields basis information on the essential constants implicated in its occurrence: need for a latency time varying with the animal species and technique used, but quite long in relation to the specific lifetime of each species; importance of a massive irradiation, more conducive to cancerisation as long as it produces no necroses liable to stop the formation of any subsequent neoplasia; finally, rarity of is occurrence. Clinically although the cause and effect relationship between treatment and cancer is sometimes difficult to establish categorically, the fact is that hundreds of particularly disturbing observations remain and from their number often emerges under well-defined circumstances, an undeniable clinical certainty. Most importantly these observation fix the criteria necessary for the possibility of a radioinduced cancer to arise, i.e: the notion of a prior irradiation; the appearance of a cancer in the irradiation area; serious tissue damage in relation with an excessive radiation dose; a long latency period between irradition and appearance of the cancer [fr

Ethylenediaminetetraacetic acid induces antioxidant and anti-inflammatory activities in experimental liver fibrosis.

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González-Cuevas, J; Navarro-Partida, J; Marquez-Aguirre, A L; Bueno-Topete, M R; Beas-Zarate, C; Armendáriz-Borunda, J

2011-01-01

Experimental liver fibrosis induced by carbon tetrachloride (CCl(4)) is associated with oxidative stress, lipid peroxidation, and inflammation. This work was focused on elucidating the anti-inflammatory and antioxidant effects of ethylenediaminetetraacetic acid (EDTA) in this model of hepatotoxicity. Wistar male rats were treated with CCl(4) and EDTA (60, 120, or 240 mg/kg). Morphometric analyses were carried out in Masson's stained liver sections to determine fibrosis index. Coagulation tests prothrombin time (PT) and partial thromboplastin time (PTT) were also determined. Gene expression for transforming growth factor beta (TGF-beta1), alpha1(I) procollagen gene (alpha1 Col I), tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and superoxide dismutase (SOD) was monitored by real-time PCR. Antioxidant effect of EDTA was measured by its effects on lipid peroxidation; biological activity of ceruloplasmin (Cp), SOD, and catalase (Cat) were analyzed by zymography assays. Animals with CCl(4)-hepatic injury that received EDTA showed a decrement in fibrosis (20%) and lipid peroxidation (22%). The mRNA expression for TNF-alpha (55%), TGF-beta1 (50%), IL-6 (52%), and alpha1 Col I (60%) was also decreased. This group of animals showed increased Cp (62%) and SOD (25%) biological activities. Coagulation blood tests, Cat activity, and gene expression for SOD were not modified by EDTA treatment. This study demonstrates that EDTA treatment induces the activity of antioxidant enzymes, decreases lipid peroxidation, hepatic inflammation, and fibrosis in experimental liver fibrosis induced by CCl(4).

Influence of intramuscular granisetron on experimentally induced muscle pain by acidic saline.

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Louca, S; Ernberg, M; Christidis, N

2013-06-01

The aim of this study was to investigate whether intramuscular administration of the 5-HT(3) receptor antagonist granisetron reduces experimental muscle pain induced by repeated intramuscular injections of acidic saline into the masseter muscles. Twenty-eight healthy and pain-free volunteers, fourteen women and fourteen men participated in this randomized, double-blind and placebo-controlled study. After a screening examination and registration of the baseline pressure-pain threshold (PPT), the first simultaneous bilateral injections of 0·5 mL acidic saline (9 mg mL(-1) , pH 3·3) into the masseter muscles were performed. Two days later, PPT and pain (VAS) were re-assessed. The masseter muscle was then pre-treated with 0·5 mL granisetron (Kytril(®) 1 mg mL(-1) pH 5·3) on one side and control substance (isotonic saline, 9 mg mL(-1) pH 6) on the contralateral side. Two minutes thereafter a bilateral simultaneous injection of 0·5 mL acidic saline followed. The evoked pain intensity, pain duration, pain area and PPT were assessed. The volunteers returned 1 week later to re-assess VAS and PPT. On the side pre-treated with granisetron, the induced pain had significantly lower intensity and shorter duration (P granisetron on pain duration was significant only in women (P granisetron has a pain-reducing effect on experimentally induced muscle pain by repeated acidic saline injection. © 2013 John Wiley & Sons Ltd.

Fibroblast Growth Factor 21 Deficiency Attenuates Experimental Colitis-Induced Adipose Tissue Lipolysis

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Liming Liu

2017-01-01

Full Text Available Aims. Nutrient deficiencies are common in patients with inflammatory bowel disease (IBD. Adipose tissue plays a critical role in regulating energy balance. Fibroblast growth factor 21 (FGF21 is an important endocrine metabolic regulator with emerging beneficial roles in lipid homeostasis. We investigated the impact of FGF21 in experimental colitis-induced epididymal white adipose tissue (eWAT lipolysis. Methods. Mice were given 2.5% dextran sulfate sodium (DSS ad libitum for 7 days to induce colitis. The role of FGF21 was investigated using antibody neutralization or knockout (KO mice. Lipolysis index and adipose lipolytic enzymes were determined. In addition, 3T3-L1 cells were pretreated with IL-6, followed by recombinant human FGF21 (rhFGF21 treatment; lipolysis was assessed. Results. DSS markedly decreased eWAT/body weight ratio and increased serum concentrations of free fatty acid (FFA and glycerol, indicating increased adipose tissue lipolysis. eWAT intracellular lipolytic enzyme expression/activation was significantly increased. These alterations were significantly attenuated in FGF21 KO mice and by circulating FGF21 neutralization. Moreover, DSS treatment markedly increased serum IL-6 and FGF21 levels. IL-6 pretreatment was necessary for the stimulatory effect of FGF21 on adipose lipolysis in 3T3-L1 cells. Conclusions. Our results demonstrate that experimental colitis induces eWAT lipolysis via an IL-6/FGF21-mediated signaling pathway.

Numerical and experimental evaluation of residual strains induced by pulsed laser welding

International Nuclear Information System (INIS)

Touvrey, C.; Bruyere, V.; Namy, P.

2014-01-01

The aim of the present study is to compare the residual strains induced by different welding processes during the assembly of two Ti6Al4V thin sheets. Several welding configurations and two means (pulsed laser and continuous one) are tested. The first part of the study intends to experimentally quantify strains induced by laser-matter interaction when one of the plates can freely bend. In this configuration the residual stresses are minimum, and consequently the strains measurement constitute a good indicator of the mechanical evolution. The displacements are in-situ reported thanks to a mechanical sensor. The second part of the study is dedicated to the numerical modeling of the processes. Unfortunately, the model is not completely predictive and appears to be oversimplified to describe the measured distortion. As it appears difficult to model the laser-matter interaction (especially in the case of many impacts recovering), we have adopted an equivalent approach to simulate the thermal evolution within the work pieces. An optimization procedure has been developed to determine an equivalent thermal flux, which leads to a melted zone shape in good agreement with experimental evaluations. The thermo-mechanical problem is computed by means of the finite elements software COMSOL Multiphysics. The results are compared to experimental data (displacement measurements) throughout the complete simulation. We plan to apply the complete model for more complex geometries, involving the generation of residual stresses. (authors)

Status of experimental data of proton-induced reactions for intermediate-energy nuclear data evaluation

Energy Technology Data Exchange (ETDEWEB)

Watanabe, Yukinobu; Kawano, Toshihiko [Kyushu Univ., Fukuoka (Japan); Yamano, Naoki; Fukahori, Tokio

1998-11-01

The present status of experimental data of proton-induced reactions is reviewed, with particular attention to total reaction cross section, elastic and inelastic scattering cross section, double-differential particle production cross section, isotope production cross section, and activation cross section. (author)

Obesogenic diet-induced gut barrier dysfunction and pathobiont expansion aggravate experimental colitis.

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June-Chul Lee

Full Text Available Consumption of a typical Western diet is a risk factor for several disorders. Metabolic syndrome is the most common disease associated with intake of excess fat. However, the incidence of inflammatory bowel disease is also greater in subjects consuming a Western diet, although the mechanism of this phenomenon is not clearly understood. We examined the morphological and functional changes of the intestine, the first site contacting dietary fat, in mice fed a high-fat diet (HFD inducing obesity. Paneth cell area and production of antimicrobial peptides by Paneth cells were decreased in HFD-fed mice. Goblet cell number and secretion of mucin by goblet cells were also decreased, while intestinal permeability was increased in HFD-fed mice. HFD-fed mice were more susceptible to experimental colitis, and exhibited severe colonic inflammation, accompanied by the expansion of selected pathobionts such as Atopobium sp. and Proteobacteria. Fecal microbiota transplantation transferred the susceptibility to DSS-colitis, and antibiotic treatment abrogated colitis progression. These data suggest that an experimental HFD-induced Paneth cell dysfunction and subsequent intestinal dysbiosis characterized by pathobiont expansion can be predisposing factors to the development of inflammatory bowel disease.

Experimental studies of keV energy neutron-induced reactions relevant to astrophysics and nuclear physics

Energy Technology Data Exchange (ETDEWEB)

Shima, T.; Kii, T.; Kikuchi, T.; Okazaki, F.; Kobayashi, T.; Baba, T.; Nagai, Y. [Tokyo Inst. of Tech. (Japan). Faculty of Science; Igashira, M.

1997-03-01

Nuclear reactions induced by keV energy neutrons provide a plenty of informations for studies of both astrophysics and nuclear physics. In this paper we will show our experimental studies of neutron- induced reactions of light nuclei in the keV energy region by means of a pulsed keV neutron beam and high-sensitivity detectors. Also we will discuss astrophysical and nuclear-physical consequences by using the obtained results. (author)

Recombinant human acetylcholine receptor alpha-subunit induces chronic experimental autoimmune myasthenia gravis.

Science.gov (United States)

Lennon, V A; Lambert, E H; Leiby, K R; Okarma, T B; Talib, S

1991-04-01

A synthetic gene encoding the 210 N-terminal residues of the alpha-subunit of the nicotinic acetylcholine receptor (AChR) of human skeletal muscle was cloned into an inducible expression plasmid to produce a fusion protein in high yield in Escherichia coli. Like native human AChR, the recombinant human alpha 1-210 protein induced AChR-binding, AChR-modulating, and AChR-blocking autoantibodies in rats when injected once intradermally as an emulsion in CFA, with Bordetella pertussis vaccine as supplementary adjuvant. The minimum dose of recombinant protein required to induce biochemical signs of experimental autoimmune myasthenia gravis (EAMG) with 100% incidence was 2.2 micrograms. With 6.6 to 22 micrograms, serum levels of autoantibodies were persistent, and clinically apparent EAMG lasted more than a month. Clinical, electrophysiological, and biochemical indices of EAMG induced by doses of 66 micrograms or more were more uniformly severe and persistent, with 33% fatality. Rats receiving a control extract of E. coli containing plasmid without the alpha 1-210 codon insert, with adjuvants, did not develop autoantibodies or signs of EAMG. This highly reproducible new model of EAMG induced by a recombinant human autoantigen should be valuable for testing Ag-specific immunotherapeutic strategies that might be applicable to treating acquired myasthenia gravis in humans.

Experimental investigation of flow induced dust acoustic shock waves in a complex plasma

Energy Technology Data Exchange (ETDEWEB)

Jaiswal, S., E-mail: surabhijaiswal73@gmail.com; Bandyopadhyay, P.; Sen, A. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

2016-08-15

We report on experimental observations of flow induced large amplitude dust-acoustic shock waves in a complex plasma. The experiments have been carried out in a Π shaped direct current glow discharge experimental device using kaolin particles as the dust component in a background of Argon plasma. A strong supersonic flow of the dust fluid is induced by adjusting the pumping speed and neutral gas flow into the device. An isolated copper wire mounted on the cathode acts as a potential barrier to the flow of dust particles. A sudden change in the gas flow rate is used to trigger the onset of high velocity dust acoustic shocks whose dynamics are captured by fast video pictures of the evolving structures. The physical characteristics of these shocks are delineated through a parametric scan of their dynamical properties over a range of flow speeds and potential hill heights. The observed evolution of the shock waves and their propagation characteristics are found to compare well with model numerical results based on a modified Korteweg-de-Vries-Burgers type equation.

Spectroscopic evaluation of painted layer structural changes induced by gamma radiation in experimental models

International Nuclear Information System (INIS)

Manea, Mihaela M.; Moise, Ioan V.; Virgolici, Marian; Negut, Constantin D.; Barbu, Olimpia-Hinamatsuri; Cutrubinis, Mihalis; Fugaru, Viorel; Stanculescu, Ioana R.; Ponta, Corneliu C.

2012-01-01

The degradation of cultural heritage objects by insects and microorganisms is an important issue for conservators, art specialists and humankind in general. Gamma irradiation is an efficient method of polychrome wooden artifacts disinfestation. Color changes and other modifications in the physical chemical properties of materials induced by gamma irradiation are feared by cultural heritage responsible committees and they have to be evaluated objectively and precisely. In this paper FTIR and FT-Raman spectroscopy methods were used to investigate the structural changes in some experimental models of tempera paint layers on wood following 11 kGy gamma irradiation at two dose rates. Radiation chemistry depends on the particular pigment, matrix formed by protein, resin (in case of varnished samples) and water presence. For the majority of painted layer in experimental models very small spectral variations were observed. Small changes in the FTIR spectra were observed for the raw sienna experimental model: for the higher dose rate the egg yolk protein oxidation peaks and the CH stretching bands due to lipids degradation products increased. - Highlights: ► Experimental models of tempera paint layers on wood were γ-irradiated at two dose rates. ► Changes induced by γ-irradiation were evaluated by vibrational spectroscopy. ► Minor spectral variations of painted layer were observed. ► Raw sienna FTIR spectra showed little changes of egg yolk and lipids at higher dose rate. ► Gamma irradiation is recommended for disinfection of painted wooden artifacts.

Tramadol Induced Adrenal Insufficiency: Histological, Immunohistochemical, Ultrastructural, and Biochemical Genetic Experimental Study.

Science.gov (United States)

Abdelaleem, Shereen Abdelhakim; Hassan, Osama A; Ahmed, Rasha F; Zenhom, Nagwa M; Rifaai, Rehab A; El-Tahawy, Nashwa F

2017-01-01

Tramadol is a synthetic, centrally acting analgesic. It is the most consumed narcotic drug that is prescribed in the world. Tramadol abuse has dramatically increased in Egypt. Long term use of tramadol can induce endocrinopathy. So, the aim of this study was to analyze the adrenal insufficiency induced by long term use of tramadol in experimental animals and also to assess its withdrawal effects through histopathological and biochemical genetic study. Forty male albino rats were used in this study. The rats were divided into 4 groups (control group, tramadol-treated group, and withdrawal groups). Tramadol was given to albino rats at a dose of 80 mg/kg body weight for 3 months and after withdrawal periods (7-15 days) rats were sacrificed. Long term use of tramadol induced severe histopathological changes in adrenal glands. Tramadol decreased the levels of serum cortisol and DHEAS hormones. In addition, it increased the level of adrenal MDA and decreased the genetic expression of glutathione peroxidase and thioredoxin reductase in adrenal gland tissues. All these changes started to return to normal after withdrawal of tramadol. Thus, it was confirmed that long term use of tramadol can induce severe adrenal insufficiency.

Experimental studies on lung carcinogenesis and their relationship to future research on radiation-induced lung cancer in humans

International Nuclear Information System (INIS)

Cross, F.T.

1991-03-01

The usefulness of experimental systems for studying human lung carcinogenesis lies in the ease of studying components of a total problem. As an example, the main thrust of attack on possible synergistic interactions between radiation, cigarette smoke, and other irritants must be by means of research on animals. Because animals can be serially sacrificed, a systematic search can be made for progressive lung changes, thereby improving our understanding of carcinogenesis. The mechanisms of radiation-induced carcinogenesis have not yet been delineated, but modern concepts of molecular and cellular biology and of radiation dosimetry are being increasingly applied to both in vivo and in vitro exposure to determine the mechanisms of radiation-induced carcinogenesis, to elucidate human data, and to aid in extrapolating experimental animal data to human exposures. In addition, biologically based mathematical models of carcinogenesis are being developed to describe the nature of the events leading to malignancy; they are also an essential part of a rational approach to quantitative cancer risk assessment. This paper summarizes recent experimental and modeling data on radon-induced lung cancer and includes the confounding effects of cigarette-smoke exposures. The applicability of these data to understanding human exposures is emphasized, and areas of future research on human radiation-induced carcinogenesis are discussed. 7 refs., 2 figs., 3 tabs

Experimental realization of an on-chip all-optical analogue to electromagnetically induced transparency.

Science.gov (United States)

Xu, Qianfan; Sandhu, Sunil; Povinelli, Michelle L; Shakya, Jagat; Fan, Shanhui; Lipson, Michal

2006-03-31

We provide the first experimental observation of structure tuning of the electromagnetically induced transparency-like spectrum in integrated on-chip optical resonator systems. The system consists of coupled silicon ring resonators with 10 microm diameter on silicon, where the coherent interference between the two coupled resonators is tuned. We measured a transparency-resonance mode with a quality factor of 11,800.

Effects of fisetin on hyperhomocysteinemia-induced experimental endothelial dysfunction and vascular dementia.

Science.gov (United States)

Hemanth Kumar, Boyina; Arun Reddy, Ravula; Mahesh Kumar, Jerald; Dinesh Kumar, B; Diwan, Prakash V

2017-01-01

This study was designed to investigate the effects of fisetin (FST) on hyperhomocysteinemia (HHcy)-induced experimental endothelial dysfunction (ED) and vascular dementia (VaD) in rats. Wistar rats were randomly divided into 8 groups: control, vehicle control, l-methionine, FST (5, 10, and 25 mg/kg, p.o.), FST-per se (25 mg/kg, p.o.), and donepezil (0.1 mg/kg, p.o.). l-Methionine administration (1.7 g/kg, p.o.) for 32 days induced HHcy. ED and VaD induced by HHcy were determined by vascular reactivity measurements, behavioral analysis using Morris water maze and Y-maze, along with a biochemical and histological evaluation of thoracic aorta and brain tissues. Administration of l-methionine developed behavioral deficits; triggered brain lipid peroxidation (LPO); compromised brain acetylcholinesterase activity (AChE); and reduced the levels of brain superoxide dismutase (SOD), brain catalase (CAT), brain reduced glutathione (GSH), and serum nitrite; and increased serum homocysteine and cholesterol levels. These effects were accompanied by decreased vascular NO bioavailability, marked intimal thickening of the aorta, and multiple necrotic foci in brain cortex. HHcy-induced alterations in the activities of SOD, CAT, GSH, AChE, LPO, behavioral deficits, ED, and histological aberrations were significantly attenuated by treatment with fisetin in a dose-dependent manner. Collectively, our results indicate that fisetin exerts endothelial and neuroprotective effects against HHcy-induced ED and VaD.

Electron microscopic study of spontaneous and experimentally induced leukemia in IRC mice

International Nuclear Information System (INIS)

Hiraki, S.; Ranadive, K.J.; Dmochowski, L.

1974-01-01

Spontaneous, serially transplanted, and experimentally induced leukemias of ICRC mice were studied by electron microscopy in an attempt to detect the presence of virus particles, if any, and to observe the influence of chemical and hormonal treatment on the presence of these virus particles. The first series of experiments included spontaneous, serially transplanted, and radiation-induced leukemia. The paucity of type C virus particles was quite conspicuous in spontaneous leukemia. Serially transplanted and radiation-accelerated leukemic lesions showed the presence of some type C and intracisternal type A particles. Found in two of these leukemic lesions (thymus and lymphosarcoma), in addition to type C virus particles, were budding and some mature type B virus particles, and numerous intracytoplasmic type A particles. ''Viropexis'' of type B virus particles has been observed in the lymphosarcoma and in a leukemic thymus gland. The second series of experiments included leukemia induced in ovariectomized ICRC mice with 20-methylcholanthrene (MCA), pituitary transplants, and ovarian hormones (estradiol and estradiol-progesterone). In ovariectomized ICRC mice, leukemic lesions induced by MCA or pituitary transplants, or by MCA and pituitary transplants, showed type C virus particles and, in most cases, intracisternal type A particles. In leukemia induced in ovariectomized ICRC mice by MCA and estradiol, numerous intracytoplasmic type A particles were observed but no type C virus particles

Pattern differences in experimental fevers induced by endotoxin, endogenous pyrogen, and prostaglandins.

Science.gov (United States)

Morimoto, A; Nakamori, T; Watanabe, T; Ono, T; Murakami, N

1988-04-01

To distinguish pattern differences in experimentally induced fevers, we investigated febrile responses induced by intravenous (IV), intracerebroventricular (ICV), and intra-preoptic/anterior hypothalamic (POA) administration of bacterial endotoxin (lipopolysaccharide, LPS), endogenous pyrogen (EP), human recombinant interleukin-1 alpha (IL-1), and prostaglandins E2 and F2 alpha (PGE2 and PGF2 alpha). Intravenous LPS, EP, or IL-1 in high concentrations caused biphasic fever. In low concentrations, they induced only the first phase of fever. Latency to onset and time to first peak of fever induced by IV injection of LPS or EP were almost the same as those after ICV or POA injection of PGE2. Fever induced by ICV or POA administration of LPS, EP, IL-1, or PGF2 alpha had a long latency to onset and a prolonged time course. There were significant differences among the latencies to fever onset exhibited by groups that received ICV or POA injections of LPS, EP, or PGF2 alpha and by groups given IV injections of LPS or EP and ICV or POA injections of PGE2. Present observations indicate different patterns of fever produced by several kinds of pyrogens when given by various routes. These results permit us to consider the possibility that there are several mediators or multiprocesses underlying the pathogenesis of fever.

Possible antidepressant effects of vanillin against experimentally induced chronic mild stress in rats

Directory of Open Access Journals (Sweden)

Amira M. Abo-youssef

2016-06-01

Full Text Available Vanillin is a flavoring agent widely used in food and beverages such as chocolates and dairy products and it is also used to mask unpleasant tastes in medicine. It has been reported to have antioxidant, anti-inflammatory and antiapoptotic properties. The current study was designed to investigate the protective effects of vanillin against experimentally induced stress in rats. Briefly rats were subdivided into four groups. Three groups were subjected to chronic mild stress and the fourth group served as normal control group. One week before induction of stress drugs or saline was administered daily and continued for another nine weeks. At the end of the experimental period behavioral tests including sucrose preference test, forced swim test and elevated plus maze test were assessed. In addition, brain biochemical parameters including MDA, GSH, NO and serotonin were determined. Vanillin succeeded to restore the behavioral and biochemical changes associated with stress. It significantly increased sucrose consumption in sucrose preference test and time spent in open arm in elevated plus maze test as compared to stress control group. It also reduced immobility time in forced swim test and time spent in closed arm in elevated plus maze test. Additionally, it significantly decreased brain MDA and NO levels and significantly increased brain GSH and Serotonin levels compared to stress control group. It could be concluded that vanillin showed beneficial protective effects against experimentally induced stress in rats.

An experimental study on choroidal neovascularization induced by Krypton laser in rat model.

Science.gov (United States)

Cui, Jing; Liu, Yuanyuan; Zhang, Jingkai; Yan, Hua

2014-01-01

The purpose of this work was to study the efficacy and safety of choroidal neovascularization (CNV) formation induced by Krypton laser in Brown Norway (BN) rats, and observe the trend of the change of CNV after laser photocoagulation. Twenty-five male BN rats were involved in this study. Two eyes of one rat without any laser photocoagulation were randomly selected as the control group, and the other 48 eyes of 24 rats were selected as the experimental group. Eight eyes of four rats were randomly selected to receive the examinations of fundus fluorescein angiography (FFA), histopathology, and transmission electron microscopy 3, 7, 14, 21, 28, and 56 days after laser photocoagulation. After laser photocoagulation, the leakage appeared in burns on day 7 (59%), reached the peak on day 21 (84%), (p0.05). The thickness of CNV increased from day 7 to day 21 (p0.05). The experimental model of CNV can be successfully induced by Krypton laser in rats with a stable, long-lasting, and high success rate. After laser photocoagulation, the leakages appear on day 7, reach the peak on day 21, and remain stable after day 21.

Transcriptional profiling of the bovine hepatic response to experimentally induced E. coli mastitis

DEFF Research Database (Denmark)

Jørgensen, Hanne Birgitte Hede; Buitenhuis, Bart; Røntved, Christine Maria

2012-01-01

The mammalian liver works to keep the body in a state of homeostasis and plays an important role in systemic acute phase response to infections. In this study we investigated the bovine hepatic acute phase response at the gene transcription level in dairy cows with experimentally E. coli-induced ......The mammalian liver works to keep the body in a state of homeostasis and plays an important role in systemic acute phase response to infections. In this study we investigated the bovine hepatic acute phase response at the gene transcription level in dairy cows with experimentally E. coli......-induced mastitis. At time = 0, each of 16 periparturient dairy cows received 20-40 CFU of live E. coli in one front quarter of the udder. A time series of liver biopsies was collected at -144, 12, 24 and 192 hours relative to time of inoculation. Changes in transcription levels in response to E. coli inoculation...... were analyzed using the Bovine Genome Array and tested significant for 408 transcripts over the time series (adjusted p0.05; abs(fold-change)>2). After 2-D clustering, transcripts represented three distinct transcription profiles: 1) regulation of gene transcription and apoptosis, 2) responses...

[Effect of Capsicum annum L (pucunucho, ají mono) in gastric ulcer experimentally induced in rats].

Science.gov (United States)

Delgado Montero, Rocío; Flores Cortez, Daisy; Villalobos Pacheco, Eduardo

2015-01-01

To examine the effects of the Capsicum annum L lyophilized fruit extract in experimentally-induced gastric ulcer in rats. We used the model of indomethacin gastric ulcer-induced and the gastric ulcer model induced by pylorus ligation in rats. The rats were divided in five treatment groups as follow: G1: Distilled water 1 ml/Kg; G2: Ranitidine 50 mg/kg, G3: Capsicum 10mg/kg, G4: Capsicum 100 mg/kg, G5: Capsicum 1000 mg/kg. The results of the first model showed an ulcer inhibition of 60,4% and 66,7% using the doses of Capsicum at 10 mg/kg and 100 mg/kg, respectively. The results of the second model showed that neither the pH nor the volume of the gastric content were modified by the administered extract (p >0.05); however, by using the doses of Capsicum at 100 mg/kg and 1000 mg/kg, there was clearly an ulcer inhibition of 75.59% and 81.63% respectively, which were even greater than the inhibition obtained by ranitidine (75.51%). Therefore, in this experiment we demonstrated that the Capsicum annum L lyophilized fruit extract has a gastroprotective effect in experimentally-induced gastric ulcer in rats.

Long-term treadmill exercise-induced neuroplasticity and associated memory recovery of streptozotocin-induced diabetic rats: an experimenter blind, randomized controlled study.

Science.gov (United States)

You, Joshua Sung H; Kim, Chung-Ju; Kim, Mee Young; Byun, Yong Gwon; Ha, So Young; Han, Bong Suk; Yoon, Bum Chul

2009-01-01

We investigated a long-term exercise-induced neuroplasticity and spatial memory recovery in 15 rats in a treadmill as follows: normal control rats (NC), streptozotocin (STZ)-induced diabetic control rats (DC), and STZ-induced diabetic rats exercising in a treadmill (DE). As per the DE group, the running exercise in a treadmill was administered for 30 minutes a day for 6 weeks. Neuronal immediate-early gene (IEG) expression (c-Fos) in the hippocampus and radial arm maze (RAM) tests were measured and revealed that the c-Fos levels in DE were significantly higher than those in NC and DC (p memory performance scores, obtained from the RAM test, were significantly different among the three groups (p memory scores of NC and DE were higher than those of DC (p memory. This is the first experimental evidence in literature that supports the efficacy of exercise-induced neuroplasticity and spatial motor memory in diabetes care.

Experimental and theoretical studies on X-ray induced secondary electron yields in Ti and TiO2

International Nuclear Information System (INIS)

Iyasu, Takeshi; Tamura, Keiji; Shimizu, Ryuichi; Vlaicu, Mihai Aurel; Yoshikawa, Hideki

2006-01-01

Generation of X-ray induced secondary electrons in Ti and TiO 2 was studied from both experimental and theoretical approaches, using X-ray photoelectron spectroscopy (XPS) attached to a synchrotron radiation facility and Monte Carlo simulation, respectively. The experiment revealed that the yields of secondary electrons induced by X-rays (electrons/photon) at photon energies to 4950 and 5000eV for Ti and TiO 2 are δ Ti (4950eV)=0.002 and δ Ti (5000eV)=0.014 while those for TiO 2 are δ TiO 2 (4950eV)=0.003 and δ TiO 2 (5000eV)=0.018. A novel approach to obtain the escape depth of secondary electrons has been proposed and applied to Ti and TiO 2 . The approach agreed very well with the experimental data reported so far. The Monte Carlo simulation predicted; δ Ti * (4950eV)=0.002 and δ Ti * (5000eV)=0.011 while δ TiO 2 * (4950eV)=0.003 and δ TiO 2 * (5000eV)=0.015. An experimental examination on the contribution of X-ray induced secondary electrons to photocatalysis in TiO 2 has also been proposed

Tramadol Induced Adrenal Insufficiency: Histological, Immunohistochemical, Ultrastructural, and Biochemical Genetic Experimental Study

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Shereen Abdelhakim Abdelaleem

2017-01-01

Full Text Available Tramadol is a synthetic, centrally acting analgesic. It is the most consumed narcotic drug that is prescribed in the world. Tramadol abuse has dramatically increased in Egypt. Long term use of tramadol can induce endocrinopathy. So, the aim of this study was to analyze the adrenal insufficiency induced by long term use of tramadol in experimental animals and also to assess its withdrawal effects through histopathological and biochemical genetic study. Forty male albino rats were used in this study. The rats were divided into 4 groups (control group, tramadol-treated group, and withdrawal groups. Tramadol was given to albino rats at a dose of 80 mg/kg body weight for 3 months and after withdrawal periods (7–15 days rats were sacrificed. Long term use of tramadol induced severe histopathological changes in adrenal glands. Tramadol decreased the levels of serum cortisol and DHEAS hormones. In addition, it increased the level of adrenal MDA and decreased the genetic expression of glutathione peroxidase and thioredoxin reductase in adrenal gland tissues. All these changes started to return to normal after withdrawal of tramadol. Thus, it was confirmed that long term use of tramadol can induce severe adrenal insufficiency.

Experimental and theoretical study of steam condensation induced water hammer phenomena

International Nuclear Information System (INIS)

Barna, Imre Ferenc; Baranyai, Gabor; Ezsoel, Gyoergy

2009-01-01

We investigate steam condensation induced water hammer (waha) phenomena and present experimental and theoretical results. Some of the experiments were performed in the PMK-2 facility, which is a full-pressure thermohydraulic model of the nuclear power plant of VVER-440/312 type and located in the Atomic Energy Research Institute Budapest, Hungary. Other experiments were done in the ROSA facility in Japan. On the theoretical side waha is studied and analyzed with the WAHA3 model based on two-phase flow six first-order partial differential equations that present one dimensional, surface averaged mass, momentum and energy balances. A second order accurate high-resolution shock-capturing numerical scheme was applied with different kind of limiters in the numerical calculations. The applied two-fluid model shows some similarities to Relap5 which is widely used in the nuclear industry to simulate nuclear power plant accidents. Experimentally measured and theoretically calculated waha pressure peaks are in qualitative agreement. (author)

Effects of a Tumor Necrosis Factor-α Antagonist on Experimentally Induced Rhinosinusitis

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Dong-Hyun Kim

2011-01-01

Full Text Available This prospective, randomized, and controlled study examined the effects of tumor necrosis factor soluble receptor type I (sTNFRI, a TNF-α antagonist on experimentally induced rhinosinusitis in rats. The experimental groups received an instillation of lipopolysaccharide (LPS plus an intramuscular injection of amoxicillin/clavulanate (antibiotic group, an instillation of sTNFRI (sTNFRI group, an instillation of sTNFRI and an injection of amoxicillin/clavulanate (sTNFRI/antibiotic group, or no additional treatment (LPS group. Histopathological changes were determined using hematoxylin-eosin and periodic acid-Schiff (PAS staining. Leakage of exudate was determined using fluorescence microscopy. Vascular permeability was measured using the Evans blue dye technique. Expression of MUC5AC was measured using reverse transcriptase PCR. The sTNFRI, antibiotic, and sTNFRI/antibiotic groups had significantly less capillary permeability, mucosal edema, PAS staining, and expression of MUC5AC than the LPS group. There were no differences in capillary permeability, mucosal edema, PAS staining, and MUC5AC expression between the sTNFRI and sTNFRI/antibiotic groups. The antibiotic group had PAS staining similar to that of the sTNFRI and sTNFRI/antibiotic groups but had a greater increase in capillary permeability, mucosal edema, and MUC5AC expression. This study shows that sTNFRI reduces inflammatory activity and mucus hypersecretion in LPS-induced rhinosinusitis in rats.

Hepatoprotective and Antioxidant activity of Scoparia dulcis Linn, against N Nitrosodiethylamine (DEN) induced Hepatotoxicity in experimental Rats

OpenAIRE

Langeswaran K; Jagadeesan A. J; Vijayaprakash S; Balasubramanian M. P

2012-01-01

Scoparia dulcis Linn, belongs to the family Scrophulariaceae and have speculated Medicinal properties. In this present investigation, the antioxidant and hepatoprotective activity of the aqueous extracts of Scoparia dulcis was evaluated against N-nitrosodiethylamine (DEN) induced liver cirrhosis in experimental rats. In group III hepatotoxicity induced animals, an oral dose of 500 mg/kg, of the aqueous extracts of Scoparia dulcis exhibited a significant (P

Effects of Experimental Sarcocystis neurona-Induced Infection on Immunity in an Equine Model

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S. Rochelle Lewis

2014-01-01

Full Text Available Sarcocystis neurona is the most common cause of Equine Protozoal Myeloencephalitis (EPM, affecting 0.5–1% horses in the United States during their lifetimes. The objective of this study was to evaluate the equine immune responses in an experimentally induced Sarcocystis neurona infection model. Neurologic parameters were recorded prior to and throughout the 70-day study by blinded investigators. Recombinant SnSAG1 ELISA for serum and CSF were used to confirm and track disease progression. All experimentally infected horses displayed neurologic signs after infection. Neutrophils, monocytes, and lymphocytes from infected horses displayed significantly delayed apoptosis at some time points. Cell proliferation was significantly increased in S. neurona-infected horses when stimulated nonspecifically with PMA/I but significantly decreased when stimulated with S. neurona compared to controls. Collectively, our results suggest that horses experimentally infected with S. neurona manifest impaired antigen specific response to S. neurona, which could be a function of altered antigen presentation, lack of antigen recognition, or both.

Effects of Experimental Sarcocystis neurona-Induced Infection on Immunity in an Equine Model.

Science.gov (United States)

Lewis, S Rochelle; Ellison, Siobhan P; Dascanio, John J; Lindsay, David S; Gogal, Robert M; Werre, Stephen R; Surendran, Naveen; Breen, Meghan E; Heid, Bettina M; Andrews, Frank M; Buechner-Maxwell, Virginia A; Witonsky, Sharon G

2014-01-01

Sarcocystis neurona is the most common cause of Equine Protozoal Myeloencephalitis (EPM), affecting 0.5-1% horses in the United States during their lifetimes. The objective of this study was to evaluate the equine immune responses in an experimentally induced Sarcocystis neurona infection model. Neurologic parameters were recorded prior to and throughout the 70-day study by blinded investigators. Recombinant SnSAG1 ELISA for serum and CSF were used to confirm and track disease progression. All experimentally infected horses displayed neurologic signs after infection. Neutrophils, monocytes, and lymphocytes from infected horses displayed significantly delayed apoptosis at some time points. Cell proliferation was significantly increased in S. neurona-infected horses when stimulated nonspecifically with PMA/I but significantly decreased when stimulated with S. neurona compared to controls. Collectively, our results suggest that horses experimentally infected with S. neurona manifest impaired antigen specific response to S. neurona, which could be a function of altered antigen presentation, lack of antigen recognition, or both.

Elastase-induced pulmonary emphysema: insights from experimental models

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Mariana A. Antunes

2011-12-01

Full Text Available Several distinct stimuli can be used to reproduce histological and functional features of human emphysema, a leading cause of disability and death. Since cigarette smoke is the main cause of emphysema in humans, experimental researches have attempted to reproduce this situation. However, this is an expensive and cumbersome method of emphysema induction, and simpler, more efficacious alternatives have been sought. Among these approaches, elastolytic enzymes have been widely used to reproduce some characteristics of human cigarette smoke-induced disease, such as: augmentation of airspaces, inflammatory cell influx into the lungs, and systemic inflammation. Nevertheless, the use of elastase-induced emphysema models is still controversial, since the disease pathways involved in elastase induction may differ from those occurring in smoke-induced emphysema. This indicates that the choice of an emphysema model may impact the results of new therapies or drugs being tested. The aim of this review is to compare the mechanisms of disease induction in smoke and elastase emphysema models, to describe the differences among various elastase models, and to establish the advantages and disadvantages of elastase-induced emphysema models. More studies are required to shed light on the mechanisms of elastase-induced emphysema.Diversos estímulos podem ser utilizados para reproduzir características histológicas e funcionais do enfisema humano, uma das principais causas de incapacidade e morte. Uma vez que a fumaça de cigarro é a principal causa de enfisema em humanos, estudos experimentais têm tentado reproduzir esta situação. No entanto, esse é um método dispendioso e complicado para a indução do enfisema e, alternativas mais simples e eficazes, têm sido pesquisadas. Entre essas abordagens, enzimas elastolíticas vêm sendo amplamente utilizadas para reproduzir algumas das características do enfisema humano, tais como: aumento dos espaços a

Experimentally induced chocolate craving leads to an attentional bias in increased distraction but not in speeded detection.

Science.gov (United States)

Smeets, Elke; Roefs, Anne; Jansen, Anita

2009-12-01

In the present study, the causal influence of chocolate craving on attentional bias for chocolate-related information was examined by experimentally inducing chocolate craving in a sample of high trait chocolate cravers vs. low trait chocolate cravers. A sample of 35 high trait chocoholics and 33 low trait chocolate cravers were randomly assigned to either the exposure condition in which craving was manipulated or the non-exposure condition. To measure attentional bias, a pictorial version of the visual search paradigm [Smeets, E., Roefs, A., van Furth, E., & Jansen, A. (2008). Attentional bias for body and food in eating disorders: increased distraction, speeded detection, or both? Behaviour Research and Therapy, 46, 229-238] was used, assessing two components: distraction and detection. It was found that experimentally induced chocolate craving led to increased distraction by chocolate pictures in the high trait chocolate cravers, in comparison to the low trait chocolate cravers. Moreover, this measure of distraction correlated strongly with self-reported craving, but only in the chocoholics and in the exposure condition. In the non-exposure condition, high trait chocolate cravers showed speeded detection of chocolate pictures relative to non-chocoholics, but this component did not correlate with self-reported craving. It is concluded that experimentally induced craving for chocolate causes a bias in, specifically the increased distraction component of attention in high trait chocolate cravers.

Integrated system for production of neutronics and photonics calculational constants. Neutron-induced interactions: index of experimental data

International Nuclear Information System (INIS)

MacGregor, M.H.; Cullen, D.E.; Howerton, R.J.; Perkins, S.T.

1976-01-01

Indexes to the neutron-induced interaction data in the Experimental Cross Section Information Library (ECSIL) as of July 4, 1976 are tabulated. The tabulation has two arrangements: isotope (ZA) order and reaction-number order

Integrated system for production of neutronics and photonics calculational constants. Neutron-induced interactions: index of experimental data

Energy Technology Data Exchange (ETDEWEB)

MacGregor, M.H.; Cullen, D.E.; Howerton, R.J.; Perkins, S.T.

1976-07-04

Indexes to the neutron-induced interaction data in the Experimental Cross Section Information Library (ECSIL) as of July 4, 1976 are tabulated. The tabulation has two arrangements: isotope (ZA) order and reaction-number order.

Atorvastatin attenuates experimental contrast-induced acute kidney injury: a role for TLR4/MyD88 signaling pathway.

Science.gov (United States)

Yue, Rongzheng; Zuo, Chuan; Zeng, Jing; Su, Baihai; Tao, Ye; Huang, Songmin; Zeng, Rui

2017-11-01

To investigate the protective effect of different atorvastatin doses on contrast-induced acute kidney injury and the related mechanism. Healthy male Sprague-Dawley (SD) rats were randomly divided into the blank control group, experimental control group and different-dose atorvastatin groups. A rat model of contrast-induced acute kidney injury was established. We detected changes in serum creatinine (Scr) and blood urea nitrogen (BUN) before and after model establishment, observed and scored renal tubular injury, analyzed rat renal cell apoptosis, and measure the expression of signal pathway proteins and downstream inflammatory factors. After contrast agent injection, the Scr and BUN levels of the experimental control group were significantly increased, the different doses applied in the atorvastatin group significantly reduced the Scr and BUN levels (p atorvastatin doses have protective effects on contrast-induced acute renal tubular injury in rats, possibly by targeting TLR4, suppressing TLR4 expression, regulating the TLR4/Myd88 signaling pathway, and inhibiting the expression of downstream inflammatory factors.

The Effect of Experimental Parkinson on Formalin-Induced Pain in Rat

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Mohammad Sofiabadi

2014-04-01

Full Text Available Background & Objectives : Pain is one of the preceding claims of Parkinson's disease (PD, that its mechanisms have not been fully identified. The purpose of this study was to investigate the chemical pain responses induced by subcutaneous injection of formalin in male parkinsonized rats.   Method : In this experimental study, 40 Wistar male rats were used and PD was established by stereotaxic injection of 6-OHDA toxin into the striatum. Parkinson's disease severity determined by apomorphine-induced rotation test and then the pain response of 4 groups, the control, sham and 2 weak or full Parkinson groups, were evaluated using formalin test. Data were analyzed using ANOVA and Tukey test.   Results : In both acute and chronic phases of the formalin test, the symptoms of pain in different groups were same, but at the interphase stage, pain intensity increased more in Parkinson 's rats, especially in full PD group compared to control (p<0.01.   Conclusion: These results suggest that the nigrostriatal dopaminergic pathway have important modulating role on chronic pain.

The ultrastructural alterations in rat corneas with experimentally-induced diabetes mellitus

International Nuclear Information System (INIS)

Take, G.; Karabay, G.; Erdogan, D.; Duyar, I.

2006-01-01

To examine the ultrastructural changes of rat corneas in streptozotocin (STZ) induced diabetes mellitus and the and the follow-up insulin treatment. Sprague-Dawley type rats were used for experimental procedures during the period from January to April 2003 at Baskent University, Ankara, Turkey. Rats were studied in four groups: group 1: controls, group 2 sham controls (single dose IV sodium citrate); group 3 STZ-induced diabetes mellitus (Single dose 45mg/kg STZ intravenously), group 4: diabetes mellitus + insulin treatment (8U/day). We observed degenerative changes in the epithelial layer, stromal keratocytes and endothelial cells in diabetic group. In contrast, the corneal layers have revealed positive alterations in the insulin-treated group. The statistical analysis, showed significant narrowing in the epithelial layer in the diabetic group (p0.02), whereas thickening was observed in the epithelial basement membrane and Descemet's membrane (p=0.002). It was determined that that diabetes mellitus causes degenerative changes in cornea, which are positively influenced by short-term insulin treatment. (author)

Morphological and functional determinants of fluoxetine (Prozac)-induced pulmonary disease in an experimental model.

Science.gov (United States)

Capelozzi, Marco A; Leick-Maldonado, Edna A; Parra, Edwin R; Martins, Mílton A; Tibério, Iolanda F L C; Capelozzi, Vera L

2007-05-14

Fluoxetine treatment effects were determined by evaluating respiratory mechanics (elastance/resistance) and exhaled nitric oxide, as well as mononuclear and polymorphonuclear cell recruitment into the lungs, in an experimental guinea pig model. Guinea pigs were divided into four groups: Fl (fluoxetine only, n=7); Fl+Sw (fluoxetine and forced swimming, n=7); Ns+Sw (normal saline and forced swimming, n=8); and Ns (normal saline only, n=8). Treated animals received oral fluoxetine (10 mg/(kg day)) for 30 consecutive days. On day 31, all animals were anesthetized and mechanically ventilated so that respiratory system elastance and resistance, as well exhaled nitric oxide, could be determined. The lungs were then excised en bloc for histological and immunohistochemical evaluation. Forced swimming induced bronchodilation in untreated animals and bronchoconstriction in fluoxetine-treated animals. Fluoxetine treatment was also associated with mononuclear infiltration (predominantly into alveolar walls) and neutrophil recruitment. In addition, levels of exhaled nitric oxide, an inflammatory marker, were higher in fluoxetine-treated animals. Swimming-induced stress also amplified mononuclear cell recruitment to the lungs. These results show that, in this experimental model, fluoxetine treatment reproduces the pathology of chronic interstitial pneumonia in humans.

Experimental chaotic quantification in bistable vortex induced vibration systems

Science.gov (United States)

Huynh, B. H.; Tjahjowidodo, T.

2017-02-01

The study of energy harvesting by means of vortex induced vibration systems has been initiated a few years ago and it is considered to be potential as a low water current energy source. The energy harvester is realized by exposing an elastically supported blunt structure under water flow. However, it is realized that the system will only perform at a limited operating range (water flow) that is attributed to the resonance phenomenon that occurs only at a frequency that corresponds to the fluid flow. An introduction of nonlinear elements seems to be a prominent solution to overcome the problem. Among many nonlinear elements, a bistable spring is known to be able to improve the harvested power by a vortex induced vibrations (VIV) based energy converter at the low velocity water flows. However, it is also observed that chaotic vibrations will occur at different operating ranges that will erratically diminish the harvested power and cause a difficulty in controlling the system that is due to the unpredictability in motions of the VIV structure. In order to design a bistable VIV energy converter with improved harvested power and minimum negative effect of chaotic vibrations, the bifurcation map of the system for varying governing parameters is highly on demand. In this study, chaotic vibrations of a VIV energy converter enhanced by a bistable stiffness element are quantified in a wide range of the governing parameters, i.e. damping and bistable gap. Chaotic vibrations of the bistable VIV energy converter are simulated by utilization of a wake oscillator model and quantified based on the calculation of the Lyapunov exponent. Ultimately, a series of experiments of the system in a water tunnel, facilitated by a computer-based force-feedback testing platform, is carried out to validate the existence of chaotic responses. The main challenge in dealing with experimental data is in distinguishing chaotic response from noise-contaminated periodic responses as noise will smear

Experimental investigation of cavitation induced air release

Science.gov (United States)

Kowalski, Karoline; Pollak, Stefan; Hussong, Jeanette

Variations in cross-sectional areas may lead to pressure drops below a critical value, such that cavitation and air release are provoked in hydraulic systems. Due to a relatively slow dissolution of gas bubbles, the performance of hydraulic systems will be affected on long time scales by the gas phase. Therefore predictions of air production rates are desirable to describe the system characteristics. Existing investigations on generic geometries such as micro-orifice flows show an outgassing process due to hydrodynamic cavitation which takes place on time scales far shorter than diffusion processes. The aim of the present investigation is to find a correlation between global, hydrodynamic flow characteristics and cavitation induced undissolved gas fractions generated behind generic flow constrictions such as an orifice or venturi tube. Experimental investigations are realised in a cavitation channel that enables an independent adjustment of the pressure level upstream and downstream of the orifice. Released air fractions are determined by means of shadowgraphy imaging. First results indicate that an increased cavitation activity leads to a rapid increase in undissolved gas volume only in the choking regime. The frequency distribution of generated gas bubble size seems to depend only indirectly on the cavitation intensity driven by an increase of downstream coalescence events due to a more densely populated bubbly flow.

Changes in thermal nociceptive responses in dairy cows following experimentally induced Esherichia coli mastitis

DEFF Research Database (Denmark)

Rasmussen, Ditte B.; Fogsgaard, Katrine; Røntved, Christine Maria

2011-01-01

Mastitis is a high incidence disease in dairy cows. The acute stage is considered painful and inflammation can lead to hyperalgesia and thereby contribute to decreased welfare. The aim of this study was to examine changes in nociceptive responses toward cutaneous nociceptive laser stimulation (NLS......) in dairy cows with experimentally induced Escherichia coli mastitis, and correlate behavioral changes in nociceptive responses to clinical and paraclinical variables....

Experimentally induced spermatophore production and immune responses reveal a trade-off in crickets

OpenAIRE

Angela M. Kerr; Susan N. Gershman; Scott K. Sakaluk

2010-01-01

The energetic demands of the immune system and reproduction are often high and can lead to trade-offs between these 2 life-history traits. In decorated crickets, Gryllodes sigillatus, much of a male's reproductive effort is devoted to calling, and to the synthesis of a spermatophylax, a large, gelatinous, non--sperm-containing mass forming part of the spermatophore and consumed by the female after mating. We employed a reciprocal design in which we experimentally induced an immune response in...

Endovascular treatment of experimentally induced aneurysms in rabbits using stents: a feasibility study

International Nuclear Information System (INIS)

Hans, F.J.; Thiex, R.; Gilsbach, J.M.; Krings, T.; Moeller-Hartmann, W.; Dreeskamp, H.; Stein, K.P.; Meetz, A.; Thron, A.; Pfeffer, J.; Scherer, K.; Brunn, A.

2003-01-01

Although Guglielmi detachable coil (GDC) systems have been generally accepted for treatment of intracranial aneurysms, primary stenting of aneurysms using porous stents or implantation of coils after stent placement remains experimental. Testing of these new methods requires an animal model which imitates human aneurysms in size, configuration and neck morphology. We assessed in detail the technical requirements of and steps for transfemoral stent treatment of experimentally induced aneurysms at the top of the brachiocephalic trunk in rabbits. We created aneurysms in ten rabbits by distal ligation and intraluminal digestion of the right common carotid artery with elastase. We treated five animals with porous stents alone, and five with stents plus coiling via the meshes of the stent, which permitted dense packing of coils. No complications related to the procedures occurred. In all animals, even in those treated solely with porous stents, total occlusion of the aneurysm was achieved. Our animal model can be suitable for testing the biocompatibility and occlusion rate of new methods and devices for the treatment of experimental aneurysms. (orig.)

True Triaxial Experimental Study of Rockbursts Induced By Ramp and Cyclic Dynamic Disturbances

Science.gov (United States)

Su, Guoshao; Hu, Lihua; Feng, Xiating; Yan, Liubin; Zhang, Gangliang; Yan, Sizhou; Zhao, Bin; Yan, Zhaofu

2018-04-01

A modified rockburst testing system was utilized to reproduce rockbursts induced by ramp and cyclic dynamic disturbances with a low-intermediate strain rate of 2 × 10-3-5 × 10-3 s-1 in the laboratory. The experimental results show that both the ramp and cyclic dynamic disturbances play a significant role in inducing rockbursts. In the tests of rockbursts induced by a ramp dynamic disturbance, as the static stress before the dynamic disturbance increases, both the strength of specimens and the kinetic energy of the ejected fragments first increase and then decrease. In the tests of rockbursts induced by a cyclic dynamic disturbance, there exists a rockburst threshold of the static stress and the dynamic disturbance amplitude, and the kinetic energy of the ejected fragments first increases and then decreases as the cyclic dynamic disturbance frequency increases. The main differences between rockbursts induced by ramp dynamic disturbances and those induced by cyclic dynamic disturbances are as follows: the rockburst development process of the former is characterized by an impact failure feature, while that of the latter is characterized by a fatigue failure feature; the damage evolution curve of the specimen of the former has a leap-developing form with a significant catastrophic feature, while that of the latter has an inverted S-shape with a remarkable fatigue damage characteristic; the energy mechanism of the former involves the ramp dynamic disturbance giving extra elastic strain energy to rocks, while that of the latter involves the cyclic dynamic disturbance decreasing the ultimate energy storage capacity of rocks.

Combined experimental and numerical investigation of energy harness utilizing vortex induced vibration over half cylinder using piezoelectric beams

Science.gov (United States)

Ahmed, Md. Tusher; Hossain, Md. Tanver; Rahman, Md. Ashiqur

2017-06-01

Energy harvesting technology has the ability to create self-powered electronic systems that do not rely on battery power for their operation. Wind energy can be converted into electricity via a piezoelectric transducer during the air flow over a cylinder. The vortex-induced vibration over the cylinder causes the piezoelectric beam to vibrate. Thus useful electric energy at the range 0.2-0.3V is found which can be useful for self-powering small electronic devices. In the present study, prototypes of micro-energy harvester with a shape of 65 mm × 37 mm × 0.4 mm are developed and tested for airflow over D-shaped bluff body for diameters of 15, 20 and 28mm in an experimental setup consisting of a long wind tunnel of 57cm × 57cm with variable speeds of the motor for different flow velocities and the experimental setup is connected at the downstream where flow velocity is the maximum. Experimental results show that the velocity and induced voltage follows a regular linear pattern. A maximum electrical potential of 140 mV for velocity of 1.1 ms-1 at a bluff body diameter of 15 mm is observed in the energy harvester that can be applied in many practical cases for self-powering electronic devices. The simulation of this energy harvesting phenomena is then simulated using COMSOLE multi-physics. Diameter of the bluff bodies as well as flow velocity and size of cantilever beam are varied and the experimental findings are found to be in good agreement with the simulated ones. The simulations along with the experimental data show the possibility of generating electricity from vortex induced vibration and can be applied in many practical cases for self-powering electronic devices.

Morphological and behavioral markers of environmentally induced retardation of brain development: an animal model

International Nuclear Information System (INIS)

Altman, J.

1987-01-01

In most neurotoxicological studies morphological assessment focuses on pathological effects, like degenerative changes in neuronal perikarya, axonopathy, demyelination, and glial and endothelial cell reactions. Similarly, the assessment of physiological and behavioral effects center on evident neurological symptoms, like EEG and EMG abnormalities, resting and intention tremor, abnormal gait, and abnormal reflexes. This paper reviews briefly another central nervous system target of harmful environmental agents, which results in behavioral abnormalities without any qualitatively evident neuropathology. This is called microneuronal hypoplasia, a retardation of brain development characterized by a quantitative reduction in the normal population of late-generated, short-axoned neurons in specific brain regions. Correlated descriptive and experimental neurogenetic studies in the rat have established that all the cerebellar granule cells and a very high proportion of hippocampal granule cells are produced postnatally, and that focal, low-dose X-irradiation either of the cerebellum or of the hippocampus after birth selectively interferes with the acquisition of the full complement of granule cells (microneuronal hypoplasia). Subsequent behavioral investigations showed that cerebellar microneuronal hypoplasia results in profound hyperactivity without motor abnormalities, while hippocampal microneuronal hypoplasia results in hyperactivity, as well as attentional and learning deficits. There is much indirect clinical evidence that various harmful environmental agents affecting the pregnant mother and/or the infant lead to such childhood disorders as hyperactivity and attentional and learning disorders. 109 references

The effects of experimental pain and induced optimism on working memory task performance.

Science.gov (United States)

Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L

2016-07-01

Pain can interrupt and deteriorate executive task performance. We have previously shown that experimentally induced optimism can diminish the deteriorating effect of cold pressor pain on a subsequent working memory task (i.e., operation span task). In two successive experiments we sought further evidence for the protective role of optimism on pain-induced working memory impairments. We used another working memory task (i.e., 2-back task) that was performed either after or during pain induction. Study 1 employed a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain)×2 (pre-score vs. post-score) mixed factorial design. In half of the participants optimism was induced by the Best Possible Self (BPS) manipulation, which required them to write and visualize about a life in the future where everything turned out for the best. In the control condition, participants wrote and visualized a typical day in their life (TD). Next, participants completed either the cold pressor task (CPT) or a warm water control task (WWCT). Before (baseline) and after the CPT or WWCT participants working memory performance was measured with the 2-back task. The 2-back task measures the ability to monitor and update working memory representation by asking participants to indicate whether the current stimulus corresponds to the stimulus that was presented 2 stimuli ago. Study 2 had a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain) mixed factorial design. After receiving the BPS or control manipulation, participants completed the 2-back task twice: once with painful heat stimulation, and once without any stimulation (counter-balanced order). Continuous heat stimulation was used with temperatures oscillating around 1°C above and 1°C below the individual pain threshold. In study 1, the results did not show an effect of cold pressor pain on subsequent 2-back task performance. Results of study 2 indicated that heat pain impaired concurrent 2-back task performance. However, no evidence was found

The influence of experimentally induced pain on shoulder muscle activity

DEFF Research Database (Denmark)

Diederichsen, L.P.; Winther, A.; Dyhre-Poulsen, P.

2009-01-01

muscles. EMG was recorded before pain, during pain and after pain had subsided and pain intensity was continuously scored on a visual analog scale (VAS). During abduction, experimentally induced pain in the supraspinatus muscle caused a significant decrease in activity of the anterior deltoid, upper......-105A degrees) at a speed of approximately 120A degrees/s, controlled by a metronome. During abduction, electromyographic (EMG) activity was recorded by intramuscular wire electrodes inserted in two deeply located shoulder muscles and by surface-electrodes over six superficially located shoulder...... trapezius and the infraspinatus and an increase in activity of lower trapezius and latissimus dorsi muscles. Following subacromial injection a significantly increased muscle activity was seen in the lower trapezius, the serratus anterior and the latissimus dorsi muscles. In conclusion, this study shows...

Experimentally induced mastitis and metritis modulate soy bean derived isoflavone biotransformation in diary cows.

Science.gov (United States)

Kowalczyk-Zieba, I; Woclawek-Potocka, I; Piskula, M K; Piotrowska-Tomala, K K; Boruszewska, D; Bah, M M; Siemieniuch, M J; Skarzynski, D J

2011-12-01

The present study compared the changes in isoflavone (daidzein and genistein) and their metabolite (equol and para-ethyl-phenol) concentrations in the blood plasma of cows with induced mastitis and metritis after feeding with soy bean. Sixteen cows were divided into four groups: control for mastitis group, cows with induced mastitis group, control for metritis group, and cows with induced metritis group. All cows were fed a single dose of 2.5 kg of soy bean and then blood samples were taken from the jugular vein for 8 h at predetermined intervals. The concentrations of soy bean-derived isoflavones and their active metabolites were measured in the blood plasma on HPLC system. β-Glucuronidase activity in the blood plasma of cows was measured by fluorometric method. In the blood plasma of cows with induced mastitis and metritis, we found considerably higher concentrations and time-dependent increase in isoflavone metabolites (equol and para-ethyl-phenol) with reference to cyclic cows (P < 0.05). Moreover, we noticed significant decrease of genistein in the blood plasma of the cows with induced metritis compared with control cows (P < 0.05). In addition, in the blood plasma of the cows with induced metritis, we found an increase in β-glucuronidase activity compared with control cows (P < 0.05). In conclusion, health status of the females influenced the concentrations of isoflavone metabolites in the blood plasma of the cows. Experimentally induced mastitis and metritis increased isoflavone absorption, biotransformation and metabolism. Therefore, we suggest that cows with induced mastitis and metritis are more exposed to active isoflavone metabolite actions than healthy cows. Copyright © 2011. Published by Elsevier Inc.

The effect of preferred music genre selection versus preferred song selection on experimentally induced anxiety levels.

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Walworth, Darcy DeLoach

2003-01-01

The purpose of this study was to investigate the differences of experimentally induced anxiety levels reached by subjects listening to no music (n = 30), subjects listening to music selected by the experimenter from the subject's preferred genre or artist listed as relaxing (n = 30), and subjects listening to a specific song they listed as relaxing (n = 30). Subjects consisted of 90 individuals, male and female, randomly assigned to one of the three groups mentioned above. Subjects in either music group filled out a questionnaire prior to participating in the study indicating their preference of music used for relaxation purposes. Subjects in Experimental Group 1 marked their preferred genres and/or artists, and Experimental Group 2 marked specific songs used for relaxation purposes. While the experimenter hypothesized subjects in Experimental Group 2 would show less anxiety than both the control group and Experimental Group 1, there were no significant differences found between the 2 music groups in anxiety levels reached. However, there was a statistically significant difference between the no music control group and both music groups in the anxiety level reached by subjects. Subjects listening to music, both songs chosen by the experimenter and subject selected songs, showed significantly less anxiety than subjects not listening to music.

Experimental investigation of cavitation induced air release

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Kowalski Karoline

2017-01-01

Full Text Available Variations in cross-sectional areas may lead to pressure drops below a critical value, such that cavitation and air release are provoked in hydraulic systems. Due to a relatively slow dissolution of gas bubbles, the performance of hydraulic systems will be affected on long time scales by the gas phase. Therefore predictions of air production rates are desirable to describe the system characteristics. Existing investigations on generic geometries such as micro-orifice flows show an outgassing process due to hydrodynamic cavitation which takes place on time scales far shorter than diffusion processes. The aim of the present investigation is to find a correlation between global, hydrodynamic flow characteristics and cavitation induced undissolved gas fractions generated behind generic flow constrictions such as an orifice or venturi tube. Experimental investigations are realised in a cavitation channel that enables an independent adjustment of the pressure level upstream and downstream of the orifice. Released air fractions are determined by means of shadowgraphy imaging. First results indicate that an increased cavitation activity leads to a rapid increase in undissolved gas volume only in the choking regime. The frequency distribution of generated gas bubble size seems to depend only indirectly on the cavitation intensity driven by an increase of downstream coalescence events due to a more densely populated bubbly flow.

Lymphocytes contribute to biliary injury and fibrosis in experimental xenobiotic-induced cholestasis

International Nuclear Information System (INIS)

Joshi, Nikita; Kopec, Anna K.; Cline-Fedewa, Holly; Luyendyk, James P.

2017-01-01

The etiology of chronic bile duct injury and fibrosis in patients with autoimmune cholestatic liver diseases is complex, and likely involves immune cells such as lymphocytes. However, most models of biliary fibrosis are not autoimmune in nature. Biliary fibrosis can be induced experimentally by prolonged exposure of mice to the bile duct toxicant alpha-naphthylisothiocyanate (ANIT). We determined whether lymphocytes contributed to ANIT-mediated biliary hyperplasia and fibrosis in mice. Hepatic accumulation of T-lymphocytes and increased serum levels of anti-nuclear-autoantibodies were evident in wild-type mice exposed to ANIT (0.05% ANIT in chow). This occurred alongside bile duct hyperplasia and biliary fibrosis. To assess the role of lymphocytes in ANIT-induced biliary fibrosis, we utilized RAG1 −/− mice, which lack T- and B-lymphocytes. ANIT-induced bile duct injury, indicated by increased serum alkaline phosphatase activity, was reduced in ANIT-exposed RAG1 −/− mice compared to ANIT-exposed wild-type mice. Despite this reduction in biliary injury, ANIT-induced bile duct hyperplasia was similar in wild-type and RAG1 −/− mice. However, hepatic induction of profibrogenic genes including COL1A1, ITGβ6 and TGFβ2 was markedly attenuated in ANIT-exposed RAG1 −/− mice compared to ANIT-exposed wild-type mice. Peribiliary collagen deposition was also reduced in ANIT-exposed RAG1 −/− mice. The results indicate that lymphocytes exacerbate bile duct injury and fibrosis in ANIT-exposed mice without impacting bile duct hyperplasia.

Saturation of the laser-induced narrowband coherent synchrotron radiation process: Experimental observation at a storage ring

Science.gov (United States)

Hosaka, M.; Yamamoto, N.; Takashima, Y.; Szwaj, C.; Le Parquier, M.; Evain, C.; Bielawski, S.; Adachi, M.; Zen, H.; Tanikawa, T.; Kimura, S.; Katoh, M.; Shimada, M.; Takahashi, T.

2013-02-01

We study the efficiency limitation affecting laser-induced coherent synchrotron radiation (CSR) at high laser power. Experiments are made on the UVSOR-II storage ring in conditions of narrowband terahertz CSR emission. While, at moderate power, CSR power increases quadratically with laser power, a noticeable decrease in efficiency and eventually a decrease in CSR power is observed experimentally at high power. Details of the underlying process are analyzed numerically. As the saturation effect depends almost instantaneously on the laser intensity, the saturation occurs locally in longitudinal space. This has important consequences on the modulation pattern induced on the electron bunch.

The relevance of cytokines in the radiation-induced lung reaction. Experimental basis and clinical significance

International Nuclear Information System (INIS)

Ruebe, C.E.; Ruebe, C.; Rodemann, H.P.

2004-01-01

Methods: published data on radiation-induced cytokine expression from experimental and clinical studies are reviewed. Results and conclusion: the major pro-inflammatory cytokines in the radiation response of the lung include tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), and interleukin-6 (IL-6). Transforming growth factor-β (TGF-β) appears to be of particular importance in the development of lung fibrosis. First approaches with radioprotective agents and gene therapy to modify radiation-induced cytokine expression have been investigated for prevention of late effects of irradiation lung damage in animal experiments. Preliminary data of clinical studies suggest that elevated plasma TGF-β-levels during radiotherapy may predict the development of symptomatic radiation pneumonitis. The biological impacts of endogenous radiation-induced cytokine production by tumor cells in respect of tumor behavior, potential damage to normal tissue, and clinical status of the host still need to be determined more precisely. (orig.)

Human experimental anxiety: actual public speaking induces more intense physiological responses than simulated public speaking.

Science.gov (United States)

Zuardi, Antonio Waldo; Crippa, José Alexandre de Souza; Hallak, Jaime Eduardo Cecílio; Gorayeb, Ricardo

2013-01-01

a) To perform a systematic and meta-analytic review to verify whether the Simulated Public Speaking Task (SPST) leads to a greater increase in self-rated anxiety than in physiological correlates of anxiety; and b) to compare the results obtained with the SPST with an actual public speaking task involving healthy volunteers. a) The PubMed and ISI Web of Knowledge databases were searched for studies involving the SPST prior to 2012. Eleven publications were eligible and provided data from 143 healthy volunteers for meta-analysis; b) 48 university students without somatic or psychiatric disorders were divided into three experimental groups of 16 subjects to undergo one of the following: SPST, real-world public speaking task (real-world), and control situation (control). The meta-analysis showed that the SPST induced a significant increase in the Visual Analogue Mood Scale (VAMS) anxiety factor, but no significant increases in systolic blood pressure or heart rate. The empirical study showed that the real-world public speaking task increased heart rate, systolic blood pressure and diastolic blood pressure significantly more than the control and SPST conditions. These results suggest that real public speaking might be better than SPST in inducing experimental anxiety.

Foraminiferal survival after long-term in situ experimentally induced anoxia

Science.gov (United States)

Langlet, D.; Geslin, E.; Baal, C.; Metzger, E.; Lejzerowicz, F.; Riedel, B.; Zuschin, M.; Pawlowski, J.; Stachowitsch, M.; Jorissen, F. J.

2013-11-01

Anoxia was successfully induced in four benthic chambers installed at 24 m depth on the northern Adriatic seafloor from 9 days to 10 months. To accurately determine whether benthic foraminifera can survive experimentally induced prolonged anoxia, the CellTrackerTM Green method was applied and calcareous and agglutinated foraminifera were analyzed. Numerous individuals were found living at all sampling times and at all sampling depths (to 5 cm), supported by a ribosomal RNA analysis that revealed that certain benthic foraminifera were active after 10 months of anoxia. The results show that benthic foraminifera can survive up to 10 months of anoxia with co-occurring hydrogen sulfides. However, foraminiferal standing stocks decrease with sampling time in an irregular manner. A large difference in standing stock between two cores sampled under initial conditions indicates the presence of a large spatial heterogeneity of the foraminiferal faunas. An unexpected increase in standing stocks after one month is tentatively interpreted as a reaction to increased food availability due to the massive mortality of infaunal macrofaunal organisms. After this, standing stocks decrease again in cores sampled after 2 months of anoxia to then attain a minimum in the cores sampled after 10 months. We speculate that the trend of overall decrease of standing stocks is not due to the adverse effects of anoxia and hydrogen sulfides but rather due to a continuous diminution of labile organic matter.

Chemopreventive effect of Cynodon dactylon (L.) Pers. extract against DMH-induced colon carcinogenesis in experimental animals.

Science.gov (United States)

Albert-Baskar, Arul; Ignacimuthu, Savarimuthu

2010-07-01

The present study was aimed at evaluating the chemopreventive property of Cynodon dactylon. The antioxidant, antiproliferative and apoptotic potentials of the plant were investigated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, nitric oxide radical scavenging activity (NO(-)) and MTT assay on four cancer cell lines (COLO 320 DM, MCH-7, AGS, A549) and a normal cell line (VERO). In vivo chemopreventive property of the plant extract was studied in DMH-induced colon carcinogenesis. The methanolic extract of C. dactylon was found to be antiproliferative and antioxidative at lower concentrations and induced apoptotic cell death in COLO 320 DM cells. Treatment with methanolic extract of C. dactylon increased the levels of antioxidant enzymes and reduced the number of dysplastic crypts in DMH-induced colon of albino rats. The present investigation revealed the anticancer potential of methanolic extract of C. dactylon in COLO 320 DM cells and experimentally induced colon carcinogenesis in rats.

Effects of normal saline and selenium-enriched hot spring water on experimentally induced rhinosinusitis in rats.

Science.gov (United States)

Kim, Dong-Hyun; Yeo, Sang Won

2013-01-01

This prospective, randomized, and controlled study examined the effects of normal saline and selenium-enriched hot spring water on experimentally induced rhinosinusitis in rats. The study comprised two control groups (untreated and saline-treated) and three experimental groups of Sprague Dawley rats. The experimental groups received an instillation of lipopolysaccharide (LPS) only, LPS+normal saline (LPS/saline), or LPS+selenium-enriched hot spring water (LPS/selenium). Histopathological changes were identified using hematoxylin-eosin staining. Leakage of exudate was identified using fluorescence microscopy. Microvascular permeability was measured using the Evans blue dye technique. Expression of the Muc5ac gene was measured using reverse transcription-polymerase chain reaction. Mucosal edema and expression of the Muc5ac gene were significantly lower in the LPS/saline group than in the LPS group. Microvascular permeability, mucosal edema, and expression of the Muc5ac gene were significantly lower in the LPS/selenium group than in the LPS group. Mucosal edema was similar in the LPS/selenium group and LPS/saline group, but capillary permeability and Muc5ac expression were lower in the LPS/selenium group. This study shows that normal saline and selenium-enriched hot spring water reduce inflammatory activity and mucus hypersecretion in LPS-induced rhinosinusitis in rats. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Effects of experimentally induced intestinal obstruction on the electrolyte profile in dogs

International Nuclear Information System (INIS)

Dar, E.M.; Khan, M.A.; Mehmood, A.K.

2004-01-01

This study was conducted to quantitatively asses the changes in serum electrolyte profile after experimentally induced upper and lower intestinal obstruction in dogs. Ten dogs of either sex ranging in weight from 20-25 Kg were selected. After thorough physical examination, de-worming and vaccination they were randomly divided into 3 groups. Groups A and B comprised of four animals each while group C had two animals. After preparing the operation site, upper intestinal obstruction was induced in animals of group A and lower intestinal obstruction was induced in all animals of group B through mid line laparotomy under general anesthesia. Animals of group C were kept as control without induction of any obstruction. Proper post-operative care was given to the operated animals. Blood samples were collected from all animals at an interval of 24 hours and evaluated to observe changes in serum sodium, potassium and chloride levels. The results of this study showed marked decline in electrolyte levels in animals of both groups A and B, however this decline was more severe and rapid in group A than group B, while group c acted normally. It can be concluded that upper intestinal obstruction is more fatal in its consequences than lower intestinal obstruction, which is relatively less dangerous in producing its ill effects. (author)

Anti-glaucoma potential of Heliotropium indicum Linn in experimentally-induced glaucoma.

Science.gov (United States)

Kyei, Samuel; Koffuor, George Asumeng; Ramkissoon, Paul; Owusu-Afriyie, Osei

2015-01-01

Heliotropium indicum is used as a traditional remedy for hypertension in Ghana. The aim of the study was to evaluate the anti-glaucoma potential of an aqueous whole plant extract of H. indicum to manage experimentally-induced glaucoma. The percentage change in intraocular pressure (IOP), after inducing acute glaucoma (15 mLkg(-1) of 5 % dextrose, i.v.), in New Zealand White rabbits pretreated with Heliotropium indicum aqueous extract (HIE) (30-300 mgkg(-1)), acetazolamide (5 mgkg(-1)), and normal saline (10 mLkg(-1)) per os were measured. IOPs were also monitored in chronic glaucoma in rabbits (induced by 1 % prednisolone acetate drops, 12 hourly for 21 days) after treatments with the same doses of HIE, acetazolamide, and normal saline for 2 weeks. The anti-oxidant property of the extract was assessed by assaying for glutathione levels in the aqueous humour. Glutamate concentration in the vitreous humour was also determined using ELISA technique. Histopathological assessment of the ciliary bodies was made. The extract significantly reduced intraocular pressure (p ≤ 0.05-0.001) in acute and chronic glaucoma, preserved glutathione levels and glutamate concentration (p ≤ 0.01-0.001). Histological assessment of the ciliary body showed a decrease in inflammatory infiltration in the extract and acetazolamide-treated group compared with the normal saline-treated group. The aqueous whole plant extract of Heliotropium indicum has ocular hypotensive, anti-oxidant and possible neuro-protective effects, which therefore underscore its plausible utility as an anti-glaucoma drug with further investigation.

Theoretical and experimental studies of single event effect induced by atmospheric muons on nano-metric technologies

International Nuclear Information System (INIS)

Li Cavoli, P.

2016-01-01

This study concerns the domain of the microelectronics. It consists in the study of the impact of the 3D morphology of the energy deposit on the Single Event Effect (SEE) modeling, induced by atmospheric muons. Over a first phase, the approach has consisted in the modeling of the energy deposit induced by protons in nano-metric volumes. For that purpose the use of the Monte Carlo code GEANT4 has allowed us to simulate and stock in a database the tracks characteristics of the energy deposit induced by protons. Once the approach validated for the protons, simulations of the energy deposit induced by muons have been realized. A CCD camera has been used in order to measure the radiative atmospheric environment and to constrain the modeling of the energy deposit induced by muons. This study highlights and quantify the contribution of the radial distribution of the energy deposit induced by protons in nano-metric volumes for the SEE prediction. On the other hand, the study shows that the contribution of the radial distribution of the energy deposit induced by muons in nano-metric volumes has a negligible impact on the SEE modeling. It will be interesting to realize measurements of the energy deposit induced by muons in nano-metric technologies under particle accelerator. This will allow to bring experimental data still nonexistent necessary to the development of new physical models more accurate on the modeling of the energy deposit induced by muons. (author)

Role of the route of leukotrienes in an experimental model of oral mucositis induced by 5-fluorouracil 1.

Science.gov (United States)

Silva, Viviane Carvalho da; Leitão, Renata Ferreira de Carvalho; Brito, Gerly Anne de Castro; Martins, Conceição da Silva; Freire, Gildenio Estevam; Aragão, Karoline Saboia; Wanderley, Carlos Wagner de Souza; Freitas, Marcos Rabelo de

2017-09-01

To investigate the participation of cysteinyl leukotrienes in the pathophysiology of oral mucositis. Oral mucositis was induced in hamsters using 5-fluorouracil (5-FU; 60 and 40 mg/kg; i.p., on days 1 and 2, respectively, and with excoriations in jugal mucosa on day 4). Montelukast (10, 20, or 40 mg/kg/d; gavage), MK886 (3 mg/kg/d, i.p.), or saline or celecoxib (7.5 mg/kg/d; i.p.) was administered 1 h prior to 5-FU and daily, until the fourth (MK886) or tenth day, when the animals were euthanized and their jugal mucosa was collected for macroscopic, histopathological, and immunohistochemical evaluation. Neither montelukast nor MK-886 prevented the oral mucositis induced by 5-FU, as observed by histopathological evaluation. In addition, we did not find significant differences in the expression of inducible nitric oxide synthase-2, cyclooxygenase-2, or interleukin (IL)-1β between the experimental and control groups. However, we did observe a significant decrease in tumor necrosis factor (TNF)-α expression for all doses of montelukast; we also observed a significant decrease in IL-10 with 40 mg/kg/d and MK 886. Cysteinyl leukotrienes do not play an important role in experimental oral mucositis induced by 5-FU. There is a modulating action specifically on TNF-α.

Neuroprotective and antioxidant effects of Thalassia testudinum extract BM-21, against acrylamide-induced neurotoxicity in mice

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Roberto Menéndez

2014-06-01

Full Text Available Context: Acrylamide (ACR neurotoxicity is associated with the enhancement of lipid peroxidation and the reduction of the antioxidative capacity distal axon and nerve terminal regions. The aqueous ethanolic extract of the marine plant Thalassia testudinum, named BM-21, have shown antioxidant, anti-inflammatory and analgesic properties. Aims: To determine the neuroprotective and the antioxidant effects of BM-21, standardized to thalassiolin B content (5.8 ± 0.9%, on acrylamide (ACR-induced distal axonopathy in male OF-1 mice. Methods: Animals were administered with ACR (70 mg/kg, s.c., 4 weeks, and BM-21 was co-administered p.o at the doses of 4, 40 and 400 mg/kg. The effect of BM-21 on neurobehavioral indexes (rota-rod test, compound muscle action potential (CMAP of the sciatic nerve and oxidative stress parameters were investigated. Results: BM-21 significantly prevented the neurobehavioral sings of neurotoxicity and the alteration of CMAP amplitude and velocity. The lowest dose (4 mg/kg failed to ameliorate these parameters whereas the highest dose (400 mg/kg was the most active. BM-21 (400 mg/kg significantly restored total hydroperoxides (THP and glutathione (GSH in the sciatic nerve as well as superoxide dismutase (SOD and glutathione peroxidase (GSH-Px activities. Additionally, the extract also modified THP, GSH and the activity of SOD in cerebellum and brain towards the standard values. Conclusions: BM-21 given at doses that prevented ACR-induced neurotoxicity also produced antioxidant effect in the sciatic nerve, cerebellum and brain. Thus, the neuroprotective activity of BM-21 in this model seems to be mediated at least partly by its antioxidative properties.

The defensive effect of benfotiamine in sodium arsenite-induced experimental vascular endothelial dysfunction.

Science.gov (United States)

Verma, Sanjali; Reddy, Krishna; Balakumar, Pitchai

2010-10-01

The present study has been designed to investigate the effect of benfotiamine, a thiamine derivative, in sodium arsenite-induced vascular endothelial dysfunction (VED) in rats. Sodium arsenite (1.5 mg(-1) kg(-1) day(-1) i.p., 2 weeks) was administered in rats to produce VED. The development of VED was assessed by employing isolated aortic ring preparation and estimating the serum and aortic concentrations of nitrite/nitrate. Further, the integrity of vascular endothelium in thoracic aorta was assessed by scanning electron microscopy. Moreover, the oxidative stress was assessed by estimating serum thiobarbituric acid reactive substances (TBARS) and aortic superoxide anion generation. The administration of sodium arsenite markedly produced VED by attenuating acetylcholine-induced endothelium-dependent relaxation, decreasing serum and aortic concentrations of nitrite/nitrate, and impairing the integrity of vascular endothelium. Further, sodium arsenite produced oxidative stress by increasing serum TBARS and aortic superoxide generation. The treatment with benfotiamine (25, 50, and 100 mg(-1) kg(-1) day(-1) p.o.) or atorvastatin (30 mg(-1) kg(-1) day(-1) p.o., a standard agent) prevented sodium arsenite-induced VED and oxidative stress. However, the beneficial effects of benfotiamine in preventing the sodium arsenite-induced VED were attenuated by co-administration with N-omega-nitro-L: -arginine methyl ester (L: -NAME) (25 mg(-1) kg(-1) day(-1), i.p.), an inhibitor of NOS. Thus, it may be concluded that benfotiamine reduces oxidative stress and activates endothelial nitric oxide synthase to enhance the generation and bioavailability of NO and subsequently improves the integrity of vascular endothelium to prevent sodium arsenite-induced experimental VED.

Lipid metabolism in streptozotocin induced experimental diabetes and it’s correction with niacin-oxyethylidendiphosphonatogermanate

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N. V. Kresyun

2017-08-01

Full Text Available Introduction. The development of approaches for effective control of diabetes-induced deterioration of lipid metabolism and plasma glucose level could be implemented by the applying of germanium-contained biologically active substances. Among others such compound as niacin – oxyethylidendiphosphonatogermanate (MIGU-4 should be mentioned, which is able to correct effectively the lipid layers of liver mitochondrial membranes on models of streptozotocin – induced diabetes. Aim. To investigate the dynamic changes of the total cholesterol, total phospholipids level along with their molar ratio; fractions of phospholipids of both erythrocyte membranes and liver mitochondria membranes in experimental diabetes mellitus and to investigate the mentioned indices under conditions of complex correction by MIGU-4 and insulin. Materials and Methods. Diabetes was induced in male Wistar rats with streptozotocin injection (50.0 mg/kg., i. p.. ED50 of MIGU-4 (25.0 mg/kg, i. p. was used. Cellular membranes were obtained from erythrocytes, and mitochondrial membranes were obtained through differential centrifugation of liver tissue. Lipid extracts were isolated from 1 g of erythrocyte mass and from 200 mg of liver tissue; phospholipids fractionation was carried out by method of ascending one-dimensional thin-layer chromatography. Content of certain phospholipids was estimated by method of spots “burning out” using the 72 % chloride acid at 200 0С up to their complete bleaching with the consequent determination of lipids phosphate. The level of total phospholipids was calculated by summing up all fractions content. Results. The total cholesterol level substantially elevated along with the decreasing of phospholipids content in both erythrocyte and mitochondrial membranes obtained from liver tissue in two weeks after experimental streptozotocin diabetes induction in rats. It resulted in an increase of the cholesterol/ phospholipids ratio. These changes

Confabulation versus experimentally induced false memories in Korsakoff patients.

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Van Damme, Ilse; d'Ydewalle, Géry

2010-09-01

The present study focuses on both the clinical symptom of confabulation and experimentally induced false memories in patients suffering from Korsakoff's syndrome. Despite the vast amount of case studies of confabulating patients and studies investigating false memories in the Deese-Roediger-McDermott (DRM) paradigm, the nature of Korsakoff patients' confabulatory behaviour and its association with DRM false memories have been rarely examined. Hence, the first aim of the present study was to evaluate confabulatory responses in a large sample of chronic Korsakoff patients and matched controls by means of the Dalla Barba Confabulation Battery. Second, the association between (provoked) confabulation and the patients' DRM false recognition performance was investigated. Korsakoff patients mainly confabulated in response to questions about episodic memory and questions to which the answer was unknown. A positive association was obtained between confabulation and the tendency to accept unstudied distractor words as being old in the DRM paradigm. On the other hand, there was a negative association between confabulation and false recognition of critical lures. The latter could be attributed to the importance of strategic retrieval at delayed memory testing.

Hypolipidemic Effect of Fenugreek Seeds and its Comparison with Atorvastatin on Experimentally Induced Hyperlipidemia

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Sharma, M. S. [R.N.T. Medical College, Udaipur (India). Dept. of Physiology; Choudhary, P. R. [C.U. Shah Medical College, Surendranagr (India). Dept. of Physiology

2014-08-15

Objective: To determine the hypolipidemic effect of fenugreek (Methi) seeds and its comparison with atorvastatin on experimentally induced hyperlipidemia in rabbits. Study Design: Experimental interventional study. Place and Duration of Study: Department of Physiology, Dr. S. N. Medical College, Jodhpur, Rajasthan, India, from April 2012 to March 2013. Methodology: Twenty, 1 - 2 years old albino rabbits of European Strains were randomly divided into two groups of 10 rabbits each. All were fed pure cholesterol (0.5 g/kg body weight/day) for 4 weeks to induce hyperlipidemia. Group-I comprised of 10 hyperlipidemic rabbits which were fed normal (regular) diet supplemented with 2 ml aqueous emulsified fenugreek seeds powder (500 mg/kg body weight/day) for 4 weeks. Group-II comprised of 10 hyperlipidemic rabbits, which were fed normal (regular) diet supplemented with 2 ml aqueous emulsion of atorvastatin (0.5 mg/kg body weight/day) for 4 weeks. Fasting blood samples were collected two times during experimental period at weeks (4 and 8) and analyzed for serum total cholesterol and triglycerides, using semi-automated chemistry analyzer. HDL-C was determined by precipitation method and LDL-C and VLDL-C were estimated by Friedewalds formula. LDL/HDL ratio and TG/HDL ratios were also calculated. The significance of difference in mean values of both groups (lipid profile) was assessed by independent student's t-test. Results: Atorvastatin showed a more potent hypolipidemic activity. It reduced serum total cholesterol, TG, LDL and VLDLcholesterol, and the atherogenic index (LDL-C/HDL-C; p < 0.001) highly significantly as compared to fenugreek. There was a significant increase of HDL-C (p < 0.01) in group-I as compared to group-II. Conclusion: Fenugreek and atorvastatin both have hypolipidemic activity in rabbits but atorvastatin is more potent than fenugreek seeds powder. (author)

Hypolipidemic Effect of Fenugreek Seeds and its Comparison with Atorvastatin on Experimentally Induced Hyperlipidemia

International Nuclear Information System (INIS)

Sharma, M. S.; Choudhary, P. R.

2014-01-01

Objective: To determine the hypolipidemic effect of fenugreek (Methi) seeds and its comparison with atorvastatin on experimentally induced hyperlipidemia in rabbits. Study Design: Experimental interventional study. Place and Duration of Study: Department of Physiology, Dr. S. N. Medical College, Jodhpur, Rajasthan, India, from April 2012 to March 2013. Methodology: Twenty, 1 - 2 years old albino rabbits of European Strains were randomly divided into two groups of 10 rabbits each. All were fed pure cholesterol (0.5 g/kg body weight/day) for 4 weeks to induce hyperlipidemia. Group-I comprised of 10 hyperlipidemic rabbits which were fed normal (regular) diet supplemented with 2 ml aqueous emulsified fenugreek seeds powder (500 mg/kg body weight/day) for 4 weeks. Group-II comprised of 10 hyperlipidemic rabbits, which were fed normal (regular) diet supplemented with 2 ml aqueous emulsion of atorvastatin (0.5 mg/kg body weight/day) for 4 weeks. Fasting blood samples were collected two times during experimental period at weeks (4 and 8) and analyzed for serum total cholesterol and triglycerides, using semi-automated chemistry analyzer. HDL-C was determined by precipitation method and LDL-C and VLDL-C were estimated by Friedewalds formula. LDL/HDL ratio and TG/HDL ratios were also calculated. The significance of difference in mean values of both groups (lipid profile) was assessed by independent student's t-test. Results: Atorvastatin showed a more potent hypolipidemic activity. It reduced serum total cholesterol, TG, LDL and VLDLcholesterol, and the atherogenic index (LDL-C/HDL-C; p < 0.001) highly significantly as compared to fenugreek. There was a significant increase of HDL-C (p < 0.01) in group-I as compared to group-II. Conclusion: Fenugreek and atorvastatin both have hypolipidemic activity in rabbits but atorvastatin is more potent than fenugreek seeds powder. (author)

Trust and Cheating in Sri Lanka: The Role of Experimentally-Induced Emotions about Tsunam

OpenAIRE

Pierluigi Conzo

2014-01-01

Through a field experiment in Sri Lanka I analyze the role of experimentally-induced memories of 2004 tsunami on behavior in a trust game in which personal notions of cheating are elicited. Microfinance borrowers were randomly assigned to a treatment (control) group consisting in watching a video about the calamity before (after) playing. Trust game participants were asked how much to receive (return) in order not to (make the counterpart) feel cheated; in a survey they selected whether the v...

Immunologic responses in corn snakes (Pantherophis guttatus) after experimentally induced infection with ferlaviruses.

Science.gov (United States)

Neul, Annkatrin; Schrödl, Wieland; Marschang, Rachel E; Bjick, Tina; Truyen, Uwe; von Buttlar, Heiner; Pees, Michael

2017-04-01

OBJECTIVE To measure immunologic responses of snakes after experimentally induced infection with ferlaviruses. ANIMALS 42 adult corn snakes (Pantherophis guttatus) of both sexes. PROCEDURES Snakes were inoculated intratracheally with genogroup A (n = 12), B (12), or C (12) ferlavirus (infected groups) or cell-culture supernatant (6; control group) on day 0. Three snakes from each infected group were euthanized on days 4, 16, 28, and 49, and 3 snakes from the control group were euthanized on day 49. Blood samples were collected from live snakes on days -6 (baseline), 4, 16, 28, and 49. Hematologic tests were performed and humoral responses assessed via hemagglutination-inhibition assays and ELISAs. Following euthanasia, gross pathological and histologic evaluations and virus detection were performed. RESULTS Severity of clinical signs of and immunologic responses to ferlavirus infection differed among snake groups. Hematologic values, particularly WBC and monocyte counts, increased between days 4 and 16 after infection. A humoral response was identified between days 16 and 28. Serum IgM concentrations increased from baseline earlier than IgY concentrations, but the IgY relative increase was higher at the end of the study. The hemagglutination-inhibition assay revealed that the strongest reactions in all infected groups were against the strain with which they had been infected. Snakes infected with genogroup A ferlavirus had the strongest immune response, whereas those infected with genogroup B had the weakest responses. CONCLUSIONS AND CLINICAL RELEVANCE Results of this experimental study suggested that the ferlavirus strain with the highest virulence induced the weakest immune response in snakes.

Evaluation of safety and protective effects of Potentilla fulgens root extract in experimentally induced diarrhoea in mice

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V. Tangpu

2014-06-01

Methods: The protective effects of P. fulgens root extract was investigated against experimentally induced diarrhoea in mice, using four experimental models, i.e. measurement of faecal output, castor oil model, prostaglandin E2 (PGE2 enteropooling assay and gastrointestinal transit test. The safety assessment of root extract was done in mice on the basis of general signs and symptoms of toxicity, food water intake and mortality of animals following their treatment with various doses of extract (100 and ndash;3200 mg/kg. In addition, the serum glutamate oxaloacetate transaminase (SGOT, serum glutamate pyruvate transaminase (SGPT, cholesterol and total protein of experimental mice were also monitored to assess the toxicity of root extract. Results: In the safety assessment studies, P. fulgens root extract did not showed any visible signs of toxicity, but mortality was observed in a single animal at 3200 mg/kg dose of extract. The extract also did not showed any adverse effects on the studied serum parameters of experimental animals. In the antidiarrhoeal tests, administration of 800 mg/kg dose of extract to mice showed 50% protection from diarrhoea evoked by castor oil. In addition, the extract also showed 29.27% reduction in PGE2-induced intestinal secretion as compared to 30.31% recorded for loperamide, a standard anti-diarrhoeal drug. Conclusions: The results of this study indicate that P. fulgens root extract possesses significant anti-diarrhoeal properties. Therefore, the roots of this plant can be an effective traditional medicine for the protection from diarrhoea. [J Intercult Ethnopharmacol 2014; 3(3.000: 103-108

An Experimental Study on the Wind-Induced Response of Variable Message Signs

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Debbie Meyer

2017-11-01

Full Text Available Variable message sign (VMS systems are widely used in motorways to provide traffic information to motorists. Such systems are subjected to wind-induced structural vibration that can lead to damage due to fatigue. The limited information that is available on the safe wind design of VMS motivated a large scale testing that was conducted at the wall of wind (WOW Experimental Facility at Florida International University (FIU. One of the objectives of the present study was to experimentally assess the wind-induced force coefficients on VMS of different geometries and utilize these results to provide improved design guidelines. A comprehensive range of VMS geometries was tested, and mean normal and lateral force coefficients, in addition to the twisting moment coefficient and eccentricity ratio, were determined using the measured data for each model, for wind directions of 0° and 45°. The results confirmed that the mean drag coefficient on a prismatic VMS is smaller than the value of 1.7 suggested by American Association of State Highway and Transportation Officials (AASHTO. An alternative to this value is presented in the form of a design matrix with coefficients ranging from 0.98 to 1.28, depending on the aspect and depth ratio of the VMS. Furthermore, results indicated that the corner modification on a VMS with chamfered edges demonstrated a reduction in the drag coefficient compared to sharper edges. Finally, the dynamic loading effects were considered by evaluating the gust effect factor, using the ASCE 7 formulations, for various VMS weights and geometries. The findings revealed a wide range of possible gust effect factors, both above and below the current AASHTO specification of 1.14. Future research may include different geometries of VMS and a wider range of wind directions.

Experimental Protoporphyria: Effect of Bile Acids on Liver Damage Induced by Griseofulvin

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María del Carmen Martinez

2015-01-01

Full Text Available The effect of bile acids administration to an experimental mice model of Protoporphyria produced by griseofulvin (Gris was investigated. The aim was to assess whether porphyrin excretion could be accelerated by bile acids treatment in an attempt to diminish liver damage induced by Gris. Liver damage markers, heme metabolism, and oxidative stress parameters were analyzed in mice treated with Gris and deoxycholic (DXA, dehydrocholic (DHA, chenodeoxycholic, or ursodeoxycholic (URSO. The administration of Gris alone increased the activities of glutathione reductase (GRed, superoxide dismutase (SOD, alkaline phosphatase (AP, gamma glutamyl transpeptidase (GGT, and glutathione-S-transferase (GST, as well as total porphyrins, glutathione (GSH, and cytochrome P450 (CYP levels in liver. Among the bile acids studied, DXA and DHA increased PROTO IX excretion, DXA also abolished the action of Gris, reducing lipid peroxidation and hepatic GSH and CYP levels, and the activities of GGT, AP, SOD, and GST returned to control values. However, porphyrin accumulation was not prevented by URSO; instead this bile acid reduced ALA-S and the antioxidant defense enzymes system activities. In conclusion, we postulate that DXA acid would be more effective to prevent liver damage induced by Gris.

Experimentally studied laser fluorescence method for remote sensing of plant stress situation induced by improper plants watering

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Yu. V. Fedotov

2014-01-01

Full Text Available Stressful situations of plants can be caused by a lack of nutrients; mechanical damages; diseases; low or high temperatures; lack of illumination; insufficient or excess humidity of the soil; soil salinization; soil pollution by oil products or heavy metals; the increased acidity of the soil; use of pesticides, herbicides, insecticides, etc.At early stages it is often difficult to detect seemingly that the plants are in stressful situations caused by adverse external factors. However, the fluorescent analysis potentially allows detection of the stressful situations of plants by deformation of laser-induced fluorescence spectra. The paper conducts experimental investigations to learn the capabilities of the laser fluorescent method to monitor plant situations at 532nm wavelength of fluorescence excitation in the stressful situations induced by improper watering (at excess of moisture in the soil and at a lack of moisture.Researches of fluorescence spectra have been conducted using a created laboratory installation. As a source to excite fluorescence radiation the second harmonica of YAG:Nd laser is used. The subsystem to record fluorescence radiation is designed using a polychromator and a highly sensitive matrix detector with the amplifier of brightness.Experimental investigations have been conducted for fast-growing and unpretentious species of plants, namely different sorts of salad.Experimental studies of laser-induced fluorescence spectra of plants for 532nm excitement wavelength show that the impact of stressful factors on a plant due to the improper watering, significantly distorts a fluorescence spectrum of plants. Influence of a stressful factor can be shown as a changing profile of a fluorescence spectrum (an identifying factor, here, is a relationship of fluorescence intensities at two wavelengths, namely 685 nm and 740 nm or (and as a changing level of fluorescence that can be the basis for the laser method for monitoring the plant

Protective effect of curcumin on experimentally induced arthritic rats: detailed histopathological study of the joints and white blood cell count

OpenAIRE

Kamarudin, Taty Anna; Othman, Faizah; Mohd Ramli, Elvy Suhana; Md Isa, Nurismah; Das, Srijit

2012-01-01

Curcuma longa (turmeric) rhizomes contains curcumin, an active compound which possesses anti-inflammatory effects. Collagen-induced arthritis (CIA) is an accepted experimental animal model of rheumatoid arthritis. The present study aimed to observe the histological changes in the joints of experimental arthritic rats treated with curcumin. Twenty four male Sprague-Dawley (approximately 7 weeks-old) rats were randomly divided into four groups. Three groups were immunized with 150 ?g collagen. ...

Animal model of atherosclerosis using rabbit experimentally induced by combination of X-ray and hypercholesterolemia

International Nuclear Information System (INIS)

Ishiyama, Tomotoshi; Sawai, Takashi; Okuma, Tsuneo; Mori, Shozo

1995-01-01

An attempt was made to prepare an animal model of atherosclerosis similar to human lesions. The experimental animals were male Japanese white rabbits weighting about 2 kg. Hypercholesterolemia was experimentally induced by giving a 1% cholesterol diet. Four weeks later, a single dose of 45 Gy was delivered to the femur to produce vascular changes. Soon after irradiation, immunohistochemical examination revealed the adhesion and invasion of macrophages to endothelial cells, followed by accumulation of foam cells and thickness of the intimal plaques. Three months after irradiation, these thickened plaques became fibrotic, calcified, and necrotic. The tunica media was thinned and the internal elastic lamella was destroyed. Irradiated arteries exhibited not only severe narrowing of the lumen but also aneurysmal dilation and the lesions of the irradiated arteries resembled human atherosclerosis. In conclusion, the atherosclerotic model produced by combining experimental hypercholesterolemia and X-ray irradiaiton may serve as a useful model for studies on atherosclerosis because it can be prepared with no need of complicated or time-consuming procedures. (N.K.)

Experimental Research of Reliability of Plant Stress State Detection by Laser-Induced Fluorescence Method

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Yury Fedotov

2016-01-01

Full Text Available Experimental laboratory investigations of the laser-induced fluorescence spectra of watercress and lawn grass were conducted. The fluorescence spectra were excited by YAG:Nd laser emitting at 532 nm. It was established that the influence of stress caused by mechanical damage, overwatering, and soil pollution is manifested in changes of the spectra shapes. The mean values and confidence intervals for the ratio of two fluorescence maxima near 685 and 740 nm were estimated. It is presented that the fluorescence ratio could be considered a reliable characteristic of plant stress state.

Impact of field-induced quantum confinement on the onset of tunneling field-effect transistors: Experimental verification

Energy Technology Data Exchange (ETDEWEB)

Smets, Quentin, E-mail: quentin.smets@imec.be; Verreck, Devin; Heyns, Marc M. [Imec, Kapeldreef 75, 3001 Heverlee (Belgium); KULeuven, 3000 Leuven (Belgium); Verhulst, Anne S.; Martens, Koen; Lin, Han Chung; Kazzi, Salim El; Simoen, Eddy; Collaert, Nadine; Thean, Aaron [Imec, Kapeldreef 75, 3001 Heverlee (Belgium); Raskin, Jean-Pierre [ICTEAM, Université catholique de Louvain, 1348 Louvain-la-Neuve (Belgium)

2014-11-17

The Tunneling Field-Effect Transistor (TFET) is a promising device for future low-power logic. Its performance is often predicted using semiclassical simulations, but there is usually a large discrepancy with experimental results. An important reason is that Field-Induced Quantum Confinement (FIQC) is neglected. Quantum mechanical simulations show FIQC delays the onset of Band-To-Band Tunneling (BTBT) with hundreds of millivolts in the promising line-TFET configuration. In this letter, we provide experimental verification of this delayed onset. We accomplish this by developing a method where line-TFET are modeled using highly doped MOS capacitors (MOS-CAP). Using capacitance-voltage measurements, we demonstrate AC inversion by BTBT, which was so far unobserved in MOS-CAP. Good agreement is shown between the experimentally obtained BTBT onset and quantum mechanical predictions, proving the need to include FIQC in all TFET simulations. Finally, we show that highly doped MOS-CAP is promising for characterization of traps deep into the conduction band.

Impact of field-induced quantum confinement on the onset of tunneling field-effect transistors: Experimental verification

International Nuclear Information System (INIS)

Smets, Quentin; Verreck, Devin; Heyns, Marc M.; Verhulst, Anne S.; Martens, Koen; Lin, Han Chung; Kazzi, Salim El; Simoen, Eddy; Collaert, Nadine; Thean, Aaron; Raskin, Jean-Pierre

2014-01-01

The Tunneling Field-Effect Transistor (TFET) is a promising device for future low-power logic. Its performance is often predicted using semiclassical simulations, but there is usually a large discrepancy with experimental results. An important reason is that Field-Induced Quantum Confinement (FIQC) is neglected. Quantum mechanical simulations show FIQC delays the onset of Band-To-Band Tunneling (BTBT) with hundreds of millivolts in the promising line-TFET configuration. In this letter, we provide experimental verification of this delayed onset. We accomplish this by developing a method where line-TFET are modeled using highly doped MOS capacitors (MOS-CAP). Using capacitance-voltage measurements, we demonstrate AC inversion by BTBT, which was so far unobserved in MOS-CAP. Good agreement is shown between the experimentally obtained BTBT onset and quantum mechanical predictions, proving the need to include FIQC in all TFET simulations. Finally, we show that highly doped MOS-CAP is promising for characterization of traps deep into the conduction band

Experimental evaluation of the pressure and temperature dependence of ion-induced nucleation.

Science.gov (United States)

Munir, Muhammad Miftahul; Suhendi, Asep; Ogi, Takashi; Iskandar, Ferry; Okuyama, Kikuo

2010-09-28

An experimental system for the study of ion-induced nucleation in a SO(2)/H(2)O/N(2) gas mixture was developed, employing a soft x-ray at different pressure and temperature levels. The difficulties associated with these experiments included the changes in physical properties of the gas mixture when temperature and pressure were varied. Changes in the relative humidity (RH) as a function of pressure and temperature also had a significant effect on the different behaviors of the mobility distributions of particles. In order to accomplish reliable measurement and minimize uncertainties, an integrated on-line control system was utilized. As the pressure decreased in a range of 500-980 hPa, the peak concentration of both ions and nanometer-sized particles decreased, which suggests that higher pressure tended to enhance the growth of particles nucleated by ion-induced nucleation. Moreover, the modal diameters of the measured particle size distributions showed a systematic shift to larger sizes with increasing pressure. However, in the temperature range of 5-20 °C, temperature increases had no significant effects on the mobility distribution of particles. The effects of residence time, RH (7%-70%), and SO(2) concentration (0.08-6.7 ppm) on ion-induced nucleation were also systematically investigated. The results show that the nucleation and growth were significantly dependent on the residence time, RH, and SO(2) concentration, which is in agreement with both a previous model and previous observations. This research will be inevitable for a better understanding of the role of ions in an atmospheric nucleation mechanism.

High-intensity laser therapy during chronic degenerative tenosynovitis experimentally induced in broiler chickens

Science.gov (United States)

Fortuna, Damiano; Rossi, Giacomo; Bilotta, Teresa W.; Zati, Allesandro; Gazzotti, Valeria; Venturini, Antonio; Pinna, Stefania; Serra, Christian; Masotti, Leonardo

2002-10-01

The aims of this study was the safety and the efficacy of High Intensity Laser Therapy (HILT) on chronic degenerative tenosynovitis. We have effectuated the histological evaluation and seroassay (C reactive protein) on 18 chickens affect by chronic degenerative tenosynovitis experimentally induced. We have been employed a Nd:YAG laser pulsed wave; all irradiated subjects received the same total energy (270 Joule) with a fluence of 7,7 J/cm2 and intensity of 10,7 W/cm2. The histological findings revealed a distinct reduction of the mineralization of the choral matrix, the anti-inflammatory effect of the laser, the hyperplasia of the synoviocytes and ectasia of the lymphatic vessels.

Experimental study of stress-induced localized transformation plastic zones in tetragonal zirconia polycrystalline ceramics

International Nuclear Information System (INIS)

Sun, Q.; Zhao, Z.; Chen, W.; Qing, X.; Xu, X.; Dai, F.

1994-01-01

Stress-induced martensitic transformation plastic zones in ceria-stabilized tetragonal zirconia polycrystalline ceramics (Ce-TZP), under loading conditions of uniaxial tension, compression, and three-point bending, are studied by experiments. The transformed monoclinic phase volume fraction distribution and the corresponding plastic strain distribution and the surface morphology (surface uplift) are measured by means of moire interferometry, Raman microprobe spectroscopy, and the surface measurement system. The experimental results from the above three kinds of specimens and methods consistently show that the stress-induced transformation at room temperature of the above specimen is not uniform within the transformation zone and that the plastic deformation is concentrated in some narrow band; i.e., macroscopic plastic flow localization proceeds during the initial stage of plastic deformation. Flow localization phenomena are all observed in uniaxial tension, compression, and three-point bending specimens. Some implications of the flow localization to the constitutive modeling and toughening of transforming thermoelastic polycrystalline ceramics are explored

Experimentally induced acute uric acid nephropathy in rabbits: Findings of high resolution gray scale and doppler ultrasonographies

Energy Technology Data Exchange (ETDEWEB)

Yang, Ik; Chung, Soo Young; Lee, Kyung Won; Kim, Hong Dae; Ko, Eun Young; Won, Mi Sook; Noh, Jung Woo [Hallym University College of Medicine, Seoul (Korea, Republic of); Park, Moon Hyang [Hanyang University College of Medicine, Seoul (Korea, Republic of)

2001-12-15

To evaluate changes of the high-resolution (HR) gray scale and doppler ultrasonographic (US) characteristics of experimentally induced acute uric acid (UA) nephropathy in rabbits. Acute UA nephropathy was induced in ten rabbits using supersaturated lithium carbonate solution. The rabbits were divided in two groups. Group I consisted of five rabbits, and they were injected with a single dose of 150 ml of saturated UA over one hour. During tis period, serial US studies of the kidneys of these rabbits were performed every ten minutes. Group II consisted of the remaining five rabbits, and three injections of 50 ml of saturated UA solution were given on the first, fifth and eight day and follow-up was done upto twenty fifth day. Sequential HR and Doppler US, renal biopsy and blood sampling were performed on day 1, 5, 8, 21, and 25 in the group II rabbits. In group I, HR and Doppler US examination revealed the normal resistive index without significant abnormality. On the other hand, US studies of group II showed poor renal corticomedullary differentiation, decreased renal blood flow and elevated resistive index. There was statistically significant correlation among US findings, histologic characteristics and chemical index (BUN, creatinine) of renal function. In addition, sequentially increased size and volume of the kidney were noted in both groups. HR gray scale and doppler US characteristics of experimentally induced acute UA nephropathy in rabbits were similar to those of acute renal failure caused by other well-known causes.

Experimentally induced acute uric acid nephropathy in rabbits: Findings of high resolution gray scale and doppler ultrasonographies

International Nuclear Information System (INIS)

Yang, Ik; Chung, Soo Young; Lee, Kyung Won; Kim, Hong Dae; Ko, Eun Young; Won, Mi Sook; Noh, Jung Woo; Park, Moon Hyang

2001-01-01

To evaluate changes of the high-resolution (HR) gray scale and doppler ultrasonographic (US) characteristics of experimentally induced acute uric acid (UA) nephropathy in rabbits. Acute UA nephropathy was induced in ten rabbits using supersaturated lithium carbonate solution. The rabbits were divided in two groups. Group I consisted of five rabbits, and they were injected with a single dose of 150 ml of saturated UA over one hour. During tis period, serial US studies of the kidneys of these rabbits were performed every ten minutes. Group II consisted of the remaining five rabbits, and three injections of 50 ml of saturated UA solution were given on the first, fifth and eight day and follow-up was done upto twenty fifth day. Sequential HR and Doppler US, renal biopsy and blood sampling were performed on day 1, 5, 8, 21, and 25 in the group II rabbits. In group I, HR and Doppler US examination revealed the normal resistive index without significant abnormality. On the other hand, US studies of group II showed poor renal corticomedullary differentiation, decreased renal blood flow and elevated resistive index. There was statistically significant correlation among US findings, histologic characteristics and chemical index (BUN, creatinine) of renal function. In addition, sequentially increased size and volume of the kidney were noted in both groups. HR gray scale and doppler US characteristics of experimentally induced acute UA nephropathy in rabbits were similar to those of acute renal failure caused by other well-known causes.

Changes in thermal nociceptive responses in dairy cows following experimentally induced Escherichia coli mastitis

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Klaas Ilka C

2011-05-01

Full Text Available Abstract Background Mastitis is a high incidence disease in dairy cows. The acute stage is considered painful and inflammation can lead to hyperalgesia and thereby contribute to decreased welfare. The aim of this study was to examine changes in nociceptive responses toward cutaneous nociceptive laser stimulation (NLS in dairy cows with experimentally induced Escherichia coli mastitis, and correlate behavioral changes in nociceptive responses to clinical and paraclinical variables. Methods Seven Danish Holstein-Friesian cows were kept in tie-stalls, where the E. coli associated mastitis was induced and laser stimulations were conducted. Measurements of rectal temperature, somatic cell counts, white blood cell counts and E. coli counts were conducted. Furthermore, scores were given for anorexia, local udder inflammation and milk appearance to quantify the local and systemic disease response. In order to quantify the nociceptive threshold, behavioral responses toward cutaneous NLS applied to six skin areas at the tarsus/metatarsus and udder hind quarters were registered at evening milking on day 0 (control and days 1, 2, 3, 6 and 10 after experimental induction of mastitis. Results All clinical and paraclinical variables were affected by the induced mastitis. All cows were clinically ill on days 1 and 2. The cows responded behaviorally toward the NLS. For hind leg stimulation, the proportion of cows responding by stepping was higher on day 0 than days 3 and 6, and the frequency of leg movements after laser stimulation tended to decrease on day 1 compared to the other days. After udder stimulation, the proportion of cows responding by stepping was higher on day 1 than on all other days of testing. Significant correlations between the clinical and paraclinical variables of disease and the behavioral responses toward nociceptive stimulation were found. Conclusions Changes in behavioral responses coincide with peaks in local and systemic signs of E

Kainic Acid-Induced Excitotoxicity Experimental Model: Protective Merits of Natural Products and Plant Extracts

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Nur Shafika Mohd Sairazi

2015-01-01

Full Text Available Excitotoxicity is well recognized as a major pathological process of neuronal death in neurodegenerative diseases involving the central nervous system (CNS. In the animal models of neurodegeneration, excitotoxicity is commonly induced experimentally by chemical convulsants, particularly kainic acid (KA. KA-induced excitotoxicity in rodent models has been shown to result in seizures, behavioral changes, oxidative stress, glial activation, inflammatory mediator production, endoplasmic reticulum stress, mitochondrial dysfunction, and selective neurodegeneration in the brain upon KA administration. Recently, there is an emerging trend to search for natural sources to combat against excitotoxicity-associated neurodegenerative diseases. Natural products and plant extracts had attracted a considerable amount of attention because of their reported beneficial effects on the CNS, particularly their neuroprotective effect against excitotoxicity. They provide significant reduction and/or protection against the development and progression of acute and chronic neurodegeneration. This indicates that natural products and plants extracts may be useful in protecting against excitotoxicity-associated neurodegeneration. Thus, targeting of multiple pathways simultaneously may be the strategy to maximize the neuroprotection effect. This review summarizes the mechanisms involved in KA-induced excitotoxicity and attempts to collate the various researches related to the protective effect of natural products and plant extracts in the KA model of neurodegeneration.

Interleukin 1-induced augmentation of experimental metastases from a human melanoma in nude mice

International Nuclear Information System (INIS)

Giavazzi, R.; Garofalo, A.; Bani, M.R.; Abbate, M.; Ghezzi, P.; Boraschi, D.; Mantovani, A.; Dejana, E.

1990-01-01

This study has examined the effect of the cytokine interleukin 1 (IL-1) on metastasis formation by the human melanoma A375M in nude mice. We have found that human recombinant IL-1 beta (a single injection greater than 0.01 micrograms per mouse i.v. given before tumor cells) induced an augmentation of experimental lung metastases from the A375M tumor cells in nude mice. This effect was rapidly induced and reversible within 24 h after IL-1 injection. A similar effect was induced by human recombinant IL-1 alpha and human recombinant tumor necrosis factor, but not by human recombinant interleukin 6. 5-[125I]odo-2'-deoxyuridine-radiolabeled A375M tumor cells injected i.v. remained at a higher level in the lungs of nude mice receiving IL-1 than in control mice. In addition, IL-1 injected 1 h, but not 24 h, after tumor cells enhanced lung colonization as well, thus suggesting an effect of IL-1 on the vascular transit of tumor cells. These findings may explain the observation of enhanced secondary localization of tumor cells at inflammatory sites and suggest that modulation of secondary spread should be carefully considered when assessing the ability of this cytokine to complement cytoreductive therapies

Assessment of efficacy of polaprezinc suppositories against radiation-induced rectal disorders using an experimental rat model

International Nuclear Information System (INIS)

Doi, Hiroshi; Kamikonya, Norihiko; Takada, Yasuhiro

2009-01-01

The purpose/objective of this study was to establish an experimental rat model and examine the efficacy of polaprezinc suppositories against radiation-induced rectal disorders. Female Wister rats (6 weeks old) were used in the present study. The rats were divided into three groups. Group A was irradiated and medicated with polaprezinc suppositories. Group B was irradiated without any medication. Group C had no irradiation or medication. The rat was taped by the tail in the vertical position under anesthesia. Lead shielding was used to cover the rats except the area of the lower pelvis. They were irradiated at 22 Gy by a single fraction. Polaprezinc suppositories were inserted daily into the rat anus for 7 days after irradiation. All rats were evaluated by colonoscopy on the 7th day after irradiation, sacrificed on the 10th day, and evaluated for mucosal damage. In the clinical findings, the endoscopic findings, and the histological findings, the rats not administered polaprezinc suppositories tended to show more severe mucosal damage but there were no significant differences. Our study showed that this model was a useful experimental rat model for radiation-induced rectal disorders and polaprezinc suppositories demonstrated good efficacy against radiation proctitis. (author)

Molecular analysis of radiation-induced experimental tumors in mice

International Nuclear Information System (INIS)

Niwa, O.; Muto, M.; Suzuki, F.

1992-01-01

Molecular analysis was made on mouse tumors induced by radiation and chemicals. Expression of oncogenes was studied in 12 types of 178 mouse tumors. Southern blotting was done on tumors in which overexpression of oncogenes was noted. Amplification of the myc oncogene was found in chemically induced sarcomas, but not those induced by radiations. Radiogenic thymomas were studied in detail. These thymomas were induced in two different ways. The first was thymomas induced by direct irradiation of F1 mice between C57BL/6NxC3H/He. Southern analysis of DNA revealed deletion of specific minisatellite bands in these tumors. DNA from directly induced thymomas induced focus formation when transfected into normal Golden hamster cells. The mouse K-ras oncogene was detected in these transformants. The second type of thymomas was induced by X-irradiation of thymectomized B10.thy1.2 mice in which normal thymus from congenic B10,thy1.1. mice was grafted. Thymomas of the donor origin was analysed by transfection and the transformants by DNA from those indirectly induced thymomas did not contain activated ras oncogenes. (author)

Antiinflammatory effects of Cordia myxa fruit on experimentally induced colitis in rats.

Science.gov (United States)

Al-Awadi, F M; Srikumar, T S; Anim, J T; Khan, I

2001-05-01

Products of certain species of Cordia are reported to have antiinflammatory properties. In the present study we examined the effects of Cordia myxa fruit on experimentally induced colitis in rats. Colitis was induced by intrarectal administration of 4% acetic acid. Colitic, normal, and corresponding control animals were included. Body weight was recorded daily. All the animals were sacrificed 4 days after the fruit treatment. Colitis was monitored histologically and by activity of myeloperoxidase. Glutathione peroxidase, superoxide dismutase, as well as total antioxidant status and concentrations of zinc, copper, manganese, selenium, and iron were assayed in plasma, liver, and colon using standard methods. Histology of the colon of colitic rats showed acute colitis that was confirmed by a significant increase in the myeloperoxidase activity. Colitis was associated with significant decreases in the tissue activities of glutathione peroxidase and superoxide dismutase and lower concentrations of trace elements. Histologic examination and myeloperoxidase activity showed that the fruit treatment reversed the above findings in the inflamed colon, and in liver and plasma of colitic rats. The present results suggest that the observed antiinflammatory effect of the Cordia myxa may be attributed partly to its antioxidant property and to restoration of the levels of trace elements in the inflamed colon, liver, and plasma.

224Ra and 226Ra experimentally induced dental changes in rats

International Nuclear Information System (INIS)

Reichart, P.A.; Althoff, J.; Eckhardt, W.; Rippel, W.

1979-01-01

Sprague-Dawley rats received intragastrically a single dose of 226 Ra or 224 Ra once weekly for 21 weeks. During this period the animals of both groups were thus exposed to comparable doses. After 12 weeks, a shortening of the maxillary incisors was observed, and this progressed during the course of the 55-week experiment. Radiologically, a loss of pulpal transparency and an apical irregular opacity in the maxillary incisors were demonstrable. Histologically, dysplastic changes of the maxillary incisors and multiple resorptions at the cemento-enamel junction of the molars were seen. The observed alterations were more pronounced in the 226 Ra group than in the 224 Ra treated group. The experimentally induced resorptions were comparable to those observed in patients who had incorporated 224 Ra or 226 Ra. Clinical, radiological, histological, γspecrometrical, and autoradiographical findings, as well as dose-estimations, are described. (author)

Laser-induced interactions

International Nuclear Information System (INIS)

Green, W.R.

1979-01-01

This dissertation discusses some of the new ways that lasers can be used to control the energy flow in a medium. Experimental and theoretical considerations of the laser-induced collision are discussed. The laser-induced collision is a process in which a laser is used to selectively transfer energy from a state in one atomic or molecular species to another state in a different species. The first experimental demonstration of this process is described, along with later experiments in which lasers were used to create collisional cross sections as large as 10 - 13 cm 2 . Laser-induced collisions utilizing both a dipole-dipole interaction and dipole-quadrupole interaction have been experimentally demonstrated. The theoretical aspects of other related processes such as laser-induced spin-exchange, collision induced Raman emission, and laser-induced charge transfer are discussed. Experimental systems that could be used to demonstrate these various processes are presented. An experiment which produced an inversion of the resonance line of an ion by optical pumping of the neutral atom is described. This type of scheme has been proposed as a possible method for constructing VUV and x-ray lasers

Laser-induced damage in dielectrics with nanosecond to subpicosecond pulses. I. Experimental. Part 1

International Nuclear Information System (INIS)

Stuart, B.C.; Herman, S.; Perry, M.D.

1994-12-01

The authors report extensive laser-induced damage threshold measurements on pure and multilayer dielectrics at 1053 and 526 mm for pulse durations, τ, ranging from 140 fs to 1 ns. Qualitative differences in the morphology of damage and a departure from the diffusion-dominated τ 1/2 scaling indicate that damage results from plasma formation and ablation for τ≤10 ps and from conventional melting and boiling for τ>50 ps. A theoretical model based on electron production via multiphoton ionization, Joule heating, and collisional (avalanche) ionization is in good agreement with both the pulsewidth and wavelength scaling of experimental results

Experimental autoimmune prostatitis induces microglial activation in the spinal cord.

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Wong, Larry; Done, Joseph D; Schaeffer, Anthony J; Thumbikat, Praveen

2015-01-01

The pathogenesis of chronic prostatitis/chronic pelvic pain syndrome is unknown and factors including the host's immune response and the nervous system have been attributed to the development of CP/CPPS. We previously demonstrated that mast cells and chemokines such as CCL2 and CCL3 play an important role in mediating prostatitis. Here, we examined the role of neuroinflammation and microglia in the CNS in the development of chronic pelvic pain. Experimental autoimmune prostatitis (EAP) was induced using a subcutaneous injection of rat prostate antigen. Sacral spinal cord tissue (segments S14-S5) was isolated and utilized for immunofluorescence or QRT-PCR analysis. Tactile allodynia was measured at baseline and at various points during EAP using Von Frey fibers as a function for pelvic pain. EAP mice were treated with minocycline after 30 days of prostatitis to test the efficacy of microglial inhibition on pelvic pain. Prostatitis induced the expansion and activation of microglia and the development of inflammation in the spinal cord as determined by increased expression levels of CCL3, IL-1β, Iba1, and ERK1/2 phosphorylation. Microglial activation in mice with prostatitis resulted in increased expression of P2X4R and elevated levels of BDNF, two molecular markers associated with chronic pain. Pharmacological inhibition of microglia alleviated pain in mice with prostatitis and resulted in decreased expression of IL-1β, P2X4R, and BDNF. Our data show that prostatitis leads to inflammation in the spinal cord and the activation and expansion of microglia, mechanisms that may contribute to the development and maintenance of chronic pelvic pain. © 2014 Wiley Periodicals, Inc.

Experimental Neuromyelitis Optica Induces a Type I Interferon Signature in the Spinal Cord

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Kaufmann, Nathalie; Zeka, Bleranda; Schanda, Kathrin; Fujihara, Kazuo; Illes, Zsolt; Dahle, Charlotte; Reindl, Markus; Lassmann, Hans; Bradl, Monika

2016-01-01

Neuromyelitis optica (NMO) is an acute inflammatory disease of the central nervous system (CNS) which predominantly affects spinal cord and optic nerves. Most patients harbor pathogenic autoantibodies, the so-called NMO-IgGs, which are directed against the water channel aquaporin 4 (AQP4) on astrocytes. When these antibodies gain access to the CNS, they mediate astrocyte destruction by complement-dependent and by antibody-dependent cellular cytotoxicity. In contrast to multiple sclerosis (MS) patients who benefit from therapies involving type I interferons (I-IFN), NMO patients typically do not profit from such treatments. How is I-IFN involved in NMO pathogenesis? To address this question, we made gene expression profiles of spinal cords from Lewis rat models of experimental neuromyelitis optica (ENMO) and experimental autoimmune encephalomyelitis (EAE). We found an upregulation of I-IFN signature genes in EAE spinal cords, and a further upregulation of these genes in ENMO. To learn whether the local I-IFN signature is harmful or beneficial, we induced ENMO by transfer of CNS antigen-specific T cells and NMO-IgG, and treated the animals with I-IFN at the very onset of clinical symptoms, when the blood-brain barrier was open. With this treatment regimen, we could amplify possible effects of the I-IFN induced genes on the transmigration of infiltrating cells through the blood brain barrier, and on lesion formation and expansion, but could avoid effects of I-IFN on the differentiation of pathogenic T and B cells in the lymph nodes. We observed that I-IFN treated ENMO rats had spinal cord lesions with fewer T cells, macrophages/activated microglia and activated neutrophils, and less astrocyte damage than their vehicle treated counterparts, suggesting beneficial effects of I-IFN. PMID:26990978

Effects of Schizolobium parahyba extract on experimental Bothrops venom-induced acute kidney injury.

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Monique Silva Martines

Full Text Available BACKGROUND: Venom-induced acute kidney injury (AKI is a frequent complication of Bothrops snakebite with relevant morbidity and mortality. The aim of this study was to assess the effects of Schizolobium parahyba (SP extract, a natural medicine with presumed anti-Bothrops venom effects, in an experimental model of Bothrops jararaca venom (BV-induced AKI. METHODOLOGY: Groups of 8 to 10 rats received infusions of 0.9% saline (control, C, SP 2 mg/kg, BV 0.25 mg/kg and BV immediately followed by SP (treatment, T in the doses already described. After the respective infusions, animals were assessed for their glomerular filtration rate (GFR, inulin clearance, renal blood flow (RBF, Doppler, blood pressure (BP, intra-arterial transducer, renal vascular resistance (RVR, urinary osmolality (UO, freezing point, urinary neutrophil gelatinase-associated lipocalin (NGAL, enzyme-linked immunosorbent assay [ELISA], lactate dehydrogenase (LDH, kinetic method, hematocrit (Hct, microhematocrit, fibrinogen (Fi, Klauss modified and blinded renal histology (acute tubular necrosis score. PRINCIPAL FINDINGS: BV caused significant decreases in GFR, RBF, UO, HcT and Fi; significant increases in RVR, NGAL and LDH; and acute tubular necrosis. SP did not prevent these changes; instead, it caused a significant decrease in GFR when used alone. CONCLUSION: SP administered simultaneously with BV, in an approximate 10∶1 concentration, did not prevent BV-induced AKI, hemolysis and fibrinogen consumption. SP used alone caused a decrease in GFR.

Effect of Gmelina arborea Roxb in experimentally induced inflammation and nociception

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Yogesh A Kulkarni

2013-01-01

Full Text Available Background: Gmelina arborea Roxb (Verbenaceae, also known as "Gambhari", is an important medicinal plant in the Ayurveda. There are no meticulous scientific reports on effect of the plant on inflammation and pain. Objective: To study the anti-inflammatory and anti-nociceptive properties of aqueous extracts (AE and methanol extracts (ME of G. arborea. Materials and Methods: The AE and ME of stembark of G. arborea was prepared by cold maceration and Soxhlet extraction technique respectively. Anti-inflammatory activity was determined in Wistar albino rats in a model of acute plantar inflammation induced by carrageenan. The anti-nociceptive activity was evaluated by using hot plate test and writhing test in Swiss albino mice. Significant differences between the experimental groups were assessed by analysis of variance. Results: AE and ME at dose of 500 mg/kg showed maximum inhibition in carrageenan induced inflammation up to 30.15 and 31.21% respectively. In hot plate test, the AE and ME showed the maximum response of 8.8 ± 0.97 (P < 0.01 and 8.2 ± 1.24 (P < 0.01 respectively at dose of 500 mg/kg when compared with control. AE showed maximum inhibition of writhing response (84.3% as compared to ME (77.9% in writhing test at a dose of 500 mg/kg. Conclusion: The findings suggested that G. arborea possess significant anti-inflammatory and anti-nociceptive activities.

Mechanisms controlling the oxygen consumption in experimentally induced hypochloremic alkalosis in calves.

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Cambier, Carole; Clerbaux, Thierry; Amory, Hélène; Detry, Bruno; Florquin, Sandra; Marville, Vincent; Frans, Albert; Gustin, Pascal

2002-01-01

. It may be concluded that, despite reduced oxygen delivery, oxygen consumption is maintained during experimentally induced hypochloremic alkalosis in healthy 10-30 day old calves.

HYPOLIPEDEMIC EFFECT OF CYNODON DACTYLON ON HISTOPATHOLOGICAL STUDY AND DNA FRAGMENTATION ANALYSIS IN EXPERIMENTALLY INDUCED HYPERCHOLESTEREMIC RATS

OpenAIRE

C. Selva Kumar

2011-01-01

Hypercholesteremia is one of the risk factors for coronary artery disease. The present study highlights the efficacy of Ayurvedic herbal formulation Cynodon dactylon (Bermuda grass) on histopathological study and DNA fragmentation analysis in experimentally induced hypercholesteremic rats. Four groups of rats were employed namely control, hypercholesterolemia rats (4% Cholesterol＋1% cholic acid), Cynodon dactylon treatment in hypercholesteremic rats and Cynodon dactylon alone treated rats. Re...

Minocycline attenuates experimental colitis in mice by blocking expression of inducible nitric oxide synthase and matrix metalloproteinases

International Nuclear Information System (INIS)

Huang, T.-Y.; Chu, H.-C.; Lin, Y.-L.; Lin, C.-K.; Hsieh, T.-Y.; Chang, W.-K.; Chao, Y.-C.; Liao, C.-L.

2009-01-01

In addition to its antimicrobial activity, minocycline exerts anti-inflammatory effects in several disease models. However, whether minocycline affects the pathogenesis of inflammatory bowel disease has not been determined. We investigated the effects of minocycline on experimental colitis and its underlying mechanisms. Acute and chronic colitis were induced in mice by treatment with dextran sulfate sodium (DSS) or trinitrobenzene sulfonic acid (TNBS), and the effect of minocycline on colonic injury was assessed clinically and histologically. Prophylactic and therapeutic treatment of mice with minocycline significantly diminished mortality rate and attenuated the severity of DSS-induced acute colitis. Mechanistically, minocycline administration suppressed inducible nitric oxide synthase (iNOS) expression and nitrotyrosine production, inhibited proinflammatory cytokine expression, repressed the elevated mRNA expression of matrix metalloproteinases (MMPs) 2, 3, 9, and 13, diminished the apoptotic index in colonic tissues, and inhibited nitric oxide production in the serum of mice with DSS-induced acute colitis. In DSS-induced chronic colitis, minocycline treatment also reduced body weight loss, improved colonic histology, and blocked expression of iNOS, proinflammatory cytokines, and MMPs from colonic tissues. Similarly, minocycline could ameliorate the severity of TNBS-induced acute colitis in mice by decreasing mortality rate and inhibiting proinflammatory cytokine expression in colonic tissues. These results demonstrate that minocycline protects mice against DSS- and TNBS-induced colitis, probably via inhibition of iNOS and MMP expression in intestinal tissues. Therefore, minocycline is a potential remedy for human inflammatory bowel diseases.

In vivo evidence for CD4+ and CD8+ suppressor T cells in vaccination-induced suppression of murine experimental autoimmune thyroiditis

International Nuclear Information System (INIS)

Flynn, J.C.; Kong, Y.C.

1991-01-01

In several experimental autoimmune diseases, including experimental autoimmune thyroiditis (EAT), vaccination with attenuated autoantigen-specific T cells has provided protection against subsequent induction of disease. However, the mechanism(s) of vaccination-induced suppression remains to be clarified. Since the authors have previously shown that suppression generated by pretreatment with mouse thyroglobulin (MTg) or thyroid-stimulating hormone in EAT is mediated by CD4+, not CD8+, suppressor T cells, they examined the role of T cell subsets in vaccination-induced suppression of EAT. Mice were vaccinated with irradiated, MTg-primed, and MTg-activated spleen cells and then challenged. Pretreatment with these cells suppressed EAT induced by immunization with MTg and adjuvant, but not by adoptive transfer of thyroiditogenic cells, suggesting a mechanism of afferent suppression. The activation of suppressor mechanisms did not require CD8+ cells, since mice depleted of CD8+ cells before vaccination showed reduced EAT comparable to control vaccinated mice. Furthermore, depletion of either the CD4+ or the CD8+ subset after vaccination did not significantly abrogate suppression. However, suppression was eliminated by the depletion of both CD4+ and CD8+ cells in vaccinated mice. These results provide evidence for the cooperative effects of CD4+ and CD8+ T cells in vaccination-induced suppression of EAT

Complexity of MRI induced heating on metallic leads: Experimental measurements of 374 configurations

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Mendoza Gonzalo

2008-03-01

Full Text Available Abstract Background MRI induced heating on PM leads is a very complex issue. The widely varying results described in literature suggest that there are many factors that influence the degree of heating and that not always are adequately addressed by existing testing methods. Methods We present a wide database of experimental measurements of the heating of metallic wires and PM leads in a 1.5 T RF coil. The aim of these measurements is to systematically quantify the contribution of some potential factors involved in the MRI induced heating: the length and the geometric structure of the lead; the implant location within the body and the lead path; the shape of the phantom used to simulate the human trunk and its relative position inside the RF coil. Results We found that the several factors are the primary influence on heating at the tip. Closer locations of the leads to the edge of the phantom and to the edge of the coil produce maximum heating. The lead length is the other crucial factor, whereas the implant area does not seem to have a major role in the induced temperature increase. Also the lead structure and the geometry of the phantom revealed to be elements that can significantly modify the amount of heating. Conclusion Our findings highlight the factors that have significant effects on MRI induced heating of implanted wires and leads. These factors must be taken into account by those who plan to study or model MRI heating of implants. Also our data should help those who wish to develop guidelines for defining safe medical implants for MRI patients. In addition, our database of the entire set of measurements can help those who wish to validate their numerical models of implants that may be exposed to MRI systems.

Experimental study of microwave-induced thermoacoustic imaging

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Jacobs, Ryan T.

Microwave-Induced Thermoacoustic Imaging (TAI) is a noninvasive hybrid modality which improves contrast by using thermoelastic wave generation induced by microwave absorption. Ultrasonography is widely used in medical practice as a low-cost alternative and supplement to magnetic resonance imaging (MRI). Although ultrasonography has relatively high image resolution (depending on the ultrasonic wavelength at diagnostic frequencies), it suffers from low image contrast of soft tissues. In this work samples are irradiated with sub-microsecond electromagnetic pulses inducing acoustic waves in the sample that are then detected with an unfocused transducer. The advantage of this hybrid modality is the ability to take advantage of the microwave absorption coefficients which provide high contrast in tissue samples. This in combination with the superior spatial resolution of ultrasound waves is important to providing a low-cost alternative to MRI and early breast cancer detection methods. This work describes the implementation of a thermoacoustic experiment using a 5 kW peak power microwave source.

Amelioration of Behavioural, Biochemical, and Neurophysiological Deficits by Combination of Monosodium Glutamate with Resveratrol/Alpha-Lipoic Acid/Coenzyme Q10 in Rat Model of Cisplatin-Induced Peripheral Neuropathy

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Naini Bhadri

2013-01-01

Full Text Available Cisplatin or cis-diamminedichloroplatinum (II (CDDP is a cytotoxic chemotherapeutic agent with dose-dependent peripheral neuropathy as a foremost side effect characterised by ataxia, pain, and sensory impairment. Cumulative drug therapy of CDDP is known to produce severe oxidative damage. It mainly targets and accumulates in dorsal root ganglia that in turn cause damage resulting in secondary nerve fibre axonopathy. In the present study, we investigated the neuroprotective effect of the combination of monosodium glutamate (MSG with three individual antioxidants, that is, resveratrol, alpha-lipoic acid (ALA, and coenzyme Q10 (CoQ10, in cisplatin (2 mg/kg i.p. twice weekly induced peripheral neuropathy in rats. After 8 weeks of treatment the degree of neuroprotection was determined by measuring behavioral and electrophysiological properties and sciatic nerve lipid peroxidation, as well as glutathione and catalase levels. The results suggested that pretreatment with the combination of MSG (500 mg/kg/day po with resveratrol (10 mg/kg/day i.p. or ALA (20 mg/kg/day i.p. or CoQ10 (10 mg/kg weekly thrice i.p. exhibited neuroprotective effect. The maximum neuroprotection of MSG was observed in the combination with resveratrol.

Polymer-coated compliant receivers for intact laser-induced forward transfer of thin films: experimental results and modelling

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Feinaeugle, Matthias; Horak, Peter; Sones, Collin L.; Lippert, Thomas; Eason, Rob W.

2014-09-01

In this study, we investigate both experimentally and numerically laser-induced forward transfer (LIFT) of thin films to determine the role of a thin polymer layer coating the receiver with the aim of modifying the rate of deceleration and reduction of material stress preventing intact material transfer. A numerical model of the impact phase during LIFT shows that such a layer reduces the modelled stress. The evolution of stress within the transferred deposit and the substrate as a function of the thickness of the polymer layer, the transfer velocity and the elastic properties of the polymer are evaluated. The functionality of the polymer layer is verified experimentally by LIFT printing intact 1- m-thick bismuth telluride films and polymeric light-emitting diode pads onto a layer of 12-m-thick polydimethylsiloxane and 50-nm-thick poly(3,4-ethylenedioxythiophene) blended with poly(styrenesulfonate) (PEDOT:PSS), respectively. Furthermore, it is demonstrated experimentally that the introduction of such a compliant layer improves adhesion between the deposit and its substrate.

In vitro and in vivo experimental studies on trabecular meshwork degeneration induced by benzalkonium chloride (an American Ophthalmological Society thesis).

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Baudouin, Christophe; Denoyer, Alexandre; Desbenoit, Nicolas; Hamm, Gregory; Grise, Alice

2012-12-01

Long-term antiglaucomatous drug administration may cause irritation, dry eye, allergy, subconjunctival fibrosis, or increased risk of glaucoma surgery failure, potentially due to the preservative benzalkonium chloride (BAK), whose toxic, proinflammatory, and detergent effects have extensively been shown experimentally. We hypothesize that BAK also influences trabecular meshwork (TM) degeneration. Trabecular specimens were examined using immunohistology and reverse transcriptase-polymerase chain reaction. A trabecular cell line was stimulated by BAK and examined for apoptosis, oxidative stress, fractalkine and SDF-1 expression, and modulation of their receptors. An experimental model was developed with BAK subconjunctival injections to induce TM degeneration. Mass spectrometry (MS) imaging assessed BAK penetration after repeated instillations in rabbit eyes. Trabecular specimens showed extremely low densities of trabecular cells and presence of cells expressing fractalkine and fractalkine receptor and their respective mRNAs. Benzalkonium in vitro induced apoptosis, oxidative stress, and fractalkine expression and inhibited the protective chemokine SDF-1 and Bcl2, also inducing a sustained intraocular pressure (IOP) increase, with dramatic apoptosis of trabecular cells and reduction of aqueous outflow. MS imaging showed that BAK could access the TM at measurable levels after repeated instillations. BAK enhances all characteristics of TM degeneration typical of glaucoma-trabecular apoptosis, oxidative stress, induction of inflammatory chemokines-and causes degeneration in acute experimental conditions, potentially mimicking long-term accumulation. BAK was also shown to access the TM after repeated instillations. These findings support the hypothesis that antiglaucoma medications, through toxicity of their preservative, may cause further long-term trabecular degeneration and therefore enhance outflow resistance, reducing the impact of IOP-lowering agents.

Effects of drug treatment on inflammation and hyperreactivity of airways and on immune variables in cats with experimentally induced asthma.

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Reinero, Carol R; Decile, Kendra C; Byerly, Jenni R; Berghaus, Roy D; Walby, William E; Berghaus, Londa J; Hyde, Dallas M; Schelegle, Edward S; Gershwin, Laurel J

2005-07-01

To compare the effects of an orally administered corticosteroid (prednisone), an inhaled corticosteroid (flunisolide), a leukotriene-receptor antagonist (zafirlukast), an antiserotonergic drug (cyproheptadine), and a control substance on the asthmatic phenotype in cats with experimentally induced asthma. 6 cats with asthma experimentally induced by the use of Bermuda grass allergen (BGA). A randomized, crossover design was used to assess changes in the percentage of eosinophils in bronchoalveolar lavage fluid (BALF); airway hyperresponsiveness; blood lymphocyte phenotype determined by use of flow cytometry; and serum and BALF content of BGA-specific IgE, IgG, and IgA determined by use of ELISAs. Mean +/- SE eosinophil percentages in BALF when cats were administered prednisone (5.0 +/- 2.3%) and flunisolide (2.5 +/- 1.7%) were significantly lower than for the control treatment (33.7 +/- 11.1%). We did not detect significant differences in airway hyperresponsiveness or lymphocyte surface markers among treatments. Content of BGA-specific IgE in serum was significantly lower when cats were treated with prednisone (25.5 +/- 5.4%), compared with values for the control treatment (63.6 +/- 12.9%); no other significant differences were observed in content of BGA-specific immunoglobulins among treatments. Orally administered and inhaled corticosteroids decreased eosinophilic inflammation in airways of cats with experimentally induced asthma. Only oral administration of prednisone decreased the content of BGA-specific IgE in serum; no other significant local or systemic immunologic effects were detected among treatments. Inhaled corticosteroids can be considered as an alternate method for decreasing airway inflammation in cats with asthma.

Experimental Gestational Diabetes Mellitus Induces Blunted Vasoconstriction and Functional Changes in the Rat Aorta

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Cecilia Tufiño

2014-01-01

Full Text Available Diabetic conditions increase vascular reactivity to angiotensin II in several studies but there are scarce reports on cardiovascular effects of hypercaloric diet (HD induced gestational diabetes mellitus (GDM, so the objective of this work was to determine the effects of HD induced GDM on vascular responses. Angiotensin II as well as phenylephrine induced vascular contraction was tested in isolated aorta rings with and without endothelium from rats fed for 7 weeks (4 before and 3 weeks during pregnancy with standard (SD or hypercaloric (HD diet. Also, protein expression of AT1R, AT2R, COX-1, COX-2, NOS-1, and NOS-3 and plasma glucose, insulin, and angiotensin II levels were measured. GDM impaired vasoconstrictor response (P<0.05 versus SD in intact (e+ but not in endothelium-free (e− vessels. Losartan reduced GDM but not SD e− vasoconstriction (P<0.01 versus SD. AT1R, AT2R, and COX-1 and COX-2 protein expression were significantly increased in GDM vessels (P<0.05 versus SD. Results suggest an increased participation of endothelium vasodilator mediators, probably prostaglandins, as well as of AT2 vasodilator receptors as a compensatory mechanism for vasoconstrictor changes generated by experimental GDM. Considering the short term of rat pregnancy findings can reflect early stage GDM adaptations.

Analgesic effects of intramuscular administration of meloxicam in Hispaniolan parrots (Amazona ventralis) with experimentally induced arthritis.

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Cole, Gretchen A; Paul-Murphy, Joanne; Krugner-Higby, Lisa; Klauer, Julia M; Medlin, Scott E; Keuler, Nicholas S; Sladky, Kurt K

2009-12-01

OBJECTIVE-To evaluate the analgesic efficacy of meloxicam in parrots with experimentally induced arthritis, with extent of weight bearing and rotational perch walking used as outcome measures. ANIMALS-15 adult Hispaniolan parrots (Amazona ventralis). PROCEDURES-Arthritis was experimentally induced via intra-articular injection of microcrystalline sodium urate suspension (MSU) into 1 intertarsal joint. Parrots were treated in a crossover design. Five treatments were compared as follows: meloxicam (4 dosages) at 0.05, 0.1, 0.5, and 1.0 mg/kg (IM, q 12 h, 3 times) and 0.03 mL of saline (0.9% NaCl) solution (IM, q 12 h, 3 times). The first treatment was given 6 hours following MSU administration. Lameness was assessed by use of a biomechanical perch to record weight-bearing load and a rotational perch to determine dexterity. Feces were collected to assay for occult blood. RESULTS-Parrots treated with meloxicam at 1.0 mg/kg had significantly better return to normal (baseline) weight bearing on the arthritic pelvic limb, compared with control parrots or parrots treated with meloxicam at 0.05, 0.1, and 0.5 mg/kg. All fecal samples collected from parrots following induction of arthritis and treatment with meloxicam had negative results for occult blood. CONCLUSIONS AND CLINICAL RELEVANCE-Meloxicam administered at 1.0 mg/kg, IM, every 12 hours effectively relieved arthritic pain in parrots.

Immunologic and hematologic responses in ponies with experimentally induced Strongylus vulgaris infection.

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Bailey, M; Martin, S C; Lloyd, S

1989-08-01

Immunologic and hematologic responses were examined in 4 ponies with experimentally induced Strongylus vulgaris infection and in 5 helminth-free ponies. Two ponies were inoculated with 200 larvae and 2 were inoculated with 700 larvae of S vulgaris and then were reinoculated with the same numbers of larvae 34 weeks later. Initial response of the ponies inoculated with S vulgaris was S vulgaris antigen-induced lymphocyte response that developed 1.5 to 3 weeks after inoculation and did not persist. Development of antigen-reactive lymphocytes was followed sequentially by a biphasic complement-fixing antibody response, then biphasic eosinophilia. Antibody titer to S vulgaris antigen was higher in ponies inoculated with 700 larvae, compared with that in ponies given 200 larvae of S vulgaris. Also, the second peak in antibody titer and in absolute number of eosinophils was observed earlier in ponies inoculated with 700 larvae, compared with ponies inoculated with 200 S vulgaris larvae, and subsided before or from about 24 weeks after inoculation. The prepatent period for S vulgaris infection was 24 to 25 weeks. After reinoculation with S vulgaris, a degree of increased lymphocyte responsiveness was apparent but, by 17 weeks after reinoculation, only the primary peak in the absolute number of eosinophils indicated an anamnestic response. Essentially, antibody was not detectable after reinoculation.

Multiple sites and actions of gabapentin-induced relief of ongoing experimental neuropathic pain.

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Bannister, Kirsty; Qu, Chaoling; Navratilova, Edita; Oyarzo, Janice; Xie, Jennifer Yanhua; King, Tamara; Dickenson, Anthony H; Porreca, Frank

2017-12-01

Gabapentin (GBP) is a first-line therapy for neuropathic pain, but its mechanisms and sites of action remain uncertain. We investigated GBP-induced modulation of neuropathic pain following spinal nerve ligation (SNL) in rats. Intravenous or intrathecal GBP reversed evoked mechanical hypersensitivity and produced conditioned place preference (CPP) and dopamine (DA) release in the nucleus accumbens (NAc) selectively in SNL rats. Spinal GBP also significantly inhibited dorsal horn wide-dynamic-range neuronal responses to a range of evoked stimuli in SNL rats. By contrast, GBP microinjected bilaterally into the rostral anterior cingulate cortex (rACC), produced CPP, and elicited NAc DA release selectively in SNL rats but did not reverse tactile allodynia and had marginal effects on wide-dynamic-range neuronal activity. Moreover, blockade of endogenous opioid signaling in the rACC prevented intravenous GBP-induced CPP and NAc DA release but failed to block its inhibition of tactile allodynia. Gabapentin, therefore, can potentially act to produce its pain relieving effects by (a) inhibition of injury-induced spinal neuronal excitability, evoked hypersensitivity, and ongoing pain and (b) selective supraspinal modulation of affective qualities of pain, without alteration of reflexive behaviors. Consistent with previous findings of pain relief from nonopioid analgesics, GBP requires engagement of rACC endogenous opioid circuits and downstream activation of mesolimbic reward circuits reflected in learned pain-motivated behaviors. These findings support the partial separation of sensory and affective dimensions of pain in this experimental model and suggest that modulation of affective-motivational qualities of pain may be the preferential mechanism of GBP's analgesic effects in patients.

Experimentally induced thyrotoxicosis leads to increased connectivity in temporal lobe structures: a resting state fMRI study.

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Göttlich, Martin; Heldmann, Marcus; Göbel, Anna; Dirk, Anna-Luise; Brabant, Georg; Münte, Thomas F

2015-06-01

Adult onset hyperthyroidism may impact on different cognitive domains, including attention and concentration, memory, perceptual function, language and executive function. Previous PET studies implicated changed functionality of limbic regions, the temporal and frontal lobes in hyperthyroidism, whereas it is unknown whether cognitive effects of hyperthyroidism may be due to changed brain connectivity. This study aimed to investigate the effect of experimentally induced short-term hyperthyroidism thyrotoxicosis on resting-state functional connectivity using functional magnetic resonance imaging. Twenty-nine healthy male right-handed subjects were examined twice, once prior and once after 8 weeks of oral administration of 250 μg levothyroxine per day. Resting-state fMRI was subjected to graph-theory based analysis methods to investigate whole-brain intrinsic functional connectivity. Despite a lack of subjective changes noticed by the subjects significant thyrotoxicosis was confirmed in all subjects. This induced a significant increase in resting-state functional connectivity specifically in the rostral temporal lobes (0.05 FDR corrected at the cluster level), which is caused by an increased connectivity to the cognitive control network. The increased connectivity between temporal poles and the cognitive control network shown here under experimental conditions supports an important function of thyroid hormones in the regulation of paralimbic structures. Copyright © 2015 Elsevier Ltd. All rights reserved.

Placebo effect of an inert gel on experimentally induced leg muscle pain

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James G Hopker

2010-11-01

Full Text Available James G Hopker1, Abigail J Foad2, Christopher J Beedie2, Damian A Coleman2, Geoffrey Leach11Centre for Sports Studies, University of Kent, Chatham, Kent, UK; 2Department of Sports Science, Tourism and Leisure, Canterbury Christ Church University, Canterbury, Kent, UKPurpose: This study examined the therapeutic effects of an inert placebo gel on experimentally induced muscle pain in a sports therapy setting. It aimed to investigate the degree to which conditioned analgesia, coupled with an expectation of intervention, was a factor in subsequent analgesia.Methods: Participants were sixteen male and eight female sports therapy students at a UK University. With institutional ethics board approval and following informed consent procedures, each was exposed to pain stimulus in the lower leg in five conditions, ie, conditioning, prebaseline, experimental (two placebo gel applications, and postbaseline. In conditioning trials, participants identified a level of pain stimulus equivalent to a perceived pain rating of 6/10. An inert placebo gel was then applied to the site with the explicit instruction that it was an analgesic. Participants were re-exposed to the pain stimulus, the level of which, without their knowledge, had been decreased, creating the impression of an analgesic effect resulting from the gel. In experimental conditions, the placebo gel was applied and the level of pain stimulus required to elicit a pain rating of 6/10 recorded.Results: Following application of the placebo gel, the level of pain stimulus required to elicit a pain rating of 6/10 increased by 8.2%. Application of the placebo gel significantly decreased participant’s perceptions of muscle pain (P = 0.001.Conclusion: Subjects’ experience and expectation of pain reduction may be major factors in the therapeutic process. These factors should be considered in the sports therapeutic environment.Keywords: conditioning, expectation, perception, positive belief, sports therapy

A three-layer model of self-assembly induced surface-energy variation experimentally extracted by using nanomechanically sensitive cantilevers

International Nuclear Information System (INIS)

Zuo Guomin; Li Xinxin

2011-01-01

This research is aimed at elucidating surface-energy (or interfacial energy) variation during the process of molecule-layer self-assembly on a solid surface. A quasi-quantitative plotting model is proposed and established to distinguish the surface-energy variation contributed by the three characteristic layers of a thiol-on-gold self-assembled monolayer (SAM), namely the assembly-medium correlative gold/head-group layer, the chain/chain interaction layer and the tail/medium layer, respectively. The data for building the model are experimentally extracted from a set of correlative thiol self-assemblies in different media. The variation in surface-energy during self-assembly is obtained by in situ recording of the self-assembly induced nanomechanical surface-stress using integrated micro-cantilever sensors. Based on the correlative self-assembly experiment, and by using the nanomechanically sensitive self-sensing cantilevers to monitor the self-assembly induced surface-stressin situ, the experimentally extracted separate contributions of the three layers to the overall surface-energy change aid a comprehensive understanding of the self-assembly mechanism. Moreover, the quasi-quantitative modeling method is helpful for optimal design, molecule synthesis and performance evaluation of molecule self-assembly for application-specific surface functionalization.

Experimental evaluation of earthquake induced relay chattering

International Nuclear Information System (INIS)

Bandyopadhyay, K.; Hofmayer, C.; Shteyngart, S.

1990-01-01

An experimental evaluation of relay performance under vibratory environments is discussed in this paper. Single frequency excitation was used for most tests. Limited tests were performed with random multifrequency inputs. The capacity of each relay was established based on a two-millisecond chatter criterion. The experimental techniques are described and the effects of parameters in controlling the relay capacity levels are illustrated with test data. A wide variation of the capacity levels was observed due to the influence of parameters related to the design of the relay and nature of the input motion. 3 refs., 15 figs

Toll-like receptors-2 and 4 are overexpressed in an experimental model of particle-induced osteolysis.

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Valladares, Roberto D; Nich, Christophe; Zwingenberger, Stefan; Li, Chenguang; Swank, Katherine R; Gibon, Emmanuel; Rao, Allison J; Yao, Zhenyu; Goodman, Stuart B

2014-09-01

Aseptic loosening secondary to particle-associated periprosthetic osteolysis remains a major cause of failure of total joint replacements (TJR) in the mid- and long term. As sentinels of the innate immune system, macrophages are central to the recognition and initiation of the inflammatory cascade, which results in the activation of bone resorbing osteoclasts. Toll-like receptors (TLRs) are involved in the recognition of pathogen-associated molecular patterns and danger-associated molecular patterns. Experimentally, polymethylmethacrylate and polyethylene (PE) particles have been shown to activate macrophages via the TLR pathway. The specific TLRs involved in PE particle-induced osteolysis remain largely unknown. We hypothesized that TLR-2, -4, and -9 mediated responses play a critical role in the development of PE wear particle-induced osteolysis in the murine calvarium model. To test this hypothesis, we first demonstrated that PE particles caused observable osteolysis, visible by microCT and bone histomorphometry when the particles were applied to the calvarium of C57BL/6 mice. The number of TRAP positive osteoclasts was significantly greater in the PE-treated group when compared to the control group without particles. Finally, using immunohistochemistry, TLR-2 and TLR-4 were highly expressed in PE particle-induced osteolytic lesions, whereas TLR-9 was downregulated. TLR-2 and -4 may represent novel therapeutic targets for prevention of wear particle-induced osteolysis and accompanying TJR failure. © 2013 Wiley Periodicals, Inc.

L-glutamine supplementation prevents the development of experimental diabetic cardiomyopathy in streptozotocin-nicotinamide induced diabetic rats.

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Sachin L Badole

Full Text Available The objective of the present investigation was to evaluate the effect of L-glutamine on cardiac myopathy in streptozotocin-nicotinamide induced diabetic rats. Diabetes was induced in overnight fasted Sprague Dawely rats by using intraperitonial injection of streptozotocin (55 mg/kg. Nicotinamide (100 mg/kg, i.p. was administered 20 min before administration of streptozotocin. Experimental rats were divided into Group I: non-diabetic control (distilled water; 10 ml/kg, p.o., II: diabetic control (distilled water, 10 ml/kg, p.o., III: L-glutamine (500 mg/kg, p.o. and IV: L-glutamine (1000 mg/kg, p.o.. All groups were diabetic except group I. The plasma glucose level, body weight, electrocardiographic abnormalities, hemodynamic changes and left ventricular contractile function, biological markers of cardiotoxicity, antioxidant markers were determined after 4 months after STZ with nicotinamide injection. Histopathological changes of heart tissue were carried out by using H and E stain. L-glutamine treatment improved the electrocardiographic, hemodynamic changes; LV contractile function; biological markers; oxidative stress parameters and histological changes in STZ induced diabetic rats. Results from the present investigation demonstrated that L-glutamine has seemed a cardioprotective activity.

The role of periodontal ASIC3 in orofacial pain induced by experimental tooth movement in rats.

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Gao, Meiya; Long, Hu; Ma, Wenqiang; Liao, Lina; Yang, Xin; Zhou, Yang; Shan, Di; Huang, Renhuan; Jian, Fan; Wang, Yan; Lai, Wenli

2016-12-01

This study aimed to clarify the roles of Acid-sensing ion channel 3 (ASIC3) in orofacial pain following experimental tooth movement. Sixty male Sprague-Dawley rats were divided into the experimental group (40g, n = 30) and the sham group (0g, n = 30). Closed coil springs were ligated between maxillary incisor and molars to achieve experimental tooth movement. Rat grimace scale (RGS) scores were assessed at 0, 1, 3, 5, 7, and 14 days after the placement of the springs. ASIC3 immunostaining was performed and the expression levels of ASIC3 were measured through integrated optical density/area in Image-Pro Plus 6.0. Moreover, 18 rats were divided into APETx2 group (n = 6), amiloride group (n = 6), and vehicle group (n = 6), and RGS scores were obtained compared among them to verify the roles of ASIC3 in orofacial pain following tooth movement. ASIC3 expression levels became significantly higher in the experimental group than in sham group on 1, 3, and 5 days and became similar on 7 and 14 days. Pain levels (RGS scores) increased in both groups and were significantly higher in the experimental group on 1, 3, 5, and 7 days and were similar on 14 days. Periodontal ASIC3 expression levels were correlated with orofacial pain levels following experimental tooth movement. Periodontal administrations of ASIC3 antagonists (APETx2 and amiloride) could alleviate pain. This study needs to be better evidenced by RNA interference of ASIC3 in periodontal tissues in rats following experimental tooth movement. Moreover, we hope further studies would concentrate on the pain perception of ASIC3 knockout (ASIC3 -/- ) mice. Our results suggest that periodontal ASIC3 plays an important role in orofacial pain induced by experimental tooth movement. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

RAE-1 expression is induced during experimental autoimmune encephalomyelitis and is correlated with microglia cell proliferation.

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Djelloul, Mehdi; Popa, Natalia; Pelletier, Florence; Raguénez, Gilda; Boucraut, José

2016-11-01

Retinoic acid early induced transcript-1 (RAE-1) glycoproteins are ligands of the activating immune receptor NKG2D. They are known as stress molecules induced in pathological conditions. We previously reported that progenitor cells express RAE-1 in physiological conditions and we described a correlation between RAE-1 expression and cell proliferation. In addition, we showed that Raet1 transcripts are induced in the spinal cord of experimental autoimmune encephalomyelitis (EAE) mice. EAE is a model for multiple sclerosis which is accompanied by microglia proliferation and activation, recruitment of immune cells and neurogenesis. We herein studied the time course expression of the two members of the Raet1 gene family present in C57BL/6 mice, namely Raet1d and Raet1e, in the spinal cord during EAE. We report that Raet1d and Raet1e genes are induced early upon EAE onset and reach a maximal expression at the peak of the pathology. We show that myeloid cells, i.e. macrophages as well as microglia, are cellular sources of Raet1 transcripts. We also demonstrate that only Raet1d expression is induced in microglia, whereas macrophages expressed both Raet1d and Raet1e. Furthermore, we investigated the dynamics of RAE-1 expression in microglia cultures. RAE-1 induction correlated with cell proliferation but not with M1/M2 phenotypic orientation. We finally demonstrate that macrophage colony-stimulating factor (M-CSF) is a major factor controlling RAE-1 expression in microglia. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of sevoflurane on ventilator induced lung injury in a healthy lung experimental model.

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Romero, A; Moreno, A; García, J; Sánchez, C; Santos, M; García, J

2016-01-01

Ventilator-induced lung injury (VILI) causes a systemic inflammatory response in tissues, with an increase in IL-1, IL-6 and TNF-α in blood and tissues. Cytoprotective effects of sevoflurane in different experimental models are well known, and this protective effect can also be observed in VILI. The objective of this study was to assess the effects of sevoflurane in VILI. A prospective, randomized, controlled study was designed. Twenty female rats were studied. The animals were mechanically ventilated, without sevoflurane in the control group and sevoflurane 3% in the treated group (SEV group). VILI was induced applying a maximal inspiratory pressure of 35 cmH2O for 20 min without any positive end-expiratory pressure for 20 min (INJURY time). The animals were then ventilated 30 min with a maximal inspiratory pressure of 12 cmH2O and 3 cmH2O positive end-expiratory pressure (time 30 min POST-INJURY), at which time the animals were euthanized and pathological and biomarkers studies were performed. Heart rate, invasive blood pressure, pH, PaO2, and PaCO2 were recorded. The lung wet-to-dry weight ratio was used as an index of lung edema. No differences were found in the blood gas analysis parameters or heart rate between the 2 groups. Blood pressure was statistically higher in the control group, but still within the normal clinical range. The percentage of pulmonary edema and concentrations of TNF-α and IL-6 in lung tissue in the SEV group were lower than in the control group. Sevoflurane attenuates VILI in a previous healthy lung in an experimental subclinical model in rats. Copyright © 2015 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

Pumped storage system model and experimental investigations on S-induced issues during transients

Science.gov (United States)

Zeng, Wei; Yang, Jiandong; Hu, Jinhong

2017-06-01

Because of the important role of pumped storage stations in the peak regulation and frequency control of a power grid, pump turbines must rapidly switch between different operating modes, such as fast startup and load rejection. However, pump turbines go through the unstable S region in these transition processes, threatening the security and stability of the pumped storage station. This issue has mainly been investigated through numerical simulations, while field experiments generally involve high risks and are difficult to perform. Therefore, in this work, the model test method was employed to study S-induced security and stability issues for a pumped storage station in transition processes. First, a pumped storage system model was set up, including the piping system, model units, electrical control systems and measurement system. In this model, two pump turbines with different S-shaped characteristics were installed to determine the influence of S-shaped characteristics on transition processes. The model platform can be applied to simulate any hydraulic transition process that occurs in real power stations, such as load rejection, startup, and grid connection. On the experimental platform, the S-shaped characteristic curves were measured to be the basis of other experiments. Runaway experiments were performed to verify the impact of the S-shaped characteristics on the pump turbine runaway stability. Full load rejection tests were performed to validate the effect of the S-shaped characteristics on the water-hammer pressure. The condition of one pump turbine rejecting its load after another defined as one-after-another (OAA) load rejection was performed to validate the possibility of S-induced extreme draft tube pressure. Load rejection experiments with different guide vane closing schemes were performed to determine a suitable scheme to adapt the S-shaped characteristics. Through these experiments, the threats existing in the station were verified, the

Experimentally induced masseter-pain changes masseter but not sternocleidomastoid muscle-related activity during mastication.

Science.gov (United States)

Pasinato, Fernanda; Santos-Couto-Paz, Clarissa C; Zeredo, Jorge Luis Lopes; Macedo, Sergio Bruzadelli; Corrêa, Eliane C R

2016-12-01

The aim of this study was to verify the effects of induced masseter-muscle pain on the amplitude of muscle activation, symmetry and coactivation of jaw- and neck-muscles during mastication. Twenty-eight male volunteers, mean age±SD 20.6±2.0years, participated in this study. Surface electromyography of the masseter and sternocleidomastoid (SCM) muscles was performed bilaterally during mastication of a gummy candy before and after injections of monosodium glutamate solution and isotonic saline solution. As a result, we observed a decrease in the amplitude of activation of the masseter muscle on the working side (p=0.009; d=0.34) and a reduction in the asymmetry between the working and the balancing side during mastication (p=0.007; d=0.38). No changes were observed either on the craniocervical electromyographic variables. In conclusion, experimentally induced pain reduced the masseter muscle activation on the working side, thereby reducing the physiological masseters' recruitment asymmetry between the two sides during mastication. No effects on SCM activity were detected. These results may partly explain the initial maladaptative changes underlying TMD conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Radiation induced currents in mineral-insulated cables and in pick-up coils: model calculations and experimental verification in the BR1 reactor

Science.gov (United States)

Vermeeren, Ludo; Leysen, Willem; Brichard, Benoit

2018-01-01

Mineral-insulated (MI) cables and Low-Temperature Co-fired Ceramic (LTCC) magnetic pick-up coils are intended to be installed in various position in ITER. The severe ITER nuclear radiation field is expected to lead to induced currents that could perturb diagnostic measurements. In order to assess this problem and to find mitigation strategies models were developed for the calculation of neutron-and gamma-induced currents in MI cables and in LTCC coils. The models are based on calculations with the MCNPX code, combined with a dedicated model for the drift of electrons stopped in the insulator. The gamma induced currents can be easily calculated with a single coupled photon-electron MCNPX calculation. The prompt neutron induced currents requires only a single coupled neutron-photon-electron MCNPX run. The various delayed neutron contributions require a careful analysis of all possibly relevant neutron-induced reaction paths and a combination of different types of MCNPX calculations. The models were applied for a specific twin-core copper MI cable, for one quad-core copper cable and for silver conductor LTCC coils (one with silver ground plates in order to reduce the currents and one without such silver ground plates). Calculations were performed for irradiation conditions (neutron and gamma spectra and fluxes) in relevant positions in ITER and in the Y3 irradiation channel of the BR1 reactor at SCK•CEN, in which an irradiation test of these four test devices was carried out afterwards. We will present the basic elements of the models and show the results of all relevant partial currents (gamma and neutron induced, prompt and various delayed currents) in BR1-Y3 conditions. Experimental data will be shown and analysed in terms of the respective contributions. The tests were performed at reactor powers of 350 kW and 1 MW, leading to thermal neutron fluxes of 1E11 n/cm2s and 3E11 n/cm2s, respectively. The corresponding total radiation induced currents are ranging from

Hepatoprotective effect of Solanum xanthocarpum fruit extract against CCl4 induced acute liver toxicity in experimental animals.

Science.gov (United States)

Gupta, Ramesh K; Hussain, Talib; Panigrahi, G; Das, Avik; Singh, Gireesh Narayan; Sweety, K; Faiyazuddin, Md; Rao, Chandana Venkateswara

2011-12-01

To investigate the hepatoprotective potential of Solanum xanthocarpum (Solanaceae) (S. xanthocarpum) in experimental rats to validate its traditional claim. 50% ethanolic fruit extract of S. xanthocarpum (SXE, 100, 200 or 400 mg/kg body weight) was administered daily for 14 days in experimental animals. Liver injury was induced chemically, by CCl(4) administration (1 mL/kg i. p.). The hepatoprotective activity was assessed using various biochemical parameters like aspartate aminotransferase (AST), alanine aminotransferase (ALT), Serum alkaline phosphatise (SALP) and total bilirubin. Meanwhile, in vivo antioxidant activities as lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were screened along with histopathological studies. Obtained results demonstrated that the treatment with SXE significantly (P<0.05-<0.001) and dose-dependently prevented chemically induced increase in serum levels of hepatic enzymes. Furthermore, SXE significantly (up to P<0.001) reduced the lipid peroxidation in the liver tissue and restored activities of defence antioxidant enzymes GSH, SOD and catalase towards normal levels. Histopathology of the liver tissue showed that SXE attenuated the hepatocellular necrosis and led to reduction of inflammatory cells inflltration. The results of this study strongly indicate the protective effect of SXE against acute liver injury which may be attributed to its hepatoprotective activity, and there by scientifically support its traditional use. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Acute pulmonary injury induced by experimental muscle trauma Lesão pulmonar aguda induzida por trauma muscular experimental

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Márcia Andréa da Silva Carvalho Sombra

2011-01-01

Full Text Available PURPOSE: To develop an easily reproducible model of acute lung injury due to experimental muscle trauma in healthy rats. METHODS: Eighteen adult Wistar rats were randomized in 3 groups (n=6: G-1- control, G-2 - saline+trauma and G-3 - dexamethasone+trauma. Groups G-1 and G-2 were treated with saline 2,0ml i.p; G-3 rats were treated with dexamethasone (DE (2 mg/kg body weight i.p.. Saline and DE were applied 2h before trauma and 12h later. Trauma was induced in G-2 and G-3 anesthetized (tribromoethanol 97% 100 ml/kg i.p. rats by sharp section of anterior thigh muscles just above the knee, preserving major vessels and nerves. Tissue samples (lung were collected for myeloperoxidase (MPO assay and histopathological evaluation. RESULTS: Twenty-four hours after muscle injury there was a significant increase in lung neutrophil infiltration, myeloperoxidase activity and edema, all reversed by dexamethasone in G-3. CONCLUSION: Trauma by severance of thigh muscles in healthy rats is a simple and efficient model to induce distant lung lesions.OBJETIVO: Desenvolver um modelo facilmente reprodutível de lesão pulmonar aguda decorrente de trauma muscular experimental em ratos sadios. MÉTODOS: Dezoito ratos Wistar adultos foram randomizados em 3 grupos (n=6: G-1-controle, G-2 - trauma+salina e G-3 - trauma+dexametasona. Grupos G-1 e G-2 foram tratados com salina 2,0 ml ip, G-3 ratos foram tratados com dexametasona (DE (2 mg/kg peso corporal ip. Salina e DE foram aplicadas 2h antes e 12h depois do trauma. Trauma foi induzido em ratos G-2 e G-3 anestesiados (tribromoetanol 97% de 100 ml/kg, i.p. por secção da musculatura anterior da coxa logo acima da articulação do joelho, preservando os grandes vasos e nervos. Amostras de tecido (pulmão foram coletadas para avaliação da mieloperoxidase (MPO, e exames histopatológicos. RESULTADOS: Vinte e quatro horas após a indução da lesão muscular houve um aumento significativo na infiltração de neutr

Scintigraphic diagnosis of experimentally induced pericarditis in dogs using 99sup(m)Tc-labelled pyrophosphate

International Nuclear Information System (INIS)

Duska, F.; Novak, J.; Vizda, J.; Kubizek, J.; Simon, J.; Veverkova, O.; Karlova Universita, Hradec Kralove

1981-01-01

In the present paper the possibilities of scintigraphic diagnosis of experimental pericarditis are discussed. Pericarditis was induced by either talc or formaldehyde intrapericardially. In all animals the administration of talc as well as formaldehyde produced inflammatory changes which were more serious after formaldehyde. The scan of the talc pericarditis was carried out on the 7th day after operation and of the formaldehyde pericarditis on the 3rd, 7th and 14th day. No positive scintigraphic finding was made in any of the experimental animals, apart from a massive incorporation in the operation scars. The counting of radioactive impulses after the exstirpation of the tissue samples confirmed the scintigraphic findings. Statistical evaluation did not reveal any essential difference between the accumulation of the radiopharmaceutical into the pericarditis as well as into the pericardial bag in comparison with the control animals. Although our model does not exactly reflect the situation of patients suffering from pericarditis it may be assumed that pyrophosphate scintigraphy is not suitable for the diagnosis of acute pericarditis in clinical practice. (orig.) [de

Experimental Study on the Effect of Calcitonin in Osteoporosis Induced by the Immobilization and Long-Term Glucocorticoid

International Nuclear Information System (INIS)

Park, Dong Jin; Lee, Sang Rae

1989-01-01

It is well known that the glucocorticoid induces osteoporosis by suppression of the osteoblast, but its effect on the osteoclast has some controversy whether it activates or suppresses the osteoclast. If the calcitonin, which is known to suppress the osteoclast, prevents the osteoporosis by glucocorticoid, then the suppression of the osteoclast by the glucocorticoid is not so significant. And if the calcitonin increases the osteoblastic activity, Tc-99m MDP uptake will be increased in spite of the glucocorticoid effect on the osteoblast. The immobilization operation was performed to the right leg of male Wistar rats weighing about 200 gm each. For 16 weeks after operation, rats were injected glucocorticoid alone or glucocorticoid and calcitonin. The bone density was measured by means of photodensitometry under reference aluminum step wedge and Tc-99m MDP uptake was available to the index of the osteoblastic activity. 1. The bone density of femoral head was markedly reduced than that of femoral shaft following ratio of cancellous and cortical components in both site. 2. glucocorticoid caused decrease in bone density of spine and femur, and there is significantly increase of it when medication of glucocorticoid and calcitonin injection simultaneously than that of glucocorticoid. 3. Tc-99m MDP uptake was revealed significant reduction in medication of glucocorticoid but increase in glucocorticoid and calcitonin injection simultaneously in later experimental period. 4. There was a slight reduction in plasma osteocalcin in medication of glucocorticoid through experimental periods and an increase in its value in case of giving glucocorticoid and calcitonin simultaneously in later experimental period. From these results, we suggest that osteoporosis by immobilization is more pronounced by glucocorticoid hormone and osteoporosis induced by immobilization and glucocorticoid use is prevented by calcitonin administration with increasing osteoblastic activity.

Successful treatment of radiation-induced fibrosis using Cu/Zn-SOD and Mn-SOD: an experimental study.

Science.gov (United States)

Lefaix, J L; Delanian, S; Leplat, J J; Tricaud, Y; Martin, M; Nimrod, A; Baillet, F; Daburon, F

1996-05-01

To establish how far liposomal copper/zinc superoxide dismutase (Cu/Zn-SOD) and manganese superoxide dismutase (Mn-SOD), respectively, reduce radiation-induced fibrosis (RIF), using a well-characterized pig model of RIF permitting the design of a controlled laboratory experiment. In this model of acute localized gamma irradiation simulating accidental overexposure in humans, three groups of five large white pigs were irradiated using a collimated 192Ir source to deliver a single dose of 160 Gy onto the skin surface (100%) of the outer side of the thigh. A well-defined block of subcutaneous fibrosis involving skin and skeletal muscle developed 6 months after irradiation. One experimental group of five pigs was then injected i.m. with 10 mg/10 kg b.wt. of Cu/Zn-SOD, twice a week for 3 weeks, and another experimental group of five was injected with 10 mg/10 kg b.wt. of Mn-SOD, three times a week for 3 weeks. Five irradiated control pigs were injected with physiological serum. Animals were assessed for changes in the density of the palpated fibrotic block and in the dimensions of the projected cutaneous surface. Block depth was determined by ultrasound. Physical and sonographic findings were confirmed by autopsy 12-14 weeks after completing SOD injections. The density, length, width, and depth of the fibrotic block, and the areas and volume of its projected cutaneous surface were compared before treatment, 1, 3, and 6 weeks thereafter, and at autopsy, 12-14 weeks after treatment ended. The experimental animals exhibited no change in behavior and no abnormal clinical or anatomic signs. Whether they were given Cu/Zn- or Mn-SOD, significant and roughly equivalent softening and shrinking of the fibrotic block were noted in all treated animals between the first week after treatment ended and autopsy, when mean regression was 45% for length and width, 30% for depth, and 70% for area and volume. Histologic examination showed completely normal muscle and subcutaneous tissue

Vibration-induced particle formation during yogurt fermentation - Industrial vibration measurements and development of an experimental setup.

Science.gov (United States)

Körzendörfer, Adrian; Temme, Philipp; Nöbel, Stefan; Schlücker, Eberhard; Hinrichs, Jörg

2016-07-01

The aim of the study was to investigate the effects of vibrations during yogurt fermentation. Machinery such as pumps and switching valves generate vibrations that may disturb the gelation by inducing large particles. Oscillation measurements on an industrial yogurt production line showed that oscillations are transferred from pumps right up to the fermentation tanks. An experimental setup (20L) was developed to study the effect of vibrations systematically. The fermenters were decoupled with air springs to enable reference fermentations under idle conditions. A vibration exciter was used to stimulate the fermenters. Frequency sweeps (25-1005Hz, periodic time 10s) for 20min from pH5.4 induced large particles. The number of visible particles was significantly increased from 35±4 (reference) to 89±9 particles per 100g yogurt. Rheological parameters of the stirred yogurt samples were not influenced by vibrations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Experimental study on flow-induced acoustic resonance in square closed side branch

International Nuclear Information System (INIS)

Zhang Hui; Gu Hanyang; Liu Xiaojing; Zhang Kai; Xie Yongcheng; Zu Hongbiao

2014-01-01

Flow-induced acoustic resonance is a phenomenon caused by the interaction of flow and acoustic fields in special structure. Acoustic resonance characteristic experiments were carried out on square closed side branch. The influences of the velocity in main pipe and the length of the side branch on acoustic resonance were studied. The range of occurrence and characteristics of pressure pulsation were analyzed. Three lengths of side branches (L/d=5.6 and 7) were experimentally studied and the Reynolds number in the experiment was 2.74 X 10 4 -2.429 X 10 5 while the Mach number was 0.025-0.218. The results show that the resonance frequency shows a lock-in phenomenon with the increase of velocity. As the length of the side branch increasing, the amplitude of the acoustic pressure and the resonance frequency decrease. In the considered structure, the acoustic resonance occurs when Strouhal number is 0.3-0.6 and 0.7-1.0. (authors)

Experimental characterization of fire-induced response of rigid polyurethane foam

Energy Technology Data Exchange (ETDEWEB)

Chu, T.Y.; Gill, W.; Moore, J.W.; Hobbs, M.L.; Gritzo, L.A.; Moya, J.L.

1995-12-31

Reported is the result of an experimental investigation of fire-induced response of a 96 kg/m{sup 3} closed cell rigid polyurethane foam. The specimen is 0.37 m in diameter, and 152 mm thick, placed in a cylindrical test vessel. The fire condition is simulated by heating the bottom of the test vessel to 1283 K using a radiant heat source. Real-time x-ray shows that the degradation process involves the progression of a charring front into the virgin material. The charred region has a regular and graded structure consisting of a packed bubble outer layer and successive layers of thin shells. The layer-to-layer permeability appears to be poor. There are indications that gas vents laterally. The shell-like structure might be the result of lateral venting. Although the foam degradation process is quite complicated, the in-depth temperature responses in the uncharted foam appear to be consistent with steady state ablation. The measured temperature responses are well represented by the exponential distribution for steady state ablation. An estimate of the thermal diffusivity of the foam is obtained from the ablation model. The experiment is part of a more comprehensive program to develop material response models of foams and encapsulants.

Role of the Use of Omental Flap in Prognosis of Cases with Induced Acute Pancreatitis in Experimental Dogs

OpenAIRE

Mohamed Hassan; Nader Shaaban; Ashraf M Abu-Seida; Mostafa Khodeir; Reem Jan; Hisham Elsharkawy; Engie Hefnawy

2016-01-01

Aim Acute pancreatitis frequently involves peripancreatic tissues and remote organ systems resulting in severe complications and high risk of mortality. Therefore, the present study was carried out to assess the effect of omental flap as a new treatment of acute pancreatitis. Methods Ten mongrel dogs with experimentally induced acute pancreatitis were randomly divided into two equal groups; treated and control groups. The pancreas was wrapped with omental flap in the treated group and the pan...

Experimental Induction of Genome Chaos.

Science.gov (United States)

Ye, Christine J; Liu, Guo; Heng, Henry H

2018-01-01

Genome chaos, or karyotype chaos, represents a powerful survival strategy for somatic cells under high levels of stress/selection. Since the genome context, not the gene content, encodes the genomic blueprint of the cell, stress-induced rapid and massive reorganization of genome topology functions as a very important mechanism for genome (karyotype) evolution. In recent years, the phenomenon of genome chaos has been confirmed by various sequencing efforts, and many different terms have been coined to describe different subtypes of the chaotic genome including "chromothripsis," "chromoplexy," and "structural mutations." To advance this exciting field, we need an effective experimental system to induce and characterize the karyotype reorganization process. In this chapter, an experimental protocol to induce chaotic genomes is described, following a brief discussion of the mechanism and implication of genome chaos in cancer evolution.

Concentrations of cysteinyl leukotrienes in urine and bronchoalveolar lavage fluid of cats with experimentally induced asthma.

Science.gov (United States)

Norris, Carol R; Decile, Kendra C; Berghaus, Londa J; Berghaus, Roy D; Walby, William F; Schelegle, Edward S; Hyde, Dallas M; Gershwin, Laurel J

2003-11-01

To evaluate changes in cysteinyl leukotriene (LT) concentrations in urine and bronchoalveolar lavage fluid (BALF) in cats with experimentally induced asthma. 19 cats with experimentally induced asthma and 5 control cats. Cats were sensitized to Bermuda grass or house dust mite allergen, and phenotypic features of asthma were confirmed with intradermal skin testing, evaluation of BALF eosinophil percentages, and pulmonary function testing. A competitive ELISA kit for LTC4, LTD4, and LTE4 was used for quantitative analysis of LTs. Urinary creatinine concentrations and BALF total protein (TP) concentrations were measured, and urinary LT-to-creatinine ratios and BALF LT-to-TP ratios were calculated. Mean urinary LT-to-creatinine ratios did not differ significantly between control cats and allergen-sensitized cats before or after sensitization and challenge exposure with saline (0.9% NaCl) solution or allergen, respectively. In BALF the mean LT-to-TP ratio of control cats did not differ significantly before or after sensitization and challenge exposure with saline. Asthmatic cats had BALF LT-to-TP ratios that were significantly lower than control cats at all time points, whereas ratios for asthmatic cats did not differ significantly among the various time points. Although LTs were readily detectable in urine, no significant increases in urinary LT concentrations were detected after challenge in allergen-sensitized cats. Spot testing of urinary LT concentrations appears to have no clinical benefit for use in monitoring the inflammatory asthmatic state in cats. The possibility that cysteinyl LTs bind effectively to their target receptors in BALF and, thus, decrease free LT concentrations deserves further study.

Experimental study of flow induced vibration of the planar fuel assembly

International Nuclear Information System (INIS)

Wang Jinhua; Bo Hanliang; Jiang Shengyao; Jia Haijun; Zheng Wenxiang; Min Gang; Qu Xinxing

2005-01-01

The paper studied the flow-induced vibration of the planar fuel assembly under scour of coolant through experiments, the study includes: the characteristics of the inherent vibration, the response to the flow-induced vibration in rating condition and the confirmation of the critical flow velocity's scope of the flow flexible instability. The velocity distributions in different flow channels formed by fuel plates in the assembly were measured, and the velocity distribution in the same flow channel was also measured. The experimental conclusions includes: the inherent vibration frequency of the planar fuel assembly is different for a little in each direction. The damp ratio corresponding to the assembly each rank's inherent frequency is small, and the damp ratio decreased with the increase of the corresponding inherent frequency. The velocity in different flow channels decreased from outside to inside, and the velocity in the middle channel was the least; the velocity in the same channel decreased from inside to outside, and the velocity in the middle position was the most. The vibration swing of the fuel assembly was small at rating condition, and the vibration swing of the fuel plates was larger than side plates. The vibration of the fuel assembly increased with the increase of the velocity, the vibration of the middle fuel plate were larger than the border fuel plate, and the vibration of the border fuel plate was larger than the side plate. The large scale vibration of the flow flexible instability didn't occur in the velocity scope of 0-18.8 m/s in the experiment, so the critical flow velocity of the flow flexible instability was not in the flow velocity scope of the experiment. (authors)

Proton-induced accelerated decay of the fungicide, vinclozolin, on TiO2 surface under solar irradiation: Experimental and DFT study.

Science.gov (United States)

Osipov, Ivan; Gorbachev, Mikhail Y; Gorinchoy, Natalia N

2018-04-03

The photochemical degradation of vinclozolin by addition of titanium dioxide on silica support has been examined both experimental and quantum-chemically. Solar irradiation of vinclozolin on silica with and without addition of titanium dioxide for 6 h resulted in 21% and 97.8% vinclozolin residues, respectively. In both these cases, phototransformation leads to the formation of (3,5-dichlorophenyl isocyanate) and (3,5-dichloroaniline). The presence of the intermediary product resulted from opening of the 2,4-oxazolidine-dione ring is also confirmed by GS-MS and LC-MS chromatography. The proton-induced mechanism of vinclozolin decay at the above experimental conditions is clarified on the base of DFT calculations.

Bone Marrow-Derived Mononuclear Cell Therapy in Papain-Induced Experimental Pulmonary Emphysema

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Mariana N. Machado

2018-02-01

Full Text Available Murine papain-induced emphysema is a model that reproduces many of the features found in patients. Bone marrow-derived mononuclear cells (BMMC have already been used to repair the alveolar epithelium in respiratory diseases, but not in the papain model. Thus, we hypothesized that BMMC could prevent the pathophysiological processes in papain-induced experimental emphysema. Female BALB/c mice received intratracheal instillation of 50 μL of saline (S groups or papain (P groups, 10 IU/50 μl of saline on days 1 and 7 of the experimental protocol. On the 14th day, 2 × 106 BMMC of male BALB/c mice (SC21 and PC21 or saline (SS21 and PS21 were injected by the jugular vein. Analyses were done on days 14 (S14 and P14 and 21 (SS21, PS21, SC21, and PC21 of the protocol. qPCR evaluated the presence of the Y chromosome in the lungs of BMMC recipient animals. Functional residual capacity (FRC, alveolar diameter, cellularity, elastic fiber content, concentrations of TNF-α, IL-1β, IL-6, MIP-2, KC, IFN-γ, apoptosis, mRNA expression of the dual oxidase (DUOX1 and DUOX2, production of H2O2 and DUOX activity were evaluated in lung tissue. We did not detect the Y chromosome in recipients' lungs. FRC, alveolar diameter, polymorphonuclear cells (PMN and levels of KC, MIP-2, and IFN-γ increased in P14 and PS21 groups; the changes in the latter were reverted by BMMC. TNF-α, IL-1β e IL-6 were similar in all groups. The amount of elastic fibers was smaller in P14 and PS21 than in other groups, and BMMC did not increase it in PC21 mice. PS21 animals showed increased DUOX activity and mRNA expression for DUOX1 and 2. Cell therapy reverted the activity of DUOX and mRNA expression of DUOX1. BMMC reduced mRNA expression of DUOX2. Apoptosis index was elevated in PS21 mice, which was reduced by cell therapy in PC21. Static compliance, viscoelastic component of elastance and pressure to overcome viscoelasticity were increased in P14 and PS21 groups. These changes and the

Experimental cross sections for light-charged particle production induced by neutrons with energies between 25 and 65 MeV incident on aluminum

International Nuclear Information System (INIS)

Benck, S.; Slypen, I.; Meulders, J.P.; Corcalciuc, V.

2001-01-01

Experimental double-differential cross sections (d 2 σ/dΩdE) for fast neutron-induced proton, deuteron, triton, and alpha-particle production on aluminum are reported, at several incident neutron energies between 25 and 65 MeV, for outgoing particle energies above the experimental energy thresholds. Angular distributions were measured at laboratory angles between 20 deg. and 160 deg. . Reliable extrapolated spectra are derived for very forward (2.5 deg. and 10 deg. ) and very backward angles (170 deg. and 177.5 deg. ). Based on these experimental data, energy-differential (dσ/dE), angle-differential (dσ/dΩ), and total production cross sections (σ T ) are reported for each outgoing particle

Protective effects of total glucosides of paeony and the underlying mechanisms in carbon tetrachloride-induced experimental liver injury

Science.gov (United States)

Qin, Ying; Tian, Ya-ping

2011-01-01

Introduction We explored the protective effects of total glucosides of paeony (TGP) and the underlying mechanisms in carbon tetrachloride (CCl4)-induced experimental liver injury in mice. Material and methods Chronic liver damage was induced by intraperitoneal injection of CCl4 (0.5 µl/g) three times per week for 8 weeks. Mice also received 25, 50 or 100 mg/kg TGP. Liver sections were stained with haematoxylin/eosin. Serum amino transferases, lipid peroxidation and tumour necrosis factor-α (TNF-α) levels were determined using commercial assays. Quantitative real-time polymerase chain reaction was used to determine the changes in hepatic TNF-α, COX-2, iNOS and HO-1 expression. Protein levels of nitric oxide synthase, cyclooxygenase-2, haem oxygenase-1 and cytochrome P450 2E1 were determined by western blotting. Results Histological results showed that TGP improved the CCl4-induced changes in liver structure and alleviated lobular necrosis. The increases in serum protein and hepatic mRNA expression of TNF-α induced by CCl4 treatment were suppressed by TGP. Total glucosides of paeony also attenuated the increase the expression in iNOS and CYP2E1 but augmented the increase in HO-1.The mRNA and protein expression levels of inducible HO-1 increased significantly after CCl4 treatment. Conclusions Total glucosides of paeony protects hepatocytes from oxidative damage induced by CCl4. Total glucosides of paeony may achieve these effects by enhancing HO-1 expression and inhibiting the expression of proinflammatory mediators. PMID:22291795

Kaempferol-human serum albumin interaction: Characterization of the induced chirality upon binding by experimental circular dichroism and TDDFT calculations

Science.gov (United States)

Matei, Iulia; Ionescu, Sorana; Hillebrand, Mihaela

2012-10-01

The experimental induced circular dichroism (ICD) and absorption spectra of the achiral flavonoid kaempferol upon binding to human serum albumin (HSA) were correlated to electronic CD and UV-vis spectra theoretically predicted by time-dependent density functional theory (TDDFT). The neutral and four anionic species of kaempferol in various conformations were considered in the calculations. The appearance of the experimental ICD signal was rationalized in terms of kaempferol binding to HSA in a distorted, chiral, rigid conformation. The comparison between the experimental and simulated spectra allowed for the identification of the kaempferol species that binds to HSA, namely the anion generated by deprotonation of the hydroxyl group in position 7. This approach constitutes a convenient method for evidencing the binding species and for determining its conformation in the binding pocket of the protein. Its main advantage over the UV-vis absorption method lays in the fact that only the bound ligand species gives an ICD signal.

Recruitment of 99m-technetium- or 111-indium-labelled polymorphonuclear leucocytes in experimentally induced pyogranulomas in lambs

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Guilloteau, L.; Pepin, M.; Pardon, P.; Le Pape, A. (Institut National de la Recherche Agronomique, Nouzilly (France))

1990-10-01

The recruitment of polymorphonuclear leucocytes (PMNs) during the development of experimental pyogranulomas induced by Corynebacterium pseudotuberculosis was followed in nine male lambs by scintigraphic examination. Autologous blood PMNs were labelled with 99m-technetium or 111-indium and were re-injected intravenously into infected lambs. The functional properties of the labelled cells were monitored (1) in vitro by measuring their phagocytic and bactericidal activity against C. pseudotuberculosis and their chemotaxis under agarose, and (2) in vivo by following scintigraphically their capacity to accumulate in an inflammatory focus induced by intradermal injection of latex beads coated with Salmonella abortus equi lipopolysaccharide. Following inoculation of corynebacteria into the right ear of lambs, radioactive foci were observed to be localized in the right ear and in the draining lymph nodes during the 4 days following inoculation. Histopathological examination performed 32 h after inoculation confirmed the intense accumulation of PMNs at these sites. With the exception of one animal, which presented visible foci in the neck 14 days postinoculation, no radioactive foci were observed during the later phases of experimental infection, despite the presence of multiple pyogranulomas which were confirmed by bacteriological examination after necropsy of the lambs. Histopathological examination of these lesions revealed layers of fibroblasts, lymphocytes, and macrophages surrounding a necrotic centre. The results of these studies suggest that the contribution of PMNs during the chronic phase of inflammation is considerably reduced in comparison with the acute inflammatory phase of the infectious process.

Recruitment of 99m-technetium- or 111-indium-labelled polymorphonuclear leucocytes in experimentally induced pyogranulomas in lambs

International Nuclear Information System (INIS)

Guilloteau, L.; Pepin, M.; Pardon, P.; Le Pape, A.

1990-01-01

The recruitment of polymorphonuclear leucocytes (PMNs) during the development of experimental pyogranulomas induced by Corynebacterium pseudotuberculosis was followed in nine male lambs by scintigraphic examination. Autologous blood PMNs were labelled with 99m-technetium or 111-indium and were re-injected intravenously into infected lambs. The functional properties of the labelled cells were monitored (1) in vitro by measuring their phagocytic and bactericidal activity against C. pseudotuberculosis and their chemotaxis under agarose, and (2) in vivo by following scintigraphically their capacity to accumulate in an inflammatory focus induced by intradermal injection of latex beads coated with Salmonella abortus equi lipopolysaccharide. Following inoculation of corynebacteria into the right ear of lambs, radioactive foci were observed to be localized in the right ear and in the draining lymph nodes during the 4 days following inoculation. Histopathological examination performed 32 h after inoculation confirmed the intense accumulation of PMNs at these sites. With the exception of one animal, which presented visible foci in the neck 14 days postinoculation, no radioactive foci were observed during the later phases of experimental infection, despite the presence of multiple pyogranulomas which were confirmed by bacteriological examination after necropsy of the lambs. Histopathological examination of these lesions revealed layers of fibroblasts, lymphocytes, and macrophages surrounding a necrotic centre. The results of these studies suggest that the contribution of PMNs during the chronic phase of inflammation is considerably reduced in comparison with the acute inflammatory phase of the infectious process

Integral analyses of fission product retention at mitigated thermally-induced SGTR using ARTIST experimental data

International Nuclear Information System (INIS)

Rýdl, Adolf; Lind, Terttaliisa; Birchley, Jonathan

2016-01-01

Highlights: • Source term analyses in a PWR of mitigated thermally-induced SGTR scenario performed. • Experimental ARTIST program results on aerosol scrubbing efficiency used in analyses. • Results demonstrate enhanced aerosol retention in a flooded steam generator. • High aerosol retention cannot be predicted by current theoretical scrubbing models. - Abstract: Integral source-term analyses are performed using MELCOR for a PWR Station Blackout (SBO) sequence leading to induced steam generator tube rupture (SGTR). In the absence of any mitigation measures, such a sequence can result in a containment bypass where the radioactive materials can be released directly to the environment. In some SGTR scenarios flooding of the faulted SG secondary side with water can mitigate the accident escalation and also the release of aerosol-borne and volatile radioactive materials. Data on the efficiency of aerosol scrubbing in an SG tube bundle were obtained in the international ARTIST project. In this paper ARTIST data are used directly with parametric MELCOR analyses of a mitigated SGTR sequence to provide more realistic estimates of the releases to environment in such a type of scenario or similar. Comparison is made with predictions using the default scrubbing model in MELCOR, as a representative of the aerosol scrubbing models in current integral codes. Specifically, simulations are performed for an unmitigated sequence and 2 cases where the SG secondary was refilled at different times after the tube rupture. The results, reflecting the experimental observations from ARTIST, demonstrate enhanced aerosol retention in the highly turbulent two-phase flow conditions caused by the complex geometry of the SG secondary side. This effect is not captured by any of the models currently available. The underlying physics remains only partly understood, indicating need for further studies to support a more mechanistic treatment of the retention process.

Ablation of rat TRPV1-expressing Adelta/C-fibers with resiniferatoxin: analysis of withdrawal behaviors, recovery of function and molecular correlates

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Haspel Gal

2010-12-01

Full Text Available Abstract Background Ablation of TRPV1-expressing nociceptive fibers with the potent capsaicin analog resiniferatoxin (RTX results in long lasting pain relief. RTX is particularly adaptable to focal application, and the induced chemical axonopathy leads to analgesia with a duration that is influenced by dose, route of administration, and the rate of fiber regeneration. TRPV1 is expressed in a subpopulation of unmyelinated C- and lightly myelinated Adelta fibers that detect changes in skin temperature at low and high rates of noxious heating, respectively. Here we investigate fiber-type specific behaviors, their time course of recovery and molecular correlates of axon damage and nociception using infrared laser stimuli following an RTX-induced peripheral axonopathy. Results RTX was injected into rat hind paws (mid-plantar to produce thermal hypoalgesia. An infrared diode laser was used to stimulate Adelta fibers in the paw with a small-diameter (1.6 mm, high-energy, 100 msec pulse, or C-fibers with a wide-diameter (5 mm, long-duration, low-energy pulse. We monitored behavioral responses to indicate loss and regeneration of fibers. At the site of injection, responses to C-fiber stimuli were significantly attenuated for two weeks after 5 or 50 ng RTX. Responses to Adelta stimuli were significantly attenuated for two weeks at the highest intensity stimulus, and for 5 weeks to a less intense Adelta stimulus. Stimulation on the toe, a site distal to the injection, showed significant attenuation of Adelta responses for 7- 8 weeks after 5 ng, or 9-10 weeks after 50 ng RTX. In contrast, responses to C-fiber stimuli exhibited basically normal responses at 5 weeks after RTX. During the period of fiber loss and recovery, molecular markers for nerve regeneration (ATF3 and galanin are upregulated in the dorsal root ganglia (DRG when behavior is maximally attenuated, but markers of nociceptive activity (c-Fos in spinal cord and MCP-1 in DRG, although induced

Interleukin-12 promotes activation of effector cells that induce a severe destructive granulomatous form of murine experimental autoimmune thyroiditis.

OpenAIRE

Braley-Mullen, H.; Sharp, G. C.; Tang, H.; Chen, K.; Kyriakos, M.; Bickel, J. T.

1998-01-01

Granulomatous inflammatory lesions are a major histopathological feature of a wide spectrum of human infectious and autoimmune diseases. Experimental autoimmune thyroiditis (EAT) with granulomatous histopathological features can be induced by mouse thyroglobulin (MTg)-sensitized spleen cells activated in vitro with MTg and anti-interleukin-2 receptor (anti-IL-2R), anti-IL-2, or anti-interferon-gamma (anti-IFN-gamma) monoclonal antibody (MAb). These studies suggested that IFN-gamma-producing T...

An experimental approach to improve the Monte Carlo modelling of offline PET/CT-imaging of positron emitters induced by scanned proton beams

International Nuclear Information System (INIS)

Bauer, J; Unholtz, D; Kurz, C; Parodi, K

2013-01-01

We report on the experimental campaign carried out at the Heidelberg Ion-Beam Therapy Center (HIT) to optimize the Monte Carlo (MC) modelling of proton-induced positron-emitter production. The presented experimental strategy constitutes a pragmatic inverse approach to overcome the known uncertainties in the modelling of positron-emitter production due to the lack of reliable cross-section data for the relevant therapeutic energy range. This work is motivated by the clinical implementation of offline PET/CT-based treatment verification at our facility. Here, the irradiation induced tissue activation in the patient is monitored shortly after the treatment delivery by means of a commercial PET/CT scanner and compared to a MC simulated activity expectation, derived under the assumption of a correct treatment delivery. At HIT, the MC particle transport and interaction code FLUKA is used for the simulation of the expected positron-emitter yield. For this particular application, the code is coupled to externally provided cross-section data of several proton-induced reactions. Studying experimentally the positron-emitting radionuclide yield in homogeneous phantoms provides access to the fundamental production channels. Therefore, five different materials have been irradiated by monoenergetic proton pencil beams at various energies and the induced β + activity subsequently acquired with a commercial full-ring PET/CT scanner. With the analysis of dynamically reconstructed PET images, we are able to determine separately the spatial distribution of different radionuclide concentrations at the starting time of the PET scan. The laterally integrated radionuclide yields in depth are used to tune the input cross-section data such that the impact of both the physical production and the imaging process on the various positron-emitter yields is reproduced. The resulting cross-section data sets allow to model the absolute level of measured β + activity induced in the investigated

An experimental approach to improve the Monte Carlo modelling of offline PET/CT-imaging of positron emitters induced by scanned proton beams

Science.gov (United States)

Bauer, J.; Unholtz, D.; Kurz, C.; Parodi, K.

2013-08-01

We report on the experimental campaign carried out at the Heidelberg Ion-Beam Therapy Center (HIT) to optimize the Monte Carlo (MC) modelling of proton-induced positron-emitter production. The presented experimental strategy constitutes a pragmatic inverse approach to overcome the known uncertainties in the modelling of positron-emitter production due to the lack of reliable cross-section data for the relevant therapeutic energy range. This work is motivated by the clinical implementation of offline PET/CT-based treatment verification at our facility. Here, the irradiation induced tissue activation in the patient is monitored shortly after the treatment delivery by means of a commercial PET/CT scanner and compared to a MC simulated activity expectation, derived under the assumption of a correct treatment delivery. At HIT, the MC particle transport and interaction code FLUKA is used for the simulation of the expected positron-emitter yield. For this particular application, the code is coupled to externally provided cross-section data of several proton-induced reactions. Studying experimentally the positron-emitting radionuclide yield in homogeneous phantoms provides access to the fundamental production channels. Therefore, five different materials have been irradiated by monoenergetic proton pencil beams at various energies and the induced β+ activity subsequently acquired with a commercial full-ring PET/CT scanner. With the analysis of dynamically reconstructed PET images, we are able to determine separately the spatial distribution of different radionuclide concentrations at the starting time of the PET scan. The laterally integrated radionuclide yields in depth are used to tune the input cross-section data such that the impact of both the physical production and the imaging process on the various positron-emitter yields is reproduced. The resulting cross-section data sets allow to model the absolute level of measured β+ activity induced in the investigated

Development and characterization of an experimental model of diet-induced metabolic syndrome in rabbit.

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Oscar Julián Arias-Mutis

Full Text Available Metabolic syndrome (MetS has become one of the main concerns for public health because of its link to cardiovascular disease. Murine models have been used to study the effect of MetS on the cardiovascular system, but they have limitations for studying cardiac electrophysiology. In contrast, the rabbit cardiac electrophysiology is similar to human, but a detailed characterization of the different components of MetS in this animal is still needed. Our objective was to develop and characterize a diet-induced experimental model of MetS that allows the study of cardiovascular remodeling and arrhythmogenesis. Male NZW rabbits were assigned to control (n = 15 or MetS group (n = 16, fed during 28 weeks with high-fat, high-sucrose diet. We measured weight, morphological characteristics, blood pressure, glycaemia, standard plasma biochemistry and the metabolomic profile at weeks 14 and 28. Liver histological changes were evaluated using hematoxylin-eosin staining. A mixed model ANOVA or unpaired t-test were used for statistical analysis (P<0.05. Weight, abdominal contour, body mass index, systolic, diastolic and mean arterial pressure increased in the MetS group at weeks 14 and 28. Glucose, triglycerides, LDL, GOT-AST, GOT/GPT, bilirubin and bile acid increased, whereas HDL decreased in the MetS group at weeks 14 and 28. We found a 40% increase in hepatocyte area and lipid vacuoles infiltration in the liver from MetS rabbits. Metabolomic analysis revealed differences in metabolites related to fatty acids, energetic metabolism and microbiota, compounds linked with cardiovascular disease. Administration of high-fat and high-sucrose diet during 28 weeks induced obesity, glucose intolerance, hypertension, non-alcoholic hepatic steatosis and metabolic alterations, thus reproducing the main clinical manifestations of the metabolic syndrome in humans. This experimental model should provide a valuable tool for studies into the mechanisms of cardiovascular

Experimental pleurodesis induced by antibiotics (macrolides or quinolones Pleurodese experimental induzida por antibióticos (macrolídeos e quinolonas

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Lisete R. Teixeira

2006-01-01

Full Text Available PURPOSE: Chemical pleurodesis is a therapeutic tool for the treatment of recurrent pleural effusions, mainly those of neoplastic etiology. In the past, tetracycline was the sclerosant agent of choice in clinical practice, but presently, there is no consensus about an ideal agent. The aim of this study was to evaluate the effectiveness of macrolides (azithromycin and clarithromycin or quinolones (levofloxacin and gatifloxacin in inducing experimental pleurodesis in rabbits. METHOD: Forty New Zealand rabbits randomized into groups of 10 received (at a total volume of 2 mL for each animal 1 of the 4 drugs by intrapleural injection. After 28 days, the animals were euthanized and the pleural cavity was evaluated macroscopically and microscopically. RESULTS: The intensity of the macroscopic adhesions was mild in all groups. On microscopic analysis, minimal pleural fibrosis and inflammation were observed in all animals. CONCLUSION: The macrolides (azithromycin or clarithromycin and the quinolones (levofloxacin or gatifloxacin when injected into the normal pleural space of rabbits are not effective in promoting pleurodesis. Additional research is required to identify sclerosing agents capable of inducing pleurodesis.OBJETIVO: A pleurodese química representa uma ferramenta terapêutica utilizada no tratamento dos processos pleurais recidivantes, principalmente nos derrames neoplásicos. A escolha do melhor esclerosante pleural é ainda motivo de controvérsia, não havendo consenso com relação ao agente considerado ideal. O objetivo deste estudo é avaliar a efetividade dos macrolídeos (azitromicina e claritromicina e das quinolonas (levofloxacina e gatifloxacina na indução de pleurodese experimental em coelhos. MÉTODOS: Quarenta animais randomizados em grupos de 10, receberam, em volume total de 2 mL, estas drogas através de injeção intrapleural. RESULTADOS: Após 28 dias, os animais foram sacrificados sendo avaliada a cavidade pleural. A

Expression of ALS/FTD-linked mutant CCNF in zebrafish leads to increased cell death in the spinal cord and an aberrant motor phenotype.

Science.gov (United States)

Hogan, Alison L; Don, Emily K; Rayner, Stephanie L; Lee, Albert; Laird, Angela S; Watchon, Maxinne; Winnick, Claire; Tarr, Ingrid S; Morsch, Marco; Fifita, Jennifer A; Gwee, Serene S L; Formella, Isabel; Hortle, Elinor; Yuan, Kristy C; Molloy, Mark P; Williams, Kelly L; Nicholson, Garth A; Chung, Roger S; Blair, Ian P; Cole, Nicholas J

2017-07-15

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive, fatal neurodegenerative disease characterised by the death of upper and lower motor neurons. Approximately 10% of cases have a known family history of ALS and disease-linked mutations in multiple genes have been identified. ALS-linked mutations in CCNF were recently reported, however the pathogenic mechanisms associated with these mutations are yet to be established. To investigate possible disease mechanisms, we developed in vitro and in vivo models based on an ALS-linked missense mutation in CCNF. Proteomic analysis of the in vitro models identified the disruption of several cellular pathways in the mutant model, including caspase-3 mediated cell death. Transient overexpression of human CCNF in zebrafish embryos supported this finding, with fish expressing the mutant protein found to have increased levels of cleaved (activated) caspase-3 and increased cell death in the spinal cord. The mutant CCNF fish also developed a motor neuron axonopathy consisting of shortened primary motor axons and increased frequency of aberrant axonal branching. Importantly, we demonstrated a significant correlation between the severity of the CCNF-induced axonopathy and a reduced motor response to a light stimulus (photomotor response). This is the first report of an ALS-linked CCNF mutation in vivo and taken together with the in vitro model identifies the disruption of cell death pathways as a significant consequence of this mutation. Additionally, this study presents a valuable new tool for use in ongoing studies investigating the pathobiology of ALS-linked CCNF mutations. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Experimental study of acoustic damping induced by gas-liquid scheme injectors in a combustion chamber

International Nuclear Information System (INIS)

Kim, Hak Soon; Sohn, Chae Hoon

2007-01-01

In a liquid rocket engine, acoustic damping induced by gas-liquid scheme injectors is studied experimentally for combustion stability by adopting linear acoustic test. In the previous work, it has been found that gas-liquid scheme injector can play a significant role in acoustic damping or absorption when it is tuned finely. Based on this finding, acoustic-damping characteristics of multi-injectors are intensively investigated. From the experimental data, it is found that acoustic oscillations are almost damped out by multi-injectors when they have the tuning length proposed in the previous study. The length corresponds to a half wavelength of the first longitudinal overtone mode traveling inside the injector with the acoustic frequency intended for damping in the chamber. But, new injector-coupled acoustic modes show up in the chamber with the injectors of the tuning length although the target mode is nearly damped out. And, appreciable frequency shift is always observed except for the case of the worst tuned injector. Accordingly, it is proposed that the tuning length is adjusted to have the shorter length than a half wavelength when these phenomena are considered

The bystander effect in experimental systems and compatibility with radon-induced lung cancer in humans

International Nuclear Information System (INIS)

Little, M.P.; Wakeford, R.

2002-01-01

Bystander effects following exposure to α-particles have been observed in C3H 10T 1/2 cells and in other experimental systems, and imply that linearly extrapolating low-dose risks from high-dose data might materially underestimate risk. The ratio of lung cancer risk among persons exposed to low and high doses of radon daughters is 2.4-4.0, with an upper 95% confidence limit (CL) of about 14. Assuming that the bystander effect observed in the C3H 10T 1/2 data applies to human lung cells in vivo, the epidemiological data imply that the number of neighbouring cells that can contribute to the bystander effect is between 0 and 1, with an upper 95% CL of about 7. As a consequence, the bystander effect observed in the C3H 10T 1/2 system probably does not play a large part in the process of radon-induced lung carcinogenesis in humans. Other experimental data relating to the bystander effect after α-particle exposure are surveyed; some of these data are more compatible with the epidemiological data. (author)

Retrograde axonal transport of 125I-nerve growth factor in rat ileal mesenteric nerves. Effect of streptozocin diabetes

International Nuclear Information System (INIS)

Schmidt, R.E.; Plurad, S.B.; Saffitz, J.E.; Grabau, G.G.; Yip, H.K.

1985-01-01

The retrograde axonal transport of intravenously (i.v.) administered 125 I-nerve growth factor ( 125 I-NGF) was examined in mesenteric nerves innervating the small bowel of rats with streptozocin (STZ) diabetes using methods described in detail in the companion article. The accumulation of 125 I-NGF distal to a ligature on the ileal mesenteric nerves of diabetic animals was 30-40% less than in control animals. The inhibition of accumulation of 125 I-NGF in diabetic animals was greater at a ligature tied 2 h after i.v. administration than at a ligature tied after 14 h, which suggests that the diabetic animals may have a lag in initiation of NGF transport in the terminal axon or retardation of transport at some site along the axon. The 125 I-NGF transport defect was observed as early as 3 days after the induction of diabetes, a time before the development of structural axonal lesions, and did not worsen at later times when dystrophic axonopathy is present. Both the ileal mesenteric nerves, which eventually develop dystrophic axonopathy in experimental diabetes, and the jejunal mesenteric nerves, which never develop comparable structural alterations, showed similar 125 I-NGF transport deficits, suggesting that the existence of the transport abnormality does not predict the eventual development of dystrophic axonal lesions. Autoradiographic localization of 125 I-NGF in the ileal mesenteric nerves of animals that had been diabetic for 11-13 mo demonstrated decreased amounts of 125 I-NGF in transit in unligated paravascular nerve fascicles. There was, however, no evidence for focal retardation of transported 125 I-NGF at the sites of dystrophic axonal lesions

Toxic neuropathies: Mechanistic insights based on a chemical perspective.

Science.gov (United States)

LoPachin, Richard M; Gavin, Terrence

2015-06-02

2,5-Hexanedione (HD) and acrylamide (ACR) are considered to be prototypical among chemical toxicants that cause central-peripheral axonopathies characterized by distal axon swelling and degeneration. Because the demise of distal regions was assumed to be causally related to the onset of neurotoxicity, substantial effort was devoted to deciphering the respective mechanisms. Continued research, however, revealed that expression of the presumed hallmark morphological features was dependent upon the daily rate of toxicant exposure. Indeed, many studies reported that the corresponding axonopathic changes were late developing effects that occurred independent of behavioral and/or functional neurotoxicity. This suggested that the toxic axonopathy classification might be based on epiphenomena related to dose-rate. Therefore, the goal of this mini-review is to discuss how quantitative morphometric analyses and the establishment of dose-dependent relationships helped distinguish primary, mechanistically relevant toxicant effects from non-specific consequences. Perhaps more importantly, we will discuss how knowledge of neurotoxicant chemical nature can guide molecular-level research toward a better, more rational understanding of mechanism. Our discussion will focus on HD, the neurotoxic γ-diketone metabolite of the industrial solvents n-hexane and methyl-n-butyl ketone. Early investigations suggested that HD caused giant neurofilamentous axonal swellings and eventual degeneration in CNS and PNS. However, as our review will point out, this interpretation underwent several iterations as the understanding of γ-diketone chemistry improved and more quantitative experimental approaches were implemented. The chemical concepts and design strategies discussed in this mini-review are broadly applicable to the mechanistic studies of other chemicals (e.g., n-propyl bromine, methyl methacrylate) that cause toxic neuropathies. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Experimentally-induced maternal hypothyroidism alters crucial enzyme activities in the frontal cortex and hippocampus of the offspring rat.

Science.gov (United States)

Koromilas, Christos; Tsakiris, Stylianos; Kalafatakis, Konstantinos; Zarros, Apostolos; Stolakis, Vasileios; Kimpizi, Despoina; Bimpis, Alexios; Tsagianni, Anastasia; Liapi, Charis

2015-02-01

Thyroid hormone insufficiency during neurodevelopment can result into significant structural and functional changes within the developing central nervous system (CNS), and is associated with the establishment of serious cognitive impairment and neuropsychiatric symptomatology. The aim of the present study was to shed more light on the effects of gestational and/or lactational maternal exposure to propylthiouracil (PTU)-induced hypothyroidism as a multilevel experimental approach to the study of hypothyroidism-induced changes on crucial brain enzyme activities of 21-day-old Wistar rat offspring in a brain region-specific manner. This experimental approach has been recently developed and characterized by the authors based on neurochemical analyses performed on newborn and 21-day-old rat offspring whole brain homogenates; as a continuum to this effort, the current study focused on two CNS regions of major significance for cognitive development: the frontal cortex and the hippocampus. Maternal exposure to PTU in the drinking water during gestation and/or lactation resulted into changes in the activities of acetylcholinesterase and two important adenosinetriphosphatases (Na(+),K(+)- and Mg(2+)-ATPase), that seemed to take place in a CNS-region-specific manner and that were dependent upon the PTU-exposure timeframe followed. As these findings are analyzed and compared to the available literature, they: (i) highlight the variability involved in the changes of the aforementioned enzymatic parameters in the studied CNS regions (attributed to both the different neuroanatomical composition and the thyroid-hormone-dependent neurodevelopmental growth/differentiation patterns of the latter), (ii) reveal important information with regards to the neurochemical mechanisms that could be involved in the way clinical hypothyroidism could affect optimal neurodevelopment and, ultimately, cognitive function, as well as (iii) underline the need for the adoption of more consistent

Radiation damage to the normal monkey brain. Experimental study induced by interstitial irradiation

International Nuclear Information System (INIS)

Mishima, Nobuya; Tamiya, Takashi; Matsumoto, Kengo; Furuta, Tomohisa; Ohmoto, Takashi

2003-01-01

Radiation damage to normal brain tissue induced by interstitial irradiation with iridium-192 seeds was sequentially evaluated by computed tomography (CT), magnetic resonance imaging (MRI), and histological examination. This study was carried out in 14 mature Japanese monkeys. The experimental area received more than 200-260 Gy of irradiation developed coagulative necrosis. Infiltration of macrophages to the periphery of the necrotic area was seen. In addition, neovascularization, hyalinization of vascular walls, and gliosis were found in the periphery of the area invaded by the macrophages. All sites at which the vascular walls were found to have acute stage fibrinoid necrosis eventually developed coagulative necrosis. The focus of necrosis was detected by MRI starting 1 week after the end of radiation treatment, and the size of the necrotic area did not change for 6 months. The peripheral areas showed clear ring enhancement with contrast material. Edema surrounding the lesions was the most significant 1 week after radiation and was reduced to a minimum level 1 month later. However, the edema then expanded once again and was sustained for as long as 6 months. CT did not provide as clear of a presentation as MRI, but it did reveal similar findings for the most part, and depicted calcification in the necrotic area. This experimental model is considered useful for conducting basic research on brachytherapy, as well as for achieving a better understanding of delayed radiation necrosis. (author)

Effect of Camel Milk on Oxidative Stresses in Experimentally Induced Diabetic Rabbits

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Esraa Tantawy

2010-06-01

Full Text Available Camel milk has an importance in the treatment of diabetes. It has been shown that the patients who drink camel milk daily, their need to insulin decrease. Therefore, this study aimed to investigate the effect of camel milk in comparison with insulin treatment in experimentally-induced diabetes. This study was carried out on forty male New Zealand rabbits, divided into four groups with ten rabbits in each. The first group G1 was considered as control non-diabetic group and received only normal saline solution. The other animals were injected intravenously with alloxan for induction of diabetes mellitus and then divided into three groups' ten rabbits each as the follows: G2 considered as control diabetic and left untreated, G3 was considered as diabetic and treated with insulin, and G4 was considered as diabetic and received camel milk. At the end of the experiment (4 weeks, blood (whole blood & serum and tissue samples (liver, kidney and pancreas were collected from all the animals for analysis of: enzymatic SOD and catalase, non-enzymatic GSH antioxidant enzyme activities. Serum malondialdeyde, glucose, insulin and lipid profile also were analyzed. The results showed that the camel milk was effective in the treatment of diabetes in comparison to insulin treatment alone. In addition to its hypoglycemic effect, camel milk improved the diabetes-induced oxidative stress. The histopathological evaluations demonstrated that there was a regeneration in β cells and the islets of Langerhans among the pancreatic acini in rabbits receiving camel milk. Our findings suggested that the camel milk administration in case of insulin dependant diabetes mellitus might be recommended as an oral anti-diabetic remedy.

Experimental Evidence of Momentum Transport Induced by an Up-Down Asymmetric Magnetic Equilibrium in Toroidal Plasmas

International Nuclear Information System (INIS)

Camenen, Y.; Peeters, A. G.; Casson, F. J.; Hornsby, W. A.; Snodin, A. P.; Szepesi, G.; Bortolon, A.; Duval, B. P.; Federspiel, L.; Karpushov, A. N.; Piras, F.; Sauter, O.

2010-01-01

The first experimental evidence of parallel momentum transport generated by the up-down asymmetry of a toroidal plasma is reported. The experiments, conducted in the Tokamak a Configuration Variable, were motivated by the recent theoretical discovery of ion-scale turbulent momentum transport induced by an up-down asymmetry in the magnetic equilibrium. The toroidal rotation gradient is observed to depend on the asymmetry in the outer part of the plasma leading to a variation of the central rotation by a factor of 1.5-2. The direction of the effect and its magnitude are in agreement with theoretical predictions for the eight possible combinations of plasma asymmetry, current, and magnetic field.

Pairing experimentation and computational modelling to understand the role of tissue inducer cells in the development of lymphoid organs

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Kieran eAlden

2012-07-01

Full Text Available The use of genetic tools, imaging technologies and ex vivo culture systems has provided significant insights into the role of tissue inducer cells and associated signalling pathways in the formation and function of lymphoid organs. Despite advances in experimental technologies, the molecular and cellular process orchestrating the formation of a complex 3-dimensional tissue is difficult to dissect using current approaches. Therefore, a robust set of simulation tools have been developed to model the processes involved in lymphoid tissue development. Specifically the role of different tissue inducer cell populations in the dynamic formation of Peyer's Patches has been examined. Utilising approaches from critical systems engineering an unbiased model of lymphoid tissue inducer cell function has been developed, that permits the development of emerging behaviours that are statistically not different from that observed in vivo. These results provide the confidence to utilise statistical methods to explore how the simulator predicts cellular behaviour and outcomes under different physiological conditions. Such methods, known as sensitivity analysis techniques, can provide insight into when a component part of the system (such as a particular cell type, adhesion molecule, or chemokine begins to have an influence on observed behaviour, and quantifies the effect a component part has on the end result: the formation of lymphoid tissue. Through use of such a principled approach in the design, calibration, and analysis of a computer simulation, a robust in silico tool can be developed which can both further the understanding of a biological system being explored, and act as a tool for the generation of hypotheses which can be tested utilising experimental approaches.

Radiographic evaluation of experimentally induced nephrosis in goats

Energy Technology Data Exchange (ETDEWEB)

Kumar, R.; Pandey, N. N.; Singh, G. R.; Setia, H. C. [Indian Veterinary Research Institute, Izatnagar (India)

1995-06-15

Intravenous pyelography (IVP) with pneumoperitoneum (PP) was undertaken in normal and induced nephrotic goats. In normal goats, the technique provided visualization of both the kidneys, renal pelvis, ureter and urinary bladder at 10 min post-administration of sodium iothalamate (70%). In mercuric chloride- and oxytetracycline-induced nephrosis in goats, the urinary tract could not be visualized even 60 min post-administration of dye indicating sever failure of renal excretory function. However, in gentamicin-abused goats, renal excretory function was not significantly altered owing to a very mild renal damage. It was concluded that IVP with PP could be a dependable diagnostic test for varied degree of renal insufficiency in ruminants.

Radiographic evaluation of experimentally induced nephrosis in goats

International Nuclear Information System (INIS)

Kumar, R.; Pandey, N.N.; Singh, G.R.; Setia, H.C.

1995-01-01

Intravenous pyelography (IVP) with pneumoperitoneum (PP) was undertaken in normal and induced nephrotic goats. In normal goats, the technique provided visualization of both the kidneys, renal pelvis, ureter and urinary bladder at 10 min post-administration of sodium iothalamate (70%). In mercuric chloride- and oxytetracycline-induced nephrosis in goats, the urinary tract could not be visualized even 60 min post-administration of dye indicating sever failure of renal excretory function. However, in gentamicin-abused goats, renal excretory function was not significantly altered owing to a very mild renal damage. It was concluded that IVP with PP could be a dependable diagnostic test for varied degree of renal insufficiency in ruminants

Numerical and experimental investigation of laser induced plasma spectrum of aluminum in the presence of a noble gas

International Nuclear Information System (INIS)

Rezaei, Fatemeh; Tavassoli, Seyed Hassan

2012-01-01

Laser-induced plasma emission of an aluminum target in helium gas at 1 atm pressure is numerically and experimentally investigated. A laser pulse at wavelength of 266 nm and pulse duration of 10 ns has been considered. Laser ablation is calculated by a one dimensional model based on thermal evaporation mechanism. Spatial and temporal parameters of plasma expansion are determined by using hydrodynamic equations. Three kinds of plasma emission, including Bremsstrahlung, recombination and spectral emissions are considered for modeling the spectrum. Strong lines of aluminum and helium in wavelength interval of 200 to 450 nm are selected. Aluminum spectrum in UV range is depicted and compared with other spectral ranges. Temporal and spatial evolution of plasma emission up to 200 ns after the laser irradiation is studied. The effect of laser energy on the plasma spectrum is studied. An experimental set-up is arranged to compare numerical calculations with experimental results. Experimental and numerical results illustrate that helium line widths and peak intensities become narrower and weaker with time, respectively. Spatial distribution of spectrum shows that for closer distance to the sample surface, an intense continuous emission is observed, while at the farther distance, continuous emission decreases and spectral lines become sharper. A good coincidence is observed between experimental and numerical results. - Highlights: ► Aluminum plasma emission in helium is numerically and experimentally studied. ► Spectral, Bremsstrahlung and recombination emissions in spectrum are calculated. ► All strong lines of aluminum and helium are chosen for spectrum simulation. ► Line widths and peak intensities at later times become narrower and weaker. ► At specific optimum position, the maximum of signal peaks is acquired.

Assessment of contrast-enhanced ultrasonography of the hepatic vein for detection of hemodynamic changes associated with experimentally induced portal hypertension in dogs.

Science.gov (United States)

Morishita, Keitaro; Hiramoto, Akira; Michishita, Asuka; Takagi, Satoshi; Hoshino, Yuki; Itami, Takaharu; Lim, Sue Yee; Osuga, Tatsuyuki; Nakamura, Sayuri; Ochiai, Kenji; Nakamura, Kensuke; Ohta, Hiroshi; Yamasaki, Masahiro; Takiguchi, Mitsuyoshi

2017-04-01

OBJECTIVE To assess the use of contrast-enhanced ultrasonography (CEUS) of the hepatic vein for the detection of hemodynamic changes associated with experimentally induced portal hypertension in dogs. ANIMALS 6 healthy Beagles. PROCEDURES A prospective study was conducted. A catheter was surgically placed in the portal vein of each dog. Hypertension was induced by intraportal injection of microspheres (10 to 15 mg/kg) at 5-day intervals via the catheter. Microsphere injections were continued until multiple acquired portosystemic shunts were created. Portal vein pressure (PVP) was measured through the catheter. Contrast-enhanced ultrasonography was performed before and after establishment of hypertension. Time-intensity curves were generated from the region of interest in the hepatic vein. Perfusion variables measured for statistical analysis were hepatic vein arrival time, time to peak, time to peak phase (TTPP), and washout ratio. The correlation between CEUS variables and PVP was assessed by use of simple regression analysis. RESULTS Time to peak and TTPP were significantly less after induction of portal hypertension. Simple regression analysis revealed a significant negative correlation between TTPP and PVP. CONCLUSIONS AND CLINICAL RELEVANCE CEUS was useful for detecting hemodynamic changes associated with experimentally induced portal hypertension in dogs, which was characterized by a rapid increase in the intensity of the hepatic vein. Furthermore, TTPP, a time-dependent variable, provided useful complementary information for predicting portal hypertension. IMPACT FOR HUMAN MEDICINE Because the method described here induced presinusoidal portal hypertension, these results can be applied to idiopathic portal hypertension in humans.

Experimental Study on Piezoelectric Energy Harvesting from Vortex-Induced Vibrations and Wake-Induced Vibrations

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Min Zhang

2016-01-01

Full Text Available A rigid circular cylinder with two piezoelectric beams attached on has been tested through vortex-induced vibrations (VIV and wake-induced vibrations (WIV by installing a big cylinder fixed upstream, in order to study the influence of the different flow-induced vibrations (FIV types. The VIV test shows that the output voltage increases with the increases of load resistance; an optimal load resistance exists for the maximum output power. The WIV test shows that the vibration of the small cylinder is controlled by the vortex frequency of the large one. There is an optimal gap of the cylinders that can obtain the maximum output voltage and power. For a same energy harvesting device, WIV has higher power generation capacity; then the piezoelectric output characteristics can be effectively improved.

Experimental headache in humans

DEFF Research Database (Denmark)

Iversen, Helle Klingenberg

1995-01-01

The need for valid human experimental models of headache is obvious. Several compounds have been proposed as headache-inducing agents, but only the nitroglycerin (NTG) model has been validated. In healthy subjects, intravenous infusions of the nitric oxide (NO) donor NTG induce a dose......-dependent headache and dilatation of the temporal, radial and middle cerebral artery. NTG-induced headache, although less intense, resembles migraine in pain characteristics, but the accompanying symptoms are rarely present. Cephalic large arteries are dilated during migraine headache as well as during NTG headache....... N-acetylcysteine enhances the formation of NO and potentiates NTG-induced headache, whereas mepyramine, a H1-antagonist capable of blocking histamine-induced headache, has no effect. Thus, the headache is dependent on NO or other steps in the NO cascade. The model is useful for pharmacological...

Experimental study and nuclear model calculations of {sup 3}He-induced nuclear reactions on zinc

Energy Technology Data Exchange (ETDEWEB)

Al-Abyad, M.; Mohamed, Gehan Y. [Nuclear Research Centre, Atomic Energy Authority, Physics Department (Cyclotron Facility), Cairo (Egypt); Ditroi, F.; Takacs, S.; Tarkanyi, F. [Hungarian Academy of Sciences (ATOMKI), Institute for Nuclear Research, Debrecen (Hungary)

2017-05-15

Excitation functions of {sup 3}He-induced nuclear reactions on natural zinc were measured using the standard stacked-foil technique and high-resolution gamma-ray spectrometry. From their threshold energies up to 27 MeV, the cross-sections for {sup nat}Zn ({sup 3}He,xn) {sup 69}Ge, {sup nat}Zn({sup 3}He,xnp) {sup 66,67,68}Ga, and {sup nat}Zn({sup 3}He,x){sup 62,65}Zn reactions were measured. The nuclear model codes TALYS-1.6, EMPIRE-3.2 and ALICE-IPPE were used to describe the formation of these products. The present data were compared with the theoretical results and with the available experimental data. Integral yields for some important radioisotopes were determined. (orig.)

Antiepileptic effect of fisetin in iron-induced experimental model of traumatic epilepsy in rats in the light of electrophysiological, biochemical, and behavioral observations.

Science.gov (United States)

Das, Jharana; Singh, Rameshwar; Sharma, Deepak

2017-05-01

Traumatic epilepsy is defined by episodes of recurring seizures secondary to severe brain injury. Though drugs are found effective to control seizures, their long-term use have been observed to increase reactive oxygen species in animals. Flavonoid fisetin, a natural bioactive phytonutrient reported to exert anticonvulsive effect in experimental seizure models. But, trauma-induced seizures could not be prevented by anticonvulsants was reported in some clinical studies. To study the effect of fisetin on epileptiform electrographic activity in iron-induced traumatic epilepsy and also the probable reason behind the effect in rats. Fisetin pretreatment (20 mg/kg body wt., p.o.) of rats for 12 weeks were chosen followed by injecting iron (5 µl, 100 mM) stereotaxically to generate iron-induced epilepsy. Experimental design include electrophysiological study (electroencephalograph in correlation with multiple unit activity (MUA) in the cortex and CA1 subfield of the hippocampus; spectral analysis of seizure and seizure-associated behavioral study (Morris water maze for spatial learning, open-field test for anxiety) and biochemical study (lipid peroxidation, Na + ,K + -ATPase activity) in both the cortex and the hippocampus. Fisetin pretreatment was found to prevent the development of iron-induced electrical seizure and decrease the corresponding MUA in the cortex (*P˂0.05) as well as in the hippocampus (***P˂0.001). Fisetin pretreatment decreased the lipid peroxides (*P˂0.05) and retained the Na + ,K + -ATPase activity (*P˂0.05) which was found altered in the epileptic animals and also found to attenuate the seizure-associated cognitive dysfunctions. This study demonstrated the antiepileptic action of fisetin in iron-induced model of epileptic rats by inhibiting oxidative stress.

Deeply inelastic transfer reactions induced by heavy ions in rare earth targets. II. Interpretation of experimental data

International Nuclear Information System (INIS)

Rivet, M.F.; Bimbot, R.; Ngo, C.

1979-01-01

The experimental angular distributions and cross sections for a series of deeply inelastic transfer reactions induced by various projectiles in rare earth targets have been interpreted using a model which includes a dynamical coupling between relative motion and mass asymmetry and treats statistical fluctuations. As the transfer reactions considered correspond to an increase of the potential energy of the composite system their observation is mainly due to fluctuations. The calculation reproduces correctly the angular distributions, but the cross sections are underestimated. Several effects are discussed which may increase these cross sections and are neglected in the calculation

Experimental radiation carcinogenesis is studies at NIRS

International Nuclear Information System (INIS)

Sado, Toshihiko

1992-01-01

Experimental radiation carcinogenesis studies conducted during the past decade at NIRS are briefly reviewed. They include the following: 1) Age dependency of susceptibility to radiation carcinogenesis. 2) Radiation-induced myeloid leukemia. 3) Mechanism of fractionated X-irradiation (FX) induced thymic lymphomas. 4) Significance of radiation-induced immunosuppression in radiation carcinogenesis in vivo. 5) Other ongoing studies. (author)

Drug induced acute kidney injury: an experimental animal study

International Nuclear Information System (INIS)

Khan, M.W.A.; Khan, B.T.; Qazi, R.A.; Ashraf, M.; Waqar, M.

2017-01-01

Objective: To assess the extent of drug induced nephrotoxicity in laboratory animals for determining the role and extent of iatrogenic kidney damage in patients exposed to nephrotoxic drugs in various clinical setups. Study Design: Randomized control trail. Place and Duration of study: Pharmacology department and animal house of Army Medical College from Jan 2011 to Aug 2011. Material and Methods: Thirty six mixed breed rabbits were used in this study. Animals were randomly divided into six groups consisting of six rabbits in each. Groups were named A, B, C, D, E and F. Group A was control group. Group B was given 0.9% normal saline. Group C rabbits were given acute nephrotoxic single dose of amphotericin B deoxycholate. Group D received 0.9% normal saline 10ml/kg followed by amphotericin B infusion. Group E was injected acute nephrotoxic regimen of cyclosporine and amphotericin B infusion. Group F received saline loading along with acute nephrotoxic regimen of cyclosporine and amphotericin B infusion. Results: Biochemical and histopathological analysis showed significant kidney injury in rabbits exposed to acute nephrotoxic doses of amphotericin B and cyclosporine. Toxicity was additive when the two drugs were administered simultaneously. Group of rabbits with saline loading had significantly lesser kidney damage. Conclusion: Iatrogenic acute kidney damage is a major cause of morbidity in experimental animals exposed to such nephrotoxic drugs like amphotericin B and cyclosporine, used either alone or in combination. Clinical studies are recommended to assess the extent of iatrogenic renal damage in patients and its economic burden. Efficient and cost effective protective measure may be adopted in clinical setups against such adverse effects. (author)

Aterosclerose experimental em coelhos Experimental atherosclerosis in rabbits

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Waleska C. Dornas

2010-08-01

Full Text Available Numerosas pesquisas têm sido realizadas utilizando modelos experimentais para estudar o desenvolvimento da aterosclerose com dieta induzindo hiperlipidemia. Devido ao fato de que coelhos são muito sensíveis a dietas ricas em colesterol e acumulam grandes quantidades no plasma, a utilização destes animais como modelo experimental para avaliar o desenvolvimento de aterosclerose é de grande relevância, trazendo informação sobre fatores que contribuem para progressão e regressão aplicadas a situações humanas. Sendo assim, nessa revisão a função aterogênica do colesterol é mostrada em trabalhos que incluem o coelho como modelo experimental, uma vez que este animal tornou-se o mais popular modelo experimental de aterosclerose.Many researches have been conducted in experimental models in order to study the development of atherosclerosis from hyperlipidemia-inducing diets. Since rabbits are very sensitive to cholesterol-rich diets and accumulate large amounts of cholesterol in their plasma, their use as experimental models to evaluate the development of atherosclerosis is highly relevant and brings information on factors that contribute to the progression and regression of this condition that can be applied to humans. As such, this review includes studies on the atherogenic function of cholesterol based on rabbits as the experimental model, since they have become the most largely used experimental model of atherosclerosis.

Comparison of the effects of candesartan cilexetil and enalapril maleate on right ventricular myocardial remodeling in dogs with experimentally induced pulmonary stenosis.

Science.gov (United States)

Yamane, Tsuyoshi; Fujii, Yoko; Orito, Kensuke; Osamura, Kaori; Kanai, Takao; Wakao, Yoshito

2008-12-01

To compare the effects of candesartan cilexetil and enalapril maleate on right ventricular myocardial remodeling in dogs with experimentally induced pulmonary stenosis. 24 Beagles. 18 dogs underwent pulmonary arterial banding (PAB) to induce right ventricular pressure overload, and 6 healthy dogs underwent sham operations (thoracotomy only [sham-operated group]). Dogs that underwent PAB were allocated to receive 1 of 3 treatments (6 dogs/group): candesartan (1 mg/kg, PO, q 24 h [PABC group]), enalapril (0.5 mg/kg, PO, q 24 h [PABE group]), or no treatment (PABNT group). Administration of treatments was commenced the day prior to surgery; control dogs received no cardiac medications. Sixty days after surgery, right ventricular wall thickness was assessed echocardiographically and plasma renin activity, angiotensin-converting enzyme activity, and angiotensin I and II concentrations were assessed; all dogs were euthanatized, and collagenous fiber area, cardiomyocyte diameter, and tissue angiotensin-converting enzyme and chymase-like activities in the right ventricle were evaluated. After 60 days of treatment, right ventricular wall thickness, cardiomyocyte diameter, and collagenous fiber area in the PABNT and PABE groups were significantly increased, compared with values in the PABC and sham-operated groups. Chymase-like activity was markedly greater in the PABE group than in other groups. Results indicated that treatment with candesartan but not enalapril effectively prevented myocardial remodeling in dogs with experimentally induced subacute right ventricular pressure overload.

Experimental and analytical studies on pedestrian induced footbridge vibrations

DEFF Research Database (Denmark)

Gudmundsson, Gudmundur Valur; Ingólfsson, Einar Thór; Einarsson, Baldvin

2007-01-01

characteristics and to measure the response of the bridges to human induced excitation such as walking, running and jumping. Two of the bridges were a part of a design competition related to the realignment of an existing highway in the city centre of Reykjavik in 2005. The bridges have similar cross sections...... modes corresponding to the measured values. The models were subsequently used to calculate the predicted acceleration according to the preliminary version of the Eurocode (ENV 1992-2: Concrete bridges) using time-history analysis with a moving load as representative for a single pedestrian. The load...... models describing human-induced vibrations on structures in current literature and standards are explained, both for a single person walking or running and crowd loading. The measured vertical acceleration induced by single pedestrians was compared against the predictions and it was found that all...

Excess amounts of 3-iodo-l-tyrosine induce Parkinson-like features in experimental approaches of Parkinsonism.

Science.gov (United States)

Fernández-Espejo, Emilio; Bis-Humbert, Cristian

2018-06-06

3-iodo-l-tyrosine might play a role in Parkinson's disease since this molecule is able, at high concentration, to inhibit tyrosine-hydroxylase activity, the rate-limiting enzyme in dopamine biosynthesis. The possible Parkinson-like effects of 3-iodo-l-tyrosine were tested on three experimental approaches in mice: cultured substantia nigra neurons, the enteric nervous system of the jejunum after intra-peritoneal infusions, and the nigrostriatal system following unilateral intrabrain injections. 3-iodo-l-tyrosine, a physiological molecule, was used at concentrations higher than its serum levels in humans. Parkinson-like signs were evaluated through abnormal aggregation of α-synuclein and tyrosine-hydroxylase, loss of tyrosine-hydroxylase-expressing and striatum-projecting neurons and fibers, reduced tyrosine-hydroxylase density, and Parkinson-like motor and non-motor deficits. The retrograde tracer FluoroGold was used in the brain model. The findings revealed that excess amounts of 3-iodo-l-tyrosine induce Parkinson-like effects in the three experimental approaches. Thus, culture neurons of substantia nigra show, after 3-iodo-l-tyrosine exposure, intracytoplasmic inclusions that express α-synuclein and tyrosine-hydroxylase. Intra-peritoneal infusions of 3-iodo-l-tyrosine cause, in the long-term, α-synuclein aggregation, thicker α-synuclein-positive fibers, and loss of tyrosine-hydroxylase-positive cells and fibers in intramural plexuses and ganglia of the jejunum. Infusion of 3-iodo-l-tyrosine into the left dorsal striata of mice damages the nigrostriatal system, as revealed through lower striatal tyrosine-hydroxylase density, reduced number of tyrosine-hydroxylase-expressing and striatum-projecting neurons in the left substantia nigra, as well as the emergence of Parkinson-like behavioral deficits such as akinesia, bradykinesia, motor disbalance, and locomotion directional bias. In conclusion, excess amounts of 3-iodo-l-tyrosine induce Parkinson-like features in

Transgenic expression of soluble human CD5 enhances experimentally-induced autoimmune and anti-tumoral immune responses.

Directory of Open Access Journals (Sweden)

Rafael Fenutría

Full Text Available CD5 is a lymphoid-specific transmembrane glycoprotein constitutively expressed on thymocytes and mature T and B1a lymphocytes. Current data support the view that CD5 is a negative regulator of antigen-specific receptor-mediated signaling in these cells, and that this would likely be achieved through interaction with CD5 ligand/s (CD5L of still undefined nature expressed on immune or accessory cells. To determine the functional consequence of loss of CD5/CD5L interaction in vivo, a new transgenic mouse line was generated (shCD5EμTg, expressing a circulating soluble form of human CD5 (shCD5 as a decoy to impair membrane-bound CD5 function. These shCD5EμTg mice showed an enhanced response to autologous antigens, as deduced from the presentation of more severe forms of experimentally inducible autoimmune disease (collagen-induced arthritis, CIA; and experimental autoimmune encephalitis, EAE, as well as an increased anti-tumoral response in non-orthotopic cancer models (B16 melanoma. This enhancement of the immune response was in agreement with the finding of significantly reduced proportions of spleen and lymph node Treg cells (CD4+CD25+FoxP3+, and of peritoneal IL-10-producing and CD5+ B cells, as well as an increased proportion of spleen NKT cells in shCD5EμTg mice. Similar changes in lymphocyte subpopulations were observed in wild-type mice following repeated administration of exogenous recombinant shCD5 protein. These data reveal the relevant role played by CD5/CD5L interactions on the homeostasis of some functionally relevant lymphocyte subpopulations and the modulation of immune responses to autologous antigens.

Determination of ultra-short laser induced damage threshold of KH2PO4 crystal: Numerical calculation and experimental verification

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Jian Cheng

2016-03-01

Full Text Available Rapid growth and ultra-precision machining of large-size KDP (KH2PO4 crystals with high laser damage resistance are tough challenges in the development of large laser systems. It is of high interest and practical significance to have theoretical models for scientists and manufacturers to determine the laser-induced damage threshold (LIDT of actually prepared KDP optics. Here, we numerically and experimentally investigate the laser-induced damage on KDP crystals in ultra-short pulse laser regime. On basis of the rate equation for free electron generation, a model dedicated to predicting the LIDT is developed by considering the synergistic effect of photoionization, impact ionization and decay of electrons. Laser damage tests are performed to measure the single-pulse LIDT with several testing protocols. The testing results combined with previously reported experimental data agree well with those calculated by the model. By taking the light intensification into consideration, the model is successfully applied to quantitatively evaluate the effect of surface flaws inevitably introduced in the preparation processes on the laser damage resistance of KDP crystals. This work can not only contribute to further understanding of the laser damage mechanisms of optical materials, but also provide available models for evaluating the laser damage resistance of exquisitely prepared optical components used in high power laser systems.

Experimental study of boundary layer transition on an airfoil induced by periodically passing wake (II)

Energy Technology Data Exchange (ETDEWEB)

Park, T.C. [Seoul National University Graduate School, Seoul (Korea); Jeon, W.P.; Kang, S.H. [Seoul National University, Seoul (Korea)

2001-06-01

This paper describes the phenomena of wake-induced transition of the boundary layers on a NACA0012 airfoil using measured phase-averaged data. Especially, the phase-averaged wall shear stresses are reasonably evaluated using the principle of Computational Preston Tube Method. Due to the passing wake, the turbulent patch is generated in the laminar boundary layer on the airfoil and the boundary layer becomes temporarily transitional. The patches propagate downstream with less speed than free-stream velocity and merge with each other at further downstream station, and the boundary layer becomes more transitional. The generation of turbulent patch at the leading edge of the airfoil mainly depends on velocity defects and turbulent intensity profiles of passing wakes. However, the growth and merging of turbulent patches depend on local streamwise pressure gradients as well as characteristics of turbulent patches. In this transition process, the present experimental data show very similar features to the previous numerical and experimental studies. It is confirmed that the two phase-averaged mean velocity dips appear in the outer region of transitional boundary layer for each passing cycle. Relatively high values of the phase-averaged turbulent fluctuations in the outer region indicate the possibility that breakdown occurs in the outer layer not near the wall. (author). 21 refs., 12 figs.

Numerical and experimental investigation of laser induced plasma spectrum of aluminum in the presence of a noble gas

Energy Technology Data Exchange (ETDEWEB)

Rezaei, Fatemeh, E-mail: f_rezaei@sbu.ac.ir; Tavassoli, Seyed Hassan

2012-12-01

Laser-induced plasma emission of an aluminum target in helium gas at 1 atm pressure is numerically and experimentally investigated. A laser pulse at wavelength of 266 nm and pulse duration of 10 ns has been considered. Laser ablation is calculated by a one dimensional model based on thermal evaporation mechanism. Spatial and temporal parameters of plasma expansion are determined by using hydrodynamic equations. Three kinds of plasma emission, including Bremsstrahlung, recombination and spectral emissions are considered for modeling the spectrum. Strong lines of aluminum and helium in wavelength interval of 200 to 450 nm are selected. Aluminum spectrum in UV range is depicted and compared with other spectral ranges. Temporal and spatial evolution of plasma emission up to 200 ns after the laser irradiation is studied. The effect of laser energy on the plasma spectrum is studied. An experimental set-up is arranged to compare numerical calculations with experimental results. Experimental and numerical results illustrate that helium line widths and peak intensities become narrower and weaker with time, respectively. Spatial distribution of spectrum shows that for closer distance to the sample surface, an intense continuous emission is observed, while at the farther distance, continuous emission decreases and spectral lines become sharper. A good coincidence is observed between experimental and numerical results. - Highlights: Black-Right-Pointing-Pointer Aluminum plasma emission in helium is numerically and experimentally studied. Black-Right-Pointing-Pointer Spectral, Bremsstrahlung and recombination emissions in spectrum are calculated. Black-Right-Pointing-Pointer All strong lines of aluminum and helium are chosen for spectrum simulation. Black-Right-Pointing-Pointer Line widths and peak intensities at later times become narrower and weaker. Black-Right-Pointing-Pointer At specific optimum position, the maximum of signal peaks is acquired.

Hemorrhoids: an experimental model in monkeys

Directory of Open Access Journals (Sweden)

Plapler Hélio

2006-01-01

Full Text Available PURPOSE: Hemorrhoids are a matter of concern due to a painful outcome. We describe a simple, easy and reliable experimental model to produce hemorrhoids in monkeys. METHODS: 14 monkeys (Cebus apella were used. After general anesthesia, hemorrhoids were induced by ligation of the inferior hemorrhoidal vein, which is very alike to humans. The vein was located through a perianal incision, dissected and ligated with a 3-0 vicryl. The skin was sutured with a 4-0 catgut thread. Animals were kept in appropriate cages and evaluated daily. RESULTS: Nine days later there were hemorrhoidal piles in the anus in fifty percent (50% of the animals. Outcome was unremarkable. There was no bleeding and all animals showed no signs of pain or suffering. CONCLUSION: This is an affordable and reliable experimental model to induce hemorrhoids for experimental studies.

A new calculation method adapted to the experimental conditions for determining samples γ-activities induced by 14 MeV neutrons

International Nuclear Information System (INIS)

Rzama, A.; Erramli, H.; Misdaq, M.A.

1994-01-01

Induced gamma-activities of different disk shaped irradiated samples and standards with 14 MeV neutrons have been determined by using a Monte Carlo calculation method adapted to the experimental conditions. The self-absorption of the multienergetic emitted gamma rays has been taken into account in the final samples activities. The influence of the different activation parameters has been studied. Na, K, Cl and P contents in biological (red beet) samples have been determined. ((orig.))

Repair of experimental plaque-induced periodontal disease in dogs.

Science.gov (United States)

Shoukry, M; Ben Ali, L; Abdel Naby, M; Soliman, A

2007-09-01

Forty mongrel dogs were used in this study for induction of periodontal disease by placing subgingival silk ligatures affecting maxillary and mandibular premolar teeth during a 12-month period. Experimental premolar teeth received monthly clinical, radiographic, and histometric/pathologic assessments. The results demonstrated significant increases in scores and values of periodontal disease parameters associated with variable degrees of alveolar bone loss. The experimental maxillary premolar teeth exhibited more severe and rapid rates of periodontal disease compared with mandibular premolar teeth. Histometric analysis showed significant reduction in free and attached gingiva of the experimental teeth. Histopathological examination of buccolingual sections from experimental premolar teeth showed the presence of rete pegs within the sulcular epithelium with acanthosis and erosive changes, widening of the periodontal ligament, and alveolar bone resorption. Various methods for periodontal repair were studied in 194 experimental premolar teeth exhibiting different degrees of periodontal disease. The treatment plan comprised non-surgical (teeth scaling, root planing, and oral hygiene) and surgical methods (closed gingival curettage, modified Widman flap, and reconstructive surgery using autogenous bone marrow graft and canine amniotic membrane). The initial non-surgical treatment resulted in a periodontal recovery rate of 37.6% and was found effective for treatment of early periodontal disease based on resolution of gingivitis and reduction of periodontal probing depths. Surgical treatment by closed gingival curettage to eliminate the diseased pocket lining resulted in a recovery rate of 48.8% and proved effective in substantially reducing deep periodontal pockets. Open root planing following flap elevation resulted in a recovery rate of 85.4% and was effective for deep and refractory periodontal pockets. Autogenous bone graft implantation combined with canine amniotic

Microbiologic, Pharmacokinetic, and Clinical Effects of Corneal Collagen Cross-Linking on Experimentally Induced Pseudomonas Keratitis in Rabbits.

Science.gov (United States)

Cosar, C Banu; Kucuk, Mutlu; Celik, Ekrem; Gonen, Tansu; Akyar, Isin; Serteser, Mustafa; Tokat, Fatma; Ince, Umit

2015-10-01

To determine the effects of corneal collagen cross-linking (CXL) on the penetration of topical 0.5% moxifloxacin, on the number of colony-forming units (CFUs) in the cornea, and on the clinical course in a rabbit eye model of experimentally induced Pseudomonas aeruginosa keratitis. In this prospective animal study, experimental Pseudomonas corneal ulcers were induced in 56 corneas of 28 albino New Zealand rabbits. The corneas were randomly divided into the following 4 groups: the control group (14 eyes), the MOX group (moxifloxacin) (14 eyes), the MOX + CXL group (14 eyes), and the CXL group (14 eyes). On day 4 of the experiment, the eyes in the control group were enucleated and CFU counting was performed. On day 10 of the experiment, all eyes were enucleated and CFU counting was performed. In the MOX and MOX + CXL groups, the moxifloxacin level in the cornea, aqueous humor, iris, plasma, and serum was measured by reverse-phase high-performance liquid chromatography. The difference in the corneal CFU count between the MOX group and the MOX + CXL group was not significant (P = 0.317). Clinical improvement was greatest in the MOX + CXL group (P < 0.001). The mean corneal moxifloxacin level was 0.391 ± 0.09 μg·mg in the MOX group versus 0.291 ± 0.09 μg·mg in the MOX + CXL group; as such, CXL did not have a significant effect on antibiotic penetrance (P = 0.386). Clinical improvement was greatest in the MOX + CXL group. The synergistic effect of CXL on corneal ulcer treatment is not through antibiotic penetrance.

Designing experimental setup and procedures for studying alpha-particle-induced adaptive response in zebrafish embryos in vivo

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Choi, V.W.Y.; Lam, R.K.K.; Chong, E.Y.W. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Cheng, S.H. [Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Yu, K.N., E-mail: peter.yu@cityu.edu.h [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong)

2010-03-15

The present work was devoted to designing the experimental setup and the associated procedures for alpha-particle-induced adaptive response in zebrafish embryos in vivo. Thin PADC films with a thickness of 16 mum were fabricated and employed as support substrates for holding dechorionated zebrafish embryos for alpha-particle irradiation from the bottom through the films. Embryos were collected within 15 min when the light photoperiod began, which were then incubated and dechorionated at 4 h post fertilization (hpf). They were then irradiated at 5 hpf by alpha particles using a planar {sup 241}Am source with an activity of 0.1151 muCi for 24 s (priming dose), and subsequently at 10 hpf using the same source for 240 s (challenging dose). The levels of apoptosis in irradiated zebrafish embryos at 24 hpf were quantified through staining with the vital dye acridine orange, followed by counting the stained cells under a florescent microscope. The results revealed the presence of the adaptive response in zebrafish embryos in vivo, and demonstrated the feasibility of the adopted experimental setup and procedures.

Protective effect of gallic acid in experimental model of ketamine-induced psychosis: possible behaviour, biochemical, neurochemical and cellular alterations.

Science.gov (United States)

Yadav, Monu; Jindal, Deepak Kumar; Dhingra, Mamta Sachdeva; Kumar, Anil; Parle, Milind; Dhingra, Sameer

2018-04-01

Gallic acid has been reported to possess a number of psychopharmacological activities. These activities are attributed to the antioxidant potential due to the presence of phenolic moeity. The present study was carried out to investigate the protective effects of gallic acid in an experimental model of ketamine-induced psychosis in mice. Ketamine (50 mg/kg, i.p.) was used to induce stereotyped psychotic behavioural symptoms in mice. Behavioural studies (locomotor activity, stereotype behaviour, immobility duration and memory retention) were carried out to investigate the protective of gallic acid on ketamine-induced psychotic symptoms, followed by biochemical and neurochemical changes and cellular alterations in the brain. Chronic treatment with gallic acid for 15 consecutive days significantly attenuated stereotyped behavioural symptoms in mice. Biochemical estimations revealed that gallic acid reduced the lipid peroxidation and restored the total brain proteins. Furthermore, gallic acid remarkably reduced the dopamine levels, AChE activity and inflammatory surge (serum TNF-α), and increased the levels of GABA and increased glutathione in mice. The study revealed that gallic acid could ameliorate psychotic symptoms and biochemical changes in mice, indicating protective effects in psychosis.

Increased oxidative stress and severe arterial remodeling induced by permanent high-flow challenge in experimental pulmonary hypertension

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Fadel Elie

2011-09-01

Full Text Available Abstract Background Involvement of inflammation in pulmonary hypertension (PH has previously been demonstrated and recently, immune-modulating dendritic cells (DCs infiltrating arterial lesions in patients suffering from idiopathic pulmonary arterial hypertension (IPAH and in experimental monocrotaline-induced PH have been reported. Occurrence of perivascular inflammatory cells could be linked to local increase of oxidative stress (OS, as it has been shown for systemic atherosclerosis. The impact of OS on vascular remodeling in PH is still to be determined. We hypothesized, that augmented blood-flow could increase OS and might thereby contribute to DC/inflammatory cell-recruitment and smooth-muscle-cell-proliferation. Methods We applied a monocrotaline-induced PH-model and combined it with permanent flow-challenge. Thirty Sprague-Dawley rats were assigned to following groups: control, monocrotaline-exposure (MCT, monocrotaline-exposure/pneumonectomy (MCT/PE. Results Hemodynamic exploration demonstrated most severe effects in MCT/PE, corresponding in histology to exuberant medial and adventitial remodeling of pulmonary muscular arteries, and intimal remodeling of smaller arterioles; lung-tissue PCR evidenced increased expression of DCs-specific fascin, CD68, proinflammatory cytokines (IL-6, RANTES, fractalkine in MCT/PE and to a lesser extent in MCT. Major OS enzyme NOX-4 was maximal in MCT/PE. Antioxidative stress enzymes Mn-SOD and glutathion-peroxidase-1 were significantly elevated, while HO-1 showed maximal expression in MCT with significant decrease in MCT/PE. Catalase was decreased in MCT and MCT/PE. Expression of NOX-4, but also of MN-SOD in MCT/PE was mainly attributed to a highly increased number of interstitial and perivascular CXCR4/SDF1 pathway-recruited mast-cells. Stress markers malonedialdehyde and nitrotyrosine were produced in endothelial cells, medial smooth muscle and perivascular leucocytes of hypertensive vasculature

Regulation of adenosine deaminase (ADA) on induced mouse experimental autoimmune uveitis (EAU) ‡

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Liang, Dongchun; Zuo, Aijun; Zhao, Ronglan; Shao, Hui; Kaplan, Henry J.; Sun, Deming

2016-01-01

Adenosine is an important regulator of the immune response and adenosine deaminase (ADA) inhibits this regulatory effect by converting adenosine into functionally inactive molecules. Studies have shown that adenosine receptor (AR) agonists can be either anti- or pro-inflammatory. Clarification of the mechanisms that cause these opposing effects should provide a better guide for therapeutic intervention. In this study, we investigated the effect of ADA on the development of experimental autoimmune uveitis (EAU) induced by immunizing EAU-prone mice with a known uveitogenic peptide, IRBP1–20. Our results showed that the effective time to administer a single dose of ADA to suppress induction of EAU was 8–14 days post-immunization, shortly before EAU expression, but ADA treatment at other time points exacerbated disease. ADA preferentially inhibited Th17 responses and this effect was γδ T cell-dependent. Our results demonstrated that the existing immune status strongly influences the anti- or proinflammatory effects of ADA. Our observations should help improve the design of ADA- and AR-targeted therapies. PMID:26856700

BDNF and VEGF in the pathogenesis of stress-induced affective diseases: an insight from experimental studies.

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Nowacka, Marta; Obuchowicz, Ewa

2013-01-01

Stress is known to play an important role in etiology, development and progression of affective diseases. Especially, chronic stress, by initiating changes in the hypothalamic-pituitary-adrenal axis (HPA), neurotransmission and the immune system, acts as a trigger for affective diseases. It has been reported that the rise in the concentration of pro-inflammatory cytokines and persistent up-regulation of glucocorticoid expression in the brain and periphery increases the excitotoxic effect on CA3 pyramidal neurons in the hippocampus resulting in dendritic atrophy, apoptosis of neurons and possibly inhibition of neurogenesis in adult brain. Stress was observed to disrupt neuroplasticity in the brain, and growing evidence demonstrates its role in the pathomechanism of affective disorders. Experimental studies indicate that a well-known brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) which have recently focused increasing attention of neuroscientists, promote cell survival, positively modulate neuroplasticity and hippocampal neurogenesis. In this paper, we review the alterations in BDNF and VEGF pathways induced by chronic and acute stress, and their relationships with HPA axis activity. Moreover, behavioral effects evoked in rodents by both above-mentioned factors and the effects consequent to their deficit are presented. Biochemical as well as behavioral findings suggest that BDNF and VEGF play an important role as components of cascade of changes in the pathomechanism of stress-induced affective diseases. Further studies on the mechanisms regulating their expression in stress conditions are needed to better understand the significance of trophic hypothesis of stress-induced affective diseases.

Role of TRPV1 and ASIC3 channels in experimental occlusal interference-induced hyperalgesia in rat masseter muscle.

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Xu, X X; Cao, Y; Ding, T T; Fu, K Y; Li, Y; Xie, Q F

2016-04-01

Masticatory muscle pain may occur following immediate occlusal alteration by dental treatment. The underlying mechanisms are poorly understood. Transient receptor potential vanilloid-1 (TRPV1) and acid-sensing ion channel-3 (ASIC3) mediate muscle hyperalgesia under various pathologic conditions. We have developed a rat model of experimental occlusal interference (EOI) that consistently induces mechanical hyperalgesia in jaw muscles. Whether TRPV1 and ASIC3 mediate this EOI-induced hyperalgesia is unknown. Rat model of EOI-induced masseter hyperalgesia was established. Real-time polymerase chain reaction, Western blot and retrograde labelling combined with immunofluorescence were performed to evaluate the modulation of TRPV1 and ASIC3 expression in trigeminal ganglia (TGs) and masseter afferents of rats after EOI. The effects of intramuscular administration of TRPV1 and ASIC3 antagonists on the EOI-induced hyperalgesia in masseter muscle were examined. After EOI, gene expressions and protein levels of TRPV1 and ASIC3 in bilateral TGs were up-regulated. The percentage of ASIC3- (but not TRPV1-) positive neurons in masseter afferents increased after EOI. More small-sized and small to medium-sized masseter afferents expressed TRPV1 and ASIC3 separately following EOI. These changes peaked at day 7 and then returned to original status within 10 days after EOI. Intramuscular administration of the TRPV1 antagonist AMG-9810 partially reversed this mechanical hyperalgesia in masseter muscle. No improvement was exhibited after administration of the ASIC3 antagonist APETx2. Co-injection of AMG-9810 and APETx2 enhanced the effect of AMG-9810 administration alone. Peripheral TRPV1 and ASIC3 contribute to the development of the EOI-induced mechanical hyperalgesia in masseter muscle. © 2015 European Pain Federation - EFIC®

Experimental induced avian E. coli salpingitis

DEFF Research Database (Denmark)

Olsen, Rikke Heidemann; Thøfner, Ida; Pors, Susanne Elisabeth

2016-01-01

Several types of Escherichia coli have been associated with extra-intestinal infections in poultry, however, they may vary significantly in their virulence potential. The aim of the present study was to investigate the virulence of five strains of E. coli obtained from different disease......) had a distinct ability to cause disease. Results of the study shows major differences in virulence of different strains of E. coli in ascending infections; however, there was no indication of tissue-specific adaptation, since strains obtained from lesions unrelated to the reproductive system were...... fully capable of causing experimental infection. In conclusion, the study provides evidence for the clinical outcome of infection with E. coli in poultry is largely influenced by the specific strain as well as individual host factors....

TVP1022 attenuates cardiac remodeling and kidney dysfunction in experimental volume overload-induced congestive heart failure.

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Abassi, Zaid A; Barac, Yaron D; Kostin, Sawa; Roguin, Ariel; Ovcharenko, Elena; Awad, Hoda; Blank, Ayelet; Bar-Am, Orit; Amit, Tamar; Schaper, Jutta; Youdim, Moussa; Binah, Ofer

2011-07-01

Despite the availability of many pharmacological and mechanical therapies, the mortality rate among patients with congestive heart failure (CHF) remains high. We tested the hypothesis that TVP1022 (the S-isomer of rasagiline; Azilect), a neuroprotective and cytoprotective molecule, is also cardioprotective in the settings of experimental CHF in rats. In rats with volume overload-induced CHF, we investigated the therapeutic efficacy of TVP1022 (7.5 mg/kg) on cardiac function, structure, biomarkers, and kidney function. Treatment with TVP1022 for 7 days before CHF induction prevented the increase in left ventricular end-diastolic area and end-systolic area, and the decrease in fractional shortening measured 14 days after CHF induction. Additionally, TVP1022 pretreatment attenuated CHF-induced cardiomyocyte hypertrophy, fibrosis, plasma and ventricular B-type natriuretic peptide levels, and reactive oxygen species expression. Further, in CHF rats, TVP1022 decreased cytochrome c and caspase 3 expression, thereby contributing to the cardioprotective efficacy of the drug. TVP1022 also enhanced the urinary Na(+) excretion and improved the glomerular filtration rate. Similar cardioprotective effects were obtained when TVP1022 was given to rats after CHF induction. TVP1022 attenuated the adverse functional, structural, and molecular alterations in CHF, rendering this drug a promising candidate for improving cardiac and renal function in this disease state.

Cynodon dactylon extract as a preventive and curative agent in experimentally induced nephrolithiasis.

Science.gov (United States)

Atmani, F; Sadki, C; Aziz, M; Mimouni, M; Hacht, B

2009-04-01

Cynodon dactylon (Poaceae family) decoction was used in the treatment of kidney stones. However, no scientific study was undertaken so far to demonstrate the beneficial effect of the plant. Thus, the aim of the current study is to evaluate the effect of Cynodon aqueous extract as a preventive and curative agent in experimentally induced nephrolithiasis in a rat model. Ethylene glycol (EG) was used in the experiment to induce calcium oxalate (CaOx) deposition into kidneys. In preventive protocol, Cynodon decoction was administered in the same day with EG to evaluate the ability of the extract to prevent crystal deposition. However, in curative protocol, rats were first rendered nephrolithiasic and then the extract was administered to assess the ability of the plant to eliminate the pre-existing crystal deposition. In both protocols, urinary biochemical and other variables were measured during the course of the study. Crystalluria and renal histology were examined as well. The results showed that, in both protocols, all measured variables were similar for both the rat groups. Nevertheless, urinary biochemical analysis was apparently unaffected by the extract except oxalate in preventive protocol, and calcium, sodium, and potassium in curative protocol which were significantly highly excreted in treated rats compared to untreated animals. Crystalluria was characterized mostly by the presence of large quantities of CaOx monohydrate and CaOx dihydrate particles in untreated rats. However, crystalluria was mainly dominated by the presence of CaOx dihydrate particles with reduced size. The most apparent beneficial effect of Cynodon extract was seen in kidney tissues where reduced levels of CaOx deposition have been noticed especially in medullary and papillary sections from treated rats. We concluded that C. dactylon extract has beneficial effect in preventing and eliminating CaOx deposition into kidneys. Such findings provide a scientific explanation for its use in the

Acute phase response in two consecutive experimentally induced E. coli intramammary infections in dairy cows

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Saatsi Johanna

2008-06-01

Full Text Available Abstract Background Acute phase proteins haptoglobin (Hp, serum amyloid A (SAA and lipopolysaccharide binding protein (LBP have suggested to be suitable inflammatory markers for bovine mastitis. The aim of the study was to investigate acute phase markers along with clinical parameters in two consecutive intramammary challenges with Escherichia coli and to evaluate the possible carry-over effect when same animals are used in an experimental model. Methods Mastitis was induced with a dose of 1500 cfu of E. coli in one quarter of six cows and inoculation repeated in another quarter after an interval of 14 days. Concentrations of acute phase proteins haptoglobin (Hp, serum amyloid A (SAA and lipopolysaccharide binding protein (LBP were determined in serum and milk. Results In both challenges all cows became infected and developed clinical mastitis within 12 hours of inoculation. Clinical disease and acute phase response was generally milder in the second challenge. Concentrations of SAA in milk started to increase 12 hours after inoculation and peaked at 60 hours after the first challenge and at 44 hours after the second challenge. Concentrations of SAA in serum increased more slowly and peaked at the same times as in milk; concentrations in serum were about one third of those in milk. Hp started to increase in milk similarly and peaked at 36–44 hours. In serum, the concentration of Hp peaked at 60–68 hours and was twice as high as in milk. LBP concentrations in milk and serum started to increase after 12 hours and peaked at 36 hours, being higher in milk. The concentrations of acute phase proteins in serum and milk in the E. coli infection model were much higher than those recorded in experiments using Gram-positive pathogens, indicating the severe inflammation induced by E. coli. Conclusion Acute phase proteins would be useful parameters as mastitis indicators and to assess the severity of mastitis. If repeated experimental intramammary

Enhanced mucosal re-epithelialization induced by short chain fatty acids in experimental colitis

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Aguilar-Nascimento J.E.

1999-01-01

Full Text Available The short chain fatty acids (SCFA are the best nutrients for the colonocytes. Glucose is poorly used as a fuel but may be transformed into SCFA by colonic bacteria. The aim of this study was to investigate the effect of SCFA or glucose on experimental colitis. Colitis was induced in 30 Wistar rats by colonic instillation of 4% acetic acid. Five days later they were randomized to receive twice a day colonic lavage containing saline (controls, N = 10, 10% hypertonic glucose (N = 10 or SCFA (N = 10 until day 8 when they were killed. At autopsy, the colon was removed and weighed and the mucosa was evaluated macro- and microscopically and stripped out for DNA assay. Data are reported as mean ± SD or median [range] as appropriate. All animals lost weight but there was no difference between groups. Colon weight was significantly lower in the SCFA group (3.8 ± 0.5 g than in the control (5.3 ± 2.1 g and glucose (5.2 ± 1.3 g groups (P<0.05. Macroscopically, the severity of inflammation was less in SCFA (grade 2 [1-5] than in control (grade 9 [4-10] and glucose-treated (grade 9 [2-10] animals (P<0.01. Microscopically, ulceration of the mucosa was more severe in the glucose and control groups than in the SCFA group. The DNA content of the mucosa of SCFA-treated animals (8.2 [5.0-20.2] mg/g of tissue was higher than in glucose-treated (5.1 [4.2-8.5] mg/g of tissue; P<0.01 and control (6.2 [4.5-8.9] mg/g of tissue; P<0.05 animals. We conclude that SCFA may enhance mucosal re-epithelialization in experimental colitis, whereas hypertonic glucose is of no benefit.

Influence of serial electrical stimulations of perifornical and posterior hypothalamic orexin-containing neurons on regulation of sleep homeostasis and sleep-wakefulness cycle recovery from experimental comatose state and anesthesia-induced deep sleep.

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Chijavadze, E; Chkhartishvili, E; Babilodze, M; Maglakelidze, N; Nachkebia, N

2013-11-01

The work was aimed for the ascertainment of following question - whether Orexin-containing neurons of dorsal and lateral hypothalamic, and brain Orexinergic system in general, are those cellular targets which can speed up recovery of disturbed sleep homeostasis and accelerate restoration of sleep-wakefulness cycle phases during some pathological conditions - experimental comatose state and/or deep anesthesia-induced sleep. Study was carried out on white rats. Modeling of experimental comatose state was made by midbrain cytotoxic lesions at intra-collicular level.Animals were under artificial respiration and special care. Different doses of Sodium Ethaminal were used for deep anesthesia. 30 min after comatose state and/or deep anesthesia induced sleep serial electrical stimulations of posterior and/or perifornical hypothalamus were started. Stimulation period lasted for 1 hour with the 5 min intervals between subsequent stimulations applied by turn to the left and right side hypothalamic parts.EEG registration of cortical and hippocampal electrical activity was started immediately after experimental comatose state and deep anesthesia induced sleep and continued continuously during 72 hour. According to obtained new evidences, serial electrical stimulations of posterior and perifornical hypothalamic Orexin-containing neurons significantly accelerate recovery of sleep homeostasis, disturbed because of comatose state and/or deep anesthesia induced sleep. Speed up recovery of sleep homeostasis was manifested in acceleration of coming out from comatose state and deep anesthesia induced sleep and significant early restoration of sleep-wakefulness cycle behavioral states.

The transition time induced narrow linewidth of the electromagnetically induced transparency in caesium vapour

International Nuclear Information System (INIS)

Li Luming; Peng Xiang; Liu Cheng; Guo Hong; Chen Xuzong

2004-01-01

We observed a narrow linewidth (∼60 kHz) in a Doppler-broadened system showing electromagnetically induced transparency in caesium atomic vapour. The transition time induced reduction of the linewidth is illustrated both theoretically and experimentally

Experimental setup and first measurement of DNA damage induced along and around an antiproton beam

DEFF Research Database (Denmark)

Kavanagh, J. N.; Currell, F. J.; Timson, D. J.

2010-01-01

a further enhancement due to their annihilation at the end of the path. The work presented here aimed to establish and validate an experimental procedure for the quantification of plasmid and genomic DNA damage resulting from antiproton exposure. Immunocytochemistry was used to assess DNA damage in directly......Radiotherapy employs ionizing radiation to induce lethal DNA lesions in cancer cells while minimizing damage to healthy tissues. Due to their pattern of energy deposition, better therapeutic outcomes can, in theory, be achieved with ions compared to photons. Antiprotons have been proposed to offer...... and indirectly exposed human fibroblasts irradiated in both plateau and Bragg peak regions of a 126 MeV antiproton beam at CERN. Cells were stained post irradiation with an anti-γ-H2AX antibody. Quantification of the γ-H2AX foci-dose relationship is consistent with a linear increase in the Bragg peak region...

Experimental Investigation Of Microbially Induced Corrosion Of Test Samples And Effect Of Self-assembled Hydrophobic Monolayers. Exposure Of Test Samples To Continuous Microbial Cultures, Chemical Analysis, And Biochemical Studies

CERN Document Server

Laurinavichius, K S

1998-01-01

Experimental Investigation Of Microbially Induced Corrosion Of Test Samples And Effect Of Self-assembled Hydrophobic Monolayers. Exposure Of Test Samples To Continuous Microbial Cultures, Chemical Analysis, And Biochemical Studies

Helichrysum plicatum DC. subsp. plicatum extract as a preventive agent in experimentally induced urolithiasis model.

Science.gov (United States)

Bayir, Yasin; Halici, Zekai; Keles, Mevlut Sait; Colak, Suat; Cakir, Ahmet; Kaya, Yusuf; Akçay, Fatih

2011-11-18

Since ancient times, various herbal preparations have been used in treatment of urolithiasis, which is basically formation of calcium oxalate stones in kidney. The aim of our study is to assess the effects of Helichrysum plicatum DC. subsp. plicatum (HP) as a preventive agent in experimentally induced urolithiasis model in rats. The efficacy of 125, 250, and 500 mg/kg HP extract was studied in 1% ethylene glycol and 1% ammonium chloride-induced urolithiasis for 21 days in rats. The weight difference and the levels of calcium, magnesium, phosphorus, urea nitrogen, creatinine and uric acid in both serum and 24h-urine were measured. The calcium oxalate (CaOx) and pH were defined in urine. Histo-pathological analyses in kidneys were also performed. The rats' weights were higher in HP groups than urolithiasis group. Urolithiasis caused a significant increase in both serum and urine biochemical parameters compared to healthy rats. HP extract decreased levels of these parameters. Urine CaOx level was high in urolithiasis rats, whereas it was decreased by HP extract. Histopathological examinations revealed extensive intratubular crystal depositions and degenerative tubular structures in urolithiasis group, but not in HP treatment groups. More studies will be necessary to elucidate the antiurolithiatic activity of HP. Nonetheless, having a beneficial effect in preventing and eliminating CaOx deposition into kidneys, HP extract may be a potential drug for urolithiasis treatment. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Resveratrol protects from lipopolysaccharide-induced inflammation in the uterus and prevents experimental preterm birth.

Science.gov (United States)

Bariani, María Victoria; Correa, Fernando; Leishman, Emma; Domínguez Rubio, Ana Paula; Arias, Andreína; Stern, Aníbal; Bradshaw, Heather B; Franchi, Ana María

2017-08-01

pregnant BALB/c mice with resveratrol prevented the LPS-induced preterm birth in 64% of the cases, whereas only 15% of mice with LPS alone escaped preterm birth. Treatment with resveratrol resulted in a reduced NOS activity (P resveratrol reduced the expression of LPS-induced pro-inflammatory agents such as iNOS (P resveratrol administration resulted in changes in the uterine endocannabinoid profiling altered by LPS. N/A. Since our experimental design involves the use of mice, the extrapolation of the results presented here to humans is limited. Our findings provide evidence for the tocolytic effects of resveratrol. Dr Ana María Franchi was funded by Agencia Nacional para la Promoción Científica y Tecnológica (PICT 2013/0097) and by Consejo Nacional de Investigaciones Científicas y Técnicas (PIP 2012/0061). Dr Heather B. Bradshaw was funded by NIH (DA006668). The authors have no competing interests. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Women with dysmenorrhoea are hypersensitive to experimentally induced forearm ischaemia during painful menstruation and during the pain-free follicular phase.

Science.gov (United States)

Iacovides, S; Avidon, I; Baker, F C

2015-07-01

Monthly primary dysmenorrhoeic pain is associated with increased sensitivity to painful stimuli, particularly in deep tissue. We investigated whether women with dysmenorrhoea, compared with controls, have increased sensitivity to experimentally induced deep-tissue muscle ischaemia in a body area distant from that of referred menstrual pain. The sub-maximal effort tourniquet test was used to induce forearm ischaemia in 11 women with severe dysmenorrhoea and in nine control women both during menstruation and in the follicular phase of the menstrual cycle. Von Frey hair assessments confirmed the presence of experimental ischaemia. Women rated the intensity of menstrual and ischaemic pain on a 100-mm visual analogue scale. Women with dysmenorrhoea [mean (SD): 68 (20) mm] reported significantly greater menstrual pain compared with controls [mean (SD): 2 (6) mm; p = 0.0001] during the menstruation phase. They also rated their forearm ischaemic pain as significantly greater than the controls during the menstruation [dysmenorrhoeics vs. controls mean (SD): 58 (19) mm vs. 31 (21) mm, p menstruation phase and pain-free follicular phase. These findings suggest the presence of long-lasting changes in muscle pain sensitivity in women with dysmenorrhoea. Our findings that dysmenorrhoeic women are hyperalgesic to a clinically relevant, deep-muscle ischaemic pain in areas outside of referred menstrual pain confirm other studies showing long-lasting changes in pain sensitivity outside of the painful period during menstruation. © 2014 European Pain Federation - EFIC®

Tobacco experimental model to induce urinary bladder neoplasms

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José Alexandre Colli Neto

2014-01-01

Full Text Available OBJECTIVE: to develop an experimental model of exposure to tobacco burning (cigarette products to assess the effects of its chronic use in relation to cancers of the bladder. METHODS: the animals were chronically exposed to the burning tobacco products in a semi-open chamber to simulate smoking. Thirty young Wistar rats were divided into two groups: one with 20 animals simulating smoking for six months, and ten not exposed control animals for the same period. After exposure by inhalation of cigarette smoke, animals were euthanized and subjected to histopathological study of the bladder wall. RESULTS: no tumor was found but mild and non significant alterations. The studies of hemo-oximetry (carboxyhemoglobin and methemoglobin and the concentration of carbon dioxide (CO2 confirm that the animals were exposed to high concentrations of tobacco smoke and its derivatives. CONCLUSION: no bladder mucosal neoplasia was found in the pathological study of animals. The developed experimental models were highly efficient, practical and easy to use and can be used in other similar studies to determine the harmful effects caused by smoking.

Determination of ultra-short laser induced damage threshold of KH{sub 2}PO{sub 4} crystal: Numerical calculation and experimental verification

Energy Technology Data Exchange (ETDEWEB)

Cheng, Jian [Center for Precision Engineering, School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001 (China); Department of Physics, The Ohio State University, 191 W. Woodruff Ave, Columbus, OH 43210 (United States); Chen, Mingjun, E-mail: chenmj@hit.edu.cn, E-mail: chowdhury.24@osu.edu; Wang, Jinghe; Xiao, Yong [Center for Precision Engineering, School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001 (China); Kafka, Kyle; Austin, Drake; Chowdhury, Enam, E-mail: chenmj@hit.edu.cn, E-mail: chowdhury.24@osu.edu [Department of Physics, The Ohio State University, 191 W. Woodruff Ave, Columbus, OH 43210 (United States)

2016-03-15

Rapid growth and ultra-precision machining of large-size KDP (KH{sub 2}PO{sub 4}) crystals with high laser damage resistance are tough challenges in the development of large laser systems. It is of high interest and practical significance to have theoretical models for scientists and manufacturers to determine the laser-induced damage threshold (LIDT) of actually prepared KDP optics. Here, we numerically and experimentally investigate the laser-induced damage on KDP crystals in ultra-short pulse laser regime. On basis of the rate equation for free electron generation, a model dedicated to predicting the LIDT is developed by considering the synergistic effect of photoionization, impact ionization and decay of electrons. Laser damage tests are performed to measure the single-pulse LIDT with several testing protocols. The testing results combined with previously reported experimental data agree well with those calculated by the model. By taking the light intensification into consideration, the model is successfully applied to quantitatively evaluate the effect of surface flaws inevitably introduced in the preparation processes on the laser damage resistance of KDP crystals. This work can not only contribute to further understanding of the laser damage mechanisms of optical materials, but also provide available models for evaluating the laser damage resistance of exquisitely prepared optical components used in high power laser systems.

Experimentally nonylphenol-polluted diet induces the expression of silent genes VTG and ERα in the liver of male lizard Podarcis sicula

International Nuclear Information System (INIS)

Verderame, Mariailaria; Prisco, Marina; Andreuccetti, Piero; Aniello, Francesco; Limatola, Ermelinda

2011-01-01

Endocrine Disruptor Chemicals (EDCs) with estrogen-like properties i.e nonylphenol (NP) induce vitellogenin (VTG) synthesis in males of aquatic and semi-aquatic specie. In the oviparous species VTG is a female-specific oestrogen dependent protein. Males are unable to synthesize VTG except after E 2 treatment. This study aimed to verify if NP, administered via food and water, is able to induce the expression of VTG even in males of vertebrates with a terrestrial habitat such as the lizard Podarcis. By means of ICC, ISH, W/B and ELISA we demonstrated that NP induces the presence of VTG in the plasma and its expression in the liver. VTG, undetectable in untreated males, reaches the value of 4.34 μg/μl in the experimental ones. Expression analysis and ISH in the liver showed that an NP-polluted diet also elicits the expression of ERα in the liver which is known to be related to VTG synthesis in Podarcis. - Highlights: → Nonylphenol (NP) polluted diet induces VTG synthesis in a terrestrial vertebrate. → VTG and ERα genes are unexpressed in the liver of untreated male lizards Podarcis. → In the liver cells of NP-treated males the expression of both VTG and ERα occurs. → In treated males VTG synthesis is coupled with ERα expression as in breeding females. - NP-polluted diet induces the expression of ERα and VTG in the liver.

Experimental comparison of models for ultrafast impact ionization is silicon

DEFF Research Database (Denmark)

Tarekegne, Abebe Tilahun; Iwaszczuk, Krzysztof; Jepsen, Peter Uhd

2016-01-01

We compare experimentally the exponential and quadratic (Keldysh formula) impact ionization models using THz induced impact ionization in silicon. We demonstrate that the exponential model offers the best description of impact ionization process for ultrashort electric filed pulses.......We compare experimentally the exponential and quadratic (Keldysh formula) impact ionization models using THz induced impact ionization in silicon. We demonstrate that the exponential model offers the best description of impact ionization process for ultrashort electric filed pulses....

Application of metabonomics on an experimental model of fibrosis and cirrhosis induced by thioacetamide in rats

International Nuclear Information System (INIS)

Constantinou, Maria A.; Theocharis, Stamatios E.; Mikros, Emmanuel

2007-01-01

Metabonomics has already been used to discriminate different pathological states in biological fields. The metabolic profiles of chronic experimental fibrosis and cirrhosis induction in rats were investigated using 1 H NMR spectroscopy of liver extracts and serum combined with pattern recognition techniques. Rats were continuously administered with thioacetamide (TAA) in the drinking water (300 mg TAA/L), and sacrificed on 1st, 2nd, and 3rd month of treatment. 1 H NMR spectra of aqueous and lipid liver extracts, together with serum were subjected to Principal Component Analysis (PCA). Liver portions were also subjected to histopathological examination and biochemical determination of malondialdehyde (MDA). Liver fibrosis and cirrhosis were progressively induced in TAA-treated rats, verified by the histopathological examination and the alterations of MDA levels. TAA administration revealed a number of changes in the 1 H NMR spectra compared to control samples. The performance of PCA in liver extracts and serum, discriminated the control samples from the fibrotic and cirrhotic ones. Metabolic alterations revealed in NMR spectra during experimental liver fibrosis and cirrhosis induction, characterize the stage of fibrosis and could be illustrated by subsequent PCA of the spectra. Additionally, the PCA plots of the serum samples presented marked clustering during fibrosis progression and could be extended in clinical diagnosis for the management of cirrhotic patients

Experimental intrauterine growth retardation.

Science.gov (United States)

van Marthens, E; Harel, S; Zamenshof, S

1975-01-01

The effects of experimental intrauterine growth retardation on subsequent fetal development, especially with respect to brain development, were studied in a new animal model. The rabbit was chosen since it has a perinatal pattern of brain development similar to that of the human. Experimental ischemia was induced during the last trimester by ligation of spiral arterioles and the differential effects on fetal development at term (30th gestational day) are reported. Specific brain regions were examined for wet weight, total cell number (DNA) and total protein content. Highly significant decreases in all these parameters were found in both the cortex and cerebellum following experimental intrauterine growth retardation; these two organs were differentially affected. The prospects and advantages of using this animal model for the study of the postnatal "catch-up growth" are discussed.

Experimental Warming Aggravates Degradation-Induced Topsoil Drought in Alpine Meadows of The Qinghai-Tibetan Plateau

Science.gov (United States)

Xue, X.

2017-12-01

Climatic warming is presumed to cause topsoil drought by increasing evapotranspiration and water infiltration, and by progressively inducing land degradation in alpine meadows of the Qinghai-Tibetan Plateau. However, how soil moisture and temperature patterns of degraded alpine meadows respond to climate warming remains unclear. A six-year continuous warming experiment was carried out in both degraded and undegraded alpine meadows in the source region of the Yangtze River. The goal was to identify the effects of climatic warming and land degradation on soil moisture (θ), soil surface temperature (Tsfc), and soil temperature (Ts). In the present study, land degradation significantly reduced θ by 4.5-6.1% at a depth of 0-100 cm (P soil surface. Experimental warming aggravated topsoil drought caused by land degradation, intensified the magnitude of degradation, and caused a positive feedback in the degraded alpine meadow ecosystem. Therefore, an immediate need exists to restore degraded alpine meadow grasslands in the Qinghai-Tibetan Plateau in anticipation of a warmer future.

Sumoylation of hypoxia-inducible factor-1α ameliorates failure of brain stem cardiovascular regulation in experimental brain death.

Directory of Open Access Journals (Sweden)

Julie Y H Chan

2011-03-01

Full Text Available One aspect of brain death is cardiovascular deregulation because asystole invariably occurs shortly after its diagnosis. A suitable neural substrate for mechanistic delineation of this aspect of brain death resides in the rostral ventrolateral medulla (RVLM. RVLM is the origin of a life-and-death signal that our laboratory detected from blood pressure of comatose patients that disappears before brain death ensues. At the same time, transcriptional upregulation of heme oxygenase-1 in RVLM by hypoxia-inducible factor-1α (HIF-1α plays a pro-life role in experimental brain death, and HIF-1α is subject to sumoylation activated by transient cerebral ischemia. It follows that sumoylation of HIF-1α in RVLM in response to hypoxia may play a modulatory role on brain stem cardiovascular regulation during experimental brain death.A clinically relevant animal model that employed mevinphos as the experimental insult in Sprague-Dawley rat was used. Biochemical changes in RVLM during distinct phenotypes in systemic arterial pressure spectrum that reflect maintained or defunct brain stem cardiovascular regulation were studied. Western blot analysis, EMSA, ELISA, confocal microscopy and immunoprecipitation demonstrated that drastic tissue hypoxia, elevated levels of proteins conjugated by small ubiquitin-related modifier-1 (SUMO-1, Ubc9 (the only known conjugating enzyme for the sumoylation pathway or HIF-1α, augmented sumoylation of HIF-1α, nucleus-bound translocation and enhanced transcriptional activity of HIF-1α in RVLM neurons took place preferentially during the pro-life phase of experimental brain death. Furthermore, loss-of-function manipulations by immunoneutralization of SUMO-1, Ubc9 or HIF-1α in RVLM blunted the upregulated nitric oxide synthase I/protein kinase G signaling cascade, which sustains the brain stem cardiovascular regulatory machinery during the pro-life phase.We conclude that sumoylation of HIF-1α in RVLM ameliorates brain stem

Effects of intravenous hyperosmotic sodium bicarbonate on arterial and cerebrospinal fluid acid-base status and cardiovascular function in calves with experimentally induced respiratory and strong ion acidosis.

Science.gov (United States)

Berchtold, Joachim F; Constable, Peter D; Smith, Geoffrey W; Mathur, Sheerin M; Morin, Dawn E; Tranquilli, William J

2005-01-01

The objectives of this study were to determine the effects of hyperosmotic sodium bicarbonate (HSB) administration on arterial and cerebrospinal fluid (CSF) acid-base balance and cardiovascular function in calves with experimentally induced respiratory and strong ion (metabolic) acidosis. Ten healthy male Holstein calves (30-47 kg body weight) were instrumented under halothane anesthesia to permit cardiovascular monitoring and collection of blood samples and CSE Respiratory acidosis was induced by allowing the calves to spontaneously ventilate, and strong ion acidosis was subsequently induced by i.v. administration of L-lactic acid. Calves were then randomly assigned to receive either HSB (8.4% NaHCO3; 5 ml/kg over 5 minutes, i.v.; n=5) or no treatment (controls, n=5) and monitored for 1 hour. Mixed respiratory and strong ion acidosis was accompanied by increased heart rate, cardiac index, mean arterial pressure, cardiac contractility (maximal rate of change of left ventricular pressure), and mean pulmonary artery pressure. Rapid administration of HSB immediately corrected the strong ion acidosis, transiently increased arterial partial pressure of carbon dioxide (P(CO2)), and expanded the plasma volume. The transient increase in arterial P(CO2) did not alter CSF P(CO2) or induce paradoxical CSF acidosis. Compared to untreated control calves, HSB-treated calves had higher cardiac index and contractility and a faster rate of left ventricular relaxation for 1 hour after treatment, indicating that HSB administration improved myocardial systolic function. We conclude that rapid i.v. administration of HSB provided an effective and safe method for treating strong ion acidosis in normovolemic halothane-anesthetized calves with experimentally induced respiratory and strong ion acidosis. Fear of inducing paradoxical CSF acidosis is not a valid reason for withholding HSB administration in calves with mixed respiratory and strong ion acidosis.

Extension of the energy range of experimental activation cross-sections data of deuteron induced nuclear reactions on indium up to 50MeV.

Science.gov (United States)

Tárkányi, F; Ditrói, F; Takács, S; Hermanne, A; Ignatyuk, A V

2015-11-01

The energy range of our earlier measured activation cross-sections data of longer-lived products of deuteron induced nuclear reactions on indium were extended from 40MeV up to 50MeV. The traditional stacked foil irradiation technique and non-destructive gamma spectrometry were used. No experimental data were found in literature for this higher energy range. Experimental cross-sections for the formation of the radionuclides (113,110)Sn, (116m,115m,114m,113m,111,110g,109)In and (115)Cd are reported in the 37-50MeV energy range, for production of (110)Sn and (110g,109)In these are the first measurements ever. The experimental data were compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS 1.6 nuclear model code as listed in the on-line library TENDL-2014. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ab-initio modeling of an iron laser-induced plasma: Comparison between theoretical and experimental atomic emission spectra

International Nuclear Information System (INIS)

Colgan, J.; Judge, E.J.; Kilcrease, D.P.; Barefield, J.E.

2014-01-01

We report on efforts to model the Fe emission spectrum generated from laser-induced breakdown spectroscopy (LIBS) measurements on samples of pure iron oxide (Fe 2 O 3 ). Our modeling efforts consist of several components. We begin with ab-initio atomic structure calculations performed by solving the Hartree–Fock equations for the neutral and singly ionized stages of Fe. Our energy levels are then adjusted to their experimentally known values. The atomic transition probabilities and atomic collision quantities are also computed in an ab-initio manner. We perform LTE or non-LTE calculations that generate level populations and, subsequently, an emission spectrum for the iron plasma for a range of electron temperatures and electron densities. Such calculations are then compared to the experimental spectrum. We regard our work as a preliminary modeling effort that ultimately strives towards the modeling of emission spectra from even more complex samples where less atomic data are available. - Highlights: • LIBS plasma of iron oxide • Ab-initio theoretical Modeling • Discussion of LTE versus non-LTE criteria and assessment • Boltzmann plots for Fe—determination of when LTE is a valid assumption • Emission spectra for Fe—comparison of theoretical modeling and measurement: good agreement obtained

Experimental evaluation of neural probe’s insertion induced injury based on digital image correlation method

Energy Technology Data Exchange (ETDEWEB)

Zhang, Wenguang, E-mail: zhwg@sjtu.edu.cn; Ma, Yakun; Li, Zhengwei [State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 200240 (China)

2016-01-15

Purpose: The application of neural probes in clinic has been challenged by probes’ short lifetime when implanted into brain tissue. The primary goal is to develop an evaluation system for testing brain tissue injury induced by neural probe’s insertion using microscope based digital image correlation method. Methods: A brain tissue phantom made of silicone rubber with speckle pattern on its surface was fabricated. To obtain the optimal speckle pattern, mean intensity gradient parameter was used for quality assessment. The designed testing system consists of three modules: (a) load module for simulating neural electrode implantation process; (b) data acquisition module to capture micrographs of speckle pattern and to obtain reactive forces during the insertion of the probe; (c) postprocessing module for extracting tissue deformation information from the captured speckle patterns. On the basis of the evaluation system, the effects of probe wedge angle, insertion speed, and probe streamline on insertion induced tissue injury were investigated. Results: The optimal quality speckle pattern can be attained by the following fabrication parameters: spin coating rate—1000 r/min, silicone rubber component A: silicone rubber component B: softener: graphite = 5 ml: 5 ml: 2 ml: 0.6 g. The probe wedge angle has a significant effect on tissue injury. Compared to wedge angle 40° and 20°, maximum principal strain of 60° wedge angle was increased by 40.3% and 87.5%, respectively; compared with a relatively higher speed (500 μm/s), the maximum principle strain within the tissue induced by slow insertion speed (100 μm/s) was increased by 14.3%; insertion force required by probe with convex streamline was smaller than the force of traditional probe. Based on the experimental results, a novel neural probe that has a rounded tip covered by a biodegradable silk protein coating with convex streamline was proposed, which has both lower insertion and micromotion induced tissue

Low dose radiation induced protein and its experimental and ophthalmic clinical research

International Nuclear Information System (INIS)

Shen Wei; Su Liaoyuan; Liu Fenju; Ding Jie; Li Longbiao; Pan Chengsi

2001-01-01

The protective effects of low dose radiation (LDR) induced protein on cellular impairments caused by some harmful chemical and physical factors were studied. Male Kunming mice were irradiated with LDR, then the spleen cells of the mice were broken with ultrasonic energy and then ultracentrifugalized. The supernatant solution contained with LDR induced protein. The newly emerging protein was detected by gel filtration and its molecular weight was determined by gel electrophoresis. The content of newly emerging protein (LDR induced protein) was determined by Lowry's method. The method of isotope incorporation was used to observe the biological activity and its influence factors, the protective effects of LDR induced protein on the cells impaired by irradiating with ultraviolet (UV), high doses of 60 Co γ-rays and exposed to heat respectively, and the stimulative effects of LDR induced protein on human peripheral blood lymphocytes. Newly emerging protein has been observed in the experiment. The molecular weight of the protein is in the region 76.9 KD+- - 110.0 KD+-, the yield of the protein was 613.33 +- 213.42 μg per 3 x 10 7 spleen cells. DPM values (isotope were incorporated) of normal and injured mice spleen cells increased significantly after stimulating with the solution contained LDR induced protein. It is concluded that LDR induced protein could be obtained from mice spleen cells exposed to 5 - 15 cGy radiation for 2 - 16 h. The protein had biological activity and was able to stimulate the transformation of the spleen cells in vitro. It had obvious protective effects on some impaired cells caused by high dose radiation, UV radiation, heat and so on. It also had stimulative effects on the transformation of peripheral blood T and B lymphocytes of healthy individual and patients with eye diseases. It indicates that LDR induced protein increased immune function of human

Wild Vervet Monkeys Trade Tolerance and Specific Coalitionary Support for Grooming in Experimentally Induced Conflicts.

Science.gov (United States)

Borgeaud, Christèle; Bshary, Redouan

2015-11-16

Grooming is a key social behavior in many primate species. Research has focused on three important aspects: the short- and long-term trading patterns of grooming for itself and/or for other commodities like tolerance or coalitionary support, the issue of whether exchanges are a convincing example for reciprocity, and what decision rules underlie trading. These issues remain largely unresolved due to the correlative nature of observational studies and the rarity of experimental studies. Here, we present a new experimental paradigm to address these questions in wild vervet monkeys (Chlorocebus pygerythrus). Adult females were first trained to approach a personal box, identifiable by unique color patterns, to access high-quality food. During the experiments, two boxes were placed next to each other to induce conflict through forced proximity. We found that while dominants were generally more tolerant toward bonded individuals, recent grooming increased tolerance independently of relationship quality. The latter result shows that vervet monkeys traded grooming for short-term tolerance, where dominants used a direct-reciprocity decision rule. In contrast, females invariably supported the higher-ranking opponent in a conflict, independently of who was the recent grooming partner. Nevertheless, recent grooming increased the probability that a female supported the partner during conflicts with a low-ranking third party. Thus, females' decisions about coalitionary support seem to integrate information about the current social hierarchy with recent grooming events. In conclusion, decision rules underlying trading of grooming for other commodities involve a variety of timescales and factors. Copyright © 2015 Elsevier Ltd. All rights reserved.

Experimental application of QCD antennas

Energy Technology Data Exchange (ETDEWEB)

Bobrovskyi, Sergei

2010-02-15

A serious problem in searches for new physics at the LHC is the rejection of QCD induced multijet events. In this thesis the formalism of QCD antenna variables based on the SPHEL approximation of QCD matrix elements is applied for the rst time on experimentally reconstructed jets in order to discriminate QCD from supersymmetric processes. The new observables provide additional information with respect to traditional event shape variables. Albeit correlated with experimentally measured missing transverse energy, the variables can be used to improve the signal to background ratio. (orig.)

Experimental application of QCD antennas

International Nuclear Information System (INIS)

Bobrovskyi, Sergei

2010-02-01

A serious problem in searches for new physics at the LHC is the rejection of QCD induced multijet events. In this thesis the formalism of QCD antenna variables based on the SPHEL approximation of QCD matrix elements is applied for the rst time on experimentally reconstructed jets in order to discriminate QCD from supersymmetric processes. The new observables provide additional information with respect to traditional event shape variables. Albeit correlated with experimentally measured missing transverse energy, the variables can be used to improve the signal to background ratio. (orig.)

A Systematic Review of Experimental and Clinical Acupuncture in Chemotherapy-Induced Peripheral Neuropathy

Directory of Open Access Journals (Sweden)

Giovanna Franconi

2013-01-01

Full Text Available Chemotherapy-induced peripheral neuropathy (CIPN is a common side effect that can be very disabling and can limit or delay the dose of chemotherapy that can be administered. Acupuncture may be effective for treating peripheral neuropathy. The aim of this study was to review the available literature on the use of acupuncture for CIPN. The systematic literature search was performed using MEDLINE, Google Scholar, Cochrane Database, CINHAL, and ISI Proceedings. Hand searching was conducted, and consensus was reached on all extracted data. Only papers in the English language were included, irrespective of study design. From 3989 retrieved papers, 8 relevant papers were identified. One was an experimental study which showed that electroacupuncture suppressed CIPN pain in rats. In addition, there were 7 very heterogeneous clinical studies, 1 controlled randomised study using auricular acupuncture, 2 randomized controlled studies using somatic acupuncture, and 3 case series/case reports which suggested a positive effect of acupuncture in CIPN. Conclusions. Only one controlled randomised study demonstrated that acupuncture may be beneficial for CIPN. All the clinical studies reviewed had important methodological limitations. Further studies with robust methodology are needed to demonstrate the role of acupuncture for treating CIPN resulting from cancer treatment.

Current status of antiproton impact ionization of atoms and molecules: theoretical and experimental perspectives

DEFF Research Database (Denmark)

Kirchner, Tom; Knudsen, Helge

2011-01-01

Experimental and theoretical progress in the field of antiproton-impact-induced ionization of atoms and molecules is reviewed. We describe the techniques used to measure ionization cross sections and give an overview of the experimental results supplemented by tables of all existing data. An atte......Experimental and theoretical progress in the field of antiproton-impact-induced ionization of atoms and molecules is reviewed. We describe the techniques used to measure ionization cross sections and give an overview of the experimental results supplemented by tables of all existing data...

Host response in bovine mastitis experimentally induced with Staphylococcus chromogenes.

Science.gov (United States)

Simojoki, H; Orro, T; Taponen, S; Pyörälä, S

2009-02-16

An experimental infection model was developed to study host response to intramammary infection in cows caused by Staphylococcus chromogenes. CNS intramammary infections have become very common in modern dairy herds, and they can remain persistent in the mammary gland. More information would be needed about the pathophysiology of CNS mastitis, and an experimental mastitis model is a means for this research. Six primiparous Holstein-Friesian cows were challenged with S. chromogenes 4 weeks after calving. One udder quarter of each cow was inoculated with 2.1 x 10(6)cfu of S. chromogenes. All cows became infected and clinical signs were mild. Milk production of the challenged quarter decreased on average by 16.3% during 7 days post-challenge. Cows eliminated bacteria in a few days, except for one cow which developed persistent mastitis. Milk indicators of inflammation, SCC and N-acetyl-beta-D-glucosaminidase (NAGase) returned to normal within a week. Milk NAGase activity increased moderately, which reflects minor tissue damage in the udder. Concentrations of serum amyloid A (SAA) and milk amyloid A (MAA) were both elevated at 12h PC. MAA was affected by the milking times, and was at its highest before the morning milking. In our experimental model, systemic acute phase protein response with SAA occurred as an on-off type reaction. In conclusion, this experimental model could be used to study host response in CNS mastitis caused by the main CNS species and also for comparison of the host response in a mild intramammary infection and in more severe mastitis models.

Experimental investigation of localized stress-induced leakage current distribution in gate dielectrics using array test circuit

Science.gov (United States)

Park, Hyeonwoo; Teramoto, Akinobu; Kuroda, Rihito; Suwa, Tomoyuki; Sugawa, Shigetoshi

2018-04-01

Localized stress-induced leakage current (SILC) has become a major problem in the reliability of flash memories. To reduce it, clarifying the SILC mechanism is important, and statistical measurement and analysis have to be carried out. In this study, we applied an array test circuit that can measure the SILC distribution of more than 80,000 nMOSFETs with various gate areas at a high speed (within 80 s) and a high accuracy (on the 10-17 A current order). The results clarified that the distributions of localized SILC in different gate areas follow a universal distribution assuming the same SILC defect density distribution per unit area, and the current of localized SILC defects does not scale down with the gate area. Moreover, the distribution of SILC defect density and its dependence on the oxide field for measurement (E OX-Measure) were experimentally determined for fabricated devices.

Experimentally nonylphenol-polluted diet induces the expression of silent genes VTG and ER{alpha} in the liver of male lizard Podarcis sicula

Energy Technology Data Exchange (ETDEWEB)

Verderame, Mariailaria; Prisco, Marina; Andreuccetti, Piero [Department of Biological Sciences, Evolutionary and Comparative Biology Division, University Federico II of Naples, Via Mezzocannone 8, 80134 Naples (Italy); Aniello, Francesco [Department of Biological Sciences, Genetic and Molecular Biology Division, University Federico II of Naples, Via Mezzocannone 8, 80134 Naples (Italy); Limatola, Ermelinda, E-mail: limatola@unina.it [Department of Biological Sciences, Evolutionary and Comparative Biology Division, University Federico II of Naples, Via Mezzocannone 8, 80134 Naples (Italy)

2011-05-15

Endocrine Disruptor Chemicals (EDCs) with estrogen-like properties i.e nonylphenol (NP) induce vitellogenin (VTG) synthesis in males of aquatic and semi-aquatic specie. In the oviparous species VTG is a female-specific oestrogen dependent protein. Males are unable to synthesize VTG except after E{sub 2} treatment. This study aimed to verify if NP, administered via food and water, is able to induce the expression of VTG even in males of vertebrates with a terrestrial habitat such as the lizard Podarcis. By means of ICC, ISH, W/B and ELISA we demonstrated that NP induces the presence of VTG in the plasma and its expression in the liver. VTG, undetectable in untreated males, reaches the value of 4.34 {mu}g/{mu}l in the experimental ones. Expression analysis and ISH in the liver showed that an NP-polluted diet also elicits the expression of ER{alpha} in the liver which is known to be related to VTG synthesis in Podarcis. - Highlights: > Nonylphenol (NP) polluted diet induces VTG synthesis in a terrestrial vertebrate. > VTG and ER{alpha} genes are unexpressed in the liver of untreated male lizards Podarcis. > In the liver cells of NP-treated males the expression of both VTG and ER{alpha} occurs. > In treated males VTG synthesis is coupled with ER{alpha} expression as in breeding females. - NP-polluted diet induces the expression of ER{alpha} and VTG in the liver.

Experimental study on the fragmentation of Adenine and Porphyrin molecules induced by low energy multicharged ion impact

International Nuclear Information System (INIS)

Li, B.

2010-01-01

Since the dissociation of small molecules might play key roles in the understanding of radiation induced damages of living tissues at the primary steps and at the molecular levels, fragmentation dynamics of small biomolecules have drawn much attention. The knowledge of the internal energy is of fundamental importance for understanding its fragmentation dynamics following external excitation. For a long time however, it was difficult to measure this parameter in coincidence with the fragmentation patterns until the development of CIDEC (Collision Induced Dissociation under Energy Control) method in 2007. In this work, the CIDEC method was extended to study the fragmentation of gas-phase biomolecules adenine (Ade: H 5 C 5 N 5 ) and porphyrin chloride FeTPPCl (C 44 H 28 N 4 FeCl). The population distribution for each dissociation channel as a function of the excitation energy of the parent molecular ions at a well-determined initial charge state has been experimentally determined, which could shed some light on the fragmentation dynamics of these molecules. In collisions between Cl + and Ade at 3 keV, the fragmentation pattern of Ade 2+ is dominated by the loss of H 2 CN + and the successive emission of HCN. The energy distribution of the parent dication confirms the successive emission dynamics. A specific decay channel is observed, i.e. the emission of a charged H 2 CN + followed by the emission of HC 2 N 2 . The measured mean excitation energies of this channel and other competitive channels are compared. In Kr 8+ - FeTPPCl collisions at 80 keV, parent ions FeTPPCL 1+,2+,3+ are observed, along with the corresponding decay patterns. It is found that, in the first step the dominant low-energy-cost decay channel is the emission of Cl 0 independent of the initial charge state of FeTPPCl r+ . For the resulted dication FeTPP 2+ , the dominant fragmentation channel is the neutral evaporation; for the tri-cation however, the dominant fragmentation channel is the

Piracetam Facilitates the Anti-Amnesic but not Anti-Diabetic Activity of Metformin in Experimentally Induced Type-2 Diabetic Encephalopathic Rats.

Science.gov (United States)

Pandey, Shruti; Garabadu, Debapriya

2017-07-01

Piracetam exhibits anti-amnesic activity in several animal models of dementia. However, its anti-amnesic potential has yet to be evaluated in type-2 diabetes mellitus (T2DM)-induced encephalopathy. Therefore, in the present study, piracetam (25, 50 and 100 mg/kg) was screened for anti-amnesic and anti-diabetic activity in T2DM-induced encephalopathic male rats. Subsequently, anti-amnesic and anti-diabetic activities were evaluated for piracetam, metformin and their combination in T2DM-induced encephalopathic animals. Rats received streptozotocin (45 mg/kg) and nicotinamide (110 mg/kg) injections on day-1 (D-1) of the experimental schedule and were kept undisturbed for 35 days to exhibit T2DM-induced encephalopathy. All drug treatments were continued from D-7 to D-35 in both experiments. Piracetam (100 mg/kg) attenuated loss in learning and memory in terms of increase in escape latency on D-4 (D-34) and decrease in time spent in the target quadrant on D-5 (D-35) of Morris water maze test protocol, and spatial memory in terms of reduced spontaneous alternation behavior in Y-maze test of encephalopathic rats. Additionally, piracetam attenuated altered levels of fasting plasma glucose and insulin, HOMA-IR and HOMA-B in encephalopathic animals, comparatively lesser than metformin. In the next experiment, combination of piracetam and metformin exhibited better anti-amnesic but not anti-diabetic activity than respective monotherapies in encephalopathic rats. Further, the combination attenuated reduced acetylcholine level and increased acetylcholinesterase activity, increased glycogen synthase kinase-3β level and decreased brain-derived neurotropic factor level in hippocampus and pre-frontal cortex of encephalopathic animals. Thus, piracetam could be used as an adjuvant to metformin in the management of dementia in T2DM-induced encephalopathy.

Comparative study of the effects of experimentally induced hypothyroidism and hyperthyroidism in some brain regions in albino rats.

Science.gov (United States)

El-Bakry, A M; El-Gareib, A W; Ahmed, R G

2010-08-01

Thyroid hormones (THs) play a crucial role in the development and physiological functioning of different body organs especially the brain. Therefore, the objective of this study was to show the histopathological effects of the different thyroid states on some brain regions (cerebrum and cerebellum) and the skeletal features of their newborns during the postnatal development from the 1st to 3rd week. The female white albino rats were allocated into 3 groups as follows: the experimental hypothyroidism group is induced by 0.02% methimazole (MMI) (w/v) in drinking water, while the experimental hyperthyroidism group is performed by exogenous T4 [from 50 to 200microg/kg body weight intragastric administration beside adding 0.002% T4 (w/v) to the drinking water] from the gestation day 1 to lactation day 21 and control group which received tap water. As well, both maternal hypo- and hyperthyroidism caused some malformation and developmental defects in the cerebellar and cerebral cortex of their newborns along the duration of the experiment. These degenerative symptoms became more prominent and widely spread at the 3rd postnatal week. Concomitantly, there were some degeneration, deformation and severe growth retardation in neurons of these regions in both treated groups throughout the experimental period. Moreover, the skeletal features of these newborns were accelerated in hyperthyroid group while these maturations were delayed partially in hypothyroid ones during the examined periods. These alterations, on both treated groups, were age and dose dependent. Thus, further studies need to be done to emphasize this concept. Published by Elsevier Ltd.

A Chemically Modified Curcumin (CMC 2.24) Inhibits Nuclear Factor κB Activation and Inflammatory Bone Loss in Murine Models of LPS-Induced Experimental Periodontitis and Diabetes-Associated Natural Periodontitis.

Science.gov (United States)

Elburki, Muna S; Rossa, Carlos; Guimarães-Stabili, Morgana R; Lee, Hsi-Ming; Curylofo-Zotti, Fabiana A; Johnson, Francis; Golub, Lorne M

2017-08-01

The purpose of this study was to assess the effect of a novel chemically modified curcumin (CMC 2.24) on NF-κB and MAPK signaling and inflammatory cytokine production in two experimental models of periodontal disease in rats. Experimental model I: Periodontitis was induced by repeated injections of LPS into the gingiva (3×/week, 3 weeks); control rats received vehicle injections. CMC 2.24, or the vehicle, was administered by daily oral gavage for 4 weeks. Experimental model II: Diabetes was induced in adult male rats by streptozotocin injection; periodontal breakdown then results as a complication of uncontrolled hyperglycemia. Non-diabetic rats served as controls. CMC 2.24, or the vehicle, was administered by oral gavage daily for 3 weeks to the diabetics. Hemimaxillae and gingival tissues were harvested, and bone loss was assessed radiographically. Gingival tissues were pooled according to the experimental conditions and processed for the analysis of matrix metalloproteinases (MMPs) and bone-resorptive cytokines. Activation of p38 MAPK and NF-κB signaling pathways was assessed by western blot. Both LPS and diabetes induced an inflammatory process in the gingival tissues associated with excessive alveolar bone resorption and increased activation of p65 (NF-κB) and p38 MAPK. In both models, the administration of CMC 2.24 produced a marked reduction of inflammatory cytokines and MMPs in the gingival tissues, decreased bone loss, and decreased activation of p65 (NF-κB) and p38 MAPK. Inhibition of these cell signaling pathways by this novel tri-ketonic curcuminoid (natural curcumin is di-ketonic) may play a role in its therapeutic efficacy in locally and systemically associated periodontitis.

An experimental investigation of proton-induced phenomena in krypton

International Nuclear Information System (INIS)

Mulders, J.J.L.

1985-01-01

In this thesis proton-induced phenomena in krypton gas are described. The considered reactions of protons on krypton are both nuclear and atomic. The nuclear conversion processes mainly result in the production of several Rb radioisotopes, such as 81 Rb that is used in 81 Rb-sup(81m)Kr generator systems for medical diagnostics. The irradiation of krypton gas (natural composition) with protons of about 26 MeV can be used for the routine production of 81 Rb from the direct production reaction 82 Kr(p,2n) 81 Rb and from the indirect reaction 82 Kr(p,2n)sup(81m)Rb → 81 Rb. To determine the scattering of protons in krypton gas targets a quantitative autoradiographic technique was developed. Proton profiles have been determined from the proton-induced activity distribution on a copper foil. For the on-line detection of produced Rb radioisotopes several optical detection techniques were investigated. (Auth.)

Functional Toll-like receptor 4 expressed in lactotrophs mediates LPS-induced proliferation in experimental pituitary hyperplasia

International Nuclear Information System (INIS)

Sabatino, María Eugenia; Sosa, Liliana del Valle; Petiti, Juan Pablo; Mukdsi, Jorge Humberto; Mascanfroni, Iván Darío; Pellizas, Claudia Gabriela; Gutiérrez, Silvina; Torres, Alicia Inés; De Paul, Ana Lucía

2013-01-01

Toll like receptor 4 (TLR4) has been characterized for its ability to recognize bacterial endotoxin lipopolysaccharide (LPS). Considering that infections or inflammatory processes might contribute to the progression of pituitary tumors, we analyzed the TLR4 functional role by evaluating the LPS effect on lactotroph proliferation in primary cultures from experimental pituitary tumors, and examined the involvement of PI3K-Akt and NF-κB activation in this effect. In addition, the role of 17β-estradiol as a possible modulator of LPS-induced PRL cell proliferation was further investigated. In estrogen-induced hyperplasic pituitaries, LPS triggered lactotroph cell proliferation. However, endotoxin failed to increase the number of lactotrophs taking up BrdU in normal pituitaries. Moreover, incubation with anti-TLR4 antibody significantly reduced LPS-induced lactotroph proliferation, suggesting a functional role of this receptor. As a sign of TLR4 activation, an LPS challenge increased IL-6 release in normal and tumoral cells. By flow cytometry, TLR4 baseline expression was revealed at the plasma membrane of tumoral lactotrophs, without changes noted in the percentage of double PRL/TLR4 positive cells after LPS stimulus. Increases in TLR4 intracellular expression were detected as well as rises in CD14, p-Akt and NF-κB after an LPS challenge, as assessed by western blotting. The TLR4/PRL and PRL/NF-κB co-localization was also corroborated by immunofluorescence and the involvement of PI3K/Akt signaling in lactotroph proliferation and IL-6 release was revealed through the PI3K inhibitor Ly-294002. In addition, 17β-estradiol attenuated the LPS-evoked increase in tumoral lactotroph proliferation and IL-6 release. Collectively these results demonstrate the presence of functional TLR4 in lactotrophs from estrogen-induced hyperplasic pituitaries, which responded to the proliferative stimulation and IL-6 release induced by LPS through TLR4/CD14, with a contribution of the PI3K

Functional Toll-like receptor 4 expressed in lactotrophs mediates LPS-induced proliferation in experimental pituitary hyperplasia

Energy Technology Data Exchange (ETDEWEB)

Sabatino, María Eugenia; Sosa, Liliana del Valle; Petiti, Juan Pablo; Mukdsi, Jorge Humberto [Centro de Microscopía Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Av. Enrique Barros y Enfermera Gordillo, Ciudad Universitaria, CP 5000, Córdoba (Argentina); Mascanfroni, Iván Darío; Pellizas, Claudia Gabriela [Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Av. Haya de la Torre y Medina Allende, Ciudad Universitaria, CP 5000, Córdoba (Argentina); Gutiérrez, Silvina; Torres, Alicia Inés [Centro de Microscopía Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Av. Enrique Barros y Enfermera Gordillo, Ciudad Universitaria, CP 5000, Córdoba (Argentina); De Paul, Ana Lucía, E-mail: adepaul@cmefcm.uncor.edu [Centro de Microscopía Electrónica, Instituto de Investigaciones en Ciencias de la Salud (INICSA-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Av. Enrique Barros y Enfermera Gordillo, Ciudad Universitaria, CP 5000, Córdoba (Argentina)

2013-11-15

Toll like receptor 4 (TLR4) has been characterized for its ability to recognize bacterial endotoxin lipopolysaccharide (LPS). Considering that infections or inflammatory processes might contribute to the progression of pituitary tumors, we analyzed the TLR4 functional role by evaluating the LPS effect on lactotroph proliferation in primary cultures from experimental pituitary tumors, and examined the involvement of PI3K-Akt and NF-κB activation in this effect. In addition, the role of 17β-estradiol as a possible modulator of LPS-induced PRL cell proliferation was further investigated. In estrogen-induced hyperplasic pituitaries, LPS triggered lactotroph cell proliferation. However, endotoxin failed to increase the number of lactotrophs taking up BrdU in normal pituitaries. Moreover, incubation with anti-TLR4 antibody significantly reduced LPS-induced lactotroph proliferation, suggesting a functional role of this receptor. As a sign of TLR4 activation, an LPS challenge increased IL-6 release in normal and tumoral cells. By flow cytometry, TLR4 baseline expression was revealed at the plasma membrane of tumoral lactotrophs, without changes noted in the percentage of double PRL/TLR4 positive cells after LPS stimulus. Increases in TLR4 intracellular expression were detected as well as rises in CD14, p-Akt and NF-κB after an LPS challenge, as assessed by western blotting. The TLR4/PRL and PRL/NF-κB co-localization was also corroborated by immunofluorescence and the involvement of PI3K/Akt signaling in lactotroph proliferation and IL-6 release was revealed through the PI3K inhibitor Ly-294002. In addition, 17β-estradiol attenuated the LPS-evoked increase in tumoral lactotroph proliferation and IL-6 release. Collectively these results demonstrate the presence of functional TLR4 in lactotrophs from estrogen-induced hyperplasic pituitaries, which responded to the proliferative stimulation and IL-6 release induced by LPS through TLR4/CD14, with a contribution of the PI3K

An Experimental Study of Roughness-Induced Instabilities in a Supersonic Boundary Layer

Science.gov (United States)

Kegerise, Michael A.; King, Rudolph A.; Choudhari, Meelan; Li, Fei; Norris, Andrew

2014-01-01

Progress on an experimental study of laminar-to-turbulent transition induced by an isolated roughness element in a supersonic laminar boundary layer is reported in this paper. Here, the primary focus is on the effects of roughness planform shape on the instability and transition characteristics. Four different roughness planform shapes were considered (a diamond, a circle, a right triangle, and a 45 degree fence) and the height and width of each one was held fixed so that a consistent frontal area was presented to the oncoming boundary layer. The nominal roughness Reynolds number was 462 and the ratio of the roughness height to the boundary layer thickness was 0.48. Detailed flow- field surveys in the wake of each geometry were performed via hot-wire anemometry. High- and low-speed streaks were observed in the wake of each roughness geometry, and the modified mean flow associated with these streak structures was found to support a single dominant convective instability mode. For the symmetric planform shapes - the diamond and circular planforms - the instability characteristics (mode shapes, growth rates, and frequencies) were found to be similar. For the asymmetric planform shapes - the right-triangle and 45 degree fence planforms - the mode shapes were asymmetrically distributed about the roughness-wake centerline. The instability growth rates for the asymmetric planforms were lower than those for the symmetric planforms and therefore, transition onset was delayed relative to the symmetric planforms.

Carvacrol attenuates N-nitrosodiethylamine induced liver injury in experimental Wistar rats

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Balan Rajan

2015-06-01

Full Text Available Carvacrol is a main constituent in the essential oils of countless aromatic plants including Origanum Vulgare and Thymus vulgari, which has been assessed for substantial pharmacological properties. In recent years, notable research has been embarked on to establish the biological actions of Carvacrol for its promising use in clinical applications. The present study is an attempt to reveal the protective role of Carvacrol against N-Nitrosodiethylamine (DEN induced hepatic injury in male Wistar albino rats. DEN is an egregious toxin, present in numerous environmental factors, which enhances chemical driven liver damage by inducing oxidative stress and cellular injury. Administration of DEN (200 mg/kg bodyweight, I.P to rats results in elevated marker enzymes (in both serum and tissue. Carvacrol (15 mg/kg body weight suppressed the elevation of marker enzymes (in both serum and tissue and augmented the antioxidants levels. The hoisted activities of Phase I enzymes and inferior activities of Phase II enzymes were observed in DEN-administered animals, whereas Carvacrol treated animals showed improved near normal activity. Histological observations also support the protective role of Carvacrol against DEN induced liver damage. Final outcome from our findings intimate that Carvacrol might be beneficial in attenuating toxin induced liver damage.

Collagen V-induced nasal tolerance downregulates pulmonary collagen mRNA gene and TGF-beta expression in experimental systemic sclerosis

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Parra Edwin R

2010-01-01

Full Text Available Abstract Background The purpose of this study was to evaluate collagen deposition, mRNA collagen synthesis and TGF-beta expression in the lung tissue in an experimental model of scleroderma after collagen V-induced nasal tolerance. Methods Female New Zealand rabbits (N = 12 were immunized with 1 mg/ml of collagen V in Freund's adjuvant (IM. After 150 days, six immunized animals were tolerated by nasal administration of collagen V (25 μg/day (IM-TOL daily for 60 days. The collagen content was determined by morphometry, and mRNA expressions of types I, III and V collagen were determined by Real-time PCR. The TGF-beta expression was evaluated by immunostaining and quantified by point counting methods. To statistic analysis ANOVA with Bonferroni test were employed for multiple comparison when appropriate and the level of significance was determined to be p Results IM-TOL, when compared to IM, showed significant reduction in total collagen content around the vessels (0.371 ± 0.118 vs. 0.874 ± 0.282, p p p = 0.026. The lung tissue of IM-TOL, when compared to IM, showed decreased immunostaining of types I, III and V collagen, reduced mRNA expression of types I (0.10 ± 0.07 vs. 1.0 ± 0.528, p = 0.002 and V (1.12 ± 0.42 vs. 4.74 ± 2.25, p = 0.009 collagen, in addition to decreased TGF-beta expression (p Conclusions Collagen V-induced nasal tolerance in the experimental model of SSc regulated the pulmonary remodeling process, inhibiting collagen deposition and collagen I and V mRNA synthesis. Additionally, it decreased TGF-beta expression, suggesting a promising therapeutic option for scleroderma treatment.

Experimental determination of the temperature range of AlO molecular emission in laser-induced aluminum plasma in air

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Bai, Xueshi; Motto-Ros, Vincent [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon Villeurbanne (France); Lei, Wenqi [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon Villeurbanne (France); State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China); Zheng, Lijuan [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China); Yu, Jin, E-mail: jin.yu@univ-lyon1.fr [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon Villeurbanne (France); Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astrophysics, Shanghai Jiao Tong University, Shanghai 200240 (China)

2014-09-01

Measurements with laser-induced breakdown spectroscopy (LIBS) usually take place in the atmospheric air. For quantitative analysis of metallic elements, oxidation may represent an important issue which can significantly modify the stoichiometry of the plasma. Molecule formation in plasma should be therefore studied and taken into account in the LIBS practice. In this work, we experimentally investigated the temporal evolution and transformation of the plasma induced on an aluminum target by a nanosecond infrared (1064 nm) laser in the atmospheric air, in terms of its temperatures over a large interval of time from hundreds of nanoseconds to tens of microseconds. Such evolution was then correlated to the temporal evolution of the emission intensity from AlO molecules in the ablation plume. In particular, for a given ablation laser pulse energy, the appearance of the molecular emission while the plume cools down allows determining a minimal delay, τ{sub min}, which corresponds to a maximal value of the temperature, T{sub max}, below which the molecular emission begins to be clearly observed and to grow as a function of the delay. Such delay or such temperature indicates the longest delay or the lowest temperature for laser-induced plasma to be suitable for a correct analysis of metallic elements without significant influence of the alternation of the stoichiometry by oxidation. In our experiment, the values of τ{sub min} and T{sub max} have been determined for a range of ablation laser pulse energies from 5 mJ to 50 mJ. These values lie respectively in the range of 3 to 15 μs for τ{sub min}, and 4500 K to 6600 K in terms of the molecule temperature for T{sub max}. Beyond the practical interest for LIBS, our results provide also insights to the kinetics of the AlO molecule formation in laser-induced plasma. - Highlights: • Determination of the temperatures in laser-induced plasma up to tens of microseconds • Determination of the molecule temperature by fitting

Experimental spinal cord trauma: a review of mechanically induced spinal cord injury in rat models.

Science.gov (United States)

Abdullahi, Dauda; Annuar, Azlina Ahmad; Mohamad, Masro; Aziz, Izzuddin; Sanusi, Junedah

2017-01-01

It has been shown that animal spinal cord compression (using methods such as clips, balloons, spinal cord strapping, or calibrated forceps) mimics the persistent spinal canal occlusion that is common in human spinal cord injury (SCI). These methods can be used to investigate the effects of compression or to know the optimal timing of decompression (as duration of compression can affect the outcome of pathology) in acute SCI. Compression models involve prolonged cord compression and are distinct from contusion models, which apply only transient force to inflict an acute injury to the spinal cord. While the use of forceps to compress the spinal cord is a common choice due to it being inexpensive, it has not been critically assessed against the other methods to determine whether it is the best method to use. To date, there is no available review specifically focused on the current compression methods of inducing SCI in rats; thus, we performed a systematic and comprehensive publication search to identify studies on experimental spinalization in rat models, and this review discusses the advantages and limitations of each method.

Immunization with Recombinantly Expressed LRP4 Induces Experimental Autoimmune Myasthenia Gravis in C57BL/6 Mice.

Science.gov (United States)

Ulusoy, Canan; Çavuş, Filiz; Yılmaz, Vuslat; Tüzün, Erdem

2017-07-01

Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction (NMJ), characterized with muscle weakness. While MG develops due to acetylcholine receptor (AChR) antibodies in most patients, antibodies to muscle-specific receptor tyrosine kinase (MuSK) or low-density lipoprotein receptor-related protein 4 (LRP4) may also be identified. Experimental autoimmune myasthenia gravis (EAMG) has been previously induced by both LRP4 immunization and passive transfer of LRP4 antibodies. Our aim was to confirm previous results and to test the pathogenic effects of LRP4 immunization in a commonly used mouse strain C57BL/6 (B6) using a recombinantly expressed human LRP4 protein. B6 mice were immunized with human LRP4 in CFA, Torpedo Californica AChR in CFA or only CFA. Clinical and pathogenic aspects of EAMG were compared among groups. LRP4- and AChR-immunized mice showed comparable EAMG clinical severity. LRP4-immunized mice displayed serum antibodies to LRP4 and NMJ IgG and complement factor C3 deposits. IgG2 was the dominant anti-LRP4 isotype. Cultured lymph node cells of LRP4- and AChR-immunized mice gave identical pro-inflammatory cytokine (IL-6, IFN-γ and IL-17) responses to LRP4 and AChR stimulation, respectively. Our results confirm the EAMG-inducing action of LRP4 immunization and identify B6 as a LRP4-EAMG-susceptible mouse strain. Demonstration of complement fixing anti-LRP4 antibodies in sera and complement/IgG deposits at the NMJ of LRP4-immunized mice indicates complement activation as a putative pathogenic mechanism. We have thus developed a practical LRP4-induced EAMG model using a non-conformational protein and a widely available mouse strain for future investigation of LRP4-related MG.

Preventive effects of p-coumaric acid on cardiac hypertrophy and alterations in electrocardiogram, lipids, and lipoproteins in experimentally induced myocardial infarcted rats.

Science.gov (United States)

Roy, Abhro Jyoti; Stanely Mainzen Prince, P

2013-10-01

The present study evaluated the preventive effects of p-coumaric acid on cardiac hypertrophy and alterations in electrocardiogram, lipids, and lipoproteins in experimentally induced myocardial infarcted rats. Rats were pretreated with p-coumaric acid (8 mg/kg body weight) daily for a period of 7 days and then injected with isoproterenol (100mg/kg body weight) on 8th and 9th day to induce myocardial infarction. Myocardial infarction induced by isoproterenol was indicated by increased level of cardiac sensitive marker and elevated ST-segments in the electrocardiogram. Also, the levels/concentrations of serum and heart cholesterol, triglycerides and free fatty acids were increased in myocardial infarcted rats. Isoproterenol also increased the levels of serum low density and very low density lipoprotein cholesterol and decreased the levels of high density lipoprotein cholesterol. It also enhanced the activity of liver 3-hydroxy-3 methyl glutaryl-Coenzyme-A reductase. p-Coumaric acid pretreatment revealed preventive effects on all the biochemical parameters and electrocardiogram studied in myocardial infarcted rats. The in vitro study confirmed the free radical scavenging property of p-coumaric acid. Thus, p-coumaric acid prevented cardiac hypertrophy and alterations in lipids, lipoproteins, and electrocardiogram, by virtue of its antihypertrophic, antilipidemic, and free radical scavenging effects in isoproterenol induced myocardial infarcted rats. Copyright © 2013 Elsevier Ltd. All rights reserved.

Inertial waves in a spherical shell induced by librations of the inner sphere: experimental and numerical results

Energy Technology Data Exchange (ETDEWEB)

Koch, S; Harlander, U; Egbers, C [Department of Aerodynamics and Fluid Mechanics, Brandenburg University of Technology Cottbus, Siemens-Halske-Ring 14, D-03046 Cottbus (Germany); Hollerbach, R, E-mail: uwe.harlander@tu-cottbus.de [Institute of Geophysics, ETH Zuerich, Sonneggstrasse 5, CH-8092 Zurich (Switzerland)

2013-06-15

We begin with an experimental investigation of the flow induced in a rotating spherical shell. The shell globally rotates with angular velocity {Omega}. A further periodic oscillation with angular velocity 0 Less-Than-Or-Slanted-Equal-To {omega} Less-Than-Or-Slanted-Equal-To 2{Omega}, a so-called longitudinal libration, is added on the inner sphere's rotation. The primary response is inertial waves spawned at the critical latitudes on the inner sphere, and propagating throughout the shell along inclined characteristics. For sufficiently large libration amplitudes, the higher harmonics also become important. Those harmonics whose frequencies are still less than 2{Omega} behave as inertial waves themselves, propagating along their own characteristics. The steady component of the flow consists of a prograde zonal jet on the cylinder tangent to the inner sphere and parallel to the axis of rotation, and increases with decreasing Ekman number. The jet becomes unstable for larger forcing amplitudes as can be deduced from the preliminary particle image velocimetry observations. Finally, a wave attractor is experimentally detected in the spherical shell as the pattern of largest variance. These findings are reproduced in a two-dimensional numerical investigation of the flow, and certain aspects can be studied numerically in greater detail. One aspect is the scaling of the width of the inertial shear layers and the width of the steady jet. Another is the partitioning of the kinetic energy between the forced wave, its harmonics and the mean flow. Finally, the numerical simulations allow for an investigation of instabilities, too local to be found experimentally. For strong libration amplitudes, the boundary layer on the inner sphere becomes unstable, triggering localized Goertler vortices during the prograde phase of the forcing. This instability is important for the transition to turbulence of the spherical shell flow. (paper)

An improved method to experimentally determine temperature and pressure behind laser-induced shock waves at low Mach numbers

International Nuclear Information System (INIS)

Hendijanifard, Mohammad; Willis, David A

2011-01-01

Laser-matter interactions are frequently studied by measuring the propagation of shock waves caused by the rapid laser-induced material removal. An improved method for calculating the thermo-fluid parameters behind shock waves is introduced in this work. Shock waves in ambient air, induced by pulsed Nd : YAG laser ablation of aluminium films, are measured using a shadowgraph apparatus. Normal shock solutions are applied to experimental data for shock wave positions and used to calculate pressure, temperature, and velocity behind the shock wave. Non-dimensionalizing the pressure and temperature with respect to the ambient values, the dimensionless pressure and temperature are estimated to be as high as 90 and 16, respectively, at a time of 10 ns after the ablation pulse for a laser fluence of F = 14.5 J cm -2 . The results of the normal shock solution and the Taylor-Sedov similarity solution are compared to show that the Taylor-Sedov solution under-predicts pressure when the Mach number of the shock wave is small. At a fluence of 3.1 J cm -2 , the shock wave Mach number is less than 3, and the Taylor-Sedov solution under-predicts the non-dimensional pressure by as much as 45%.

Amelioration of experimental autoimmune encephalomyelitis in C57BL/6 mice by photobiomodulation induced by 670 nm light.

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Kamaldeen A Muili

Full Text Available The approved immunomodulatory agents for the treatment of multiple sclerosis (MS are only partially effective. It is thought that the combination of immunomodulatory and neuroprotective strategies is necessary to prevent or reverse disease progression. Irradiation with far red/near infrared light, termed photobiomodulation, is a therapeutic approach for inflammatory and neurodegenerative diseases. Data suggests that near-infrared light functions through neuroprotective and anti-inflammatory mechanisms. We sought to investigate the clinical effect of photobiomodulation in the Experimental Autoimmune Encephalomyelitis (EAE model of multiple sclerosis.The clinical effect of photobiomodulation induced by 670 nm light was investigated in the C57BL/6 mouse model of EAE. Disease was induced with myelin oligodendrocyte glycoprotein (MOG according to standard laboratory protocol. Mice received 670 nm light or no light treatment (sham administered as suppression and treatment protocols. 670 nm light reduced disease severity with both protocols compared to sham treated mice. Disease amelioration was associated with down-regulation of proinflammatory cytokines (interferon-γ, tumor necrosis factor-α and up-regulation of anti-inflammatory cytokines (IL-4, IL-10 in vitro and in vivo.These studies document the therapeutic potential of photobiomodulation with 670 nm light in the EAE model, in part through modulation of the immune response.

Hexagonal boron nitride and graphene in-plane heterostructures: An experimentally feasible approach to charge-induced switchable CO{sub 2} capture

Energy Technology Data Exchange (ETDEWEB)

Tan, Xin; Tahini, Hassan A.; Smith, Sean C., E-mail: sean.smith@unsw.edu.au

2016-10-20

Hexagonal boron nitride (h-BN) has been proposed as a sorbent material for charge-induced switchable CO{sub 2} capture. However, h-BN is a wide-gap semiconductor, hindering injection of the requisite charge. Here, we employ first-principle calculations to support the proposal that in-plane h-BN/graphene (P-BN/G) heterostructures, consisting of alternating strips of h-BN and graphene, may provide an experimentally feasible material platform for voltage-induced charging of h-BN strips to realize switchable CO{sub 2} capture. Our results show that a significant amount of injected negative charges are distributed onto h-BN strips of P-BN/G, such that CO{sub 2} capture/release can be simply controlled by switching on/off the charge states of P-BN/G system. At saturation CO{sub 2} capture coverage, the negatively charged P-BN/G heterostructures achieve CO{sub 2} capture capacities up to 2.27 × 10{sup 14} cm{sup −2}, which is twice that which can be achieved on stacked h-BN/graphene (S-BN/G) nanosheets.

Costs and benefits of experimentally induced changes in the allocation of growth versus immune function under differential exposure to ectoparasites.

Directory of Open Access Journals (Sweden)

Natalia Pitala

2010-05-01

Full Text Available Ecological immunology has focused on the costs of investment in immunocompetence. However, understanding optimal resource allocation to immune defence requires also identification of its benefits, which are likely to occur only when parasites are abundant.We manipulated the abundance of parasitic hen fleas in blue tit (Cyanistes caeruleus nests, and supplemented their hosts, the nestlings, with methionine (a sulphur amino acid enhancing cell-mediated immunity during day 3-6. We found a significant interaction between these two experimental factors on the development of immune defences and growth rates. Only in parasitized nests did methionine supplementation boost immune (PHA response, and did nestling with experimentally increased immunocompetence show a relatively faster growth rate than control nestlings between days 6-9. Hence, the allocation of resources into immune defence and its growth-benefits are apparent only in presence of parasites. The main cost of methionine-induced increased allocation to the immune system was an increase in mortality, independently of ectoparasites. Nestlings in all treatments compensated initial growth reduction and all reached equal body size at day 16 (just prior to fledging, indicating a lack of long-term benefits. In addition, methionine treatment tended (P = 0.09 to lower circulating plasma immunoglobulin levels, possibly indicating a trade-off between the cell-mediated and humoral components of the immune system.We found no strong benefits of an increased investment in immunocompetence in a parasite-rich environment. Any deviation from the growth trajectory (due to changes in allocation induced by methionine is largely detrimental for survival. Hence, while costs are apparent identifying the benefits of investment in immunocompetence during ontogeny is challenging.

Anti-fibrotic effects of Cuscuta chinensis with in vitro hepatic stellate cells and a thioacetamide-induced experimental rat model.

Science.gov (United States)

Kim, Jin Seoub; Koppula, Sushruta; Yum, Mun Jeong; Shin, Gwang Mo; Chae, Yun Jin; Hong, Seok Min; Lee, Jae Dong; Song, MinDong

2017-12-01

Cuscuta chinensis Lam. (Convolvulaceae) has been used as a traditional herbal remedy for treating liver and kidney disorders. Anti-fibrotic effects of C. chinensis extract (CCE) in cellular and experimental animal models were investigated. HSC-T6 cell viability, cell cycle and apoptosis were analysed using MTT assay, flow cytometry and Annexin V-FITC/PI staining techniques. Thioacetamide (TAA)-induced fibrosis model was established using Sprague Dawley rats (n = 10). Control, TAA, CCE 10 (TAA with CCE 10 mg/kg), CCE 100 (TAA with CCE 100 mg/kg) and silymarin (TAA with silymarin 50 mg/kg). Fibrosis was induced by TAA (200 mg/kg, i.p.) twice per week for 13 weeks. CCE and silymarin were administered orally two times per week from the 7th to 13th week. Fibrotic related gene expression (α-SMA, Col1α1 and TGF-β1) was measured by RT-PCR. Serum biomarkers, glutathione (GSH) and hydroxyproline were estimated by spectrophotometer using commercial kits. CCE (0.05 and 0.1 mg/mL) and silymarin (0.05 mg/mL) treatment significantly (p < 0.01 and p < 0.001) induced apoptosis (11.56%, 17.52% for CCE; 16.50% for silymarin, respectively) in activated HSC-T6 cells, compared with control group (7.26%). Further, rat primary HSCs showed changes in morphology with CCE 0.1 mg/mL treatment. In in vivo studies, CCE (10 and 100 mg/kg) treatment ameliorated the TAA-induced altered levels of serum biomarkers, fibrotic related gene expression, GSH, hydroxyproline significantly (p < 0.05-0.001) and rescued the histopathological changes. CCE can be developed as a potential agent in the treatment of hepatofibrosis.

SIRT3 Expression Decreases with Reactive Oxygen Species Generation in Rat Cortical Neurons during Early Brain Injury Induced by Experimental Subarachnoid Hemorrhage

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Wei Huang

2016-01-01

Full Text Available Sirtuin3 (SIRT3 is an important protein deacetylase which predominantly presents in mitochondria and exhibits broad bioactivities including regulating energy metabolism and counteracting inflammatory effect. Since inflammatory cascade was proved to be critical for pathological damage following subarachnoid hemorrhage (SAH, we investigated the overall expression and cell-specific distribution of SIRT3 in the cerebral cortex of Sprague-Dawley rats with experimental SAH induced by internal carotid perforation. Results suggested that SIRT3 was expressed abundantly in neurons and endothelia but rarely in gliocytes in normal cerebral cortex. After experimental SAH, mRNA and protein expressions of SIRT3 decreased significantly as early as 8 hours and dropped to the minimum value at 24 h after SAH. By contrast, SOD2 expression increased slowly as early as 12 hours after experimental SAH, rose up sharply at the following 12 hours, and then was maintained at a higher level. In conclusion, attenuated SIRT3 expression in cortical neurons was associated closely with enhanced reactive oxygen species generation and cellular apoptosis, implying that SIRT3 might play an important neuroprotective role during early brain injury following SAH.

Combined static-dynamic MR urography for the simultaneous evaluation of morphology and function in urinary tract obstruction. II. Findings in experimentally induced ureteric stenosis

International Nuclear Information System (INIS)

Rohrschneider, W.K.; Becker, K.; Hoffend, J.; Clorius, J.H.; Darge, K.; Kooijman, H.; Troeger, J.

2000-01-01

Purpose. To assess the diagnostic value of combined static-dynamic MR urography (MRU) for the functional-morphological evaluation of experimentally induced urinary tract obstruction in the piglet. Materials and methods. In 20 piglets unilateral ureteric stenosis was created operatively. Post-surgery repeated comparative examinations were obtained with MRU, diuretic renal scintigraphy (DRS), excretory urography (EU) and ultrasound (US). MRU was performed as a combination study with a static 3D-IR-TSE sequence and a dynamic 2D-FFE sequence after Gd-DTPA with frusemide administration. Results. MRU allowed complete depiction of the prestenotic urinary tract and of the stenosis in all cases. In 43 comparative studies MRU was superior to EU in 36, EU to MRU in 2. When single kidney function was calculated with both MRU and DRS, results were highly correlated (r = 0.92). When urinary excretion was compared, significant agreement was achieved with concordant findings in 86 % and slightly discordant results in 12 %. Conclusions. Static-dynamic MR urography permits excellent depiction of experimentally induced urinary tract obstruction in piglets and reliable assessment of individual renal function and urinary excretion. Two advantages of the method stand out - it does not require radiation and it permits functional-morphological correlation. (orig.)

Inducibility of error-prone DNA repair in yeast

International Nuclear Information System (INIS)

Siede, W.; Eckardt, F.

1984-01-01

Whereas some experimental evidence suggests that mutagenesis in yeast after treatment with DNA-damaging agents involves inducible functions, a general-acting error-prone repair activity analogous to the SOS system of Escherichia coli has not yet been demonstrated. The current literature on the problem of inducibility of mutagenic repair in yeast is reviewed with emphasis on the differences in the experimental procedures applied. (orig.)

Aquaporin-1 and aquaporin-3 expressions in the temporo-mandibular joint condylar cartilage after an experimentally induced osteoarthritis.

Science.gov (United States)

Meng, Juan-hong; Ma, Xu-chen; Li, Zhi-min; Wu, Deng-cheng

2007-12-20

Over 70% of the total tissue weight in the cartilage matrix consists of water, and the early-stage osteoarthritic cartilage is characterized by swelling. Water transport in the cartilage matrix and across the membranes of chondrocytes may be important in normal and pathological conditions of cartilage. The purpose of this study was to identify aquaporin-1 (AQP1) and aquaporin-3 (AQP3) expressions in the mandibular condylar cartilage after experimentally induced osteoarthritis (OA) in rats. An experimental temporomandibular joint OA was induced by partial discectomy in rats. The pathological characteristics of the normal, early-stage, and late-stage osteoarthritic TMJ cartilages were verified by histological techniques. The AQP1 and AQP3 gene expressions in the normal and osteoarthritic cartilages were measured using quantitative real-time reverse-transcription PCR analysis. The cartilage sections were incubated in primary polyclonal antibodies to AQP3; immunofluorescent microscopy was used to examine the AQP3 expression shown by its protein level. The mRNA expression levels of AQP1 and AQP3, analyzed using quantitative PCR, revealed that AQP3 mRNA was highly up-regulated in the OA cartilage, which was considered significant. There was no notable difference in the expression of AQP1 mRNA between OA and normal controls. With the progressing of the OA, the localization of the AQP3 protein was quite different from that of the normal cartilage. Compared to the normal cartilage, the expressions of AQP3 protein were observed mainly in the proliferative zone and the upper mid-zone chondrocytes at the early-stage of OA, and were observed to appear frequently throughout the mid- and deep zone during the late-stage of OA. The high expression of AQP3 mRNA in the OA cartilage and the different localization of the AQP3 protein suggest that it may play a particular role in OA pathogenesis. Further study of AQP3 function may provide new insight into the understanding of the

Experimental investigation of ultraviolet laser induced plasma density and temperature evolution in air

International Nuclear Information System (INIS)

Thiyagarajan, Magesh; Scharer, John

2008-01-01

We present measurements and analysis of laser induced plasma neutral densities and temperatures in dry air by focusing 200 mJ, 10 MW high power, 193 nm ultraviolet ArF (argon fluoride) laser radiation to a 30 μm radius spot size. We examine these properties that result from multiphoton and collisional cascade processes for pressures ranging from 40 Torr to 5 atm. A laser shadowgraphy diagnostic technique is used to obtain the plasma electron temperature just after the shock front and this is compared with optical emission spectroscopic measurements of nitrogen rotational and vibrational temperatures. Two-color laser interferometry is employed to measure time resolved spatial electron and neutral density decay in initial local thermodynamic equilibrium (LTE) and non-LTE conditions. The radiating species and thermodynamic characteristics of the plasma are analyzed by means of optical emission spectroscopy (OES) supported by SPECAIR, a special OES program for air constituent plasmas. Core plasma rotational and vibrational temperatures are obtained from the emission spectra from the N 2 C-B(2+) transitions by matching the experimental spectrum results with the SPECAIR simulation results and the results are compared with the electron temperature just behind the shock wave. The plasma density decay measurements are compared with a simplified electron density decay model that illustrates the dominant three-and two-body recombination terms with good correlation

Spontaneous progression of ligature induced peri-implantitis at implants with different surface roughness: an experimental study in dogs

DEFF Research Database (Denmark)

Berglundh, T; Gotfredsen, K; Zitzmann, N U

2007-01-01

: The aim of the current experiment was to study the progression of peri-implantitis around implants with different surface roughness. MATERIAL AND METHODS: In five beagle dogs, three implants with either a sandblasted acid-etched surface (SLA) or a polished surface (P) were installed bilaterally......BACKGROUND: Peri-implantitis is associated with the presence of submarginal plaque, soft-tissue inflammation and advanced breakdown of the supporting bone. The progression of peri-implantitis following varying periods of continuing plaque accumulation has been studied in animal models. OBJECTIVE...... in the edentulous premolar regions. After 3 months on a plaque control regimen, experimental peri-implantitis was induced by ligature placement and plaque accumulation was allowed to progress until about 40% of the height of the supporting bone had been lost. After this 4-month period, ligatures were removed...

Experimental demonstration of squeezed-state quantum averaging

DEFF Research Database (Denmark)

Lassen, Mikael Østergaard; Madsen, Lars Skovgaard; Sabuncu, Metin

2010-01-01

We propose and experimentally demonstrate a universal quantum averaging process implementing the harmonic mean of quadrature variances. The averaged variances are prepared probabilistically by means of linear optical interference and measurement-induced conditioning. We verify that the implemented...

Activation of peripheral leukocytes in rat pregnancy and experimental preeclampsia

NARCIS (Netherlands)

Faas, MM; Schuiling, GA; Linton, EA; Sargent, IL; Redman, CWG

OBJECTIVE: The aim of this study was to search for activation markers of peripheral leukocytes in experimental preeclampsia in the rat. STUDY DESIGN: Experimental preeclampsia was induced in 14-day-pregnant rats by infusion of endotoxin (1.0 mu g/kg body weight). For comparison, rats with normal

Experimental study of induced staggered magnetic fields in dysprosium gallium garnet (DGG)

International Nuclear Information System (INIS)

Steiner, M.; Corliss, L.M.; Hastings, J.M.; Blume, M.; Giordano, N.; Wolf, W.P.

1979-01-01

Neutron diffraction techniques have been used to study induced staggered magnetic field effects in DGG. The application of a uniform magnetic field at temperatures much greater than the Neel temperature induces a significant amount of antiferromagnetic order. The temperature and field dependences of this effect are in good agreement with recent theoretical predicions

Experimental carcinogenesis induced by incorporated plutonium

International Nuclear Information System (INIS)

Oghiso, Yoichi

1999-01-01

The carcinogenic effects of an alpha-emitter, 239 Pu, were investigated by animal experiments as focused on both pulmonary tumors after inhalation exposures to insoluble oxide aerosols and tumor spectra induced by injection of soluble citrate. The life-span study using Wistar strain rats exposed to Pu dioxide aerosols has shown differential dose-related responses of malignancies and histopathological phenotypes of lung tumors, suggesting a threshold dose around 1.0 Gy of the lung dose. As abnormality of tumor-related genes could be supposed for the background of pulmonary carcinogenesis, the mutations of p53 tumor suppressor gene were examined by PCR-SSCP analysis using DNA fragments extracted from lung tumors. While mutations were detected in 23 cases (about 28%) among 82 lung tumors, their relations to either malignancies, histological phenotypes, dose, or oncogenesis are not yet to be elucidated. The life-span study using C3H strain mice injected with Pu citrate has shown contrast dose responses between osteosarcomas and lymphoid tumors around 10 Gy of the skeletal dose, and further indicated specific tumor spectra differed from low LET radiation exposures as shown by much more frequency of B cell type leukemic lymphomas and none of myeloid leukemias. (author)

Cellular Pathways of Hereditary Spastic Paraplegia*

OpenAIRE

Blackstone, Craig

2012-01-01

Human voluntary movement is controlled by the pyramidal motor system, a long CNS pathway comprising corticospinal and lower motor neurons. Hereditary spastic paraplegias (HSPs) are a large, genetically diverse group of inherited neurologic disorders characterized by a length-dependent distal axonopathy of the corticospinal tracts, resulting in lower limb spasticity and weakness. A range of studies are converging on alterations in the shaping of organelles, particularly the endoplasmic reticul...

Experimentally induced gestational androgen excess disrupts glucoregulation in rhesus monkey dams and their female offspring.

Science.gov (United States)

Abbott, David H; Bruns, Cristin R; Barnett, Deborah K; Dunaif, Andrea; Goodfriend, Theodore L; Dumesic, Daniel A; Tarantal, Alice F

2010-11-01

Discrete fetal androgen excess during early gestation in rhesus monkeys (Macaca mulatta) promotes endocrine antecedents of adult polycystic ovary syndrome (PCOS)-like traits in female offspring. Because developmental changes promoting such PCOS-like metabolic dysfunction remain unclear, the present study examined time-mated, gravid rhesus monkeys with female fetuses, of which nine gravid females received 15 mg of testosterone propionate (TP) subcutaneously daily from 40 to 80 days (first to second trimesters) of gestation [term, mean (range): 165 (155-175) days], whereas an additional six such females received oil vehicle injections over the same time interval. During gestation, ultrasonography quantified fetal growth measures and was used as an adjunct for fetal blood collections. At term, all fetuses were delivered by cesarean section for postnatal studies. Blood samples were collected from dams and infants for glucose, insulin, and total free fatty acid (FFA) determinations. TP injections transiently accelerated maternal weight gain in dams, very modestly increased head diameter of prenatally androgenized (PA) fetuses, and modestly increased weight gain in infancy compared with concurrent controls. Mild to moderate glucose intolerance, with increased area-under-the-curve circulating insulin values, occurred in TP-injected dams during an intravenous glucose tolerance test in the early second trimester. Moreover, reduced circulating FFA levels occurred in PA fetuses during a third trimester intravenous glucagon-tolbutamide challenge (140 days gestation), whereas excessive insulin sensitivity and increased insulin secretion relative to insulin sensitivity occurred in PA infants during an intravenous glucose-tolbutamide test at ∼1.5 mo postnatal age. Data from these studies suggest that experimentally induced fetal androgen excess may result in transient hyperglycemic episodes in the intrauterine environment that are sufficient to induce relative increases in

Experimental validation of the design method to prevent flow-induced vibration in high Reynolds-number

International Nuclear Information System (INIS)

Sakai, Takaaki; Yamaguchi, Akira; Morisita, Masaki; Iwata, Koji

1998-08-01

The incident of sodium leakage from a main pipe of the secondary heat transport system of Monju fast breeder reactor was caused by the failure of a thermometer well. 'Flow-induced vibration design guide for thermometer wells' (express as 'design guide') was proposed by PNC Working Group to prevent the same cause of the sodium leak incident in future. On this report, applicability of the 'design guide' was estimated to plant conditions in high Reynolds-number(approximately 3x10 5 ∼ 3x10 6 ) involving the supercritical region, by measured data on a vortex synchronized vibration and a turbulence induced vibration. Experiments were performed for cylindrical and taper shaped types of test pieces. As results, reduced velocity (Vr) at onsets of the inline synchronized vibration were evaluated to be grater than 1.0 in the range of experimental conditions. Fluctuating drag and lift coefficients, which were evaluated from power spectrum of turbulence for Vr < 1.0 condition, were 0.01 ∼ 0.05 for drag direction and 0.04 ∼ 0.13 for lift direction. The fluctuating drag and lift coefficients used in the 'design guide' were estimated to be conservative by comparison with these data. Correlation lengths for a cylinder and a taper shaped one in the high Reynolds-number region were estimated to be 1.6 times of the diameter(D) in the maximum case. The measured value of correlation length is enough smaller than the 'design guide' value of 3.0D. Displacement amplitudes of test pieces for Vr < 1.0 conditions were enough smaller (fives times) than calculated values based on the 'design guide'. Consequently, the applicability of the design guide' was confirmed in the range of experiments involving the super critical Reynolds-number region. (author)

Nyctanthes arbor-tristis Ameliorated FCA-Induced Experimental Arthritis: A Comparative Study among Different Extracts

Science.gov (United States)

Uroos, Maliha; Sattar, Shumaila; Umer, Nigarish; Sharif, Ahsan

2017-01-01

Nyctanthes arbor-tristis (NAT) is commonly used traditionally for the treatment of rheumatism and inflammatory diseases. Current study evaluates the antiarthritic potential of NAT using Freund's adjuvant-induced arthritic rat model. Treatments with methanolic, ethyl acetate, and n-hexane extracts were continued for consecutive 20 days. Macroscopic arthritic scoring and water displacement plethysmometry were used to evaluate arthritic development. Hematological and biochemical parameters were investigated and ankle joints were processed for histopathological evaluation. Qualitative phytochemical analysis and GC-MS analysis were conducted for identification of constituents. NAT extracts suppressed arthritic scoring, paw edema, infiltration of inflammatory cells, pannus formation, and bone erosion. The plant extracts ameliorated total leukocytes and platelet counts and nearly normalized red blood cells (RBC) counts and hemoglobin (Hb) content. The extracts were found safe in terms of hepatotoxicity and nephrotoxicity as determined by aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and urea levels. Comparative analysis showed that ethyl acetate extract produced the highest inhibition of paw edema. The major constituents found in ethyl acetate extract can be classified into three major classes, that is, terpenes, terpenoids, fatty acids, and iridoid glycosides. Current study showed that Nyctanthes arbor-tristis ameliorated experimental rheumatoid arthritis and ethyl acetate extract possessed the highest inhibitory activity. PMID:28676830

Hepatocellular hypoxia-induced vascular endothelial growth factor expression and angiogenesis in experimental biliary cirrhosis.

Science.gov (United States)

Rosmorduc, O; Wendum, D; Corpechot, C; Galy, B; Sebbagh, N; Raleigh, J; Housset, C; Poupon, R

1999-10-01

We tested the potential role of vascular endothelial growth factor (VEGF) and of fibroblast growth factor-2 (FGF-2) in the angiogenesis associated with experimental liver fibrogenesis induced by common bile duct ligation in Sprague-Dawley rats. In normal rats, VEGF and FGF-2 immunoreactivities were restricted to less than 3% of hepatocytes. One week after bile duct ligation, hypoxia was demonstrated by the immunodetection of pimonidazole adducts unevenly distributed throughout the lobule. After 2 weeks, hypoxia and VEGF expression were detected in >95% of hepatocytes and coexisted with an increase in periportal vascular endothelial cell proliferation, as ascertained by Ki67 immunolabeling. Subsequently, at 3 weeks the density of von Willebrand-labeled vascular section in fibrotic areas significantly increased. Semiquantitative reverse transcription polymerase chain reaction showed that VEGF(120) and VEGF(164) transcripts, that correspond to secreted isoforms, increased within 2 weeks, while VEGF(188) transcripts remained unchanged. FGF-2 mainly consisting of a 22-kd isoform, according to Western blot, was identified by immunohistochemistry in 49% and 100% of hepatocytes at 3 and 7 weeks, respectively. Our data provide evidence that in biliary-type liver fibrogenesis, angiogenesis is stimulated primarily by VEGF in response to hepatocellular hypoxia while FGF-2 likely contributes to the maintenance of angiogenesis at later stages.

Pulmonary emphysema induced by methylphenidate: experimental study.

Science.gov (United States)

Rapello, Gabriel Victor Guimarães; Antoniolli, Andréia; Pereira, Daniel Martins; Facco, Gilberto; Pêgo-Fernandes, Paulo Manuel; Pazetti, Rogério

2015-01-01

Methylphenidate is the most widely used drug for treating attention deficit hyperactivity disorder. However, it has important side effects, such as abdominal pain, insomnia, anorexia and loss of appetite, and also some cases of early severe emphysema after drug abuse have been reported. Our aim was to investigate the development of pulmonary emphysema in rats that were subjected to different doses of methylphenidate. Experimental study carried out at the laboratory of a public university. Eighteen male Wistar rats were divided into three groups: control (0.9% saline solution); MP 0.8 (methylphenidate, 0.8 mg/kg); MP 1.2 (methylphenidate, 1.2 mg/kg). After 90 days of daily gavage, the animals were sacrificed and lung tissue samples were prepared for analysis on the mean alveolar diameter (Lm). The Lm was greater in MP 0.8 (47.91 ± 3.13; P pulmonary emphysema.

Boron-implantation-induced crystalline-to-amorphous transition in nickel: An experimental assessment of the generalized Lindemann melting criterion

International Nuclear Information System (INIS)

Liu, P.C.; Okamoto, P.R.; Zaluzec, N.J.; Meshii, M.

1999-01-01

The generalized Lindemann melting hypothesis has recently been used to develop a unified thermodynamic criterion for melting applicable to both heat-induced melting and disorder-induced crystalline-to-amorphous (c-a) transformation. The hypothesis stipulates that the sum left-angle μ 2 right-angle Total of the static and dynamic root-mean-square (rms) atomic displacements is a constant fraction of the nearest-neighbor distance along the melting curve of a solid. To test this hypothesis, energy-filtered selected area electron-diffraction intensity measurements were used to determine the generalized Lindemann parameter δ=√ (left-angle μ 2 right-angle Total ) /d nn , in which d nn represents the nearest-neighbor distance, as a function of boron concentration during implantation of 50-keV ampersand hthinsp;B + into polycrystalline Ni at 77 K. The onset of amorphization was found to occur close to 10 at.ampersand hthinsp;% boron, which is in good agreement with the value predicted by T o curve calculated using the generalized Lindemann hypothesis. Moreover, the critical value of the generalized Lindemann parameter for amorphization, δ Critical =0.115±0.01, is within experimental error, identical to that for Ni just below its thermodynamic melting temperature of T=1728 ampersand hthinsp;K, hence providing a direct confirmation for the generalized Lindemann melting hypothesis. copyright 1999 The American Physical Society

Experimental and theoretical studies of bombardment induced surface morphology changes

International Nuclear Information System (INIS)

Carter, G.; Nobes, M.J.; Williams, J.S.

1980-01-01

In this review results of experimental and theoretical studies of solid surface morphology changes due to ion bombardment are discussed. An attempt is undertaken to classify the observed specific features of a structure, generated by ion bombardment [ru

Endogenous opioid antagonism in physiological experimental pain models

DEFF Research Database (Denmark)

Werner, Mads U; Pereira, Manuel P; Andersen, Lars Peter H

2015-01-01

hyperalgesia models (6 studies), 'pain' models (25 studies), summation models (2 studies), nociceptive reflex models (3 studies) and miscellaneous models (2 studies). A consistent reversal of analgesia by a MOR-antagonist was demonstrated in 10 of the 25 ITP-studies, including stress-induced analgesia and r...... ratings, threshold assessments and somatosensory evoked potentials (SSEP), did not appear consistent in 28 out of 32 'pain' model studies. In conclusion, only in 2 experimental human pain models, i.e., stress-induced analgesia and rTMS, administration of MOR-antagonist demonstrated a consistent effect......Opioid antagonists are pharmacological tools applied as an indirect measure to detect activation of the endogenous opioid system (EOS) in experimental pain models. The objective of this systematic review was to examine the effect of mu-opioid-receptor (MOR) antagonists in placebo-controlled, double...

Experimental evidence of infrared scintillation in crystals

CERN Document Server

Belogurov, S; Carugno, Giovanni; Conti, E; Iannuzzi, D; Meneguzzo, Anna Teresa

2000-01-01

We present experimental results on infrared emission induced by protons in some solid-state samples. Infrared scintillation occurs in many crystals, with different yield values and time-response behaviours. A rough measurement of the emission wavelength of CsI(Tl) is also reported.

Experimental Malaria in Pregnancy Induces Neurocognitive Injury in Uninfected Offspring via a C5a-C5a Receptor Dependent Pathway.

Directory of Open Access Journals (Sweden)

Chloë R McDonald

2015-09-01

Full Text Available The in utero environment profoundly impacts childhood neurodevelopment and behaviour. A substantial proportion of pregnancies in Africa are at risk of malaria in pregnancy (MIP however the impact of in utero exposure to MIP on fetal neurodevelopment is unknown. Complement activation, in particular C5a, may contribute to neuropathology and adverse outcomes during MIP. We used an experimental model of MIP and standardized neurocognitive testing, MRI, micro-CT and HPLC analysis of neurotransmitter levels, to test the hypothesis that in utero exposure to malaria alters neurodevelopment through a C5a-C5aR dependent pathway. We show that malaria-exposed offspring have persistent neurocognitive deficits in memory and affective-like behaviour compared to unexposed controls. These deficits were associated with reduced regional brain levels of major biogenic amines and BDNF that were rescued by disruption of C5a-C5aR signaling using genetic and functional approaches. Our results demonstrate that experimental MIP induces neurocognitive deficits in offspring and suggest novel targets for intervention.

Experimental and numerical investigations on flashing-induced instabilities in a single channel

Energy Technology Data Exchange (ETDEWEB)

Marcel, Christian P.; Rohde, M.; Van Der Hagen, T.H.J.J. [Department of Physics of Nuclear Reactors, Delft University of Technology (TUDelft), Delft, 2629 JB (Netherlands)

2009-11-15

During the start-up phase, natural circulation BWRs (NC-BWRs) need to be operated at low pressure conditions. Such conditions favor flashing-induced instabilities due to the large hydrostatic pressure drop induced by the tall chimney. Moreover, in novel NC-BWR designs the steam separation is performed in the steam separators which create large pressure drops at the chimney outlet, which effect on stability has not been investigated yet. In this work, flashing-induced oscillations occurring in a tall, bottom heated channel are numerically investigated by using a simple linear model with three regions and an accurate implementation for estimating the water properties. The model is used to investigate flashing-induced instabilities in a channel for different values of the core inlet friction value. The results are compared with experiments obtained by using the CIRCUS facility at the same conditions, showing a good agreement. In addition, the experiments on flashing-induced instabilities are presented in a novel manner allowing visualizing new details of the phenomenon numerical stability investigations on the effect of the friction distribution are also done. It is found that by increasing the total restriction in the channel the system is destabilized. In addition, the chimney outlet restriction has a stronger destabilizing effect than the core inlet restriction. A stable two-phase region is observed prior to the instabilities in the experiments and the numerical simulations which may help to pressurize the vessel of NC-BWRs and thus reducing the effects of flashing instabilities during start-up. (author)

Effect of Citrullus colocynthis hydro-alcoholic extract on hormonal and folliculogenesis process in estradiol valerate-induced PCOs rats model: An experimental study.

Science.gov (United States)

Barzegar, Mohammad Hossein; Khazali, Homayoun; Kalantar, Seyyed Mehdi; Khoradmehr, Arezoo

2017-10-01

Citrullus colocynthis (CCT) is used as the anti-diabetic and antioxidant agent. Polycystic ovarian syndrome (PCOS) is a reproductive disorder which level of gonadotropins and sexual hormones are imbalanced. We evaluated the effect of CCT hydro-alcoholic extract on hormonal and folliculogenesis process in estradiol valerate-induced PCOs rats' model. 40 female adult Wistar rats divided into five groups (n=8each: Group I (control) only injected by sesame oil as estradiol valerate solvent, group II (Sham) was orally received normal saline after estradiol valerate- induced polycystic ovarian syndrome (4 mg/rat estradiol valerate, intramuscularly), and three experimental groups, that after induction of PCOS within 60 days, received orally 50 mg/kg CCT extract (group III), 50mg/kg metformin (group IV), and CCT extract+ metformin (group V) for 20 days. The serum concentration level of luteinizing, testosterone and follicle stimulating hormones were measured using ELISA method and the serum concentration level of glucose were measured using the oxidative method (glucose meter). Histological study of ovary tissue carried out by hematoxylin-eosin staining. There was a significant reduction in luteinizing hormone and testosterone in III-V groups compared to Sham group, whereas follicle stimulating hormone in III-V groups was not significantly changed in comparison with Sham group. Histological investigations showed a significant increase in number of preantral and antral follicles and corpus luteum in the experimental groups compared to group II. Marked improvement in hormonal and histological symptoms of PCOS may be due to CCT effects hence, CCT can potentially be considered as an effective drug for treatment of PCOS.

Illusions and delusions: relating experimentally-induced false memories to anomalous experiences and ideas

Directory of Open Access Journals (Sweden)

Philip R Corlett

2009-11-01

Full Text Available The salience hypothesis of psychosis rests on a simple but profound observation that subtle alterations in the way that we perceive and experience stimuli have important consequences for how important these stimuli become for us, how much they draw our attention, how they embed themselves in our memory and, ultimately, how they shape our beliefs. We put forward the idea that a classical memory illusion – the Deese-Roediger-McDermott (DRM effect – offers a useful way of exploring processes related to such aberrant belief formation. The illusion occurs when, as a consequence of its relationship to previous stimuli, a stimulus is asserted to be remembered even when has not been previously presented. Such illusory familiarity is thought to be generated by the surprising fluency with which the stimulus is processed. In this respect, the illusion relates directly to the salience hypothesis and may share common cognitive underpinnings with aberrations of perception and attribution that are found in psychosis. In this paper, we explore the theoretical importance of this experimentally-induced illusion in relation to the salience model of psychosis. We present data showing that, in healthy volunteers, the illusion relates directly to self reported anomalies of experience and magical thinking. We discuss this finding in terms of the salience hypothesis and of a broader Bayesian framework of perception and cognition which emphasizes the salience both of predictable and unpredictable experiences..

Anti-atherosclerotic effect of Cynodon dactylon extract on experimentally induced hypercholesterolemia in rats.

Science.gov (United States)

Pashaie, Belal; Hobbenaghi, Rahim; Malekinejad, Hassan

2017-01-01

Cynodon dactylon (Bermuda grass) is a perennial plant traditionally used as an herbal medicine in many countries. In the present study, anti-atherosclerotic property of ethanolic extract of C. dactylon was investigated in the experimentally induced hypercholesterolemia in rats. In this study, 36 male Wistar rats were selected and allocated into six groups (n = 6). The control group received a normal diet, sham group received a high cholesterol diet (HCD; 1.50% cholesterol and 24.00% fat) and other groups received a HCD and ethanolic extract of C. dactylon at low (100 mg kg -1 ), moderate (200 mg kg -1 ) and maximum (400 mg kg -1 ) doses via gavages. The last group received atorvastatin (10 mg kg -1 ) through gavage with a HCD. The study period for all groups was six months. At the end of this period, parameters including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were assessed in the blood samples. Additionally, histopathological and immunohistochemical examinations on coronary and aorta arteries sections were performed. The results showed an increase in vessels wall thickness and proliferation of smooth muscle cells in the HCD group, while these pathological changes were not seen in C. dactylon -treated groups. Treatment of HCD animals with C. dactylon positively changed lipid profile by lowering of TC, TG and LDL-C. The results indicate that C. dactylon prevents from early atherosclerotic changes in the vessels wall.

Experimental Issues in Testing a Semiactive Technique to Control Earthquake Induced Vibration

Directory of Open Access Journals (Sweden)

Nicola Caterino

2014-01-01

Full Text Available This work focuses on the issues to deal with when approaching experimental testing of structures equipped with semiactive control (SA systems. It starts from practical experience authors gained in a recent wide campaign on a large scale steel frame structure provided with a control system based on magnetorheological dampers. The latter are special devices able to achieve a wide range of physical behaviours using low-power electrical currents. Experimental activities involving the use of controllable devices require special attention in solving specific aspects that characterize each of the three phases of the SA control loop: acquisition, processing, and command. Most of them are uncommon to any other type of structural testing. This paper emphasizes the importance of the experimental assessment of SA systems and shows how many problematic issues likely to happen in real applications are also present when testing these systems experimentally. This paper highlights several problematic aspects and illustrates how they can be addressed in order to achieve a more realistic evaluation of the effectiveness of SA control solutions. Undesired and unavoidable effects like delays and control malfunction are also remarked. A discussion on the way to reduce their incidence is also offered.

vaccination using profilin and NetB proteins in Montanide IMS adjuvant increases protective immunity against experimentally-induced necrotic enteritis

Directory of Open Access Journals (Sweden)

Hyun Soon Lillehoj

2017-10-01

Full Text Available Objective The effects of vaccinating 18-day-old chicken embryos with the combination of recombinant Eimeria profilin plus Clostridium perfringens (C. perfringens NetB proteins mixed in the Montanide IMS adjuvant on the chicken immune response to necrotic enteritis (NE were investigated using an Eimeria maxima (E. maxima/C. perfringens co-infection NE disease model that we previously developed. Methods Eighteen-day-old broiler embryos were injected with 100 μL of phosphate-buffered saline, profilin, profilin plus necrotic enteritis B-like (NetB, profilin plus NetB/Montanide adjuvant (IMS 106, and profilin plus Net-B/Montanide adjuvant (IMS 101. After post-hatch birds were challenged with our NE experimental disease model, body weights, intestinal lesions, serum antibody levels to NetB, and proinflammatory cytokine and chemokine mRNA levels in intestinal intraepithelial lymphocytes were measured. Results Chickens in ovo vaccinated with recombinant profilin plus NetB proteins/IMS106 and recombinant profilin plus NetB proteins/IMS101 showed significantly increased body weight gains and reduced gut damages compared with the profilin-only group, respectively. Greater antibody response to NetB toxin were observed in the profilin plus NetB/IMS 106, and profilin plus NetB/IMS 101 groups compared with the other three vaccine/adjuvant groups. Finally, diminished levels of transcripts encoding for proinflammatory cytokines such as lipopolysaccharide-induced tumor necrosis factor-α factor, tumor necrosis factor superfamily 15, and interleukin-8 were observed in the intestinal lymphocytes of chickens in ovo injected with profilin plus NetB toxin in combination with IMS 106, and profilin plus NetB toxin in combination with IMS 101 compared with profilin protein alone bird. Conclusion These results suggest that the Montanide IMS adjuvants potentiate host immunity to experimentally-induced avian NE when administered in ovo in conjunction with the profilin and

The mechanisms of the hadron-nucleus collision processes and of the hadron-nucleus collision induced nuclear reactions - in the light of experimental data

International Nuclear Information System (INIS)

Strugalski, Z.; Strugalska-Gola, E.

1997-01-01

The mechanisms of the hadron-nucleus collision processes and of the hadron-nucleus collision induced nuclear reactions are described - as experimentally based. The target nuclei are damaged definitely and locally in the collisions and the configurations of the nucleons in them became instable. The configuration must transit into stable stages of the nuclear transition reaction products. The difference between the initial internal energy of the unstable residual nucleus and the total final energy of the stable products of the nuclear transition reaction may be released in some cases

Filament-induced remote surface ablation for long range laser-induced breakdown spectroscopy operation

International Nuclear Information System (INIS)

Rohwetter, Ph.; Stelmaszczyk, K.; Woeste, L.; Ackermann, R.; Mejean, G.; Salmon, E.; Kasparian, J.; Yu, J.; Wolf, J.-P.

2005-01-01

We demonstrate laser induced ablation and plasma line emission from a metallic target at distances up to 180 m from the laser, using filaments (self-guided propagation structures ∼ 100 μm in diameter and ∼ 5 x 10 13 W/cm 2 in intensity) appearing as femtosecond and terawatt laser pulses propagating in air. The remarkable property of filaments to propagate over a long distance independently of the diffraction limit opens the frontier to long range operation of the laser-induced breakdown spectroscopy technique. We call this special configuration of remote laser-induced breakdown spectroscopy 'remote filament-induced breakdown spectroscopy'. Our results show main features of filament-induced ablation on the surface of a metallic sample and associated plasma emission. Our experimental data allow us to estimate requirements for the detection system needed for kilometer-range remote filament-induced breakdown spectroscopy experiment

Effects of subanesthetic doses of ketamine in cats with induced experimental endotoxemia

Directory of Open Access Journals (Sweden)

Felipe Hertzing Farias

2015-12-01

Full Text Available ABSTRACT. Farias F.H., Gehrcke M.I., Padilha V.S., Volpato J., Tochetto R., Comassetto F. & Oleskovicz N. [Effects of subanesthetic doses of ketamine in cats with induced experimental endotoxemia.] Efeitos da cetamina em doses subanestésicas em gatos submetidos à endotoxemia experimental. Revista Brasileira de Medicina Veterinária, 37(4:297-302, 2015. Programa de Pós-Graduação em Ciência Animal, Centro de Ciências Agroveterinárias, Universidade do Estado de Santa Catarina, Avenida Luís de Camões, 2090, Bairro Conta Dinheiro, Lages, SC 88520-000, Brasil. E-mail: noleskovicz@yahoo.com.br The clinical endotoxemia is difficult to diagnosis and treatment because of the involvement of multiple organs. This study aimed to evaluate the clinical effects of subanesthetic doses of ketamine, before or after the induction of endotoxemia in cats. Were used nine healthy cats, with 4.3±0.59 kg, autocontroles, placed into three groups: lipopolysaccharide (LPS, n=9 received a bolus of NaCl 0,9 % followed by a continuous infusion (CI of LPS for two hours and; bolus of NaCl 0,9 % followed by CI of LPS for two hours; ketamine/LPS (C/ LPS, n=9 received a bolus of ketamine followed by ketamine CI and LPS for two hours and, after, bolus of saline followed by CI of LPS for another two hours; LPS/ketamine (LPS/C, n=9 received bolus of saline followed by a CI LPS for two hours and then after bolus of ketamine followed by the same CI associated with LPS for two hours. The heart rate was higher for 5 to 120 minutes after initiation of the CI LPS in C/LPS and less than 150 to 240 minutes and from 600 to 720 minutes in LPS compared to the other groups. Five minutes after CI LPS initiation in C/LPS, 60 minutes in LPS/C and 90 minutes to 720 minutes in LPS, FC was higher than at baseline. The PAS was lower in all groups from 360 to 720 minutes compared to baseline. All treatments showed increased TR from 60 to 600 minutes compared to baseline. The levels of glucose

Muon-induced fission

International Nuclear Information System (INIS)

Polikanov, S.

1980-01-01

A review of recent experimental results on negative-muon-induced fission, both of 238 U and 232 Th, is given. Some conclusions drawn by the author are concerned with muonic atoms of fission fragments and muonic atoms of the shape isomer of 238 U. (author)

HIF-2α-induced chemokines stimulate motility of fibroblast-like synoviocytes and chondrocytes into the cartilage-pannus interface in experimental rheumatoid arthritis mouse models.

Science.gov (United States)

Huh, Yun Hyun; Lee, Gyuseok; Lee, Keun-Bae; Koh, Jeong-Tae; Chun, Jang-Soo; Ryu, Je-Hwang

2015-10-29

Pannus formation and resulting cartilage destruction during rheumatoid arthritis (RA) depends on the migration of synoviocytes to cartilage tissue. Here, we focused on the role of hypoxia-inducible factor (HIF)-2α-induced chemokines by chondrocytes in the regulation of fibroblast-like synoviocyte (FLS) migration into the cartilage-pannus interface and cartilage erosion. Collagen-induced arthritis (CIA), K/BxN serum transfer, and tumor necrosis factor-α transgenic mice were used as experimental RA models. Expression patterns of HIF-2α and chemokines were determined via immunostaining, Western blotting and RT-PCR. FLS motility was evaluated using transwell migration and invasion assays. The specific role of HIF-2α was determined via local deletion of HIF-2α in joint tissues or using conditional knockout (KO) mice. Cartilage destruction, synovitis and pannus formation were assessed via histological analysis. HIF-2α and various chemokines were markedly upregulated in degenerating cartilage and pannus of RA joints. HIF-2α induced chemokine expression by chondrocytes in both primary culture and cartilage tissue. HIF-2α -induced chemokines by chondrocytes regulated the migration and invasion of FLS. Local deletion of HIF-2α in joint tissues inhibited pannus formation adjacent to cartilage tissue and cartilage destruction caused by K/BxN serum transfer. Furthermore, conditional knockout of HIF-2α in cartilage blocked pannus formation in adjacent cartilage but not bone tissue, along with inhibition of cartilage erosion caused by K/BxN serum transfer. Our findings suggest that chemokines induced by IL-1β or HIF-2α in chondrocytes regulate pannus expansion by stimulating FLS migration and invasion, leading to cartilage erosion during RA pathogenesis.

Hereditary spastic paraplegias: membrane traffic and the motor pathway

OpenAIRE

Blackstone, Craig; O’Kane, Cahir J.; Reid, Evan

2011-01-01

Voluntary movement is a fundamental way in which animals respond to, and interact with, their environment. In mammals, the main CNS pathway controlling voluntary movement is the corticospinal tract, which encompasses connections between the cerebral motor cortex and the spinal cord. Hereditary spastic paraplegias (HSPs) are a group of genetic disorders that lead to a length-dependent, distal axonopathy of fibres of the corticospinal tract, causing lower limb spasticity and weakness. Recent wo...

Recent mouse and rat methods for the study of experimental oral candidiasis.

Science.gov (United States)

Costa, Anna C B P; Pereira, Cristiane A; Junqueira, Juliana C; Jorge, Antonio O C

2013-07-01

The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis.

Recent mouse and rat methods for the study of experimental oral candidiasis

Science.gov (United States)

Costa, Anna CBP; Pereira, Cristiane A; Junqueira, Juliana C; Jorge, Antonio OC

2013-01-01

The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis. PMID:23715031

Surgical manipulation compromises leukocyte mobilisation responses and inflammation after experimental cerebral ischaemia in mice

Directory of Open Access Journals (Sweden)

Adam eDenes

2014-01-01

Full Text Available Acute brain injury results in peripheral inflammatory changes, although the impact of these processes on neuronal death and neuroinflammation is currently unclear. To facilitate the translation of experimental studies to clinical benefit, it is vital to characterize the mechanisms by which acute brain injury induces peripheral inflammatory changes, and how these are affected by surgical manipulation in experimental models. Here we show that in mice, even mild surgical manipulation of extracranial tissues induced marked granulocyte mobilisation (300% and systemic induction of cytokines. However, intracranial changes induced by craniotomy, or subsequent induction of focal cerebral ischaemia were required to induce egress of CXCR2-positive granulocytes from the bone marrow. CXCR2 blockade resulted in reduced mobilisation of granulocytes from the bone marrow, caused an unexpected increase in circulating granulocytes, but failed to effect brain injury induced by cerebral ischaemia. We also demonstrate that isoflurane anaesthesia interferes with circulating leukocyte responses, which could contribute to the reported vascular and neuroprotective effects of isoflurane. In addition, no immunosuppression develops in the bone marrow after experimental stroke. Thus, experimental models of cerebral ischaemia are compromised by surgery and anaesthesia in proportion to the severity of surgical stress and overall tissue injury. Understanding the inherent confounding effects of surgical manipulation and development of new models of cerebral ischaemia with minimal surgical intervention could facilitate better understanding of interactions between inflammation and brain injury.

Friction-induced Vibrations in an Experimental Drill-string System for Various Friction Situations

NARCIS (Netherlands)

Mihajlovic, N.; Wouw, van de N.; Hendriks, M.P.M.; Nijmeijer, H.

2005-01-01

Friction-induced limit cycling deteriorates system performance in a wide variety of mechanical systems. In this paper, we study the way in which essential friction characteristics affect the occurrence and nature of friction-induced limit cycling in flexible rotor systems. This study is performed on

Sida rhomboidea.Roxb extract alleviates pathophysiological changes in experimental in vivo and in vitro models of high fat diet/fatty acid induced non-alcoholic steatohepatitis.

Science.gov (United States)

Thounaojam, Menaka C; Jadeja, Ravirajsinh N; Dandekar, Deven S; Devkar, Ranjitsinh V; Ramachandran, A V

2012-03-01

The present study was aim to evaluate protective role of Sida rhomboidea.Roxb (SR) extract against high fat diet/fatty acid induced pathophysiological alterations in experimental model of non-alcoholic steatohepatitis (NASH). Effect of SR extract on plasma levels of markers of hepatic damage, plasma and hepatic lipids, mitochondrial oxidative stress, status of enzymatic and non-enzymatic antioxidants and histopathological changes in liver tissue were evaluated in high fat diet fed C57BL/6J mice. Also, the effect of SR supplementation on lipid accumulation, lipid peroxidation, cytotoxicity and cell viability were evaluated in oleic acid treated HepG2 cells. Supplementation of NASH mice with SR extract prevented high fat diet induced elevation in plasma marker enzymes of liver damage, plasma and hepatic lipids, mitochondrial oxidative stress and compromised enzymatic and non-enzymatic antioxidant status. Further, addition of SR extract to in vitro HepG2 cells minimized oleic acid induced lipid accumulation, higher lipid peroxidation, cytotoxicity and reduced cell viability. These in vivo and in vitro studies suggest that SR extract has the potential of preventing high fat/fatty acid induced NASH mainly due to its hypolipidemic and antioxidant activities. Copyright © 2010 Elsevier GmbH. All rights reserved.

Extension of the energy range of the experimental activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium up to 65MeV.

Science.gov (United States)

Tárkányi, F; Ditrói, F; Takács, S; Hermanne, A; Ignatyuk, A V

2015-04-01

Activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium were extended up to 65MeV by using stacked foil irradiation and gamma spectrometry experimental methods. Experimental cross-sections data for the formation of the radionuclides (159)Dy, (157)Dy, (155)Dy, (161)Tb, (160)Tb, (156)Tb, (155)Tb, (154m2)Tb, (154m1)Tb, (154g)Tb, (153)Tb, (152)Tb and (151)Tb are reported in the 36-65MeV energy range, and compared with an old dataset from 1964. The experimental data were also compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS nuclear reaction model code as listed in the latest on-line libraries TENDL 2013. Copyright © 2015. Published by Elsevier Ltd.

Experimental demonstration of a parasite-induced immune response in wild birds: Darwin's finches and introduced nest flies.

Science.gov (United States)

Koop, Jennifer A H; Owen, Jeb P; Knutie, Sarah A; Aguilar, Maria A; Clayton, Dale H

2013-08-01

Ecological immunology aims to explain variation among hosts in the strength and efficacy of immunological defenses. However, a shortcoming has been the failure to link host immune responses to actual parasites under natural conditions. Here, we present one of the first experimental demonstrations of a parasite-induced immune response in a wild bird population. The recently introduced ectoparasitic nest fly Philornis downsi severely impacts the fitness of Darwin's finches and other land birds in the Galápagos Islands. An earlier study showed that female medium ground finches (Geospiza fortis) had P. downsi-binding antibodies correlating with presumed variation in fly exposure over time. In the current study, we experimentally manipulated fly abundance to test whether the fly does, in fact, cause changes in antibody levels. We manipulated P. downsi abundance in nests and quantified P. downsi-binding antibody levels of medium ground finch mothers, fathers, and nestlings. We also quantified host behaviors, such as preening, which can integrate with antibody-mediated defenses against ectoparasites. Philornis downsi-binding antibody levels were significantly higher among mothers at parasitized nests, compared to mothers at (fumigated) nonparasitized nests. Mothers with higher antibody levels tended to have fewer parasites in their nests, suggesting that antibodies play a role in defense against parasites. Mothers showed no behavioral changes that would enhance the effectiveness of the immune response. Neither adult males, nor nestlings, had P. downsi-induced immunological or behavioral responses that would enhance defense against flies. None of the parasitized nests fledged any offspring, despite the immune response by mothers. Thus, this study shows that, while the immune response of mothers appeared to be defensive, it was not sufficient to rescue current reproductive fitness. This study further shows the importance of testing the fitness consequences of immune

Radiation-induced conductivity of polynaphthoyl benzimidazole

Energy Technology Data Exchange (ETDEWEB)

Tiutnev, A P; Berlin, A M; Saenko, V S; Rusanov, A L; Korshak, V V

1985-01-01

The nonstationary radiation-induced conductivity of polynaphthoyl benzimidazole, synthesized by single-stage high-temperature catalytic polycondensation, is investigated experimentally. It is shown that the radiation-induced conductivity of this material is characterized by an anomalous (non-Gaussian) transfer of excess charge carriers. The activation energy of the delayed component (0.1 ms after pulse termination) is determined to be 0.12 eV; the volt-ampere characteristic of this component is nonlinear, with the coefficient of nonlinearity increasing with the intensity of the external electric field. Experimental results are interpreted on the basis of the phenomenological theory of jump conductivity proposed by Zviagin. 15 references.

The protective effect of vildagliptin in chronic experimental cyclosporine A-induced hepatotoxicity.

Science.gov (United States)

El-Sherbeeny, Nagla A; Nader, Manar A

2016-03-01

The study examined the effect of dipeptidyl peptidase-4 (DPP-4) inhibitor, vildagliptin, in cyclosporine (CsA)-induced hepatotoxicity. Rats were divided into 4 groups treated for 28 days: control (vehicle), vildagliptin (10 mg/kg, orally), CsA (20 mg/kg, s.c.), and CsA-vildagliptin group. Liver function was assessed by measuring serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyltransferase (γGT), lactate dehydrogenase (LDH), and albumin, and histopathological changes of liver were examined. Oxidative stress markers were evaluated. Assessment of nuclear factor-kappa B (NF-κB) activity in hepatic nuclear extract, serum DPP-4, and expression of Bax and Bcl2 were also done. CsA-induced hepatotoxicity was evidenced by increase in serum levels of AST, ALT, and γGT; a decrease in serum albumin; and a significant alteration in hepatic architecture. Also, significant increase in thiobarbituric acid reactive substance (TBARS) and decrease in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione (GSH) levels, increased expression Bax proteins with deceased expression of Bcl2, and increased hepatic activity of NF-κB and serum DPP-4 level were observed upon CsA treatment. Vildagliptin significantly improved all altered parameters induced by CsA administration. Vildagliptin has the potential to protect the liver against CsA-induced hepatotoxicity by reducing oxidative stress, DPP-4 activity, apoptosis, and inflammation.

Experimental Study on the Measurement of Water Bottom Vibration Induced by Underwater Drilling Blasting

Directory of Open Access Journals (Sweden)

Gu Wenbin

2015-01-01

Full Text Available Due to the lack of proper instrumentations and the difficulties in underwater measurements, the studies about water bottom vibration induced by underwater drilling blasting are seldom reported. In order to investigate the propagation and attenuation laws of blasting induced water bottom vibration, a water bottom vibration monitor was developed with consideration of the difficulties in underwater measurements. By means of this equipment, the actual water bottom vibration induced by underwater drilling blasting was measured in a field experiment. It shows that the water bottom vibration monitor could collect vibration signals quite effectively in underwater environments. The followed signal analysis shows that the characteristics of water bottom vibration and land ground vibration induced by the same underwater drilling blasting are quite different due to the different geological environments. The amplitude and frequency band of water bottom vibration both exceed those of land ground vibration. Water bottom vibration is mainly in low-frequency band that induced by blasting impact directly acts on rock. Besides the low-frequency component, land vibration contains another higher frequency band component that induced by followed water hammer wave acts on bank slope.

Experimental pain in human temporal muscle induced by hypertonic saline, potassium and acidity

DEFF Research Database (Denmark)

Jensen, K; Norup, M

1992-01-01

chloride (n = 12) induced significantly more pain than isotonic saline (ANOVA, p less than 0.0001). Compared to control injections, hypertonic saline and potassium chloride induced a significant reduction in pressure-pain threshold (ANOVA, p less than 0.0001 and p less than 0.05). Forty-eight percent...

Experimental model to induce obesity in rats Modelo experimental para induzir obesidade em ratos

Directory of Open Access Journals (Sweden)

Vinicius Von Diemen

2006-12-01

Full Text Available The etiology of obesity is multifactorial and is becoming a problem of public health, due to its increased prevalence and the consequent repercussion of its comorbidities on the health of the population. The great similarity and homology between the genomes of rodents and humans make these animal models a major tool to study conditions affecting humans, which can be simulated in rats. Obesity can be induced in animals by neuroendocrine, dietary or genetic changes. The most widely used models to induce obesity in rats are a lesion of the ventromedial hypothalamic nucleus (VMH by administering monosodium glutamate or a direct electrical lesion, ovariectomy, feeding on hypercaloric diets and genetic manipulation for obesity.A obesidade tem etiologia multifatorial e está se tornando um problema de saúde pública devido ao aumento da sua prevalência e a conseqüente repercusão das suas comorbidades na saúde da população. A grande similaridade e homologia entre os genomas dos roedores e dos humanos tornam esses modelos animais uma importante ferramenta para o estudo de condições que afetam os humanos e que podem ser simuladas em ratos. A obesidade pode ser induzida em animais com alterações neuroendócrinas, dietéticas ou genéticas. Os modelos mais utilizados para indução de obesidade em ratos são lesão do núcleo hipotalâmico venteromedial (VMH através da administração de glutamato monossódico ou lesão elétrica direta, ooforectomia, alimentação com dietas hipercalóricas e manipulação genética para obesidade.

Experimental study of directionally solidified ferromagnetic shape memory alloy under multi-field coupling

Energy Technology Data Exchange (ETDEWEB)

Zhu, Yuping, E-mail: zhuyuping@126.com [Institute of Geophysics, China Earthquake Administration, Beijing 100081 (China); Chen, Tao; Teng, Yao [Faculty of Civil Engineering and Mechanics, Jiangsu University, Zhenjiang 212013 (China); Liu, Bingfei [Airport College, Civil Aviation University of China, Tianjin 300300 (China); Xue, Lijun [Tianjin Key Laboratory of the Design and Intelligent Control of the Advanced Mechatronical System, School of Mechanical Engineering, Tianjin University of Technology, Tianjin 300384 (China)

2016-11-01

Directionally solidified, polycrystalline Ni–Mn–Ga is studied in this paper. The polycrystalline Ni–Mn–Ga samples were cut at different angles to solidification direction. The magnetic field induced strain under constant stress and the temperature-induced strain under constant magnetic field during the loading–unloading cycle were measured. The experimental results show that the mechanical behavior during the loading–unloading cycle of the material is nonlinear and anisotropic. Based on the experimental results, the effects of multi-field coupling factors, such as stress, magnetic field, temperature and cutting angle on the mechanical behaviors were analyzed. Some useful conclusions were obtained, which will provide guidance for practical applications. - Highlights: • The magnetic-induced strains in different directions are tested. • The temperature-induced strains in different directions are tested. • The effects of coupling factors on directional solidification samples are studied.

Sleep-inducing factors.

Science.gov (United States)

García-García, Fabio; Acosta-Peña, Eva; Venebra-Muñoz, Arturo; Murillo-Rodríguez, Eric

2009-08-01

Kuniomi Ishimori and Henri Piéron were the first researchers to introduce the concept and experimental evidence for a chemical factor that would presumably accumulate in the brain during waking and eventually induce sleep. This substance was named hypnotoxin. Currently, the variety of substances which have been shown to alter sleep includes peptides, cytokines, neurotransmitters and some substances of lipidic nature, many of which are well known for their involvement in other biological activities. In this chapter, we describe the sleep-inducing properties of the vasoactive intestinal peptide, prolactin, adenosine and anandamide.

Effect of Citrullus colocynthis hydro-alcoholic extract on hormonal and folliculogenesis process in estradiol valerate-induced PCOs rats model: An experimental study

Directory of Open Access Journals (Sweden)

Mohammad Hossein Barzegar

2017-12-01

Full Text Available Background: Citrullus colocynthis (CCT is used as the anti-diabetic and antioxidant agent. Polycystic ovarian syndrome (PCOS is a reproductive disorder which level of gonadotropins and sexual hormones are imbalanced. Objective: We evaluated the effect of CCT hydro-alcoholic extract on hormonal and folliculogenesis process in estradiol valerate-induced PCOs rats’ model. Materials and Methods: 40 female adult Wistar rats divided into five groups (n=8each: Group I (control only injected by sesame oil as estradiol valerate solvent, group II (Sham was orally received normal saline after estradiol valerate- induced polycystic ovarian syndrome (4 mg/rat estradiol valerate, intramuscularly, and three experimental groups, that after induction of PCOS within 60 days, received orally 50 mg/kg CCT extract (group III, 50mg/kg metformin (group IV, and CCT extract+ metformin (group V for 20 days. The serum concentration level of luteinizing, testosterone and follicle stimulating hormones were measured using ELISA method and the serum concentration level of glucose were measured using the oxidative method (glucose meter. Histological study of ovary tissue carried out by hematoxylin-eosin staining. Results: There was a significant reduction in luteinizing hormone and testosterone in III-V groups compared to Sham group, whereas follicle stimulating hormone in III-V groups was not significantly changed in comparison with Sham group. Histological investigations showed a significant increase in number of preantral and antral follicles and corpus luteum in the experimental groups compared to group II. Conclusion: Marked improvement in hormonal and histological symptoms of PCOS may be due to CCT effects hence, CCT can potentially be considered as an effective drug for treatment of PCOS

Experimental Study on the Measurement of Water Bottom Vibration Induced by Underwater Drilling Blasting

OpenAIRE

Wenbin, Gu; Jianghai, Chen; Zhenxiong, Wang; Zhihua, Wang; Jianqing, Liu; Ming, Lu

2015-01-01

Due to the lack of proper instrumentations and the difficulties in underwater measurements, the studies about water bottom vibration induced by underwater drilling blasting are seldom reported. In order to investigate the propagation and attenuation laws of blasting induced water bottom vibration, a water bottom vibration monitor was developed with consideration of the difficulties in underwater measurements. By means of this equipment, the actual water bottom vibration induced by underwater ...

Hepatoprotective activity of Musa paradisiaca on experimental animal models.

Science.gov (United States)

Nirmala, M; Girija, K; Lakshman, K; Divya, T

2012-01-01

To investigate the hepatoprotective activity of stem of Musa paradisiaca (M. paradisiaca) in CCl4 and paracetamol induced hepatotoxicity models in rats. Hepatoprotective activity of alcoholic and aqueous extracts of stem of M. paradisiaca was demonstrated by using two experimentally induced hepatotoxicity models. Administration of hepatotoxins (CCl4 and paracetamol) showed significant biochemical and histological deteriorations in the liver of experimental animals. Pretreatment with alcoholic extract (500 mg/kg), more significantly and to a lesser extent the alcoholic extract (250 mg/kg) and aqueous extract (500 mg/kg), reduced the elevated levels of the serum enzymes like serum glutamic-oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), alkaline phosphatase (ALP) and bilirubin levels and alcoholic and aqueous extracts reversed the hepatic damage towards the normal, which further evidenced the hepatoprotective activity of stem of M. paradisiaca. The alcoholic extract at doses of 250 and 500 mg/kg, p.o. and aqueous extract at a dose of 500 mg/kg, p.o. of stem of M. paradisiaca have significant effect on the liver of CCl4 and paracetamol induced hepatotoxicity animal models.

Experimental demonstration of spinor slow light

Science.gov (United States)

Lee, Meng-Jung; Ruseckas, Julius; Lee, Chin-Yuan; Kudriašov, Viačeslav; Chang, Kao-Fang; Cho, Hung-Wen; JuzeliÅ«nas, Gediminas; Yu, Ite A.

2016-03-01

Over the last decade there has been a continuing interest in slow and stored light based on the electromagnetically induced transparency (EIT) effect, because of their potential applications in quantum information manipulation. However, previous experimental works all dealt with the single-component slow light which cannot be employed as a qubit. In this work, we report the first experimental demonstration of two-component or spinor slow light (SSL) using a double tripod (DT) atom-light coupling scheme. The oscillations between the two components, similar to the Rabi oscillation of a two-level system or a qubit, were observed. Single-photon SSL can be considered as two-color qubits. We experimentally demonstrated a possible application of the DT scheme as quantum memory and quantum rotator for the two-color qubits. This work opens up a new direction in the slow light research.

Experimental setup and first measurement of DNA damage induced along and around an antiproton beam

International Nuclear Information System (INIS)

Kavanagh, J.N.; Currell, F.J.; Prise, K.M.; Schettino, G.; Currell, F.J.; Timson, D.J.; Holzscheiter, M.H.; Bassler, N.; Herrmann, R.

2010-01-01

Radiotherapy employs ionizing radiation to induce lethal DNA lesions in cancer cells while minimizing damage to healthy tissues. Due to their pattern of energy deposition, better therapeutic outcomes can, in theory, be achieved with ions compared to photons. Antiprotons have been proposed to offer a further enhancement due to their annihilation at the end of the path. The work presented here aimed to establish and validate an experimental procedure for the quantification of plasmid and genomic DNA damage resulting from antiproton exposure. Immunocytochemistry was used to assess DNA damage in directly and indirectly exposed human fibroblasts irradiated in both plateau and Bragg peak regions of a 126 MeV antiproton beam at CERN. Cells were stained post irradiation with an anti-γ-H2AX antibody. Quantification of the γ-H2AX foci-dose relationship is consistent with a linear increase in the Bragg peak region. A qualitative analysis of the foci detected in the Bragg peak and plateau region indicates significant differences highlighting the different severity of DNA lesions produced along the particle path. Irradiation of desalted plasmid DNA with 5 Gy antiprotons at the Bragg peak resulted in a significant portion of linear plasmid in the resultant solution. (authors)

A comparison between experimental results and a mathematical model of the oxidation reactions induced by radiation of ferrous ions

International Nuclear Information System (INIS)

Sanchez-Mejorada, G.; Frias, D.; Negron-Mendoza, A.; Ramos-Bernal, S.

2008-01-01

The dependence of the response of chemical dosimeters as a function of the irradiation temperature is an important issue that has not yet been addressed within a mathematical modeling framework. The temperature dependence of the dose-response function has to be taken into account in practical applications, mainly in frozen food sterilization by radiation. Significant errors may occur if the dependence of the dosimeter response on the irradiation temperature is not taken into account properly. The experimental results obtained irradiating iron salt solutions at different temperatures below and above 0 deg. C show that the change in the valence of Fe 2+ as a function of dose are linear for both liquid and frozen solutions. This led us to conclude that the iron salt solution seems suitable for low-temperature applications having a linear dose-response up to 600 Gy, despite a progressive decrease of sensitivity as temperature decreases. A nonlinear differential model for the kinetics of reactions induced by radiation in iron salt solutions was established. In the model a temperature correction factor was included in order to take into account abrupt changes observed in the kinetics of the chemical process when the irradiated solution's allotropic phase changes from liquid to solid (ice). Fitting the kinetic model to the experimental results at different temperatures we found the temperature correction factors

Mechanisms of cell death induced by infusion sets leachables in in vitro experimental settings.

Science.gov (United States)

Kozlovskaya, Luba; Stepensky, David

2015-01-30

Leachable materials that are released from infusion sets during their use can induce local and systemic toxic effects. We studied the mechanisms and kinetics of cell death induced by infusion sets leachates in vitro using L-929 and bEnd. 3 cells. Changes in cell morphology and metabolic activity were determined using light microscopy and the MTT test, respectively. Detailed analysis of the mechanisms of cell death was performed using membrane integrity and caspases 3 and 7 activity tests, annexin V-FITC/7-AAD analysis by FACS, and DAPI nuclear staining followed by confocal microscopy. Infusion sets released toxic leachables and induced toxic effects. Latex flashball was the most toxic part of the studied infusion sets, and it potently induced cell oncosis via increased permeability of the cell membrane. Latex-induced decrease in cells metabolic activity and cell death were not accompanied by activation of caspases 3 and 7, changes in nuclear morphology, or substantial annexin V-FITC cell staining. Leachables from the tube part of the infusion sets were less toxic, and induced some biochemical changes without altering the cells morphology. Further studies are needed to reveal the in vivo toxicity of infusion sets and its correlation with the results of in vitro toxicity studies. Copyright © 2014 Elsevier B.V. All rights reserved.

Dihydrotanshinone I, a natural product, ameliorates DSS-induced experimental ulcerative colitis in mice.

Science.gov (United States)

Guo, Yanling; Wu, Xiaxia; Wu, Qin; Lu, Yuanfu; Shi, Jingshan; Chen, Xiuping

2018-04-01

Ulcerative colitis (UC) is a chronic and relapsing inflammatory disorder of the colon and rectum with increasing morbidity in recent years. 15,16-dihydrotanshinone Ӏ (DHT) is a natural product with multiple bioactivities. In this study, we aimed to investigate the protective effect and potential mechanisms of DHT on UC. Dextran sulfate sodium salt (DSS) was administrated in drinking water for 7 days to induce UC in mice. DHT (10 and 25 mg/kg) significantly alleviated DSS-induced body weight loss, disease activity index (DAI) scores, and improved histological alterations of colon tissues. DHT inhibited the myeloperoxidase (MPO) activity, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in colon tissues and decreased serum levels of TNF-α, IL-1β, IL-6, and high-mobility group box 1 (HMGB1). Furthermore, increased expression of kinases receptor-interacting protein 1 (RIP1), RIP3, mixed lineage kinase domain-like protein (MLKL) and decreased expression of caspase-8 in colon tissues were partially restored by DHT. In LPS-stimulated RAW264.7 macrophages, DHT significantly inhibited generation of nitric oxide, IL-6, TNF-α and protein expression of iNOS, COX-2. In addition, increased expression of iNOS, COX-2, and phosphorylated RIP1, RIP3, MLKL in response to LPS plus Z-VAD (LZ) were also suppressed by DHT. DHT had no effect on TNF-α + BV6 + Z-VAD (TBZ) induced phosphorylation of RIPs and MLKL in HT29 cells. Especially, DHT showed no effect on LZ and TBZ-induced necroptosis in RAW264.7 and HT29 cells, respectively. In summary, DHT alleviated DSS-induced UC in mice by suppressing pro-inflammatory mediators and regulating RIPs-MLKL-caspase-8 axis. Copyright © 2018 Elsevier Inc. All rights reserved.

Protective effect of curcumin on experimentally induced arthritic rats: detailed histopathological study of the joints and white blood cell count

Science.gov (United States)

Kamarudin, Taty Anna; Othman, Faizah; Mohd Ramli, Elvy Suhana; Md Isa, Nurismah; Das, Srijit

2012-01-01

Curcuma longa (turmeric) rhizomes contains curcumin, an active compound which possesses anti-inflammatory effects. Collagen-induced arthritis (CIA) is an accepted experimental animal model of rheumatoid arthritis. The present study aimed to observe the histological changes in the joints of experimental arthritic rats treated with curcumin. Twenty four male Sprague-Dawley (approximately 7 weeks-old) rats were randomly divided into four groups. Three groups were immunized with 150 µg collagen. All rats with established CIA, with arthritis scores exceeding 1, were orally treated with betamethasone (0.5 mg/ml/kg body weight), curcumin (110 mg/ml/kg body weight) or olive oil (1.0 ml/kg body weight) daily, for two weeks. One remaining group was kept as normal control. Treatment with 110 mg/ml/kg curcumin showed significant mean differences in the average white blood cell (WBC) count (pPannus formation scores showed that curcumin supplementation successfully suppressed the pannus formation process that occurred in the articular cartilage of the CIA joints. The mean difference for histological scores for the curcumin group was insignificant compared to the betamethasone treated group. It is concluded that supplementation of curcumin has protective effect on the histopathological and degenerative changes in the joints of CIA rats which was at par with betamethasone. PMID:27366139

Protective effect of curcumin on experimentally induced arthritic rats: detailed histopathological study of the joints and white blood cell count.

Science.gov (United States)

Kamarudin, Taty Anna; Othman, Faizah; Mohd Ramli, Elvy Suhana; Md Isa, Nurismah; Das, Srijit

2012-01-01

Curcuma longa (turmeric) rhizomes contains curcumin, an active compound which possesses anti-inflammatory effects. Collagen-induced arthritis (CIA) is an accepted experimental animal model of rheumatoid arthritis. The present study aimed to observe the histological changes in the joints of experimental arthritic rats treated with curcumin. Twenty four male Sprague-Dawley (approximately 7 weeks-old) rats were randomly divided into four groups. Three groups were immunized with 150 µg collagen. All rats with established CIA, with arthritis scores exceeding 1, were orally treated with betamethasone (0.5 mg/ml/kg body weight), curcumin (110 mg/ml/kg body weight) or olive oil (1.0 ml/kg body weight) daily, for two weeks. One remaining group was kept as normal control. Treatment with 110 mg/ml/kg curcumin showed significant mean differences in the average white blood cell (WBC) count (pcurcumin supplementation successfully suppressed the pannus formation process that occurred in the articular cartilage of the CIA joints. The mean difference for histological scores for the curcumin group was insignificant compared to the betamethasone treated group. It is concluded that supplementation of curcumin has protective effect on the histopathological and degenerative changes in the joints of CIA rats which was at par with betamethasone.

Endothelial Dysfunction in Experimental Models of Arterial Hypertension: Cause or Consequence?

Directory of Open Access Journals (Sweden)

Iveta Bernatova

2014-01-01

Full Text Available Hypertension is a risk factor for other cardiovascular diseases and endothelial dysfunction was found in humans as well as in various commonly employed animal experimental models of arterial hypertension. Data from the literature indicate that, in general, endothelial dysfunction would not be the cause of experimental hypertension and may rather be secondary, that is, resulting from high blood pressure (BP. The initial mechanism of endothelial dysfunction itself may be associated with a lack of endothelium-derived relaxing factors (mainly nitric oxide and/or accentuation of various endothelium-derived constricting factors. The involvement and role of endothelium-derived factors in the development of endothelial dysfunction in individual experimental models of hypertension may vary, depending on the triggering stimulus, strain, age, and vascular bed investigated. This brief review was focused on the participation of endothelial dysfunction, individual endothelium-derived factors, and their mechanisms of action in the development of high BP in the most frequently used rodent experimental models of arterial hypertension, including nitric oxide deficient models, spontaneous (prehypertension, stress-induced hypertension, and selected pharmacological and diet-induced models.

Surface solitons of four-wave mixing in an electromagnetically induced lattice

International Nuclear Information System (INIS)

Zhang, Yanpeng; Yuan, Chenzhi; Zhang, Yiqi; Zheng, Huaibin; Chen, Haixia; Li, Changbiao; Wang, Zhiguo; Xiao, Min

2013-01-01

By creating lattice states with two-dimensional spatial periodic atomic coherence, we report an experimental demonstration of generating two-dimensional surface solitons of a four-wave mixing signal in an electromagnetically induced lattice composed of two electromagnetically induced gratings with different orientations in an atomic medium, each of which can support a one-dimensional surface soliton. The surface solitons can be well controlled by different experimental parameters, such as probe frequency, pump power, and beam incident angles, and can be affected by coherent induced defect states. (letter)

Penetration of corrosion products and corrosion-induced cracking in reinforced cementitious materials

DEFF Research Database (Denmark)

Michel, Alexander; Pease, Brad J.; Peterova, Adela

2014-01-01

This paper describes experimental investigations on corrosion-induced deterioration in reinforced cementitious materials and the subsequent development and implementation of a novel conceptual model. Rejnforced mortar specimens of varying water-to-cement ratios were subjected to current-induced c......This paper describes experimental investigations on corrosion-induced deterioration in reinforced cementitious materials and the subsequent development and implementation of a novel conceptual model. Rejnforced mortar specimens of varying water-to-cement ratios were subjected to current......-dependent concentrations of corrosion products averaged through the specimen thickness. Digital image correlation (DIC) was used to measure corrosion-induced deformations including deformations between steel and cementitious matrix as well as formation and propagation of corrosion-induced cracks. Based on experimental...... observations, a conceptual model was developed to describe the penetration of solid corrosion products into capillary pores of the cementitious matrix. Only capillary pores within a corrosion accommodating region (CAR), i.e. in close proximity of the steel reinforcement, were considered accessible...

Neutropenia induced in outbred mice by a simplified low-dose cyclophosphamide regimen: characterization and applicability to diverse experimental models of infectious diseases

Directory of Open Access Journals (Sweden)

Zapata Ana X

2006-03-01

Full Text Available Abstract Background For its low cost and ease of handling, the mouse remains the preferred experimental animal for preclinical tests. To avoid the interaction of the animal immune system, in vivo antibiotic pharmacodynamic studies often employ cyclophosphamide (CPM to induce neutropenia. Although high doses (350–450 mg/kg are still used and their effects on mouse leukocytes have been described, a lower dose (250 mg/kg is widely preferred today, but the characteristics and applicability of this approach in outbred mice have not been determined. Methods Fifteen female ICR mice were injected intraperitoneally with 150 and 100 mg/kg of CPM on days 1 and 4, respectively. Blood samples (~160 μL were drawn from the retro-orbital sinus of each mouse on days 1, 4, 5, 6, 7 and 11. Leukocytes were counted manually and the number of granulocytes was based on microscopic examination of Wright-stained smears. The impact of neutropenia induced by this method was then determined with a variety of pathogens in three different murine models of human infections: pneumonia (Klebsiella pneumoniae, Streptococcus pneumoniae, Staphylococcus aureus, meningoencephalitis (S. pneumoniae, and the thigh model (S. aureus, Escherichia coli, Bacteroides fragilis. Results The basal count of leukocytes was within the normal range for outbred mice. On day 4, there was an 84% reduction in total white blood cells, and by day 5 the leukopenia reached its nadir (370 ± 84 cells/mm3. Profound neutropenia (≤10 neutrophils/mm3 was demonstrated at day 4 and persisted through days 5 and 6. Lymphocytes and monocytes had a 92% and 96% decline between days 1 and 5, respectively. Leukocytes recovered completely by day 11. Mice immunosupressed under this protocol displayed clinical and microbiological patterns of progressive and lethal infectious diseases after inoculation in different organs with diverse human pathogens. Conclusion A CPM total dose of 250 mg/kg is sufficient to induce

Approaching Stan Laurel's illusion: the self-induced rubber hand phenomenon.

Science.gov (United States)

Neuf, Hartmut; Hamburger, Kai

2013-01-01

The classical rubber hand illusion is induced by an experimenter (eg stimulation with a brush) and usually realized with some sort of visual occlusion. Here, we demonstrate a new phenomenon: the self-induced rubber hand illusion. It is possible to elicit the feeling of a third hand without any help from an experimenter and under conditions of no occlusion. The findings are discussed within the context of neural plasticity.

Numerical and experimental depth profile analyses of coated and attached layers by laser-induced breakdown spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Ardakani, H. Afkhami [Laser and Plasma Research Institute, Shahid Beheshti University, G. C., Evin, Tehran (Iran, Islamic Republic of); Tavassoli, S.H., E-mail: h-tavassoli@sbu.ac.i [Laser and Plasma Research Institute, Shahid Beheshti University, G. C., Evin, Tehran (Iran, Islamic Republic of)

2010-03-15

Laser-induced breakdown spectroscopy (LIBS) is applied for depth profile analysis of different thicknesses of copper foils attached on steel and aluminum substrates. In order to account interfacial effects, depth profile analysis of copper coated on steel is also carried out. Experiments are done at ambient air and at two different wavelengths of 266 and 1064 nm of a Nd:YAG laser with pulse durations of 5 ns. A three-dimensional model of multi-pulse laser ablation is introduced on the base of normal evaporation mechanism and the simulation results are compared with the experiments. A normalized concentration (C{sup N}) is introduced for determination of interface position and results are compared with the usually used normalized intensity (I{sup N}). The effect of coating thickness on average ablation rate and resolution of depth profiling are examined. There is a correlation coefficient higher than 0.95 between the model and experimental depth profiles based on the C{sup N} method. Depth profile analysis on the base of C{sup N} method shows a better depth resolution in comparison with I{sup N} method .Increase in the layer thickness, leads to a decrease in the ablation rate.

Modelling irradiation-induced softening in BCC iron by crystal plasticity approach

International Nuclear Information System (INIS)

Xiao, Xiazi; Terentyev, Dmitry; Yu, Long; Song, Dingkun; Bakaev, A.; Duan, Huiling

2015-01-01

Crystal plasticity model (CPM) for BCC iron to account for radiation-induced strain softening is proposed. CPM is based on the plastically-driven and thermally-activated removal of dislocation loops. Atomistic simulations are applied to parameterize dislocation-defect interactions. Combining experimental microstructures, defect-hardening/absorption rules from atomistic simulations, and CPM fitted to properties of non-irradiated iron, the model achieves a good agreement with experimental data regarding radiation-induced strain softening and flow stress increase under neutron irradiation. - Highlights: • A stress- and thermal-activated defect absorption model is proposed for the dislocation-loop interaction. • A temperature-dependent plasticity theory is proposed for the irradiation-induced strain softening of irradiated BCC metals. • The numerical results of the model match with the corresponding experimental data.

Modelling irradiation-induced softening in BCC iron by crystal plasticity approach

Energy Technology Data Exchange (ETDEWEB)

Xiao, Xiazi [State Key Laboratory for Turbulence and Complex System, Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing 100871 (China); CAPT, HEDPS and IFSA Collaborative Innovation Center of MoE, Peking University, Beijing 100871 (China); Terentyev, Dmitry, E-mail: dterenty@SCKCEN.BE [Structural Material Group, Institute of Nuclear Materials Science, SCK-CEN, Mol (Belgium); Yu, Long; Song, Dingkun [State Key Laboratory for Turbulence and Complex System, Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing 100871 (China); Bakaev, A. [Structural Material Group, Institute of Nuclear Materials Science, SCK-CEN, Mol (Belgium); Duan, Huiling, E-mail: hlduan@pku.edu.cn [State Key Laboratory for Turbulence and Complex System, Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing 100871 (China); CAPT, HEDPS and IFSA Collaborative Innovation Center of MoE, Peking University, Beijing 100871 (China)

2015-11-15

Crystal plasticity model (CPM) for BCC iron to account for radiation-induced strain softening is proposed. CPM is based on the plastically-driven and thermally-activated removal of dislocation loops. Atomistic simulations are applied to parameterize dislocation-defect interactions. Combining experimental microstructures, defect-hardening/absorption rules from atomistic simulations, and CPM fitted to properties of non-irradiated iron, the model achieves a good agreement with experimental data regarding radiation-induced strain softening and flow stress increase under neutron irradiation. - Highlights: • A stress- and thermal-activated defect absorption model is proposed for the dislocation-loop interaction. • A temperature-dependent plasticity theory is proposed for the irradiation-induced strain softening of irradiated BCC metals. • The numerical results of the model match with the corresponding experimental data.

Autosomal recessive type II hereditary motor and sensory neuropathy with acrodystrophy.

Science.gov (United States)

Thomas, P K; Claus, D; King, R H

1999-02-01

A family is described with presumed autosomal recessive inheritance in which three siblings developed a progressive neuropathy that combined limb weakness and severe distal sensory loss leading to prominent mutilating changes. Electrophysiological and nerve biopsy findings indicated an axonopathy. The disorder is therefore classifiable as type II hereditary motor and sensory neuropathy (HMSN II). The clinical features differ from those reported in previously described cases of autosomal recessive HMSN II. This disorder may therefore represent a new variant.

TFTR Experimental Data Analysis Collaboration

International Nuclear Information System (INIS)

Callen, J.D.

1993-01-01

The research performed under the second year of this three-year grant has concentrated on a few key TFTR experimental data analysis issues: MHD mode identification and effects on supershots; identification of new MHD modes; MHD mode theory-experiment comparisons; local electron heat transport inferred from impurity-induced cool pulses; and some other topics. Progress in these areas and activities undertaken in conjunction with this grant are summarized briefly in this report

Experimental models of demyelination and remyelination.

Science.gov (United States)

Torre-Fuentes, L; Moreno-Jiménez, L; Pytel, V; Matías-Guiu, J A; Gómez-Pinedo, U; Matías-Guiu, J

2017-08-29

Experimental animal models constitute a useful tool to deepen our knowledge of central nervous system disorders. In the case of multiple sclerosis, however, there is no such specific model able to provide an overview of the disease; multiple models covering the different pathophysiological features of the disease are therefore necessary. We reviewed the different in vitro and in vivo experimental models used in multiple sclerosis research. Concerning in vitro models, we analysed cell cultures and slice models. As for in vivo models, we examined such models of autoimmunity and inflammation as experimental allergic encephalitis in different animals and virus-induced demyelinating diseases. Furthermore, we analysed models of demyelination and remyelination, including chemical lesions caused by cuprizone, lysolecithin, and ethidium bromide; zebrafish; and transgenic models. Experimental models provide a deeper understanding of the different pathogenic mechanisms involved in multiple sclerosis. Choosing one model or another depends on the specific aims of the study. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Experimental investigation of defect criticality in FRP laminate composites

Science.gov (United States)

Joyce, Peter James

1999-11-01

This work examines the defect criticality of fiber reinforced polymer Composites. The objective is to determine the sensitivity of the finished composite to various process-induced defects. This work focuses on two different classes of process-induced defects; (1) fiber waviness in high performance carbon-fiber reinforced unidirectional composites and (2) void volume in low cost glass-fabric reinforced composites. The role of fiber waviness in the compressive response of unidirectional composites has been studied by a number of other investigators. Because of difficulties associated with producing real composites with varying levels of fiber waviness, most experimental studies of fiber waviness have evaluated composites with artificially induced fiber waviness. Furthermore, most experimental studies have been concentrated on the effects of out-of-plane fiber waviness. The objective of this work is to evaluate the effects of in-plane fiber waviness naturally occurring in autoclave consolidated thermoplastic laminates. The first phase of this project involved the development of a simple technique for measuring the resulting fiber waviness levels. An experimental investigation of the compression strength reduction in composites with in-plane fiber waviness followed. The experimental program included carbon-fiber reinforced thermoplastic composites manufactured from prepreg tape by hand layup, and carbon-fiber and glass-fiber reinforced composites manufactured from an experimental powder towpreg by filament winding and autoclave consolidation. The compression specimens exhibited kink band failure in the prepreg composite and varying amounts of longitudinal splitting and kink banding in the towpreg composites. The compression test results demonstrated the same trend as predicted by microbudding theory but the overall quantitative correlation was poor. The second thrust of this research evaluated void effects in resin transfer molded composites. Much of the existing

Nuclear fission: a review of experimental advances and phenomenology

Science.gov (United States)

Andreyev, A. N.; Nishio, K.; Schmidt, K.-H.

2018-01-01

In the last two decades, through technological, experimental and theoretical advances, the situation in experimental fission studies has changed dramatically. With the use of advanced production and detection techniques both much more detailed and precise information can now be obtained for the traditional regions of fission research and, crucially, new regions of nuclei have become routinely accessible for fission studies. This work first of all reviews the recent developments in experimental fission techniques, in particular the resurgence of transfer-induced fission reactions with light and heavy ions, the emerging use of inverse-kinematic approaches, both at Coulomb and relativistic energies, and of fission studies with radioactive beams. The emphasis on the fission-fragment mass and charge distributions will be made in this work, though some of the other fission observables, such as prompt neutron and γ-ray emission will also be reviewed. A particular attention will be given to the low-energy fission in the so far scarcely explored nuclei in the very neutron-deficient lead region. They recently became the focus for several complementary experimental studies, such as β-delayed fission with radioactive beams at ISOLDE(CERN), Coulex-induced fission of relativistic secondary beams at FRS(GSI), and several prompt fusion–fission studies. The synergy of these approaches allows a unique insight in the new region of asymmetric fission around {\\hspace{0pt}}180 Hg, recently discovered at ISOLDE. Recent extensive theoretical efforts in this region will also be outlined. The unprecedented high-quality data for fission fragments, completely identified in Z and A, by means of reactions in inverse kinematics at FRS(GSI) and VAMOS(GANIL) will be also reviewed. These experiments explored an extended range of mercury-to-californium elements, spanning from the neutron-deficient to neutron-rich nuclides, and covering both asymmetric, symmetric and transitional fission regions

Experimental model of the burn wound topical treatment

Directory of Open Access Journals (Sweden)

Amra Čabaravdić

2003-11-01

Full Text Available AbstractBACKGROUND AND PURPOSE:Clinical research of drugs is a researching step subsequent to the preclinical studies in experimental animals. The aim of our research was to evaluate animal model of wound healing process after the burninducement and effects of the ointment containing natural plants on the process of burn healing.MATERIAL AND METHODS:Burn wounds were experimentally induced in two species of experimental animals which were treated with topically applied herbal preparation with concomitant monitoring of the healing process. Experimental groups (1 of 15 animals each (mice and rats, while control group (2 of 10 animals each (mice and rats that were not being treated with herbal ointment. After the hair removal, burn was induced on the back of animals by heated brass seal. Different clinical symptoms including oedema of surrounding tissue, redness, exudation, size of the burn surface, histological and microbiological findings were monitored on the days 1, 3, 7, 14 and 21. A statistically significant difference was observed throughout descriptive statistics and paired Student's t-test.CONCLUSION:Physiological healing processes of the acute burn wound following the topical application of herbal preparation can be monitored on the utilized animal model. A three-week treatment resulted in the 90% of completed epithelization in both animal species, indicating the effectiveness of topically applied herbal preparation.

Immunohistochemical and transcriptome analyses indicate complex breakdown of axonal transport mechanisms in canine distemper leukoencephalitis.

Science.gov (United States)

Spitzbarth, Ingo; Lempp, Charlotte; Kegler, Kristel; Ulrich, Reiner; Kalkuhl, Arno; Deschl, Ulrich; Baumgärtner, Wolfgang; Seehusen, Frauke

2016-07-01

CDV-DL (Canine distemper virus-induced demyelinating leukoencephalitis) represents a spontaneously occurring animal model for demyelinating disorders. Axonopathy represents a key pathomechanism in this disease; however, its underlying pathogenesis has not been addressed in detail so far. This study aimed at the characterization of axonal cytoskeletal, transport, and potential regenerative changes with a parallel focus upon Schwann cell remyelination. Immunohistochemistry of canine cerebellar tissue as well as a comparative analysis of genes from an independent microarray study were performed. Increased axonal immunoreactivity for nonphosphorylated neurofilament was followed by loss of cytoskeletal and motor proteins. Interestingly, a subset of genes encoding for neurofilament subunits and motor proteins was up-regulated in the chronic stage compared to dogs with subacute CDV-DL. However, immunohistochemically, hints for axonal regeneration were restricted to up-regulated axonal positivity of hypoxia-inducible factor 1 alpha, while growth-associated protein 43, erythropoietin and its receptor were not or even down-regulated. Periaxin-positive structures, indicative of Schwann cell remyelination, were only detected within few advanced lesions. The present findings demonstrate a complex sequence of axonal cytoskeletal breakdown mechanisms. Moreover, though sparse, this is the first report of Schwann cell remyelination in CDV-DL. Facilitation of these very limited endogenous regenerative responses represents an important topic for future research.

Multislice quantitative computed tomography allows early detection of bone mineral density alterations induced by atherogenic diet in a growing rat experimental model

International Nuclear Information System (INIS)

Gubert, M.J.; Monforte, F.; Calo, C.; Lylyk, P.; Friedman, M.F.; Gamba, C.A.

2012-01-01

Purpose. To demonstrate the utility of Multislice Quantitative Computed Tomography (MS-QCT) in the early detection of mandibular bone mineral density (BMD) alterations induced by an atherogenic diet in a growing rat experimental model. Materials and Methods. Male weanling Wistar rats (n =16) were divided by body weight (Wt) into 2 groups: control (C) and experimental (E), with no significant differences in the mean initial Wt (p>0.05). C was fed rodent stock diet ad libitum, and E an atherogenic diet for 3 weeks (3w). Zoometry (body weight and length) and diet intake (g/100g rat/day) were monitored. At 3 w in serum (mg/dL) lipidlipoprotein profile was studied: total cholesterol (t-C), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), non-HDL cholesterol (non-HDL-C) and MSQCT (Philips 64 CT, quantified with the eFilm Workstation 2.1) in seven mandibular areas (MA): n. 1 to 4: from chin to mandibular foramen, n. 5: coronoid process, n. 6: condylar process, n. 7: angular process. Statistics: Pearson's correlation between BMD in each MA and serum t-C. p 0.05). Correlation coefficients (r) and their significance levels (p) were relevant in 5/7 MA. MA1:-0.580 (p=0.019), MA2:-0.709 (p=0.002), MA3:-0.635 (p=0.008), MA5:-0.674 (p=0.004), MA6:-0.564 (p=0.023). Conclusions. These results suggest that MS-QCT is an imaging diagnostic method that allows the early detection of mandible bone architecture alterations induced by an atherogenic diet. Inverse correlation between BMD and t-C would indicate an association between an atherogenic diet intake and potential temporomandibular disorders. (authors)

Differential effects of experimental and cold-induced hyperthyroidism on factors inducing rat liver oxidative damage

OpenAIRE

Venditti, Paola; Pamplona Gras, Reinald; Ayala, Victoria; Rosa, R. de; Caldarone, G.; Di Meo, S.

2006-01-01

Thyroid hormone-induced increase in metabolic rates is often associated with increased oxidative stress. The aim of the present study was to investigate the contribution of iodothyronines to liver oxidative stress in the functional hyperthyroidism elicited by cold, using as models cold-exposed and 3,5,3'-triiodothyronine (T-3)- or thyroxine (T-4)-treated rats. The hyperthyroid state was always associated with increases in both oxidative capacity and oxidative damage of the tissue. The most ex...

Comparison of acute effect of systemic versus intravitreal infliximab treatment in an experimental model of endotoxin-induced uveitis.

Science.gov (United States)

Yuksel, Erdem; Hasanreisoglu, Berati; Yuksel, Nilay; Yilmaz, Guldal; Ercin, Ugur; Bilgihan, Ayse

2014-02-01

In this study, we investigated the efficacy of systemic and intravitreal (IV) infliximab treatments and compared these 2 different treatment modalities in an experimental model of endotoxin-induced uveitis (EIU). Twenty-four white New Zealand rabbits were equally divided into 4 groups. Group 1 received IV injection of lipopolysaccharide (LPS), group 2 received IV injections of LPS and saline, group 3 received IV LPS and IV 2 mg/0.1 cc infliximab, and group 4 received IV LPS and 5 mg/kg intravenous infliximab. Inflammation was determined with objective and subjective tests. The subjective test was clinical determination of uveitis, the objective tests were determination of protein concentrations and tumor necrosis factor alpha (TNF-α) levels and histopathology. Clinical examination score was lower in group 3 and group 4 (4±0.6 and 3.5±1.6, respectively) when compared with group 1 (P=0.02; P=0.04, respectively) and group 2. In group 3 and 4, the aqueous and vitreous protein and TNF-α concentration measured significantly lower than group 1 and 2. In histopathologic examination, there was no statistically significant difference between group 1, 2, and 3 (3.5±0.5, 3.6±0.5, 3.6±0.5, respectively). However, the lowest histopathologic inflammation was determined in group 4 (2.5±0.5) (compared with group 1 and group 3, respectively; P=0.03; P=0.014). In a rabbit model of experimental EIU, intravenous administration of infliximab was more effective than IV route in an acute period.

Comparison of 252Cf time correlated induced fission with AmLi induced fission on fresh MTR reserach reactor fuel

Energy Technology Data Exchange (ETDEWEB)

Joshi, Jay Prakash [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-05-01

The objectives of this project are to calibrate the Advanced Experimental Fuel Counter (AEFC), benchmark MCNP simulations using experimental results, investigate the effects of change in fuel assembly geometry, and finally to show the boost in doubles count rates with 252Cf active soruces due to the time correlated induced fission (TCIF) effect.

Ratcheting problems for ITER [International Thermonuclear Experimental Reactor

International Nuclear Information System (INIS)

Majumdar, S.

1991-01-01

Because of the presence of high cyclic thermal stress, pressure-induced primary stress, and disruption-induced high cyclic primary stress, ratcheting of the first wall poses a serious challenge to the designers of ITER (International Thermonuclear Experimental Reactor). Existing design tools such as the Bree diagram in the ASME Boiler and Pressure Vessels Code, are not directly applicable to ITER, because of important differences in geometry and loading modes. Available alternative models for ratcheting are discussed and new Bree diagrams, that are more relevant for fusion reactor applications, are proposed. 9 refs., 17 figs

Experimental investigation and finite element simulation of laser beam welding induced residual stresses and distortions in thin sheets of AA 6056-T4

International Nuclear Information System (INIS)

Zain-ul-abdein, Muhammad; Nelias, Daniel; Jullien, Jean-Francois; Deloison, Dominique

2010-01-01

Laser beam welding has recently found its application in the fabrication of aircraft structures where fuselage panels, made of thin sheets of AA 6056-T4 (an aluminium alloy), are welded with stiffeners of the same material in a T-joint configuration. The present work simulates laser beam welding induced residual stresses and distortions using industrially employed thermal and mechanical boundary conditions. Various measurements performed on small-scale welded test specimens provide a database of experimental results that serves as a benchmark for qualification of the simulation results. The welding simulation is performed with the commercial finite element software Abaqus and a Fortran programme encoding a conical heat source with Gaussian volumetric distribution of flux. A sequentially coupled temperature-displacement analysis is undertaken to simulate the weld pool geometry, transient temperature and displacement fields. The material is assumed to follow an elasto-plastic law with isotropic hardening behaviour (von Mises plasticity model). A comparison between the experimental and simulation results shows a good agreement. Finally, the residual stress and strain states in a T-joint are predicted.

Analysis of the temporal regression of the QRS widening induced by bupivacaine after Intralipid administration. Study in an experimental porcine model.

Science.gov (United States)

Zaballos, M; Sevilla, R; González, J; Callejo, D; de Diego, C; Almendral, J; Quintela, O; Anadón, M J

2016-01-01

The principal mechanism of cardiac toxicity of bupivacaine relates to the blockade of myocardial sodium channels, which leads to an increase in the QRS duration. Recently, experimental studies suggest that lipid emulsion is effective in reversing bupivacaine cardiac toxicity. We aimed to evaluate the temporal evolution of the QRS widening induced by bupivacaine with the administration of Intralipid. Twelve pigs were anesthetized with intravenous sodium thiopental 5mg kg(-1) and sevoflurane 1 MAC (2.6%). Femoral artery and vein were canalized for invasive monitoring, analysis of blood gases and determination of bupivacaine levels. After instrumentation and monitoring, a bupivacaine bolus of 4-6 mg kg(-1) was administered in order to induce a 150% increase in QRS duration (defined as the toxic point). The pigs were randomized into two groups of six individuals. Intralipid group (IL) received 1.5 mL kg(-1)of IL over one minute, followed by an infusion of 0.25 mL kg min(-1). Control group (C) received the same volume of a saline solution. The electrocardiographic parameters were recorded, and blood samples were taken after bupivacaine and 1, 5, 10 and 30 minutes after Intralipid/saline administration. Bupivacaine (4.33±0.81 mg/kg in IL group and 4.66±1.15 mg/kg in C group) induced similar electrocardiographic changes in both groups; mean maximal percent increase in QRS interval was 184±62% in IL group, and 230±56% in control group (NS). Lipid administration reversed the QRS widening previously impaired by bupivacaine. After ten minutes of the administration of IL, the mean QRS interval decreased to 132±56% vs. 15±76% relative to the maximum widening induced by bupivacaine, in IL and C group, respectively. Intralipid reversed the lengthening of QRS interval induced by the injection of bupivacaine. Time to normalization of electrocardiographic parameters can last more than 10 minutes. While the phenomena of cardiac toxicity persist, resuscitation measures and

MOTIVATION AND PERFORMANCE IN PHYSICAL EDUCATION: AN EXPERIMENTAL TEST

Directory of Open Access Journals (Sweden)

Juan A. Moreno

2010-03-01

Full Text Available The purpose of this study was to analyse, experimentally, the relationships between motivation and performance in a lateral movement test in physical education. The study group consisted of 363 students (227 boys and 136 girls, aged between 12 and 16, who were randomly divided into three groups: an experimental group in which an incremental ability belief was induced, another experimental group in which an entity ability belief was induced, and a control group where there was no intervention. Measurements were made of situational intrinsic motivation, perceived competence in executing the task and performance. The results revealed that the incremental group reported higher scores on the situational intrinsic motivation scale. The entity group demonstrated better performance in the first test attempt than the incremental group but, in the second attempt, the performance was similar in the different groups. Perhaps the initial differences in performance disappeared because the incremental group counted on improving in the second attempt. These results are discussed in relation to the intensity with which the teacher conveys information relating to incremental ability belief of the pupil to increase intrinsic motivation and performance

Cardioprotective effect of mumie (shilajit) on experimentally induced myocardial injury.

Science.gov (United States)

Joukar, Siyavash; Najafipour, Hamid; Dabiri, Shahriar; Sheibani, Mohammad; Sharokhi, Nader

2014-09-01

This study assessed the effects of mumie (shilajit) pre-treatment, a traditional drug which is well known in the ancient medicine of both east and west, on cardiac performance of rats subjected to myocardial injury. Animals were divided into control, M250, and M500 (received mumie at dosages of 250 and 500 mg/kg/day, orally for 7 days, respectively) main groups each consisting of two subgroups-with and without heart injury. On the 6th and 7th days, isoproterenol (ISO) (85 mg/kg i.p.) was injected (s.c.) to half of the animal subgroups to induce myocardial damage. On the 8th day, after hemodynamic parameter recordings, hearts were removed for further evaluation. Mumie pre-treatment had no significant effects on hemodynamic and cardiac indices of normal animals. When the cardiac injury was induced, mumie maintained the ±dp/dt maximum, attenuated the serum cardiac troponin I, and reduced the severity of cardiac lesions. Despite the mild positive effects of mumie on total antioxidant capacity and lipid proxidation index, no significant difference was observed among animal groups. The findings suggest the prominent cardioprotective effect of mumie against destructive effects of ISO. It seems that other mechanisms than reinforcements of antioxidant system are involved in this beneficial effect.

Experimental observation of zinc dialkyl dithiophosphate (ZDDP)-induced iron sulphide formation

Energy Technology Data Exchange (ETDEWEB)

Soltanahmadi, Siavash, E-mail: s.soltanahmadi@leeds.ac.uk [Institute of Functional Surfaces, School of Mechanical Engineering, University of Leeds, LS2 9JT (United Kingdom); Morina, Ardian [Institute of Functional Surfaces, School of Mechanical Engineering, University of Leeds, LS2 9JT (United Kingdom); Eijk, Marcel C.P. van; Nedelcu, Ileana [SKF Engineering and Research Centre, 3430 DT Nieuwegein (Netherlands); Neville, Anne [Institute of Functional Surfaces, School of Mechanical Engineering, University of Leeds, LS2 9JT (United Kingdom)

2017-08-31

Graphical abstract: Chemical analysis of ZDDP-induced tribofilm under severe boundary lubricated regime in nano and micro-meter scales.▪ - Highlights: • A ZDDP-derived locally formed iron-sulphide layer is detected on the steel surface. • The iron-sulphide is a 5–10 nm thin distinct layer at steel-phosphate interface. • Near the surface-crack site the elemental distribution of the tribofilm is altered. • Sulphur concentration is enhanced in the iron-sulphide layer near the cracked-site. • ZDDP elements are detected inside the crack with a greater contribution of sulphur. - Abstract: Zinc dialkyl dithiophosphate (ZDDP) as a well-known anti-wear additive enhances the performance of the lubricant beyond its wear-protection action, through its anti-oxidant and Extreme Pressure (EP) functionality. In spite of over thirty years of research attempting to reveal the mechanism of action of ZDDP, there are still some uncertainties around the exact mechanisms of its action. This is especially the case with the role of sulphide layer formed in the tribofilm and its impact on surface fatigue. Although iron sulphide on the substrate is hypothesised in literature to form as a separate layer, there has been no concrete experimental observation on the distribution of the iron sulphide as a dispersed precipitate, distinct layer at the steel substrate or both. It remains to be clarified whether the iron sulphide layer homogeneously covers the surface or locally forms at the surface. In the current study a cross section of the specimen after experiment was prepared and has been investigated with Transmission Electron Microscopy (TEM) and Energy-Dispersive X-ray (EDX) elemental analysis. A 5–10 nm iron sulphide layer is visualised on the interface as a separate layer underneath the phosphate layer with an altered distribution of tribofilm elements near the crack site. The iron sulphide interface layer is more visible near the crack site where the concentration of the

Experimental observation of zinc dialkyl dithiophosphate (ZDDP)-induced iron sulphide formation

International Nuclear Information System (INIS)

Soltanahmadi, Siavash; Morina, Ardian; Eijk, Marcel C.P. van; Nedelcu, Ileana; Neville, Anne

2017-01-01

Graphical abstract: Chemical analysis of ZDDP-induced tribofilm under severe boundary lubricated regime in nano and micro-meter scales.▪ - Highlights: • A ZDDP-derived locally formed iron-sulphide layer is detected on the steel surface. • The iron-sulphide is a 5–10 nm thin distinct layer at steel-phosphate interface. • Near the surface-crack site the elemental distribution of the tribofilm is altered. • Sulphur concentration is enhanced in the iron-sulphide layer near the cracked-site. • ZDDP elements are detected inside the crack with a greater contribution of sulphur. - Abstract: Zinc dialkyl dithiophosphate (ZDDP) as a well-known anti-wear additive enhances the performance of the lubricant beyond its wear-protection action, through its anti-oxidant and Extreme Pressure (EP) functionality. In spite of over thirty years of research attempting to reveal the mechanism of action of ZDDP, there are still some uncertainties around the exact mechanisms of its action. This is especially the case with the role of sulphide layer formed in the tribofilm and its impact on surface fatigue. Although iron sulphide on the substrate is hypothesised in literature to form as a separate layer, there has been no concrete experimental observation on the distribution of the iron sulphide as a dispersed precipitate, distinct layer at the steel substrate or both. It remains to be clarified whether the iron sulphide layer homogeneously covers the surface or locally forms at the surface. In the current study a cross section of the specimen after experiment was prepared and has been investigated with Transmission Electron Microscopy (TEM) and Energy-Dispersive X-ray (EDX) elemental analysis. A 5–10 nm iron sulphide layer is visualised on the interface as a separate layer underneath the phosphate layer with an altered distribution of tribofilm elements near the crack site. The iron sulphide interface layer is more visible near the crack site where the concentration of the

Effects of morphine on the expression of cytokines and inflammatory mediators in a rabbit model of endotoxin-induced experimental uveitis

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Kethye P. Ortencio

2015-12-01

Full Text Available ABSTRACT Purpose: To evaluate the effects of 1% morphine instillation on clinical parameters, aqueous humor turbidity, and expression levels of tumor necrosis factor alpha (TNF-α, interleukin-1 beta (IL-1beta, prostaglandin E2 (PGE2, and myeloperoxidase (MPO in rabbits with endotoxin-induced experimental uveitis. Methods: Twenty four New Zealand white rabbits were divided into four groups (n=6 each: control (CG, morphine (MG, naloxone (NG, and morphine-naloxone (MNG groups. Under dissociative anesthesia, 0.1 mL of solution containing 0.2 µg of lipopolysaccharide (LPS endotoxin from the Salmonella typhimurium cell wall was injected in the vitreous chamber. Clinical evaluations (conjunctical hyperemia, chemosis blepharospasm, and ocular discharge and laser flaremetry were performed before (baseline, and 10 and 20 hours after induction of uveitis. Rabbits were subsequently euthanized and eyes were enucleated to quantify expression levels of TNF-α, IL-1 beta, PGE2, and MPO. Results: No significant differences in clinical parameters and flare values were observed between the study groups. TNF-α and IL-1 beta levels increased significantly in the CG, MG, NG, and MNG groups compared to baseline (P0.05. Conclusions: Morphine has no effect on clinical parameters, flare, or expression levels of inflammatory mediators in a rabbit model of uveitis induced by intravitreal injection of LPS.

Heavy-ion-induced, gate-rupture in power MOSFETs

International Nuclear Information System (INIS)

Fischer, T.A.

1987-01-01

A new, heavy-ion-induced, burnout mechanism has been experimentally observed in power metal-oxide-semiconductor field-effect transistors (MOSFETs). This mechanism occurs when a heavy, charged particle passes through the gate oxide region of n- or p-channel devices having sufficient gate-to-source or gate-to-drain bias. The gate-rupture leads to significant permanent degradation of the device. A proposed failure mechanism is discussed and experimentally verified. In addition, the absolute immunity of p-channel devices to heavy-ion-induced, semiconductor burnout is demonstrated and discussed along with new, non-destructive, burnout testing methods

Pain and executive functions: A unique relationship between Stroop task and experimentally induced pain

NARCIS (Netherlands)

Bjekic, J.; Zivanovic, M.; Puric, D.; Oosterman, J.M.; Filipovic, S.R.

2018-01-01

There is a growing body of evidence that a higher level of cognitive inhibition is associated with lower experimental pain sensitivity. However, a systematic examination of the association between executive functions, which include not only inhibition but also updating and shifting, and experimental

Drug-induced Hypothermia by 5HT1A Agonists Provide Neuroprotection in Experimental Stroke

DEFF Research Database (Denmark)

Johansen, Flemming Fryd; Hasseldam, Henrik; Nybro Smith, Matthias

2014-01-01

BACKGROUND: Drug-induced hypothermia reduces brain damage in animal stroke models and is an undiscovered potential in human stroke treatment. We studied hypothermia induced by the serotonergic agonists S14671 (1-[2-(2-thenoylamino)ethyl]-4[1-(7- methoxynaphtyl)]piperazine) and ipsapirone in a rat...... therapeutic hypothermia....

Effects of experimentally induced hyperthyroidism on central hypothalamic-pituitary-adrenal axis function in rats: in vitro and in situ studies.

Science.gov (United States)

Johnson, Elizabeth O; Calogero, Aldo E; Konstandi, Maria; Kamilaris, Themis C; La Vignera, Sandro; Vignera, Sandro La; Chrousos, George P

2013-06-01

Hyperthyroidism is associated with hypercorticosteronemia, although the locus that is principally responsible for the hypercorticosteronism remains unclear. The purpose of this study was to assess the effects of hyperthyroidism on the functional integrity of the hypothalamic-pituitary-adrenal (HPA) axis, to identify the locus in the HPA axis that is principally affected, and address the time-dependent effects of alterations in thyroid status. The functional integrity of each component of the HPA axis was examined in vitro and in situ in sham-thyroidectomized male Sprague-Dawley rats given placebo or in thyroidectomized rats given pharmacological dose (50 μg) of thyroxin for 7 or 60 days. Basal plasma corticosterone and corticosterone binding globulin (CBG) concentrations were significantly increased in short- and long-term hyperthyroid rats, and by 60 days. Basal plasma ACTH levels were similar to controls. Both hypothalamic CRH content and the magnitude of KCL- and arginine vasopressin (AVP)-induced CRH release from hypothalamic culture were increased in long-term hyperthyroid rats. There was a significant increase in the content of both ACTH and β-endorphin in the anterior pituitaries of both short- and long-term hyperthyroid animals. Short-term hyperthyroid rats showed a significant increase in basal POMC mRNA expression in the anterior pituitary, and chronically hyperthyroid animals showed increased stress-induced POMC mRNA expression. Adrenal cultures taken from short-term hyperthyroid rats responded to exogenous ACTH with an exaggerated corticosterone response, while those taken from 60-day hyperthyroid animals showed responses similar to controls. The findings show that hyperthyroidism is associated with hypercorticosteronemia and HPA axis dysfunction that becomes more pronounced as the duration of hyperthyroidism increases. The evidence suggests that experimentally induced hyperthyroidism is associated with central hyperactivity of the HPA axis.

Exogenous hydrogen sulfide (H2S protects alveolar growth in experimental O2-induced neonatal lung injury.

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Arul Vadivel

Full Text Available Bronchopulmonary dysplasia (BPD, the chronic lung disease of prematurity, remains a major health problem. BPD is characterized by impaired alveolar development and complicated by pulmonary hypertension (PHT. Currently there is no specific treatment for BPD. Hydrogen sulfide (H2S, carbon monoxide and nitric oxide (NO, belong to a class of endogenously synthesized gaseous molecules referred to as gasotransmitters. While inhaled NO is already used for the treatment of neonatal PHT and currently tested for the prevention of BPD, H2S has until recently been regarded exclusively as a toxic gas. Recent evidence suggests that endogenous H2S exerts beneficial biological effects, including cytoprotection and vasodilatation. We hypothesized that H2S preserves normal alveolar development and prevents PHT in experimental BPD.We took advantage of a recently described slow-releasing H2S donor, GYY4137 (morpholin-4-ium-4-methoxyphenyl(morpholino phosphinodithioate to study its lung protective potential in vitro and in vivo.In vitro, GYY4137 promoted capillary-like network formation, viability and reduced reactive oxygen species in hyperoxia-exposed human pulmonary artery endothelial cells. GYY4137 also protected mitochondrial function in alveolar epithelial cells. In vivo, GYY4137 preserved and restored normal alveolar growth in rat pups exposed from birth for 2 weeks to hyperoxia. GYY4137 also attenuated PHT as determined by improved pulmonary arterial acceleration time on echo-Doppler, pulmonary artery remodeling and right ventricular hypertrophy. GYY4137 also prevented pulmonary artery smooth muscle cell proliferation.H2S protects from impaired alveolar growth and PHT in experimental O2-induced lung injury. H2S warrants further investigation as a new therapeutic target for alveolar damage and PHT.

Macrophages and Uveitis in Experimental Animal Models

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Salvador Mérida

2015-01-01

Full Text Available Resident and infiltrated macrophages play relevant roles in uveitis as effectors of innate immunity and inductors of acquired immunity. They are major effectors of tissue damage in uveitis and are also considered to be potent antigen-presenting cells. In the last few years, experimental animal models of uveitis have enabled us to enhance our understanding of the leading role of macrophages in eye inflammation processes, including macrophage polarization in experimental autoimmune uveoretinitis and the major role of Toll-like receptor 4 in endotoxin-induced uveitis. This improved knowledge should guide advantageous iterative research to establish mechanisms and possible therapeutic targets for human uveitis resolution.

Effectiveness of Bioactive Food Components in Experimental Colon Carcinogenesis

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Emília Hijová

2009-01-01

Full Text Available The aim of the present study was the evaluation of possible protective effects of selected bioactive food components in experimental N,N-dimethylhydrazine (DMH-induced colon carcinogenesis. Wistar albino rats (n = 92 were fed a high fat diet or conventional laboratory diet. Two weeks after the beginning of the trial, DMH injections were given to six groups of rats at the dose of 20 mg/kg b.w. twice weekly. The activity of bacterial enzymes in faeces and serum bile acid concentrations were determined. High fat diet, DMH injections, and their combination significantly increased the activies of β-galactosidase, β-glucuronidase, and α-glucosidase (p p < 0.001, as well as the bile acid concentration compared to the group at the highest risk. The protective effects of selected bioactive food components in experimentally induced colon carcinogenesis allow for their possible use in cancer prevention or treatment.

Induced-hypercholesterolemia as a probable cause of alterations in ...

African Journals Online (AJOL)

Methods: The telemetry technique was used to investigate the cardiovascular dysfunctions in induced hypercholesterolemia in Wistar Kyoto (WKY) rats. Methods for this investigation include: inducing hypercholesterolemic condition in Wistar Kyoto rats through diet; measuring the blood cholesterol levels of the experimental ...

Overlapping molecular pathological themes link Charcot-Marie-Tooth neuropathies and hereditary spastic paraplegias.

Science.gov (United States)

Timmerman, Vincent; Clowes, Virginia E; Reid, Evan

2013-08-01

In this review we focus on Charcot-Marie-Tooth (CMT) neuropathies and hereditary spastic paraplegias (HSPs). Although these diseases differ in whether they primarily affect the peripheral or central nervous system, both are genetically determined, progressive, long axonopathies that affect motor and sensory pathways. This commonality suggests that there might be similarities in the molecular pathology underlying these conditions, and here we compare the molecular genetics and cellular pathology of the two groups. Copyright © 2012 Elsevier Inc. All rights reserved.

Ansiedade experimental humana Human experimental anxiety

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Frederico Guilherme Graeff

2007-01-01

Full Text Available CONTEXTO: A ansiedade experimental no ser humano constitui-se em ponte entre os modelos animais e os ensaios clínicos. OBJETIVO: Este artigo focaliza métodos químicos e psicológicos utilizados para provocar ansiedade experimental em seres humanos. MÉTODOS: Realizou-se revisão seletiva da literatura. RESULTADOS: Os desafios farmacológicos têm sido usados principalmente para induzir ataques de pânico em pacientes com transtorno de pânico, os quais são mais sensíveis a eles que indivíduos normais ou pacientes portadores de outros transtornos psiquiátricos. Uma das mais importantes contribuições deste método é a de ter mostrado que os agentes panicogênicos mais seletivos, como o lactato ou a inalação de CO2, não ativam o eixo hormonal do estresse. Entre os métodos psicológicos, destacam-se o condicionamento de respostas elétricas da condutância da pele, cujo perfil farmacológico se aproxima daquele do transtorno de ansiedade generalizada, e o teste da simulação do falar em público, cuja farmacologia é semelhante à do transtorno de pânico. CONCLUSÕES: Tais resultados salientam a diferença entre a neurobiologia da ansiedade e a do pânico.BACKGROUND: Human experimental anxiety methods bridge the gap between animal models and clinical assays. OBJECTIVE: This article is focused on chemical and psychological procedures used to generate experimental anxiety in human beings. METHODS: A selective review of the literature has been carried out. RESULTS: Pharmacological challenges have been mainly used to induce panic attacks in panic disorder patients, who are more susceptible than normal individuals or patients with other psychiatric disorders. One of the most important contributions of this method is to have shown that the most selective panicogenic agents, such as lactate or CO2 inhalation, do not activate the hormonal stress axis. Among the psychological methods stand the conditioning of the electrical skin conductance

An experimental facility for microwave induced plasma processing of materials

International Nuclear Information System (INIS)

Patil, D.S.; Ramachandran, K.; Bhide, A.L.; Venkatramani, N.

1997-01-01

Microwave induced plasma processing offers many advantages over conventional processes. However this technology is in the development stage. This report gives a detailed information about a microwave plasma processing facility (2.45 GHz, 700 W) set up in the Laser and Plasma Technology Division. The equipment details and the results obtained on deposition of diamond like carbon (DLC) thin films and surface modification of polymer PET (polyethylene terephthalate) using this facility are given in this report. (author)

Alleviating effects of morin against experimentally-induced diabetic osteopenia

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Abuohashish Hatem M

2013-02-01

Full Text Available Abstract Background Plant flavonoids are emerging as potent therapeutic drugs effective against a wide range of aging diseases particularly bone metabolic disorders. Morin (3,5,7,20,40-pentahydroxyflavone, a member of flavonols, is an important bioactive compound by interacting with nucleic acids, enzymes and protein. The present study was designed to investigate the putative beneficial effect of morin on diabetic osteopenia in rats. Methods Streptozotocin (STZ-induced diabetic model was used by considering 300 mg/dl fasting glucose level as diabetic. Morin (15 and 30 mg/kg was treated for five consecutive weeks to diabetic rats. Serum levels of glucose, insulin, deoxypyridinoline cross links (DPD, osteocalcin (OC, bone specific alkaline phosphatase (BALP, telopeptides of collagen type I (CTX, interleukin 1 beta (IL-1β, interleukin 6 (IL-6, tumor necrosis factor alpha (TNF-α, thiobarbituric acid reactive substance (TBARS and reduced glutathione (GSH were estimated. Femoral bones were taken for micro CT scan to measure trabecular bone mineral density (BMD and other morphometric parameters. Results Significant bone loss was documented as the level of bone turnover parameters including DPD, OC, BALP and CTX were increased in serum of diabetic rats. Morin treatment significantly attenuated these elevated levels. Bone micro-CT scan of diabetic rats showed a significant impairment in trabecular bone microarchitecture, density and other morphometric parameters. These impairments were significantly ameliorated by morin administration. Serum levels of glucose, TBARS, IL-1β, IL-6 and TNF-α were significantly elevated, while the level of insulin and GSH was decreased in diabetic rats. These serum changes in diabetic rats were bring back to normal values after 5 weeks morin treatment. Conclusion These findings revealed the protective effect of morin against diabetic induced osteopenia. We believed that this effect is through its both the anti

Ventilator and viral induced inflammation

NARCIS (Netherlands)

Hennus, M.P.

2013-01-01

This thesis expands current knowledge on ventilator induced lung injury and provides insights on the immunological effects of mechanical ventilation during viral respiratory infections. The experimental studies in the first part of this thesis improve our understanding of how mechanical ventilation

Effect of scoparia dulcis (Sweet Broomweed) plant extract on plasma antioxidants in streptozotocin-induced experimental diabetes in male albino Wistar rats.

Science.gov (United States)

Pari, L; Latha, M

2004-07-01

Clinical research has confirmed the efficacy of several plants in the modulation of oxidative stress associated with diabetes mellitus. Scoparia dulcis plant extract is tried for prevention and treatment of diabetes mellitus induced experimentally by streptozotocin injection. A single dose of streptozotocin (45 mg/kg body weight) produced decrease in insulin, hyperglycemia, increased lipid peroxidation (Thiobarbituric reactive substances and lipid hydroperoxides) and decreased antioxidant levels (vitamin C, vitamin E, reduced glutathione, ceruloplasmin). Oral administration of an aqueous extract of Scoparia dulcis plant (200 mg/kg body weight) for 6 weeks to diabetic rats significantly increased the plasma insulin and plasma antioxidants and significantly decreased lipid peroxidation. The effect of Scoparia dulcis plant extract at 200 mg/kg body weight was better than that of glibenclamide, a reference drug.

Contractile profile of esophageal and gastric fundus strips in experimental doxorubicin-induced esophageal atresia

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F.A. Capeto

2015-05-01

Full Text Available Esophageal atresia (EA is characterized by esophageal and gastric motility changes secondary to developmental and postsurgical damage. This study evaluated the in vitro contractile profile of the distal esophagus and gastric fundus in an experimental model of EA induced by doxorubicin (DOXO. Wistar pregnant rats received DOXO 2.2 mg/kg on the 8th and 9th gestational days. On day 21.5, fetuses were collected, sacrificed, and divided into groups: control, DOXO without EA (DOXO-EA, and DOXO with EA (DOXO+EA. Strips from the distal esophagus and gastric fundus were mounted on a wire myograph and isolated organ-bath system, respectively, and subjected to increasing concentrations of carbamylcholine chloride (carbachol, CCh. The isolated esophagus was also stimulated with increasing concentrations of KCl. In esophagus, the concentration-effect curves were reduced in response to CCh in the DOXO+EA and DOXO-EA groups compared to the control group (P0.05. In response to KCl, the distal esophagus samples in the three groups were not statistically different with regard to Emax or EC50 values (P>0.05. No significant difference was noted for EC50 or Emax values in fundic strips stimulated with CCh (P>0.05. In conclusion, exposure of dams to DOXO during gestation inhibited the contractile behavior of esophageal strips from offspring in response to CCh but not KCl, regardless of EA induction. The gastric fundus of DOXO-exposed offspring did not have altered contractile responsiveness to cholinergic stimulation.

Epitope-Specific Tolerance Modes Differentially Specify Susceptibility to Proteolipid Protein-Induced Experimental Autoimmune Encephalomyelitis

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Lei Wang

2017-11-01

Full Text Available Immunization with myelin components can elicit experimental autoimmune encephalomyelitis (EAE. EAE susceptibility varies between mouse strains, depending on the antigen employed. BL/6 mice are largely resistant to EAE induction with proteolipid protein (PLP, probably a reflection of antigen-specific tolerance. However, the extent and mechanism(s of tolerance to PLP remain unclear. Here, we identified three PLP epitopes in PLP-deficient BL/6 mice. PLP-sufficient mice did not respond against two of these, whereas tolerance was “leaky” for an epitope with weak predicted MHCII binding, and only this epitope was encephalitogenic. In TCR transgenic mice, the “EAE-susceptibility-associated” epitope was “ignored” by specific CD4 T cells, whereas the “resistance-associated” epitope induced clonal deletion and Treg induction in the thymus. Central tolerance was autoimmune regulator dependent and required expression and presentation of PLP by thymic epithelial cells (TECs. TEC-specific ablation of PLP revealed that peripheral tolerance, mediated by dendritic cells through recessive tolerance mechanisms (deletion and anergy, could largely compensate for a lack of central tolerance. However, adoptive EAE was exacerbated in mice lacking PLP in TECs, pointing toward a non-redundant role of the thymus in dominant tolerance to PLP. Our findings reveal multiple layers of tolerance to a central nervous system autoantigen that vary among epitopes and thereby specify disease susceptibility. Understanding how different modalities of tolerance apply to distinct T cell epitopes of a target in autoimmunity has implications for antigen-specific strategies to therapeutically interfere with unwanted immune reactions against self.

Altered monocyte function in experimental preeclampsia in the rat

NARCIS (Netherlands)

Faas, Marijke M.; Broekema, Martine; Moes, Henk; van der Schaaf, Gerda; Heineman, Maas Jan; de Vos, Paul

2004-01-01

OBJECTIVES: In the present study, we evaluated functional activity of monocytes in experimental preeclampsia induced by low-dose endotoxin infusion. STUDY DESIGN: Pregnant (n = 12) and cyclic rats (n = 12) were equipped with a permanent jugular vein cannula and infused with either low-dose endotoxin

Anti-inflammatory activity of methyl palmitate and ethyl palmitate in different experimental rat models

Energy Technology Data Exchange (ETDEWEB)

Saeed, Noha M. [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Egyptian Russian University, Cairo (Egypt); El-Demerdash, Ebtehal [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo (Egypt); Abdel-Rahman, Hanaa M. [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Egyptian Russian University, Cairo (Egypt); Algandaby, Mardi M. [Department of Biology (Botany), Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); Al-Abbasi, Fahad A. [Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); Abdel-Naim, Ashraf B., E-mail: abnaim@pharma.asu.edu.eg [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo (Egypt)

2012-10-01

Methyl palmitate (MP) and ethyl palmitate (EP) are naturally occurring fatty acid esters reported as inflammatory cell inhibitors. In the current study, the potential anti-inflammatory activity of MP and EP was evaluated in different experimental rat models. Results showed that MP and EP caused reduction of carrageenan-induced rat paw edema in addition to diminishing prostaglandin E2 (PGE2) level in the inflammatory exudates. In lipopolysaccharide (LPS)-induced endotoxemia in rats, MP and EP reduced plasma levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). MP and EP decreased NF-κB expression in liver and lung tissues and ameliorated histopathological changes caused by LPS. Topical application of MP and EP reduced ear edema induced by croton oil in rats. In the same animal model, MP and EP reduced neutrophil infiltration, as indicated by decreased myeloperoxidase (MPO) activity. In conclusion, this study demonstrates the effectiveness of MP and EP in combating inflammation in several experimental models. -- Highlights: ► Efficacy of MP and EP in combating inflammation was displayed in several models. ► MP and EP reduced carrageenan-induced rat paw edema and prostaglandin E2 level. ► MP and EP decreased TNF-α and IL-6 levels in experimental endotoxemia. ► MP and EP reduced NF-κB expression and histological changes in rat liver and lung. ► MP and EP reduced croton oil-induced ear edema and neutrophil infiltration.

Experimental and numerical investigations of a hydrogen-assisted laser-induced materials transfer procedure

International Nuclear Information System (INIS)

Toet, D.; Smith, P. M.; Sigmon, T. W.; Thompson, M. O.

2000-01-01

We present investigations of the mechanisms of a laser-induced transfer technique, which can be used for the spatially selective deposition of materials such as Si. This transfer is effected by irradiating the backside of a hydrogenated amorphous silicon film, deposited on a transparent substrate with an excimer laser pulse. The resulting release and accumulation of hydrogen at the film/substrate interface propels the silicon onto an adjacent receptor wafer. Time-resolved infrared transmission measurements indicate that the amorphous film is melted by the laser pulse and breaks into droplets during ejection. These droplets travel towards the receptor substrate and coalesce upon arrival. The transfer velocity increases as a function of fluence, the rate of increase dropping noticeably around the full melt threshold of the film. At this fluence, the transfer velocity reaches values of around 1000 m/s for typical films. Atomic force microscopy reveals that films transferred below the full melt threshold only partially cover the receptor substrate, while uniform, well-adhering films, which can be smoothed by subsequent laser irradiation, are obtained above it. Transfer of hydrogen-free Si films, on the other hand, does not occur until much higher fluences. The dynamics of the process have been simulated using a semiquantitative numerical model. In this model, hydrogen released from the melt front is instantaneously accumulated at the interface with an initial kinetic energy given by the melting temperature of Si and the enthalpy of solution. The resulting pressure accelerates the Si film, the dynamics of which are modeled using Newtonian mechanics, and the gas cools adiabatically as its kinetic energy is converted to the film's momentum. The results of the calculations are in good agreement with the experimental data. (c) 2000 American Institute of Physics

Observation of electromagnetically induced Talbot effect in an atomic system

Science.gov (United States)

Zhang, Zhaoyang; Liu, Xing; Zhang, Dan; Sheng, Jiteng; Zhang, Yiqi; Zhang, Yanpeng; Xiao, Min

2018-01-01

The electromagnetically induced Talbot effect (EITE) resulting from the repeated self-reconstruction of a spatially intensity-modulated probe field is experimentally demonstrated in a three-level atomic configuration. The probe beam is launched into an optically induced lattice (established by the interference of two coupling fields) inside a rubidium vapor cell and is diffracted by the electromagnetically induced grating that was formed. The diffraction pattern repeats itself at the planes of integer multiple Talbot lengths. In addition, a fractional EITE is also investigated. The experimental observations agree well with the theoretical predictions. This investigation may potentially pave the way for studying the nonlinear and quantum dynamical features that have been predicted for established periodic optical systems.

Experimental investigation on in-plane/out-of-plane vortex-induced vibrations of curved cylinder in parallel and perpendicular flows

Science.gov (United States)

Srinil, Narakorn; Ma, Bowen; Zhang, Licong

2018-05-01

This study is motivated by an industrial need to better understand the vortex-induced vibration (VIV) of a curved structure subject to current flows with varying directions whose data for model calibration and validation are lacking. In this paper, new experimental investigations on the two-degree-of-freedom in-plane/out-of-plane VIV of a rigid curved circular cylinder immersed in steady and uniform free-stream flows are presented. The principal objective is to examine how the approaching flow direction versus the cylinder curvature plane affects cross-flow and in-line VIV and the associated hydrodynamic properties. This is achieved by testing the curved cylinder in 3 different flow orientations comprising the parallel flows aligned with the curvature vertical plane in convex and concave configurations, and the flows perpendicular to the curvature plane. The case of varying flow velocities in a subcritical flow range with a maximum Reynolds number of about 50,000 is considered for the curved cylinder with a low mass ratio and damping ratio. Experimental results are presented and discussed in terms of the cylinder response amplitudes, inclination angles, mean displacements, motion trajectories, oscillation frequencies, hydrodynamic forces, relative phases, fluid excitation and added inertia coefficients. Comparisons with other experimental results of curved and straight cylinder VIV are also presented. The experiments highlight the important effects of cylinder curvature versus flow orientation on the combined cross-flow/in-line VIV. The maximum (minimum) responses occur in the perpendicular (convex) flow case whereas the extended lower-branch responses occur in the concave flow case. For perpendicular flows, some meaningful features are observed, including the appearances of cross-flow mean displacements and asymmetric eight-shaped motion trajectories due to multiple 2:1:1 resonances where two out-of-plane and one in-plane dominant frequencies are simultaneously

Experimental tests of induced spatial incoherence using short laser wavelength

International Nuclear Information System (INIS)

Obenschain, S.P.; Grun, J.; Herbst, M.J.

1986-01-01

The authors have developed a laser beam smoothing technique called induced spatial incoherence (ISI), which can produce the highly uniform focal profiles required for direct-drive laser fusion. Uniform well-controlled focal profiles are required to obtain the highly symmetric pellet implosions needed for high-energy gain. In recent experiments, the authors' tested the effects of ISI on high-power laser-target interaction. With short laser wavelength, the coupling physics dramatically improved over that obtained with an ordinary laser beam

Definition of airflow rate induced by polifractional materials

Science.gov (United States)

Popov, E. N.

2018-03-01

This paper deals with further analysis of a probabilistic and statistical approach to determine the aerodynamic drag coefficient of particles in a flow of free-falling polifractional material. It also describes the experimental assembly enabling one to determine airflow rate induced by polifractional material and provides comparison of analytical calculations with experimental data.

Effect of amiloride on experimental acid-induced heartburn in non-erosive reflux disease.

Science.gov (United States)

Bulsiewicz, William J; Shaheen, Nicholas J; Hansen, Mark B; Pruitt, Amy; Orlando, Roy C

2013-07-01

Acid-sensing ion channels (ASICs) are esophageal nociceptors that are candidates to mediate heartburn in non-erosive reflux disease (NERD). Amiloride, a diuretic, is known to inhibit ASICs. For this reason, we sought a role for ASICs in mediating heartburn by determining whether amiloride could block heartburn in NERD induced by esophageal acid perfusion. In a randomized double-blind crossover study, we perfused the esophagus with amiloride or (saline) placebo prior to eliciting acid-induced heartburn in patients with a history of proton pump inhibitor-responsive NERD. Those with NERD and positive modified Bernstein test were randomized to perfusion with amiloride, 1 mmol/l, or placebo for 5 min, followed by repeat acid-perfusion. Heartburn severity and time to onset was measured and the process repeated following crossover to the alternative agent. 14 subjects completed the study. Amiloride did not reduce the frequency (100 vs. 100 %) or severity of acid-induced heartburn (Mean 2.50 ± SEM 0.33 vs. 2.64 ± 0.45), respectively. There was a trend towards longer time to onset of heartburn for amiloride versus placebo (Mean 2.93 ± SEM 0.3 vs. 2.36 ± 0.29 min, respectively), though these differences did not reach statistical significance (p > 0.05). Amiloride had no significant effect on acid-induced heartburn frequency or severity in NERD, although there was a trend towards prolonged time to onset of symptoms.

Inducible nitric oxide synthase mediates bone loss in ovariectomized mice.

NARCIS (Netherlands)

Cuzzocrea, S.; Mazzon, E.; Dugo, L.; Genovese, T.; Paola, R. Di; Ruggeri, Z.; Vegeto, E.; Caputi, A.P.; Loo, F.A.J. van de; Puzzolo, D.; Maggi, A.

2003-01-01

Several clinical studies have shown that bone loss may be attributed to osteoclast recruitment induced by mediators of inflammation. In different experimental paradigms we have recently demonstrated that estrogen exhibits antiinflammatory activity by preventing the induction of inducible nitric

Experimental Bacterial Endocarditis in the Opossum (Didelphis virginiana)

Science.gov (United States)

Sherwood, B. F.; Rowlands, D. T.; Vakilzadeh, J.; LeMay, J. C.

1971-01-01

It was possible to induce bacterial endocarditis in opossums with single intravenous injections of Streptococcus viridans or Staphylococcus aureus. Fiftyeight percent of those animals given Streptococcus viridans developed bacterial endocarditis in which most of the lesions were on the left side of the heart. The experimentally induced streptococcal disease was similar to that which may occur spontaneously in opossums, both with respect to the distribution and structure of the vegetations. Single injections of Staphylococcus aureus resulted in endocarditis in 100% of the test animals. These lesions differed from those due to streptococci by having a relatively high frequency of right- as well as left-sided valvular disease and by being somewhat smaller than those due to streptococci.Endocarditis could not be successfully induced with injection of three different fungi. PMID:5133514

Effect of zinc treatment on intestinal motility in experimentally ...

African Journals Online (AJOL)

Effect of zinc treatment on intestinal motility in experimentally induced diarrhea in rats. ... Zinc supplementation is a critical new intervention for treating diarrheal episodes in children. Recent studies suggest that administration of zinc along with new low osmolarity oral rehydration solutions / salts (ORS) can reduce the ...

Steered molecular dynamics simulations of a bacterial type IV pilus reveal characteristics of an experimentally-observed, force-induced conformational transition

Science.gov (United States)

Baker, Joseph; Biais, Nicolas; Tama, Florence

2011-10-01

Type IV pili (T4P) are long, filamentous structures that emanate from the cellular surface of many infectious bacteria. They are built from a 158 amino acid long subunit called pilin. T4P can grow to many micrometers in length, and can withstand large tension forces. During the infection process, pili attach themselves to host cells, and therefore naturally find themselves under tension. We investigated the response of a T4 pilus to a pulling force using the method of steered molecular dynamics (SMD) simulation. Our simulations expose to the external environment an amino acid sequence initially hidden in the native filament, in agreement with experimental data. Therefore, our simulations might be probing the initial stage of the transition to a force-induced conformation of the T4 pilus. Additional exposed amino acid sequences that might be useful targets for drugs designed to mitigate bacterial infection were also predicted.

Endotoxemia and the host systemic response during experimental gingivitis

Science.gov (United States)

Wahaidi, Vivian Y.; Kowolik, Michael J.; Eckert, George J.; Galli, Dominique M.

2011-01-01

Aim To assess endotoxemia episodes and subsequent changes in serum inflammatory biomarkers using the experimental gingivitis model Materials and Methods Data from 50 healthy black and white adult males and females were compared for serum concentrations of endotoxin, and serum biomarkers [neutrophil oxidative activity, interleukin (IL)-1β, IL-6, IL-8, C-reactive protein, and fibrinogen] at baseline, at 3 weeks of experimental gingivitis, and after 2 weeks of recovery. Means were compared using repeated measures ANOVA. Results Endotoxemia was reported in 56% of the serum samples at three weeks of induced gingivitis. At two weeks of recovery, endotoxin levels decreased to levels similar to those reported at baseline. Neutrophil oxidative activity increased significantly following three weeks of gingivitis versus baseline (pgingivitis was associated with endotoxemia and hyperactivity of circulating neutrophils, but not with changes in systemic levels of cytokines and acute phase proteins. This may be attributed to the mild nature and the short duration of the induced gingivitis. PMID:21320151

Experimental reproduction of necrotic enteritis in chickens: a review.

Science.gov (United States)

Prescott, John F; Smyth, Joan A; Shojadoost, Bahram; Vince, Andrew

2016-06-01

This review discusses key factors important in successful experimental reproduction of necrotic enteritis (NE) in chickens, and how these factors can be adjusted to affect the severity of the lesions induced. The critical bacterial factor is the need to use virulent, netB-positive, strains of Clostridium perfringens; disease severity can be enhanced by using netB-positive C. perfringens strains that are also tpeL-positive, by the use of young rather than old broth cultures, and by the number of days of inoculation and the number of bacteria used. Use of cereals rich in non-starch polysaccharides can enhance disease, as does use of animal proteins. Administration of coccidia, including coccidial vaccines, combined with netB-positive C. perfringens, increases the severity of experimentally-induced NE. Dietary manipulation may be less important in coccidia-based models since the latter are so effective. Disease scoring systems and welfare considerations are discussed.

Ameliorative potential of gemfibrozil and silymarin on experimentally induced nephrotoxicity in rats

Directory of Open Access Journals (Sweden)

A.M. Kabel

2013-12-01

Conclusion: The combination of gemfibrozil and silymarin has protective effects against cisplatin-induced nephrotoxicity in rats better than each of these drugs alone due to anti-inflammatory and antioxidant properties of the used drugs.

Experimental and theoretical investigation of the effect of SiO2 content in gate dielectrics on work function shift induced by nanoscale capping layers

KAUST Repository

Caraveo-Frescas, J. A.; Wang, H.; Schwingenschlö gl, Udo; Alshareef, Husam N.

2012-01-01

The impact of SiO2 content in ultrathin gate dielectrics on the magnitude of the effective work function (EWF) shift induced by nanoscale capping layers has been investigated experimentally and theoretically. The magnitude of the effective work function shift for four different capping layers (AlN, Al2O3, La2O3, and Gd2O3) is measured as a function of SiO2 content in the gate dielectric. A nearly linear increase of this shift with SiO2 content is observed for all capping layers. The origin of this dependence is explained using density functional theory simulations.

Experimental and theoretical investigation of the effect of SiO2 content in gate dielectrics on work function shift induced by nanoscale capping layers

KAUST Repository

Caraveo-Frescas, J. A.

2012-09-10

The impact of SiO2 content in ultrathin gate dielectrics on the magnitude of the effective work function (EWF) shift induced by nanoscale capping layers has been investigated experimentally and theoretically. The magnitude of the effective work function shift for four different capping layers (AlN, Al2O3, La2O3, and Gd2O3) is measured as a function of SiO2 content in the gate dielectric. A nearly linear increase of this shift with SiO2 content is observed for all capping layers. The origin of this dependence is explained using density functional theory simulations.

Experimental Study of the Lead Tungstate Scintillator Proton-Induced Damage and Recovery

CERN Document Server

Auffray, Etiennette; Singovski , A

2011-01-01

Lead tungstate (PbWO4, or PWO) scintillating crystals are used by two of the four experiments at the Large Hadron Collider (LHC): 75848 in CMS and 17920 in ALICE. For the CMS electromagnetic calorimeter, one of the most important crystal properties is its radiation hardness. With the increase of luminosity, the radiation level will increase drastically, particularly in the high pseudorapidity regions of the calorimeter. Beside the effects of color-centre formation caused by gamma-radiation, additional measurable effect originated by hadron irradiation could appear, which will further deteriorate the optical transmission of the crystals and therefore their efficiency. In this paper, we will present results of the proton-induced damage in PWO and a study of optical transmission recovery at different temperatures and under different light-induced "bleaching" conditions for proton-irradiated crystals.

Combined computational and experimental study of Ar beam induced defect formation in graphite

International Nuclear Information System (INIS)

Pregler, Sharon K.; Hayakawa, Tetsuichiro; Yasumatsu, Hisato; Kondow, Tamotsu; Sinnott, Susan B.

2007-01-01

Irradiation of graphite, commonly used in nuclear power plants, is known to produce structural damage. Here, experimental and computational methods are used to study defect formation in graphite during Ar irradiation at incident energies of 50 eV. The experimental samples are analyzed with scanning tunneling microscopy to quantify the size distribution of the defects that form. The computational approach is classical molecular dynamic simulations that illustrate the mechanisms by which the defects are produced. The results indicate that defects in graphite grow in concentrated areas and are nucleated by the presence of existing defects

SPATIAL MEMORY IMPAIRMENT AND HIPPOCAMPAL CELL LOSS INDUCED BY OKADAIC ACID (EXPERIMENTAL STUDY).

Science.gov (United States)

Chighladze, M; Dashniani, M; Beselia, G; Kruashvili, L; Naneishvili, T

2016-01-01

In the present study, we evaluated and compared effect of intracerebroventricular (ICV) and intrahippocampal bilateral microinjection of okadaic acid (OA) on spatial memory function assessed in one day water maze paradigm and hippocampal structure in rats. Rats were divided in following groups: Control(icv) - rats injected with ICV and aCSF; Control(hipp) - rats injected intrahippocampally with aCSF; OAicv - rats injected with ICV and OA; OAhipp - rats injected intrahippocampally with OA. Nissl staining of hippocampal sections showed that the pyramidal cell loss in OAhipp group is significantly higher than that in the OAicv. The results of behavioral experiments showed that ICV or intrahippocampal bilateral microinjection of OA did not affect learning process and short-term spatial memory but induced impairment in spatial long-term memory assessed in probe test performance 24 h after training. OA-induced spatial memory impairment may be attributed to the hippocampal cell death. Based on these results OA induced memory deficit and hippocampal cell loss in rat may be considered as a potential animal model for preclinical evaluation of antidementic drug activity.

Osteoarticular Expression of Musashi-1 in an Experimental Model of Arthritis

Science.gov (United States)

O'Valle, Francisco; Peregrina, Magdalena; Crespo-Lora, Vicente; Galindo-Moreno, Pablo; Roman, Maria; Aneiros-Fernandez, Jose; Aguilar, David; Gonzalez-Rey, Elena; Delgado, Mario; Hernandez-Cortes, Pedro

2015-01-01

Background. Collagen-induced arthritis (CIA), a murine experimental disease model induced by immunization with type II collagen (CII), is used to evaluate novel therapeutic strategies for rheumatoid arthritis. Adult stem cell marker Musashi-1 (Msi1) plays an important role in regulating the maintenance and differentiation of stem/precursor cells. The objectives of this investigation were to perform a morphological study of the experimental CIA model, evaluate the effect of TNFα-blocker (etanercept) treatment, and determine the immunohistochemical expression of Msi1 protein. Methods. CIA was induced in 50 male DBA1/J mice for analyses of tissue and serum cytokine; clinical and morphological lesions in limbs; and immunohistochemical expression of Msi1. Results. Clinically, TNFα-blocker treatment attenuated CIA on day 32 after immunization (P < 0.001). Msi1 protein expression was significantly higher in joints damaged by CIA than in those with no lesions (P < 0.0001) and was related to the severity of the lesions (Spearman's rho = 0.775, P = 0.0001). Conclusions. Treatment with etanercept attenuates osteoarticular lesions in the murine CIA model. Osteoarticular expression of Msi1 protein is increased in joints with CIA-induced lesion and absent in nonlesioned joints, suggesting that this protein is expressed when the lesion is produced in order to favor tissue repair. PMID:26064941

Experimental study of neuropharmacological profile of Euphorbia pulcherrima in mice and rats

Directory of Open Access Journals (Sweden)

Kundan Kr Singh

2012-01-01

Full Text Available Context: Euphorbia pulcherrima (EP belongs to the family: Euphorbiaceae and Genus: Euphorbia. Many species of Euphorbia have been reported as having beneficial properties like anticonvulsive effect, central analgesic properties, antipyretic action, central depressant action and strong sedative effect. However, little study has been done and published on EP. Aims: To observe and evaluate various neuropharmacological effects like antinociceptive effect, anticonvulsant effect, motor in-coordination, pentobarbital induced sleeping time and behavioral responses of EP in mice and rats. Setting and Design: Quantitative experimental study in mice and rats by various experimental models. Materials and Methods: Different experimental models were used to assess the antinociceptive effect (hotplate, tail flick and acetic acid induced writhing test, anticonvulsant effect (Maximal Electroshock Seizure test [MES] and Pentylenetetrazole induced seizures [PTZ], motor in-coordination effect (Rota rod test, pentobarbital induced sleeping time and behavioral responses of EP in mice and rats after oral administration of EP crude dried extracts in three different doses (250, 500 and 1000 mg/kg. Statistical Analysis Used: The significance of difference with respect to control was evaluated using the Mann-Whitney U test. A probability (P-value level less than 0.05 was considered as significant. Results: In MES test model, duration of tonic hind limb extension in mice treated with EP was significantly less as compared to vehicle treated group. EP was most effective in a dose of 1000 mg/kg. There was also significant increase in the latency and decrease in the incidence of convulsions with the use of EP in three different doses in PTZ induced seizure model. Conclusions: This study showed EP (crude dried extracts to possess anticonvulsant properties but no effect on motor co-ordination and anxiety.

PEMFC modeling and experimental validation

Energy Technology Data Exchange (ETDEWEB)

Vargas, J.V.C. [Federal University of Parana (UFPR), Curitiba, PR (Brazil). Dept. of Mechanical Engineering], E-mail: jvargas@demec.ufpr.br; Ordonez, J.C.; Martins, L.S. [Florida State University, Tallahassee, FL (United States). Center for Advanced Power Systems], Emails: ordonez@caps.fsu.edu, martins@caps.fsu.edu

2009-07-01

In this paper, a simplified and comprehensive PEMFC mathematical model introduced in previous studies is experimentally validated. Numerical results are obtained for an existing set of commercial unit PEM fuel cells. The model accounts for pressure drops in the gas channels, and for temperature gradients with respect to space in the flow direction, that are investigated by direct infrared imaging, showing that even at low current operation such gradients are present in fuel cell operation, and therefore should be considered by a PEMFC model, since large coolant flow rates are limited due to induced high pressure drops in the cooling channels. The computed polarization and power curves are directly compared to the experimentally measured ones with good qualitative and quantitative agreement. The combination of accuracy and low computational time allow for the future utilization of the model as a reliable tool for PEMFC simulation, control, design and optimization purposes. (author)

Variations of helicon wave induced radial plasma transport in different experimental conditions

International Nuclear Information System (INIS)

Petrzilka, V.

1993-08-01

Variations of the helicon wave induced radial plasma transport are presented in dependence on values of the plasma radius, magnetostatic field, plasma density, frequency of the helicon wave and on the ion charge. 22 refs., 14 figs

Experimental alveolitis in rats: microbiological, acute phase response and histometric characterization of delayed alveolar healing.

Science.gov (United States)

Rodrigues, Moacyr Tadeu Vicente; Cardoso, Camila Lopes; Carvalho, Paulo Sérgio Perri de; Cestari, Tânia Mary; Feres, Magda; Garlet, Gustavo Pompermaier; Ferreira, Osny

2011-01-01

The pathogenesis of alveolitis is not well known and therefore experimental situations that mimic some features of this disease should be developed. In this study, the evolution of the experimentally induced infection in rat sockets is characterized, which leads to clinical signs of suppurative alveolitis with remarkable wound healing disturbs. Non-infected (Group I) and experimentally infected sockets in Rattus novergicus (Group II) were histometrically evaluated regarding the kinetics of alveolar healing. In addition, the characterization of the present bacteria in inoculation material and the serum levels of C-reactive protein (CRP) were performed. The detected species were Capnocytophaga ochracea, Fusobacterium nucleatum ss nucleatum, Prevotella melaninogenica, Streptococcus anginosus, Treponema socranskii and Streptococcus sanguis. All experimentally infected rats developed suppurative alveolitis, showing higher levels of CRP in comparison to those non-infected ones. Furthermore, infected rats presented a significant delayed wound healing as measured by the histometric analysis (higher persistent polymorphonuclear infiltrate and lower density of newly formed bone). These findings indicate that rat sockets with experimentally induced infection produced higher levels of serum CRP, showing the potential of disseminated infection and a disturb in the alveolar repair process in an interesting experimental model for alveolitis studies.

Secondary current properties generated by wind-induced water waves in experimental conditions

Directory of Open Access Journals (Sweden)

Michio Sanjou

2014-06-01

Full Text Available Secondary currents such as the Langmuir circulation are of high interest in natural rivers and the ocean because they have striking impacts on scour, sedimentation, and mass transport. Basic characteristics have been well-studied in straight open-channel flows. However, little is known regarding secondary circulation induced by wind waves. The presented study describes the generation properties of wind waves observed in the laboratory tank. Wind-induced water waves are known to produce large scale circulations. The phenomenon is observed together with high-speed and low-speed streaks, convergence and divergence zones, respectively. Therefore, it is important to determine the hydrodynamic properties of secondary currents for wind-induced water waves within rivers and lakes. In this study, using two high-speed CMOS cameras, stereoscopic particle image velocimetry (PIV measurements were conducted in order to reveal the distribution of all three components of velocity vectors. The experiments allowed us to investigate the three-dimensional turbulent structure under water waves and the generation mechanism of large-scale circulations. Additionally, a third CMOS camera was used to measure the spanwise profile of thefree-surface elevation. The time-series of velocity components and the free-surface were obtained simultaneously. From our experiments, free-surface variations were found to influence the instantaneous velocity distributions of the cross-sectional plane. We also considered thegeneration process by the phase analysis related to gravity waves and compared the contribution of the apparent stress.

Recrystallization induced plasticity in austenite and ferrite

International Nuclear Information System (INIS)

Huang Mingxin; Pineau, André; Bouaziz, Olivier; Vu, Trong-Dai

2012-01-01

Highlights: ► Plasticity can be induced by recrystallization in austenite and ferrite. ► Strain rate is proportional to recrystallization kinetics. ► Overall atomic flux selects a preferential direction may be the origin. - Abstract: New experimental evidences are provided to demonstrate that plastic strain can be induced by recrystallization in austenite and ferrite under an applied stress much smaller than their yield stresses. Such Recrystallization Induced Plasticity (RIP) phenomenon occurs because the overall atomic flux during recrystallization follows a preferential direction imposed by the applied stress.

Characterization of textural and hydric heterogeneities in argillaceous geo-materials using induced polarization method: application to the excavation damaged zone (EDZ) of the Tournemire experimental station

International Nuclear Information System (INIS)

Okay, Gonca

2011-01-01

This Ph-D thesis investigates the potential of clay rocks for deep geological disposal of radioactive waste. Underground excavations are responsible in their vicinity a region, where the clay-rock is damaged or disturbed. This region must to be characterized to ensure the safety of repositories. The extension of the excavation damaged zone (EDZ) and its evolution over time have been investigated thought electrical resistivity and induced polarization methods from three galleries belonging to the French Institute of Radioprotection and Nuclear Safety (IRSN)'s experimental underground research laboratory of Tournemire (Aveyron, France). Time domain induced polarisation indicates the presence of mineralization (e.g., especially pyrite) located in the structural discontinuities such as tectonic fractures (mm-cm), tectonic fault (m) and calcareous nodules (cm). Combined electrical resistivity and Induced Polarization methods show the possibility to delineate textural changes associated to desaturation of the clay-rock induced by the ventilation of galleries. The impact of the desaturation is particularly observed on the gallery's walls. In addition, Spectral Induced Polarization (SIP) tomography results can be used to discriminate the responses of the de-saturated zones from the fractured zones. We have performed laboratory experiments (in the range 1.4 mHz - 12 kHz) using saturated unconsolidated sand-clay mixtures. The results illustrate that the amplitude of polarization is strongly affected by the surface properties of these mixtures (e.g., cation exchange capacity, specific surface area) and by the volumetric clay content. However, the amplitude of polarization is independent of the concentration of electrolyte. The SIP response is also strongly sensitive to the mineralogy of the clays. (author)

Shock induced response of structural systems analytical and experimental investigations

International Nuclear Information System (INIS)

Stangenberg, F.

1984-01-01

This contribution refers to the behaviour of reinforced concrete structures impacted by deformable missiles. The difference with hard missile impact problems, about which generally more knowledge exists, are point out. Structural response effects beyond the immediate contact face vicinity, beyond the local load introduction zone - i.e. effects of punching shear, of bending, of vibration transmission etc. - are emphasized. Two- and three-dimensional analytical approaches verified by experimental evaluations are discussed, and typical phenomena of the behaviour of reinforced concrete structures subjected to impact loads are demonstrated. (Author) [pt

Splanchnic-aortic inflammatory axis in experimental portal hypertension

Science.gov (United States)

Aller, Maria-Angeles; de las Heras, Natalia; Nava, Maria-Paz; Regadera, Javier; Arias, Jaime; Lahera, Vicente

2013-01-01

Splanchnic and systemic low-grade inflammation has been proposed to be a consequence of long-term prehepatic portal hypertension. This experimental model causes minimal alternations in the liver, thus making a more selective study possible for the pathological changes characteristic of prehepatic portal hypertension. Low-grade splanchnic inflammation after long-term triple partial portal vein ligation could be associated with liver steatosis and portal hypertensive intestinal vasculopathy. In fact, we have previously shown that prehepatic portal hypertension in the rat induces liver steatosis and changes in lipid and carbohydrate metabolism similar to those produced in chronic inflammatory conditions described in metabolic syndrome in humans. Dysbiosis and bacterial translocation in this experimental model suggest the existence of a portal hypertensive intestinal microbiome implicated in both the splanchnic and systemic alterations related to prehepatic portal hypertension. Among the systemic impairments, aortopathy characterized by oxidative stress, increased levels of proinflammatory cytokines and profibrogenic mediators stand out. In this experimental model of long-term triple portal vein ligated-rats, the abdominal aortic proinflammatory response could be attributed to oxidative stress. Thus, the increased aortic reduced-nicotinamide-adenine dinucleotide phosphate [NAD(P)H] oxidase activity could be associated with reactive oxygen species production and promote aortic inflammation. Also, oxidative stress mediated by NAD(P)H oxidase has been associated with risk factors for inflammation and atherosclerosis. The splanchnic and systemic pathology that is produced in the long term after triple partial portal vein ligation in the rat reinforces the validity of this experimental model to study the chronic low-grade inflammatory response induced by prehepatic portal hypertension. PMID:24307792

Metformin ameliorates insulitis in STZ-induced diabetic mice

Directory of Open Access Journals (Sweden)

Guo-Jun Jiang

2017-04-01

Full Text Available Background & Aims Metformin is currently the most widely used first-line hypoglycemic agent for diabetes mellitus. Besides glucose-lowering action, there is increasingly interest in the potential anti-inflammatory action of this drug. In the present study, we investigated the actions of metformin on experimental insulitis using STZ-induced diabetic mice. Methods Mice with acute diabetes induced by STZ were administered metformin by gavage. Changes of blood glucose and body weight, and the daily amount of food and water intake were measured. Pancreatic tissues were collected for histologic analyses. Pathological assessment and immunohistochemistry analysis were used to determine the effect of metformin on insulitis. Inflammatory cytokines in the pancreas and insulin levels were measured through ELISA analysis. Results Metformin significantly reduced blood glucose levels and improved aberrant water intake behavior in experimental diabetic mice. No significant differences were observed in terms of body weight and food intake behavior in metformin-treated animals. In the STZ-induced model of diabetes, we found the appearance of pronounced insulitis. However, metformin administration reduced the severity of insulitis assessed by blind pathological scoring. In addition, metformin treatment improved insulin levels in experimental diabetic mice. ELISA assay revealed decreased levels of inflammatory response marker IL-1β and TNF-α in the pancreatic tissues following metformin treatment. Conclusion Metformin attenuated insulitis in the STZ-induced mice model of diabetes. This islet-protective effect might be partly correlated with the anti-inflammatory action of metformin.

Experimental study of the Richtmyer-Meshkov instability induced by a Mach 3 shock wave

International Nuclear Information System (INIS)

BP Puranik; JG Oakley; MH Anderson; R Bonaazza

2003-01-01

OAK-B135 An experimental investigation of a shock-induced interfacial instability (Richtmyer-Meshkov instability) is undertaken in an effort to study temporal evolution of interfacial perturbations in the late stages of development. The experiments are performed in a vertical shock tube with a square cross-section. A membraneless interface is prepared by retracting a sinusoidally shaped metal plate initially separating carbon dioxide from air, with both gases initially at atmospheric pressure. With carbon dioxide above the plate, the Rayleigh-Taylor instability commences as the plate is retracted and the amplitude of the initial sinusoidal perturbation imposed on the interface begins to grow. The interface is accelerated by a strong shock wave (M=3.08) while its shape is still sinusoidal and before the Kelvin-Helmhotz instability distorts it into the well known mushroom-like structures; its initial amplitude to wavelength ratio is large enough that the interface evolution enters its nonlinear stage very shortly after shock acceleration. The pre-shock evolution of the interface due to the Rayleigh-Taylor instability and the post-shock evolution of the interface due to the Richtmyer-Meshkov instability are visualized using planar Mie scattering. The pre-shock evolution of the interface is carried out in an independent set of experiments. The initial conditions for the Richtmyer-Meshkov experiment are determined from the pre-shock Rayleigh-Taylor growth. One image of the post-shock interface is obtained per experiment and image sequences, showing the post-shock evolution of the interface, are constructed from several experiments. The growth rate of the perturbation amplitude is measured and compared with two recent analytical models of the Richtmyer-Meshkov instability

Micro-scale experimental study of Microbial-Induced Carbonate Precipitation (MICP) by using microfluidic devices

Science.gov (United States)

Wang, Y.; Soga, K.; DeJong, J. T.; Kabla, A.

2017-12-01

Microbial-induced carbonate precipitation (MICP), one of the bio-mineralization processes, is an innovative subsurface improvement technique for enhancing the strength and stiffness of soils, and controlling their hydraulic conductivity. These macro-scale engineering properties of MICP treated soils controlled by micro-scale factors of the precipitated carbonate, such as its content, amount and distribution in the soil matrix. The precipitation process itself is affected by bacteria amount, reaction kinetics, porous medium geometry and flow distribution in the soils. Accordingly, to better understand the MICP process at the pore scale a new experimental technique that can observe the entire process of MICP at the pore-scale was developed. In this study, a 2-D transparent microfluidic chip made of Polydimethylsiloxane (PDMS) representing the soil matrix was designed and fabricated. A staged-injection MICP treatment procedure was simulated inside the microfluidic chip while continuously monitored using microscopic techniques. The staged-injection MICP treatment procedure started with the injection of bacteria suspension, followed with the bacteria setting for attachment, and then ended with the multiple injections of cementation liquid. The main MICP processes visualized during this procedure included the bacteria transport and attachment during the bacteria injection, the bacteria attachment and growth during the bacteria settling, the bacteria detachment during the cementation liquid injection, the cementation development during the cementation liquid injection, and the cementation development after the completion of cementation liquid injection. It is suggested that the visualization of the main MICP processes using the microfluidic technique can improve understating of the fundamental mechanisms of MICP and consequently help improve the treatment technique for in situ implementation of MICP.

Comparative Study of Experimentally Induced Cancer of the Kidney in Mice and Rats with X-Rays

Energy Technology Data Exchange (ETDEWEB)

Maldague, P. [Cancer Institute, University of Louvain (Belgium)

1969-11-15

Local irradiation of a kidney in rats and mice results in the development of radiation- induced cancers in the irradiated kidney. The production of these cancers is considerably greater in rats than in mice, and their frequency depends on: (1) The X-ray dose absorbed by the kidney; (2) The latency period which is longer for carcinomas than for sarcomas; and (3) The degree and extent of renal radiation- induced lesions. A study of the relationship between dose and carcinogenic effect has enabled us to define three types of X-ray dose: (a) An ineffective dose of 570 rads at which the inducement of cancer is zero; (b) An optimum dose of 1700 rads at which the frequency of renal tumours is maximal (85%); and (c) Excessive doses between 7000 and 14 000 rads after which the frequency of radiation-induced cancers of the kidney approaches zero. Studies of the latent period have shown that radiation-induced cancers of the kidney in mice do not appear until 790 days after irradiation, whereas in rats the first cancers appear after 280 days. As regards the mechanism of the inducement of renal cancer by radiation, we have been able to establish that cancers of the kidney only develop from visible renal lesions. Radiation-induced cancers have not been observed in rats or mice whose kidneys were morphologically and functionally normal. (author)

Experimental techniques

International Nuclear Information System (INIS)

Roussel-Chomaz, P.

2007-01-01

This lecture presents the experimental techniques, developed in the last 10 or 15 years, in order to perform a new class of experiments with exotic nuclei, where the reactions induced by these nuclei allow to get information on their structure. A brief review of the secondary beams production methods will be given, with some examples of facilities in operation or under project. The important developments performed recently on cryogenic targets will be presented. The different detection systems will be reviewed, both the beam detectors before the targets, and the many kind of detectors necessary to detect all outgoing particles after the reaction: magnetic spectrometer for the heavy fragment, detection systems for the target recoil nucleus, γ detectors. Finally, several typical examples of experiments will be detailed, in order to illustrate the use of each detector either alone, or in coincidence with others. (author)

[Trigeminal purinergic P2X4 receptor involved in experimental occlusal interference-induced hyperalgesia in rat masseter muscle].

Science.gov (United States)

Xu, Xiaoxiang; Cao, Ye; Ding, Tingting; Fu, Kaiyuan; Xie, Qiufei

2016-03-01

To explore the expression of purinergic p2X4 receptor (P2X4R) in trigeminal ganglion of rats after occlusal interference. Investigation of peripheral receptor mechanism of occlusal interference-induced masticatory muscle pain will aid the development of drug intervention against this condition. Experimental occlusal interference was established by application of 0.4 mm metal crown to the upper right first molar of male Sprague-Dawley rats. Real-time PCR assay was used to investigate P2X4R mRNA level in trigeminal ganglion in rats with occlusal interference for 3, 7, 10 and 14 days and in control rats without occlusal interference (n=5 in each). Retrograde labelling combining immunofluorescence was performed to evaluate the percentage of P2X4R-positive cells in masseter afferent neurons (n=5 in each group). Graded concentrations of P2XR antagonist TNP-ATP (0.1, 10, 125, 250, 500 μmol/L) or saline (n=5 in each group) was administrated in right masseter and the mechanical sensitivity of bilateral masseters was measured before occlusal interference application, before the injection, and 30 min as well as 60 min after the injection. Compared with control rats (P2X4R mRNA: right side: 1.00±0.26, left side: 0.94± 0.21; percentage of P2X4R-positive masseter afferents: right side: [64.3±6.3]%, left side: [67.7±5.8]%), the level of P2X4R mRNA in bilateral trigeminal ganglia (right side: 5.98±3.56; left side: 5.06±2.88) of rats with occlusal interference for 7 days up-regulated (Pocclusal interference-induced masseter hyperalgesia.

Blockade of Extracellular ATP Effect by Oxidized ATP Effectively Mitigated Induced Mouse Experimental Autoimmune Uveitis (EAU.

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Ronglan Zhao

Full Text Available Various pathological conditions are accompanied by ATP release from the intracellular to the extracellular compartment. Extracellular ATP (eATP functions as a signaling molecule by activating purinergic P2 purine receptors. The key P2 receptor involved in inflammation was identified as P2X7R. Recent studies have shown that P2X7R signaling is required to trigger the Th1/Th17 immune response, and oxidized ATP (oxATP effectively blocks P2X7R activation. In this study we investigated the effect of oxATP on mouse experimental autoimmune uveitis (EAU. Our results demonstrated that induced EAU in B6 mice was almost completely abolished by the administration of small doses of oxATP, and the Th17 response, but not the Th1 response, was significantly weakened in the treated mice. Mechanistic studies showed that the therapeutic effects involve the functional change of a number of immune cells, including dendritic cells (DCs, T cells, and regulatory T cells. OxATP not only directly inhibits the T cell response; it also suppresses T cell activation by altering the function of DCs and Foxp3+ T cell. Our results demonstrated that inhibition of P2X7R activation effectively exempts excessive autoimmune inflammation, which may indicate a possible therapeutic use in the treatment of autoimmune diseases.

Cardenolide-Induced Lysosomal Membrane Permeabilization Demonstrates Therapeutic Benefits in Experimental Human Non-Small Cell Lung Cancers

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Tatjana Mijatovic

2006-05-01

Full Text Available Non-small cell lung cancers (NSCLCs are the leading cause of cancer deaths in most developed countries. Targeting heat shock protein 70 (Hsp70 expression and function, together with the induction of lysosomal membrane permeabilization (LMP, could overcome the multiple anti-cell death mechanisms evidenced in NSCLCs that are responsible for the failure of currently used chemotherapeutic drugs. Because cardenolides bind to the sodium pump, they affect multiple signaling pathways and thus have a number of marked effects on tumor cell behavior. The aim of the present study was to characterize in vitro and in vivo the antitumor effects of a new cardenolide (UNBS1450 on experimental human NSCLCs. UNBS1450 is a potent source of in vivo antitumor activity in the case of paclitaxeland oxaliplatin-resistant subcutaneous human NCIH727 and orthotopic A549 xenografts in nude mice. In vitro UNBS1450-mediated antitumor activity results from the induction of nonapoptotic cell death. UNBS1450 mediates the decrease of Hsp70 at both mRNA and protein levels, and this is at least partly due to UNBS1450-induced downregulation of NFAT5/ TonEBP (a factor responsible for the transcriptional control of Hsp70. These effects were paralleled by the induction of LMP, as evidenced by acridine orange staining and immunofluorescence analysis for cathepsin B accumulation.

Adaptations in the gait pattern with experimental hamstring pain

DEFF Research Database (Denmark)

Henriksen, M; Mortensen, Sara Rosager; Aaboe, J

2011-01-01

and little attention has been given to how pain in other muscles affects functional movement. The purpose of this study was to investigate the changes in the gait patterns of healthy subjects that occur during experimental muscle pain in the biceps femoris. In a cross-over study design, 14 healthy volunteers...... underwent EMG assisted 3D gait analyses before, during and after experimental biceps femoris pain induced by intramuscular injections of hypertonic saline. Isotonic saline injections were administered as a non-painful control. The experimental biceps femoris pain led to reductions in hip extensor moments......, knee flexor and lateral rotator moments. No changes in lower extremity kinematics and EMG activity in any of the recorded muscles were observed. It is concluded that experimental muscle pain in the biceps femoris leads to changes in the gait pattern in agreement with unloading of the painful muscle...

A new magnetorheological damper with improved displacement differential self-induced ability

International Nuclear Information System (INIS)

Hu, Guoliang; Zhou, Wei; Li, Weihua

2015-01-01

This work is an extension of our previous study on the development of a linear variable differential sensor (LVDS)-based magnetorheological (MR) damper with self-sensing capability, where a new MR damper integrated with LVDS technology was developed and prototyped, then its self-induced performance under static and dynamic working conditions was experimentally evaluated. The results of the static and dynamic experiments indicated that the self-induced voltage was proportional to the displacement of the damper. Moreover, the damping performance of this new MR damper was also evaluated through an experimental study. Compared with our previous study, the new MR damper performed better in terms of its self-induced sensing ability and damping capacity. (technical note)

Experimental investigation of fundamental processes in mining induced fracturing and rock instability.

CSIR Research Space (South Africa)

Napier, JAL

2002-03-01

Full Text Available The main themes of the project GAP601b have been experimental investigations of creep effects, further underground observations of time-dependent behaviour, investigation of scale effects and rock mass stability and studies of the interaction...

Inhibitory effect of cucurbitacin B on imiquimod-induced skin inflammation

Energy Technology Data Exchange (ETDEWEB)

Li, Zheng Jun; Shin, Jung-Min; Choi, Dae-Kyoung; Lim, Seul Ki [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon (Korea, Republic of); Yoon, Tae-Jin [Department of Dermatology, School of Medicine, Gyeongsang National University, Jinju (Korea, Republic of); Lee, Young Ho [Department of Anatomy, School of Medicine, Chungnam National University, Daejeon (Korea, Republic of); Sohn, Kyung-Cheol; Im, Myung; Lee, Young; Seo, Young-Joon; Kim, Chang Deok [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon (Korea, Republic of); Lee, Jeung-Hoon, E-mail: jhoon@cnu.ac.kr [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon (Korea, Republic of); Skin Med Company, Daejeon (Korea, Republic of)

2015-04-17

Psoriasis is a common skin disease, of which pathogenesis involves the increase of inflammatory reaction in epidermal cells. In an attempt to find therapeutics for psoriasis, we found that cucurbitacin B has an inhibitory potential on imiquimod-induced inflammation of keratinocytes. Cucurbitacin B significantly inhibited imiquimod-induced expression of crucial psoriatic cytokines, such as IL-8 and CCL20, via down-regulation of NF-κB and STAT3 signaling pathway in human keratinocytes. In addition, keratinocyte proliferation was markedly inhibited by cucurbitacin B. The potential beneficial effect of cucurbitacin B on psoriasis was further validated in imiquimod-induced psoriasiform dermatitis of experimental animal. Topical application of cucurbitacin B resulted in significant reduction of epidermal hyperplasia and inflammatory cytokines production, and ameliorated the psoriatic symptom. Taken together, these results suggest that cucurbitacin B may be a potential candidate for the treatment of psoriasis. - Highlights: • Cucurbitacin B has a potential for inhibiting the growth of keratinocytes. • Cucurbitacin B inhibits imiquimod-induced inflammatory reaction in keratinocytes. • Cucurbitacin B inhibits imiquimod-induced psoriasiform dermatitis in experimental animal.

Inhibitory effect of cucurbitacin B on imiquimod-induced skin inflammation

International Nuclear Information System (INIS)

Li, Zheng Jun; Shin, Jung-Min; Choi, Dae-Kyoung; Lim, Seul Ki; Yoon, Tae-Jin; Lee, Young Ho; Sohn, Kyung-Cheol; Im, Myung; Lee, Young; Seo, Young-Joon; Kim, Chang Deok; Lee, Jeung-Hoon

2015-01-01

Psoriasis is a common skin disease, of which pathogenesis involves the increase of inflammatory reaction in epidermal cells. In an attempt to find therapeutics for psoriasis, we found that cucurbitacin B has an inhibitory potential on imiquimod-induced inflammation of keratinocytes. Cucurbitacin B significantly inhibited imiquimod-induced expression of crucial psoriatic cytokines, such as IL-8 and CCL20, via down-regulation of NF-κB and STAT3 signaling pathway in human keratinocytes. In addition, keratinocyte proliferation was markedly inhibited by cucurbitacin B. The potential beneficial effect of cucurbitacin B on psoriasis was further validated in imiquimod-induced psoriasiform dermatitis of experimental animal. Topical application of cucurbitacin B resulted in significant reduction of epidermal hyperplasia and inflammatory cytokines production, and ameliorated the psoriatic symptom. Taken together, these results suggest that cucurbitacin B may be a potential candidate for the treatment of psoriasis. - Highlights: • Cucurbitacin B has a potential for inhibiting the growth of keratinocytes. • Cucurbitacin B inhibits imiquimod-induced inflammatory reaction in keratinocytes. • Cucurbitacin B inhibits imiquimod-induced psoriasiform dermatitis in experimental animal

Tratamento farmacológico da hiperalgesia experimentalmente induzida pelo núcleo pulposo Pharmacologic treatment of hyperalgesia experimentally induced by nucleus pulposus

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André Luiz de Souza Grava

2010-01-01

Full Text Available OBJETIVO: Avaliar o efeito de drogas anti-inflamatórias (dexametasona, indometacina, atenolol, indometacina e atenolol e analgésica (morfina sobre a hiperalgesia experimentalmente induzida pelo núcleo pulposo em contato com o gânglio da raiz dorsal de L5. MÉTODOS: Trinta ratos Wistar machos com peso de 220 a 250g foram utilizados no estudo. A indução da hiperalgesia foi realizada por meio do contato de fragmento de núcleo pulposo retirado da região sacrococcígea e colocado sobre o gânglio da raiz dorsal de L5. Os 30 animais foram divididos em grupos experimentais de acordo com a droga utilizada. As drogas foram administradas durante duas semanas a partir da realização do procedimento cirúrgico para a indução da hiperalgesia. A hiperalgesia mecânica e térmica foram avaliadas por meio do teste da pressão constante da pata, von Frey eletrônico e Hargraves por um período de sete semanas. RESULTADOS: A maior redução da hiperalgesia foi observada no grupo de animais tratados pela morfina, seguido pela dexametasona, indometacina e atenolol. A redução da hiperalgesia foi observada após a interrupção da administração das drogas, com exceção do grupo de animais tratados com morfina, nos quais ocorreu aumento da hiperalgesia após a interrupção do tratamento. CONCLUSÕES: A hiperalgesia induzida pelo contato do núcleo pulposo com o gânglio da raiz dorsal pode ser reduzida com a administração de anti-inflamatórios e analgésicos, tendo sido observado a maior redução da hiperalgesia com a administração da morfina e dexametasona.OBJECTIVE: To evaluate the effect of antiinflammatory (dexamethasone, indomethacin, atenolol, indomethacin and atenolol and analgesic drugs (morphine on hyperalgesia experimentally induced by nucleus pulposus (NP contact with the L5- dorsal root ganglion (DRG. METHODS: Thirty male Wistar rats with weights ranging from 220 to 250 g were used in the study. The hyperalgesia was induced by

Reducing atelectasis attenuates bacterial growth and translocation in experimental pneumonia

NARCIS (Netherlands)

van Kaam, Anton H.; Lachmann, Robert A.; Herting, Egbert; de Jaegere, Anne; van Iwaarden, Freek; Noorduyn, L. Arnold; Kok, Joke H.; Haitsma, Jack J.; Lachmann, Burkhard

2004-01-01

Besides being one of the mechanisms responsible for ventilator-induced lung injury, atelectasis also seems to aggravate the course of experimental pneumonia. In this study, we examined the effect of reducing the degree of atelectasis by natural modified surfactant and/or open lung ventilation on

Tumor vascularity of experimentally induced VX2 carcinoma in the rabbit thigh: evaluation with enhanced power doppler sonography and DSA correlated with histopathologic findings

Energy Technology Data Exchange (ETDEWEB)

Kim, Young Hoon; Han, Joon Koo; Chung, Jin Wook; Lee, Kyoung Ho; Kim, Se Hyung; Kim, Seog Joon; Choi, Byung Ihn; Chang, Kee Hyun [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

2002-05-01

To describe findings of enhanced power Doppler sonography and DSA in experimentally induced VX2 carcinomas in rabbit thigh and to correlate the imaging findings with the histopathologic features. A total of 30 VX2 carcinomas were implanted in rabbit thigh, and after conventional and enhanced power Doppler sonography and DSA, histopathologic examination was performed. Enhanced power Doppler sonography and DSA, were used to determine the distribution pattern of tumor vascularity; to assess its grade and the percentage of a tumor area occupied by vessels, conventional and enhanced power Doppler sonography, as well as DSA, were used. The grade of necrosis and the development of fibrovascular stroma and capsule were histopathologically determined. The findings of power Doppler sonography were compared with those of DSA and the imaging features were correlated with the histopathologic features. At enhanced power Doppler sonography, the signal was either avascular (n=9), peripheral (n=15) or diffuse (n=6), while at DSA, the corresponding totals were eight, fourteen and eight. There was statistically significant corelation between enhanced power Doppler sonogrpahy and DSA, both in their depiction of the distribution of patterns of tumor vascularity and as regards their findings of grade and percentage of vascular area. As determined by both conventional and enhanced power Doppler sonogrpahy, and by DSA, grade of necrosis and the development of fibrovascular stroma and a capsule correlated with grade and the percentage of vascular area. Experimentally induced VX2 carcinomas in rabbit thigh demonstrated various patterns of tumor vascularity, and the findings of enhanced power Doppler sonography correlated with those of DSA. Tumor vascularity, as demonstrated by two imaging modalities, correlated closely with grade of necrosis and the development of fibrovascular stroma and a capsule, as revealed by histopathologic examination.

Tumor vascularity of experimentally induced VX2 carcinoma in the rabbit thigh: evaluation with enhanced power doppler sonography and DSA correlated with histopathologic findings

International Nuclear Information System (INIS)

Kim, Young Hoon; Han, Joon Koo; Chung, Jin Wook; Lee, Kyoung Ho; Kim, Se Hyung; Kim, Seog Joon; Choi, Byung Ihn; Chang, Kee Hyun

2002-01-01

To describe findings of enhanced power Doppler sonography and DSA in experimentally induced VX2 carcinomas in rabbit thigh and to correlate the imaging findings with the histopathologic features. A total of 30 VX2 carcinomas were implanted in rabbit thigh, and after conventional and enhanced power Doppler sonography and DSA, histopathologic examination was performed. Enhanced power Doppler sonography and DSA, were used to determine the distribution pattern of tumor vascularity; to assess its grade and the percentage of a tumor area occupied by vessels, conventional and enhanced power Doppler sonography, as well as DSA, were used. The grade of necrosis and the development of fibrovascular stroma and capsule were histopathologically determined. The findings of power Doppler sonography were compared with those of DSA and the imaging features were correlated with the histopathologic features. At enhanced power Doppler sonography, the signal was either avascular (n=9), peripheral (n=15) or diffuse (n=6), while at DSA, the corresponding totals were eight, fourteen and eight. There was statistically significant corelation between enhanced power Doppler sonogrpahy and DSA, both in their depiction of the distribution of patterns of tumor vascularity and as regards their findings of grade and percentage of vascular area. As determined by both conventional and enhanced power Doppler sonogrpahy, and by DSA, grade of necrosis and the development of fibrovascular stroma and a capsule correlated with grade and the percentage of vascular area. Experimentally induced VX2 carcinomas in rabbit thigh demonstrated various patterns of tumor vascularity, and the findings of enhanced power Doppler sonography correlated with those of DSA. Tumor vascularity, as demonstrated by two imaging modalities, correlated closely with grade of necrosis and the development of fibrovascular stroma and a capsule, as revealed by histopathologic examination

Radiation-induced centers in inorganic glasses

International Nuclear Information System (INIS)

Brekhovskikh, S.M.; Tyul'nin, V.A.

1988-01-01

The nature, structure and formation mechanisms of radiation-induced colour centers, EPR, luminescence, generated ionizing radiation in nonorganic oxide glasses are considered. Experimental material covering both fundamental aspects of radiation physics and glass chemistry, and aspects intimately connected with the creation of new materials with the given radiation-spectral characteristics, with possibilities to prepare radiation-stable and radiation-sensitive glasses is systematized and generalized. Considerable attention is paid to the detection of radiation-induced center binding with composition, glass structures redox conditions for their synthesis. Some new possibilities of practical application of glasses with radiation-induced centers, in particular, to record optical information are reflected in the paper

Effect of hyperthermia on experimental acute pancreatitis Efeito da hipertermia na pancreatite aguda experimental

Directory of Open Access Journals (Sweden)

José Luiz Jesus de Almeida

2006-12-01

Full Text Available BACKGROUD: Recent studies indicate that hyperthermia can change inflammatory mechanisms and protect experimental animals from deleterious effects of secretagogue-induced acute pancreatitis AIM: To evaluate the effects of hyperthermia post-treatment on cerulein-induced acute pancreatitis in rats METHODS: Twenty animals were divided in two groups: group I (n = 10, rats with cerulein-induced acute pancreatitis undergone hyperthermia, and group II (n = 10, animals with cerulein-induced acute pancreatitis that were kept normothermic. In all groups, amylase serum levels, histologic damage, vascular permeability and pancreatic water content were assessed. Acute pancreatitis was induced by administration of two cerulein injections (20 mcg/kg. A single dose of Evans' blue dye was administered along with the second dose of cerulein. All animals also received a subcutaneous injection of saline solution. After this process, animals undergone hyperthermia were heated in a cage with two 100 W lamps. Body temperature was increased to 39.5ºC and maintained at that level for 45 minutes. Normothermia rats were kept at room temperature in a second cage RESULTS: Control animals had typical edema, serum amylase activity and morphologic changes of this acute pancreatitis model. Hyperthermia post-treatment ameliorated the pancreatic edema, whereas the histologic damage and the serum amylase level remained unchanged CONCLUSIONS: The findings suggest a beneficial effect of the thermal stress on inflammatory edema in experimental acute pancreatitis.RACIONAL: Estudos recentes indicam que a hipertermia pode modificar mecanismos inflamatórios e proteger animais experimentais dos efeitos deletérios da pancreatite aguda induzida por secretagogos OBJETIVO: Avaliar a eficácia da hipertermia como tratamento da pancreatite aguda induzida por ceruleína em ratos MÉTODOS: Vinte animais foram divididos em dois grupos: grupo I (n = 10, ratos com pancreatite aguda induzida por

Suppressive effects of a novel compound on interphotoreceptor retinoid-binding protein-induced experimental autoimmune uveoretinitis in rats

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Jun-ichi Sakai

1999-01-01

Full Text Available The immunosuppressive effect of ethyl O-(N-(pcarboxyphenyl-carbamoyl-mycophenolate(CAM was examined in interphotoreceptor retinoid-binding protein (IRBP-induced experimental autoimmune uveoretinitis (EAU in rats. Lewis rats immunized with bovine IRBP were treated with various oral doses of CAM postimmunization. The degree of inflammation was assessed clinically each day and histologically on day 14 or day 20. Production of various cytokines and IRBP-specific antibody, as well as IRBP-specific proliferation response, was assessed. Complete inhibition of EAU in rats, both by clinical and histologic criteria, was achieved with 50 mg/kg CAM when administered daily for 14 days following IRBP immunization. Partial inhibition was observed at lesser doses of CAM. This CAM-mediated response was accompanied by diminished production of cytokines interleukin-2, interferon-γ and tumor necrosis factor-α, as well as a reduction in IRBP-specific antibody production. Furthermore, administration of CAM either in the induction phase only (days 0–7 or in the effector phase only (days 9 or 11 to day 20 was also capable of suppressing EAU, as assessed histopathologically on day 20. We conclude that CAM is effective in suppressing EAU in rats and its mechanism of action appears to involve modulation of T cell function.

Fetal alcohol spectrum disorders: experimental treatments and strategies for intervention.

Science.gov (United States)

Idrus, Nirelia M; Thomas, Jennifer D

2011-01-01

Despite the known damaging effects of prenatal alcohol exposure, women continue to drink during pregnancy, creating a need for effective interventions and treatments for fetal alcohol spectrum disorders (FASD). Experimental models can be useful in identifying potential treatments, and this article describes the spectrum of experimental therapeutics that currently are being investigated, including pharmacological, nutritional, and environmental/behavioral interventions. Some treatments target the underlying mechanisms that contribute to alcohol-induced damage, protecting against alcohol's teratogenic effects, whereas other treatments may enhance central nervous system plasticity either during alcohol exposure or long after alcohol exposure has ceased. The insights gained to date from experimental models offer several candidates for attenuating the deficits associated with FASD.

Shock-induced electrical activity in polymeric solids. A mechanically induced bond scission model

International Nuclear Information System (INIS)

Graham, R.A.

1979-01-01

When polymeric solids are subjected to high-pressure shock loading, two anomalous electrical phenomena, shock-induced conduction and shock-induced polarization, are observed. The present paper proposes a model of mechanically induced bond scission within the shock front to account for the effects. An experimental study of shock-induced polarization in poly(pyromellitimide) (Vespel SP-1) is reported for shock compressions from 17 to 23% (pressures from 2.5 to 5.4 GPa). Poly(pyromellitimide) is found to be a strong generator of such polarization and the polarization is found to reflect an irreversible or highly hysteretic process. The present measurements are combined with prior measurements to establish a correlation between monomer structure and strength of shock-induced polarization; feeble signals are observed in the simpler monomer repeat units of poly(tetrafluoroethylene) and polyethylene while the strongest signals are observed in more complex monomers of poly(methyl methacrylate) and poly(pyromellitimide). It is also noted that there is an apparent correlation between shock-induced conduction and shock-induced polarization. Such shock-induced electrical activity is also found to be well correlated with the propensity for mechanical bond scission observed in experiments carried out in conventional mechanochemical studies. The bond scission model can account for characteristics observed for electrical activity in shock-loaded polymers and their correlation to monomer structure. Localization of elastic energy within the monomer repeat unit or along the main chain leads to the different propensities for bond scission and resulting shock-induced electrical activity

Experimental induction of struvite uroliths in miniature schnauzer and beagle dogs.

Science.gov (United States)

Klausner, J S; Osborne, C A; O'Leary, T P; Muscoplat, C M; Griffith, D P

1980-09-01

Urease positive staphylococcal urinary tract infection was experimentally induced in 13 dogs. Eight dogs developed cystic and/or urethral struvite calculi in 2 to 8 weeks. No abnormalities in systemic cell mediated immunity were detected in dogs before or after the establishment of the urinary tract infection. Miniature schnauzers whose ancestors had developed stones seemed to be no more susceptible to experimental urinary tract infection and stone formation than miniature schnauzers or beagles whose ancestors did not develop stones.

Experimental cross-sections for proton-induced nuclear reactions on Mo-nat

Czech Academy of Sciences Publication Activity Database

Červenák, Jaroslav; Lebeda, Ondřej

2016-01-01

Roč. 380, AUG (2016), s. 32-49 ISSN 0168-583X R&D Projects: GA MŠk(CZ) LM2011019 Institutional support: RVO:61389005 Keywords : cross-sections * excitation functions * proton-induced nuclear reactions * natural molybdenum * Mo-99 * Tc-99m * Tc96m+g * Tc-95m * thick target yields * U-120M cyclotron Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.109, year: 2016

Study of the immune response to thyroglobulin through a model of experimental autoimmune thyroiditis

International Nuclear Information System (INIS)

Santos Castro, M. dos.

1981-01-01

The cellular and humoral immune response to thyroglobulin of different species was studied in guinea pigs. The experiments described suggested that the immune system can be activated against self-determinants. Human and pork thyroglobulin were able to induce the experimental thyroiditis as well as some immune responses, such as in vitro proliferative response, delayed hypersensitivity and antibodies. Although guinea pig thyroglobulin was unable to induce specific T-lymphocyte proliferation in vitro, delayed hypersensitivity response and antibodies, it was very efficient in inducing the autoimmune thyroiditis. On the contrary, bovine thyroglobulin did not induce experimental autoimmune thyroiditis despite producing good responses as determined by similar in vitro proliferative response, delayed hypersensitivity and on the humoral level. These results suggest that the assays utilised were not able to evaluate the relevant immune response to genesis of the thyroiditis. The determinant selection mechanisms operating in these immune responses are probably selecting determinants not responsible for self-recognition in vivo. It was suggested that the macrophage could be the cell responsible for the presentation of these determinants to the lymphocyte in an immunogenic form. (Author) [pt

Doxorubicin induced neuro- and cardiotoxicities in experimental rats: Protection against oxidative damage by Theobroma cacao Stem bark

Directory of Open Access Journals (Sweden)

A.M. Kosoko

2017-07-01

Full Text Available 80 rats, randomly selected, were divided into 3 treatment groups: pre-, co- and post-treatment; consisting of 6 sub-groups each (5 rats per sub-group: baseline, normal saline (2 mL, α-lipoic acid (20 mg/kg body weight, 200 mg/kg, 400 mg/kg or 800 mg/kg body weight Theobroma cacao stem bark aqueous extract (TCAE. All rats except for baseline group were intoxicated with 20 mg/kg body weight doxorubicin (DOX intraperitoneally. The animals in pre- or post-treatment group received a single dose of DOX (20 mg/kg body weight intraperitoneally 24 h before or after 7 days’ oral administration with TCAE respectively while those in co-treatment group were co-administered 2.86 mg/kg body weight of DOX with either normal saline, α- lipoic acid or TCAE orally for 7 days. Animals were sacrificed (pre- and post- treatment groups were sacrificed on the ninth day while the co-treatment group sacrificed on the 8th day. Brain and heart tissue samples were harvested for enzyme markers of toxicity, oxidative stress and histopathological examinations. DOX intoxication caused significant decrease in activities of LDH and ACP, and increase in γGT and ALP activities in brain tissues while causing a significant increase in LDH, ACP, γGT activities and decrease in ALP activity in the cardiac tissues. DOX intoxication caused a significant increase in concentrations of H2O2 generated, MDA and PC, XO, MPx and NOX activities with concomitant decrease in CAT, SOD, GPx and GST activities, and in concentrations of GSH, AsA and α-Toc in brain and cardiac tissues. Pre-, co- and post-treatment with TCAE at either 200 mg/kg, 400 mg/kg or 800 mg/kg body weight significantly reversed the oxidative damage to the organs induced by DOX-intoxication. The result affirmed that T. cacao stem bark aqueous extract protected against DOX induced oxidative damage in brain and cardiac tissues of experimental rats.

Tumor control induced by Boron Neutron Capture Therapy (BNCT) as a function of dose in an experimental model of liver metastases at 5 weeks follow-up

International Nuclear Information System (INIS)

Pozzi, E C C; Trivillin, V A; Colombo, L L; Monti Hughes, A; Thorp, S; Cardoso, J E; Garabalino, M A; Molinari, A J; Heber, E M; Curotto, Paula; Miller, M; Itoiz, M E; Aromando, R F; Nigg, D W; Schwint, A E

2012-01-01

BNCT has been proposed for the treatment of multifocal, non-resectable, bilobar colorectal liver metastases that do not respond to chemotherapy. We recently reported that BNCT mediated by boronophenylalanine (BPA) induced significant remission of experimental colorectal tumor nodules in rat liver at 3 weeks follow-up with no contributory liver toxicity (Pozzi et al.,2012). The aim of the present study was to evaluate tumor control and potential liver toxicity of BPA-BNCT at 5 weeks follow-up. Prescribed dose was retrospectively evaluated based on blood boron values, allowing for assessment of response over a range of delivered dose values (author)

Detection of parenchymal abnormalities in experimentally induced acute pyelonephritis in rabbits using contrast-enhanced ultrasonography, CT, and MRI

Energy Technology Data Exchange (ETDEWEB)

Ryu, Jeong Ah; Kim, Bo Hyun; Kim, Seung Kwon; Seo, Jin Won [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Jong Sung [Laboratory Animal Research Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2016-12-15

We evaluated the efficacy of contrast-enhanced ultrasonography (CEUS) in detecting acute pyelonephritis (APN) using the rabbit kidney model and compared it with CT and MRI. This study was approved by the Institutional Review Board. In a total of 20 New Zealand White rabbits, APN was induced experimentally. CEUS, CT, and MRI were performed on the first, third, and seventh postoperative days. After imaging studies, the subjects were sacrificed and the pathological diagnosis of APN was confirmed in each animal by a pathologist. Imaging studies were obtained in eight animals, including eight CEUS, four computed tomography (CT), and four magnetic resonance imaging (MRI) images. CEUS depicted diffuse renal enlargement (7), diffuse heterogeneous parenchymal enhancement (6), and focal areas of decreased parenchymal enhancement (6). These findings were well correlated with the CT and MRI findings in five cases in which these studies were available. CT and MRI showed diffuse renal enlargement, diffuse heterogeneous parenchymal enhancement, focal areas of decreased parenchymal enhancement, focal contour bulging, and the finding of perinephric spread of infection. In a rabbit model, CEUS could depict the parenchymal lesions of APN similar to CT or MRI; however, it was limited in depicting the perinephric extension of inflammation.

Multiscale modelling and experimentation of hydrogen embrittlement in aerospace materials

Science.gov (United States)

Jothi, Sathiskumar

Pulse plated nickel and nickel based superalloys have been used extensively in the Ariane 5 space launcher engines. Large structural Ariane 5 space launcher engine components such as combustion chambers with complex microstructures have usually been manufactured using electrodeposited nickel with advanced pulse plating techniques with smaller parts made of nickel based superalloys joined or welded to the structure to fabricate Ariane 5 space launcher engines. One of the major challenges in manufacturing these space launcher components using newly developed materials is a fundamental understanding of how different materials and microstructures react with hydrogen during welding which can lead to hydrogen induced cracking. The main objective of this research has been to examine and interpret the effects of microstructure on hydrogen diffusion and hydrogen embrittlement in (i) nickel based superalloy 718, (ii) established and (iii) newly developed grades of pulse plated nickel used in the Ariane 5 space launcher engine combustion chamber. Also, the effect of microstructures on hydrogen induced hot and cold cracking and weldability of three different grades of pulse plated nickel were investigated. Multiscale modelling and experimental methods have been used throughout. The effect of microstructure on hydrogen embrittlement was explored using an original multiscale numerical model (exploiting synthetic and real microstructures) and a wide range of material characterization techniques including scanning electron microscopy, 2D and 3D electron back scattering diffraction, in-situ and ex-situ hydrogen charged slow strain rate tests, thermal spectroscopy analysis and the Varestraint weldability test. This research shows that combined multiscale modelling and experimentation is required for a fundamental understanding of microstructural effects in hydrogen embrittlement in these materials. Methods to control the susceptibility to hydrogen induced hot and cold cracking and

Beam-induced temperature changes in HVEM irradiations

International Nuclear Information System (INIS)

Garner, F.A.; Thomas, L.E.; Gelles, D.S.

1975-01-01

The peak value of the temperature distribution induced by energy loss of 1.0 MeV electrons in traversing a typical HVEM irradiation specimen can be very substantial. The origin and various features of this distribution were analyzed for a variety of specimen geometries. The major parametric dependencies are shown to be relatively independent of specimen geometry, however, and allow the definition of a scaling relationship that can be employed to predict temperature rises in materials that cannot be measured directly. The use of this scaling relationship requires that the experimenter minimize perturbations of the heat flow due to proximity of the central hole in the specimen. An experimental method of determining directly the magnitude and distribution of beam-induced temperature profiles was developed which utilizes the order-disorder transformation in Fe 3 Al and Cu 3 Au. Scaling of experimentally determined temperature changes leads to more realistic estimates of the total temperature rise than are currently available in various literature tabulations. The factors which determine the optimum selection of irradiation parameters for a given experiment are also discussed

Inhibitory effect of magnesium sulfate on reaction of lipid hyperoxidation after radiation-induced acute brain injuries

International Nuclear Information System (INIS)

Wang Lili; Zhou Juying; Yu Zhiying; Qin Songbing; Xu Xiaoting; Li Li; Tu Yu

2007-01-01

Objective: To explore the protection of magnesium sulfate (MgSO 4 ) on radiation-induced acute brain injuries. Methods: 60 maturity Sprague-Dawley (SD) rats were randomly divided into 3 groups: blank control group, experimental control group and experimental-therapeutic group. The whole brain of SD rats of experimental control group and experimental-therapeutic group was irradiated to a dose of 20 Gy using 6 MeV electron. MgSO 4 was injected intraperitoneally into the rats of experimental-therapeutic group before and after irradiation for five times. At different time points ranging from the 1 d, 7 d, 14 d, 30 d after irradiation, the brain tissue were taken. The xanthine oxidase and colorimetric examination were used to measure the superoxide dismutase (SOD) and malonyldialdehyde (MDA) respectively in the rat brain respectively. Results: Compared with blank control group, the SOD in brain of experimental control group decreased significantly (P 4 used in early stage can inhibit the lipid peroxidation after radiation-induced acute brain injuries and alleviate the damage induced by free radicals to brain tissue. (authors)

Human-Induced Effects on RSS Ranging Measurements for Cooperative Positioning

DEFF Research Database (Denmark)

Della Rosa, Francescantonio; Pelosi, Mauro; Nurmi, Jari

2012-01-01

of human-induced perturbations for enhancing the final positioning accuracy through cooperative schemes has been assessed. It has been proved that the effect of cooperation is very limited if human factors are not taken into account when performing experimental activities.......We present experimental evaluations of human-induced perturbations on received-signal-strength-(RSS-) based ranging measurements for cooperative mobile positioning. To the best of our knowledge, this work is the first attempt to gain insight and understand the impact of both body loss and hand grip...... on the RSS for enhancing proximity measurements among neighbouring devices in cooperative scenarios. Our main contribution is represented by experimental investigations. Analysis of the errors introduced in the distance estimation using path-loss-based methods has been carried out. Moreover, the exploitation...

Thoracic epidural anesthesia attenuates hemorrhagic-induced splanchnic hypo-perfusion in post-resuscitation experimental hemorrhagic shock

Directory of Open Access Journals (Sweden)

Amir S Madjid

2008-06-01

Full Text Available The purpose of present study was to assess the effects of thoracic epidural anesthesia on splanchnic perfusion, bacterial translocation and histopathologic changes in experimental hemorrhagic shock in short-tailed macaques (Macaca nemestrina. Sixteen Macaca nemestrinas were randomly assigned to one of two groups i.e. the lidocaine group (n = 8, receiving general anesthesia plus lidocaine thoracic epidural anesthesia; and the saline group (n = 8, receiving general anesthesia alone as control. Hemorrhagic shock was induced by withdrawing blood gradually to a mean arterial pressure (MAP of 40 mm Hg, and maintained for 60 minutes. Animals were then resuscitated with their own blood and ringer lactate solution (RL. After resuscitation, epidural lidocaine 2% was given in the lidocaine group and saline in the control group. Resuscitation that was performed after one hour hemorrhagic shock, with hemodynamic variables and urine output returned to normal, revealed there was no improvement of splanchnic perfusion. PgCO2, P(g-aCO2, and pHi remained in critical value and tended to deteriorate in the saline group. Contrast to saline group, splanchnic perfusion in lidocaine group tended to improve. This condition was supported by the finding of less bacterial translocation and better histopathologic changes in lidocaine thoracic epidural anesthesia group than in saline group. This study concludes that lidocaine thoracic epidural anesthesia attenuates splachnic hypoperfusion in post-resuscitation hemorrhagic shock in Macaca nemestrina. (Med J Indones 2008; 17: 73-81Keywords: thoracic epidural anesthesia, lidocaine, hemorrhagic shock, splanchnic hypoperfusion, bacterial translocation

Osteoarticular Expression of Musashi-1 in an Experimental Model of Arthritis

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Francisco O’Valle

2015-01-01

Full Text Available Background. Collagen-induced arthritis (CIA, a murine experimental disease model induced by immunization with type II collagen (CII, is used to evaluate novel therapeutic strategies for rheumatoid arthritis. Adult stem cell marker Musashi-1 (Msi1 plays an important role in regulating the maintenance and differentiation of stem/precursor cells. The objectives of this investigation were to perform a morphological study of the experimental CIA model, evaluate the effect of TNFα-blocker (etanercept treatment, and determine the immunohistochemical expression of Msi1 protein. Methods. CIA was induced in 50 male DBA1/J mice for analyses of tissue and serum cytokine; clinical and morphological lesions in limbs; and immunohistochemical expression of Msi1. Results. Clinically, TNFα-blocker treatment attenuated CIA on day 32 after immunization (P<0.001. Msi1 protein expression was significantly higher in joints damaged by CIA than in those with no lesions (P<0.0001 and was related to the severity of the lesions (Spearman’s rho = 0.775, P=0.0001. Conclusions. Treatment with etanercept attenuates osteoarticular lesions in the murine CIA model. Osteoarticular expression of Msi1 protein is increased in joints with CIA-induced lesion and absent in nonlesioned joints, suggesting that this protein is expressed when the lesion is produced in order to favor tissue repair.

Experimental characterization of resistive joints for use inside ATLAS toroids

CERN Document Server

Volpini, G; Pojer, M

2001-01-01

The authors have investigated, both experimentally and theoretically, the thermo-electrical behavior of the ATLAS magnets resistive joints. These magnets exploit an Al-clad NbTi Rutherford superconducting cable, and the splices between different sections are performed by TIG-welding the Al matrices of the two cables to be connected. This technique is simple from a construction point of view, and we have shown that its performance is adequate for a safe operation of the magnets. The two main concerns during the design of these joints are the temperature rise due to Joule dissipation and the eddy currents induced under nonstationary conditions. We have devised a reliable model of these joints, that allows estimating their resistances and the induced eddy currents; later we have built and measured several sample joints to give experimental confirmation. The model requires, along with the joint geometry, the knowledge of the Rutherford-matrix interface resistance as well as the RRR of the aluminum matrix. In this...

Pathological and MRI study on experimental heroin-induced brain damage in rats

International Nuclear Information System (INIS)

Long Yu; Kong Xiangquan; Xu Haibo; Liu Dingxi; Yuan Ren; Yu Qun; Xiong Yin; Deng Xianbo

2005-01-01

Objective: To study the pathological characteristics of the heroin-induced brain damage in rats, and to assess the diagnostic value of MRI. Methods: A total of 40 adult Wistar rats were studied, 32 rats were used for injecting heroin as heroin group and 8 were used for injecting saline as control group. The heroin dependent rat model was established by administering heroin (ip) in the ascending dosage schedule (0.5 mg/kg), three times a day (at 8:00, 12:00, and 18:00). The control group was established by the same way by injection with saline. The withdrawal scores were evaluated with imp roved criterion in order to estimate the degree of addiction after administering naloxone. Based on the rat model of heroin dependence, the rat model of heroin-induced brain damage was established by the same way with increasing heroin dosage everyday. Two groups were examined by using MRI, light microscope, and electron microscope, respectively in different heroin accumulated dosage (918, 1580, 2686, 3064, 4336, and 4336 mg/kg withdrawal after 2 weeks). Results: There was statistically significant difference (t=9.737, P<0.01) of the withdrawal scores between the heroin dependent group and the saline group (23.0 ± 4.4 and 1.4 ± 0.5, respectively). It suggested that the heroin dependent rat model be established successfully. In different accumulated dosage ( from 1580 mg/kg to 4336 mg/kg), there were degeneration and death of nerve cells in cerebrum and cerebellum of heroin intoxicated rats, and it suggested that the rat model of heroin-induced brain damage was established successfully. The light microscope and electron microscope features of heroin-induced brain damage in rats included: (1) The nerve cells of cerebral cortex degenerated and died. According to the heroin accumulated dosage, there were statistically significant difference of the nerve cell deaths between 4336 mg/kg group and 1580 mg/kg group or control group (P=0.024 and P=0.032, respectively); (2) The main

Research on Hygiene Based on Fieldwork and Experimental Studies.

Science.gov (United States)

Yajima, Ichiro

2017-01-01

Several experimental studies on hygiene have recently been performed and fieldwork studies are also important and essential tools. However, the implementation of experimental studies is insufficient compared with that of fieldwork studies on hygiene. Here, we show our well-balanced implementation of both fieldwork and experimental studies of toxic-element-mediated diseases including skin cancer and hearing loss. Since the pollution of drinking well water by toxic elements induces various diseases including skin cancer, we performed both fieldwork and experimental studies to determine the levels of toxic elements and the mechanisms behind the development of toxic-element-related diseases and to develop a novel remediation system. Our fieldwork studies in several countries including Bangladesh, Vietnam and Malaysia demonstrated that drinking well water was polluted with high concentrations of several toxic elements including arsenic, barium, iron and manganese. Our experimental studies using the data from our fieldwork studies demonstrated that these toxic elements caused skin cancer and hearing loss. Further experimental studies resulted in the development of a novel remediation system that adsorbs toxic elements from polluted drinking water. A well-balanced implementation of both fieldwork and experimental studies is important for the prediction, prevention and therapy of toxic-element-mediated diseases.

Room temperature thin foil SLIM-cut using an epoxy paste: experimental versus theoretical results

International Nuclear Information System (INIS)

Bellanger, Pierre; Serra, Joao; Bouchard, Pierre-Olivier; Bernacki, Marc

2015-01-01

The stress induced lift-off method (SLIM) -cut technique allows the detachment of thin silicon foils using a stress inducing layer. In this work, results of SLIM-cut foils obtained using an epoxy stress inducing layer at room temperature are presented. Numerical analyses were performed in order to study and ascertain the important experimental parameters. The experimental and simulation results are in good agreement. Indeed, large area (5 × 5 cm 2 ) foils were successfully detached at room temperature using an epoxy thickness of 900 μm and a curing temperature of 150 °C. Moreover, three foils (5 × 3 cm 2 ) with thickness 135, 121 and 110 μm were detached from the same monocrystalline substrate. Effective minority carrier lifetimes of 46, 25 and 20 μs were measured using quasi-steady-state photoconductance technique in these foils after iodine ethanol surface passivation. (paper)

Alpha-fetoprotein is present in the fetal fluids and is increased in plasma of mares with experimentally induced ascending placentitis.

Science.gov (United States)

Canisso, Igor F; Ball, Barry A; Scoggin, Kirsten E; Squires, Edward L; Williams, Neil M; Troedsson, Mats H

2015-03-01

The objectives of this study were to: (i) determine alpha-fetoprotein (AFP) concentrations in fetal fluids (FF), and (ii) compare plasma concentrations of AFP in mares with placentitis (n=17) and gestationally age-matched control mares (n=17). Fetal fluid sampling (FFS, n=7/group) was performed at 0, 5 and 12 days post inoculation (DPI) or until abortion. Plasma was harvested daily for 12 days or until abortion. Placentitis was induced via intracervical inoculation of Streptococcus equi ssp. zooepidemicus. Proteins present in the FF were resolved by 1D-SDS-PAGE, and immunoblotting was used to detect the presence of AFP in fetal fluids. Concentrations of AFP in FF and plasma were determined with a chemiluminescence immunoassay. Mixed models for DPI, and for days from abortion (DFA) were used to analyze plasma concentrations of AFP. A protein band ∼68kDa consistent with the AFP size was present in all samples of fetal fluids examined. Immunoblotting for AFP revealed a single protein band (∼68kDa) in all samples. Concentrations of AFP in FF appeared higher than those in maternal plasma. There were effects of time (DPI p<0.0001; DFA p=0.0002) and time-by-group interactions (DPI*Group p<0.06; Group*DFA p<0.001). This study confirmed that AFP is present in the FF of mares during the third trimester of pregnancy. Experimentally induced placentitis was associated with an elevation in maternal plasma concentrations of AFP. Copyright © 2015 Elsevier B.V. All rights reserved.

Psychoimmunomodulating activity of Phenibut under conditions of experimental hyperthyroidism

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M A Samotrueva

2012-03-01

Full Text Available Psychoimmunomodulating action of Phenibut has been shown on the model of experimental hyperthyroidism. It has been found that the drug (intra-abdominal injection in the dose 25 mg/kg is able to restore humoral immunoreactivity and liquidate disturbances of the behaviour reactions appearing in the result of induced pathology as well.

Experimental animal data and modeling of late somatic effects

International Nuclear Information System (INIS)

Fry, R.J.M.

1988-01-01

This section is restricted to radiation-induced life shortening and cancer and mainly to studies with external radiation. The emphasis will be on the experimental data that are available and the experimental systems that could provide the type of data with which to either formulate or test models. Genetic effects which are of concern are not discussed in this section. Experimental animal radiation studies fall into those that establish general principles and those that demonstrate mechanisms. General principles include the influence of dose, radiation quality, dose rate, fractionation, protraction and such biological factors as age and gender. The influence of these factors are considered as general principles because they are independent, at least qualitatively, of the species studied. For example, if an increase in the LET of the radiation causes an increased effectiveness in cancer induction in a mouse a comparable increase in effectiveness can be expected in humans. Thus, models, whether empirical or mechanistic, formulated from experimental animal data should be generally applicable

Analysis of friction-induced limit cycling in an experimental drill-string system

NARCIS (Netherlands)

Mihajlovic, N.; Veggel, van A.A.; Wouw, van de N.; Nijmeijer, H.

2004-01-01

In this paper, we aim for an improved understanding of the causes for torsional vibrations that appear in rotary drilling systems used for the exploration of oil and gas. For this purpose, an experimental drill-string setup is considered. In that system, torsional vibrations with and without

Anti-inflammatory effects of jojoba liquid wax in experimental models.

Science.gov (United States)

Habashy, Ramy R; Abdel-Naim, Ashraf B; Khalifa, Amani E; Al-Azizi, Mohammed M

2005-02-01

Jojoba [Simmondsia chinensis (Link 1822) Schneider 1907] is an arid perennial shrub grown in several American and African countries. Jojoba seeds, which are rich in liquid wax, were used in folk medicine for diverse ailments. In the current study, the potential anti-inflammatory activity of jojoba liquid wax (JLW) was evaluated in a number of experimental models. Results showed that JLW caused reduction of carrageenin-induced rat paw oedema in addition to diminishing prostaglandin E2 (PGE2) level in the inflammatory exudates. In a test for anti-inflammatory potential utilizing the chick's embryo chroioallantoic membrane (CAM), JLW also caused significant lowering of granulation tissue formation. Topical application of JLW reduced ear oedema induced by croton oil in rats. In the same animal model, JLW also reduced neutrophil infiltration, as indicated by decreased myeloperoxidase (MPO) activity. In addition, JLW ameliorated histopathological changes affected by croton oil application. In the lipopolysaccharide (LPS)-induced inflammation in air pouch in rats, JLW reduced nitric oxide (NO) level and tumor necrosis factor-alpha (TNF-alpha) release. In conclusion, this study demonstrates the effectiveness of JLW in combating inflammation in several experimental models. Further investigations are needed to identify the active constituents responsible for the anti-inflammatory property of JLW.

The nature and principles of the radiation-induced cancerogenesis

International Nuclear Information System (INIS)

Lips'ka, A.YI.; Serkyiz, Ya.Yi.

2004-01-01

The paper represents the analysis of the authors and literary data concerning the nature and principles of the radiation-induced neoplasms. The mechanisms of the radiation-induced cancerogenesis development are not clear understood. The experimental data altogether do not allow developing the mathematical model of the radiation-induced cancerogenesis at the molecular level. This model has to take into account all necessary indices including radiation factor and the state of the organism. The general principles of the radiation-induced cancerogenesis have been formulated in the present review. It is possible to use these principles in order to predict and calculate the risks of the radiation-induced neoplasms

Blood concentrations of the cytokines IL-1beta, IL-6, IL-10, TNF-alpha and IFN-gamma during experimentally induced swine dysentery

Directory of Open Access Journals (Sweden)

Jensen-Waern Marianne

2008-08-01

Full Text Available Abstract Background Knowledge of the cytokine response at infection with Brachyspira hyodysenteriae can help understanding disease mechanisme involved during swine dysentery. Since this knowledge is still limited the aim of the present study was to induce dysentery experimentally in pigs and to monitor the development of important immunoregulatory cytokines in blood collected at various stages of the disease. Methods Ten conventional pigs (~23 kg were orally inoculated with Brachyspira hyodysenteriae B204T. Eight animals developed muco-haemorrhagic diarrhoea with impaired general body condition. Blood was sampled before inoculation and repeatedly during acute dysentery and recovery periods and cytokine levels of IL-1β, IL-6, Il-10, TNF-α and IFN-γ were measured by ELISA. Results IL-1β was increased at the beginning of the dysentery period and coincided with the appearance of Serum amyloid A and clinical signs of disease. TNF-α increased in all animals after inoculation, with a peak during dysentery, and IL-6 was found in 3 animals during dysentery and in the 2 animals that did not develop clinical signs of disease. IL-10 was found in all sick animals during the recovery period. IFN-γ was not detected on any occasion. Conclusion B. hyodysenteriae inoculation induced production of systemic levels of IL-1β during the dysentery period and increased levels of IL-10 coincided with recovery from dysentery.

Neuronal involvement in cisplatin neuropathy

DEFF Research Database (Denmark)

Krarup-Hansen, A; Helweg-Larsen, Susanne Elisabeth; Schmalbruch, H

2007-01-01

of large dorsal root ganglion cells. Motor conduction studies, autonomic function and warm and cold temperature sensation remained unchanged at all doses of cisplatin treatment. The results of these studies are consistent with degeneration of large sensory neurons whereas there was no evidence of distal......Although it is well known that cisplatin causes a sensory neuropathy, the primary site of involvement is not established. The clinical symptoms localized in a stocking-glove distribution may be explained by a length dependent neuronopathy or by a distal axonopathy. To study whether the whole neuron...

Converging cellular themes for the hereditary spastic paraplegias.

Science.gov (United States)

Blackstone, Craig

2018-05-10

Hereditary spastic paraplegias (HSPs) are neurologic disorders characterized by prominent lower-extremity spasticity, resulting from a length-dependent axonopathy of corticospinal upper motor neurons. They are among the most genetically-diverse neurologic disorders, with >80 distinct genetic loci and over 60 identified genes. Studies investigating the molecular pathogenesis underlying HSPs have emphasized the importance of converging cellular pathogenic themes in the most common forms of HSP, providing compelling targets for therapy. Most notably, these include organelle shaping and biogenesis as well as membrane and cargo trafficking. Published by Elsevier Ltd.

Neuronal involvement in cisplatin neuropathy

DEFF Research Database (Denmark)

Krarup-Hansen, A; Helweg-Larsen, Susanne Elisabeth; Schmalbruch, H

2007-01-01

Although it is well known that cisplatin causes a sensory neuropathy, the primary site of involvement is not established. The clinical symptoms localized in a stocking-glove distribution may be explained by a length dependent neuronopathy or by a distal axonopathy. To study whether the whole neuron...... of the foot evoked by a tactile probe showed similar changes to those observed in SNAPs evoked by electrical stimulation. At these doses, somatosensory evoked potentials (SEPs) from the tibial nerve had increased latencies of peripheral, spinal and central responses suggesting loss of central processes...

Induced γ emission for nuclear isomer long-lived

International Nuclear Information System (INIS)

Yang Tianli; Hao Fanhua

2007-06-01

It is pointed that the induced 7 emission for long lived isomer 178m2 Hf by low energy X rays has been a topic subject in the nuclear field recently. The background and development status are described. A principle for T ray transitions induced by X rays and the theoretical about magnificent induced emission have been related. In addition, the possible method of 178m2 Hf produce has been introduced also. Although the argument has existed for the experimental results of induced 7 emission, it can push forward in solving energy crisis and in future military field after controlling effectively the releasing of high excited energy for isomer. (authors)

LHC experimental sensitivity to CP violating gtt couplings

CERN Document Server

Sjölin, J

2003-01-01

The level of CP violation in pp to tt+X induced by the standard model is known to be below the experimental sensitivity by many orders of magnitude. However, in some effective theories, it is plausible that new CP violating physics could reveal itself as additional non- renormalizable terms in the Lagrangian. Since these should respect the symmetries of the low-energy gauge interaction, violate CP and generate the correct event topology, the set of allowed terms is highly restricted. This analysis gives an estimate of the expected experimental sensitivity to the lowest order effective CP violating gtt interaction term beyond the standard model using simulated data from the ATLAS detector at the LHC. (36 refs).

PTEN gene and phosphorylation of Akt protein expression in the LPS-induced lung fibroblast

Directory of Open Access Journals (Sweden)

Mao-lin HUANG

2014-09-01

Full Text Available Objective: To investigate PTEN gene expression and the Akt phosphorylation of protein expression in the LPS-induced lung fibroblast, to initially reveal the relation between PTEN gene and the Akt phosphorylated proteins to LPS-induced lung fibroblast proliferation mechanism. Methods: BrdU experiments was performed to evaluate the LPS-induced lung fibroblast proliferation,  RT-PCR and Western Blot analysis were used to analyze the PTEN gene expression and Western blot was performed to analyze Akt phosphorylated protein expression. Results: PTEN mRNA level of the experimental group were significantly lower than the control group (P<0.05 with LPS simulation for 24h and 72h , and there were no significant difference between the experimental group and control group the experimental group and control group (P>0.05 . PTEN protein expression levels of the experimental group were significantly lower than the control group (P<0.05 , at 72h, and PTEN mRNA levels had no significant differences between these of the experimental and control group at 6h,12h and 24h(p>0.05. Phosphorylation Akt protein level (relative to total Akt protein was significantly higer than the control group (P<0.05 at 24h and 72h, and phosphorylation Akt protein levels had no significant differences between these of the experimental and control group at 6h and 12h (P>0.05 .Conclusion: PTEN gene and phosphorylation Akt protein involve in LPS-induced lung fibroblast proliferation signal transduction pathway.

Periodontal CGRP contributes to orofacial pain following experimental tooth movement in rats.

Science.gov (United States)

Long, Hu; Liao, Lina; Gao, Meiya; Ma, Wenqiang; Zhou, Yang; Jian, Fan; Wang, Yan; Lai, Wenli

2015-08-01

Calcitonin-related gene peptide (CGRP) plays an important role in orofacial inflammatory pain. The aim of this study was to determine whether periodontal CGRP contributes to orofacial pain induced by experimental tooth movement in rats. Male Sprague-Dawley rats were used in this study. Closed coil springs were used to deliver forces. Rats were euthanized on 0d, 1d, 3d, 5d, 7d, and 14d following experimental tooth movement. Then, alveolar bones were obtained for immunostaining of periodontal tissues against CGRP. Two hours prior to euthanasia on each day, orofacial pain levels were assessed through rat grimace scale. CGRP and olcegepant (CGRP receptor antagonist) were injected into periodontal tissues to verify the roles of periodontal CGRP in orofacial pain induced by experimental tooth movement. Periodontal CGRP expression levels and orofacial pain levels were elevated on 1d, 3d, 5d, and 7d following experimental tooth movement. The two indices were significantly correlated with each other and fitted into a dose-response model. Periodontal administration of CGRP could elevate periodontal CGRP expressions and exacerbate orofacial pain. Moreover, olcegepant administration could decrease periodontal CGRP expressions and alleviate orofacial pain. Therefore, periodontal CGRP plays an important role in pain transmission and modulation following experimental tooth movement. We suggest that it may participate in a positive feedback aiming to amplify orofacial pain signals. Copyright © 2015 Elsevier B.V. All rights reserved.

Chondromalacia induced by patellar subluxation in the rabbit

DEFF Research Database (Denmark)

Møller, B.N.; Møller-Larsen, F.; Frich, Lars Henrik

1989-01-01

A unilateral patellar malalignment was induced in 20 young and 20 mature rabbits by lateral displacement of the tibial tuberosity, the other knee serving as osteotomized in situ control. At 6 weeks, all the knees appeared macroscopically normal, but histologically definite cartilage degeneration...... was found on the experimental side. At 3 months, macroscopic changes occurred in 5 of 10 mature rabbits, and histologic cartilage degeneration was found in all the experimental knees, most pronounced in mature animals, and particularly in joint facets submitted to high pressure. This experimental model...

Molecular and cellular mechanisms of vitamin D3 protection in experimental prednisolone-induced osteoporosis

Directory of Open Access Journals (Sweden)

I.O. Shymanskyi

2017-08-01

Full Text Available Background. Osteoporosis is the most common side effect of glucocorticoid (GC therapy. Vitamin D is known to play a crucial role in bone remodeling, but the precise molecular mechanisms of its action on GC-induced impairments of cytokine systems, in particular RANK (receptor activator of nuclear factor kappa-B/RANKL (RANK ligand/OPG (osteoprotegerin, are still controversial. Thus, the purpose of the study was to evaluate GC-induced changes in the RANK/RANKL/OPG system and osteocalcin synthesis in rat bone depending on vitamin D bioavailability and vitamin D receptor (VDR expression. Materials and methods. Female Wistar rats received prednisolone (5 mg/kg b.w. with or without 100 IU of vitamin D3 (for 30 days. The levels of VDR, osteocalcin, RANK, RANKL and OPG in bone tissue were determined by western blotting. Blood serum 25OHD was assayed by enzyme-linked immunosorbent assay. The levels of Ca2+, Pi, activity of alkaline phosphatase (AP and its bone isoenzyme were determined using spectrophotometry. Results. Prednisolone significantly lowered 25OHD content in the blood serum and VDR level in bone tissue that has been accompanied by an elevation of the AP bone isoenzyme activity in the blood serum, hypocalcemia and hypophosphatemia. A significant decrease in the expression of osteocalcin, a well-known marker of bone formation, was also observed. GC-induced disturbances in vitamin D status led to a reduction of the RANK and OPG level, while RANKL level was unaffected. Vitamin D3 administration restored 25OHD and VDR levels that resulted in amelioration of GC-induced changes in bone tissue and normalization of mineral metabolism through elevation of RANK, OPG and osteocalcin levels. Conclusions. Prednisolone-induced imbalance in the RANK/RANKL/OPG and osteocalcin systems is related to the reduction of vitamin D bioavailability and impairments in VDR signaling. Thus, normalization of vitamin D bioavailability might be perspective in reducing the