Science.gov

Sample records for experimentally induced dyspnea

  1. Sinusitis and chronic progressive exercise-induced cough and dyspnea.

    PubMed

    Williams, Adam N; Simon, Ronald A; Woessner, Katharine M

    2008-01-01

    We present the case of a 47-year-old man with exercise-induced dyspnea, cough, chest tightness, and recalcitrant chronic rhinosinusitis. Evaluation revealed IgE sensitization to grass, tree, and weed pollen, no evidence of obstruction on spirometry, and a negative methacholine challenge. Diagnostic considerations included allergic and nonallergic rhinitis, asthma, aspirin-exacerbated respiratory disease, vocal cord dysfunction, extra-esophageal manifestations of acid reflux, and vasculitits. Further evaluation with sinus imaging, laryngoscopy, ambulatory pharyngeal pH testing, upper endoscopy, and bronchoscopy led to a diagnosis. Key issues surrounding the diagnostic and therapeutic approaches to this patient's condition are reviewed.

  2. Interactions Between Dyspnea and the Brain Processing of Nociceptive Stimuli: Experimental Air Hunger Attenuates Laser-Evoked Brain Potentials in Humans

    PubMed Central

    Dangers, Laurence; Laviolette, Louis; Similowski, Thomas; Morélot-Panzini, Capucine

    2015-01-01

    Dyspnea and pain share several characteristics and certain neural networks and interact with each other. Dyspnea-pain counter-irritation consists of attenuation of preexisting pain by intercurrent dyspnea and has been shown to have neurophysiological correlates in the form of inhibition of the nociceptive spinal reflex RIII and laser-evoked potentials (LEPs). Experimentally induced exertional dyspnea inhibits RIII and LEPs, while “air hunger” dyspnea does not inhibit RIII despite its documented analgesic effects. We hypothesized that air hunger may act centrally and inhibit LEPs. LEPs were obtained in 12 healthy volunteers (age: 21–29) during spontaneous breathing (FB), ventilator-controlled breathing (VC) tailored to FB, after inducing air hunger by increasing the inspired fraction of carbon dioxide -FiCO2- (VCCO2), and during ventilator-controlled breathing recovery (VCR). VCCO2 induced intense dyspnea (visual analog scale = 63% ± 6% of full scale, p < 0.001 vs. VC), predominantly of the air hunger type. VC alone reduced the amplitude of the N2-P2 component of LEPs (Δ = 24.0% ± 21.1%, p < 0.05, effect-size = 0.74) predominantly through a reduction in P2, and the amplitude of this inhibition was further reduced by inducting air hunger (Δ = 22.6% ± 17.9%, p < 0.05, effect-size = 0.53), predominantly through a reduction in N2. Somatosensory-evoked potentials (SEPs) were not affected by VC or VCCO2, suggesting that the observed effects are specific to pain transmission. We conclude that air hunger interferes with the cortical mechanisms responsible for the cortical response to painful laser skin stimulation, which provides a neurophysiological substrate to the central nature of its otherwise documented analgesic effects. PMID:26648875

  3. Interactions Between Dyspnea and the Brain Processing of Nociceptive Stimuli: Experimental Air Hunger Attenuates Laser-Evoked Brain Potentials in Humans.

    PubMed

    Dangers, Laurence; Laviolette, Louis; Similowski, Thomas; Morélot-Panzini, Capucine

    2015-01-01

    Dyspnea and pain share several characteristics and certain neural networks and interact with each other. Dyspnea-pain counter-irritation consists of attenuation of preexisting pain by intercurrent dyspnea and has been shown to have neurophysiological correlates in the form of inhibition of the nociceptive spinal reflex RIII and laser-evoked potentials (LEPs). Experimentally induced exertional dyspnea inhibits RIII and LEPs, while "air hunger" dyspnea does not inhibit RIII despite its documented analgesic effects. We hypothesized that air hunger may act centrally and inhibit LEPs. LEPs were obtained in 12 healthy volunteers (age: 21-29) during spontaneous breathing (FB), ventilator-controlled breathing (VC) tailored to FB, after inducing air hunger by increasing the inspired fraction of carbon dioxide -FiCO2- (VCCO2), and during ventilator-controlled breathing recovery (VCR). VCCO2 induced intense dyspnea (visual analog scale = 63% ± 6% of full scale, p < 0.001 vs. VC), predominantly of the air hunger type. VC alone reduced the amplitude of the N2-P2 component of LEPs (Δ = 24.0% ± 21.1%, p < 0.05, effect-size = 0.74) predominantly through a reduction in P2, and the amplitude of this inhibition was further reduced by inducting air hunger (Δ = 22.6% ± 17.9%, p < 0.05, effect-size = 0.53), predominantly through a reduction in N2. Somatosensory-evoked potentials (SEPs) were not affected by VC or VCCO2, suggesting that the observed effects are specific to pain transmission. We conclude that air hunger interferes with the cortical mechanisms responsible for the cortical response to painful laser skin stimulation, which provides a neurophysiological substrate to the central nature of its otherwise documented analgesic effects. PMID:26648875

  4. [Dyspnea and behavioral control].

    PubMed

    Chonan, T

    1992-04-01

    Respiration is automatically regulated via chemo- and mechanoreceptors existing in and outside the lungs, but it is also controlled voluntarily by behavioral factors. Voluntary increase in ventilation accentuates dyspnea and the sensory intensity at a given ventilation does not differ from that of exercise-induced hyperventilation, but it is significantly smaller than that during hypercapnia or hypoxia. Voluntary constraint of ventilation augments dyspnea in proportion to the degree of constraint even under isocapnic hyperoxia, and the respiratory sensation during constrained breathing is qualitatively more discomfortable than that during hyperventilation. Changes in the level and pattern of breathing under constant levels of chemical stimuli increase respiratory sensations and the intensity of dyspnea is minimal near the spontaneous levels, which supports the hypothesis that breathing is behaviorally regulated in part to minimize dyspnea. The system of behavioral control of breathing appears to be involved in the maintenance of body homeostasis by modifying the respiratory output through respiratory sensations.

  5. Brain Responses during the Anticipation of Dyspnea.

    PubMed

    Stoeckel, M Cornelia; Esser, Roland W; Gamer, Matthias; Büchel, Christian; von Leupoldt, Andreas

    2016-01-01

    Dyspnea is common in many cardiorespiratory diseases. Already the anticipation of this aversive symptom elicits fear in many patients resulting in unfavorable health behaviors such as activity avoidance and sedentary lifestyle. This study investigated brain mechanisms underlying these anticipatory processes. We induced dyspnea using resistive-load breathing in healthy subjects during functional magnetic resonance imaging. Blocks of severe and mild dyspnea alternated, each preceded by anticipation periods. Severe dyspnea activated a network of sensorimotor, cerebellar, and limbic areas. The left insular, parietal opercular, and cerebellar cortices showed increased activation already during dyspnea anticipation. Left insular and parietal opercular cortex showed increased connectivity with right insular and anterior cingulate cortex when severe dyspnea was anticipated, while the cerebellum showed increased connectivity with the amygdala. Notably, insular activation during dyspnea perception was positively correlated with midbrain activation during anticipation. Moreover, anticipatory fear was positively correlated with anticipatory activation in right insular and anterior cingulate cortex. The results demonstrate that dyspnea anticipation activates brain areas involved in dyspnea perception. The involvement of emotion-related areas such as insula, anterior cingulate cortex, and amygdala during dyspnea anticipation most likely reflects anticipatory fear and might underlie the development of unfavorable health behaviors in patients suffering from dyspnea. PMID:27648309

  6. Brain Responses during the Anticipation of Dyspnea

    PubMed Central

    Stoeckel, M. Cornelia; Esser, Roland W.; Büchel, Christian

    2016-01-01

    Dyspnea is common in many cardiorespiratory diseases. Already the anticipation of this aversive symptom elicits fear in many patients resulting in unfavorable health behaviors such as activity avoidance and sedentary lifestyle. This study investigated brain mechanisms underlying these anticipatory processes. We induced dyspnea using resistive-load breathing in healthy subjects during functional magnetic resonance imaging. Blocks of severe and mild dyspnea alternated, each preceded by anticipation periods. Severe dyspnea activated a network of sensorimotor, cerebellar, and limbic areas. The left insular, parietal opercular, and cerebellar cortices showed increased activation already during dyspnea anticipation. Left insular and parietal opercular cortex showed increased connectivity with right insular and anterior cingulate cortex when severe dyspnea was anticipated, while the cerebellum showed increased connectivity with the amygdala. Notably, insular activation during dyspnea perception was positively correlated with midbrain activation during anticipation. Moreover, anticipatory fear was positively correlated with anticipatory activation in right insular and anterior cingulate cortex. The results demonstrate that dyspnea anticipation activates brain areas involved in dyspnea perception. The involvement of emotion-related areas such as insula, anterior cingulate cortex, and amygdala during dyspnea anticipation most likely reflects anticipatory fear and might underlie the development of unfavorable health behaviors in patients suffering from dyspnea.

  7. Brain Responses during the Anticipation of Dyspnea

    PubMed Central

    Stoeckel, M. Cornelia; Esser, Roland W.; Büchel, Christian

    2016-01-01

    Dyspnea is common in many cardiorespiratory diseases. Already the anticipation of this aversive symptom elicits fear in many patients resulting in unfavorable health behaviors such as activity avoidance and sedentary lifestyle. This study investigated brain mechanisms underlying these anticipatory processes. We induced dyspnea using resistive-load breathing in healthy subjects during functional magnetic resonance imaging. Blocks of severe and mild dyspnea alternated, each preceded by anticipation periods. Severe dyspnea activated a network of sensorimotor, cerebellar, and limbic areas. The left insular, parietal opercular, and cerebellar cortices showed increased activation already during dyspnea anticipation. Left insular and parietal opercular cortex showed increased connectivity with right insular and anterior cingulate cortex when severe dyspnea was anticipated, while the cerebellum showed increased connectivity with the amygdala. Notably, insular activation during dyspnea perception was positively correlated with midbrain activation during anticipation. Moreover, anticipatory fear was positively correlated with anticipatory activation in right insular and anterior cingulate cortex. The results demonstrate that dyspnea anticipation activates brain areas involved in dyspnea perception. The involvement of emotion-related areas such as insula, anterior cingulate cortex, and amygdala during dyspnea anticipation most likely reflects anticipatory fear and might underlie the development of unfavorable health behaviors in patients suffering from dyspnea. PMID:27648309

  8. Marathon-induced pulmonary edema of a patient with transient dyspnea.

    PubMed

    Miyazawa, Ryo; Morita, Yuka; Okajima, Yuka; Matsusako, Masaki; Kurihara, Yasuyuki

    2015-10-01

    We report a case of a 31-year-old healthy man with marathon-induced pulmonary edema. Chest radiograph revealed pulmonary edema without cardiomegaly. Contrast-enhanced chest computed tomography (CT) revealed transient pulmonary edema without filling-defect in pulmonary arteries. As marathon running increases in popularity, radiologists and emergency physicians should be familiar with diagnosis of this entity on chest radiograph, avoiding unnecessary CT examination without additional clinical information.

  9. Marathon-induced pulmonary edema of a patient with transient dyspnea.

    PubMed

    Miyazawa, Ryo; Morita, Yuka; Okajima, Yuka; Matsusako, Masaki; Kurihara, Yasuyuki

    2015-10-01

    We report a case of a 31-year-old healthy man with marathon-induced pulmonary edema. Chest radiograph revealed pulmonary edema without cardiomegaly. Contrast-enhanced chest computed tomography (CT) revealed transient pulmonary edema without filling-defect in pulmonary arteries. As marathon running increases in popularity, radiologists and emergency physicians should be familiar with diagnosis of this entity on chest radiograph, avoiding unnecessary CT examination without additional clinical information. PMID:26324381

  10. Papain-induced asthma: a man with dyspnea from dawn till dust.

    PubMed

    Goeminne, P C; Adams, E; Deschepper, K; Valcke, Y; Nemery, B

    2013-01-01

    A 52-year-old man, a current smoker (40 pack years) with unremarkable medical history, was referred to the outpatient pneumology clinic because of recent complaints of shortness of breath and wheezing, which were relieved by inhaled bronchodilators. Serial peak expiratory flow (PEF) measurements showed a clear rise in PEF during the weekend and a fall on the evening after the first day of the week. It also showed that evening values were always lower than morning values. During a holiday, a slow but persistent rise in PEF was observed. Such a pattern is highly suggestive for occupational asthma. A detailed description of his job revealed papain exposure. After a positive specific IgE and skin prick test for papain the diagnosis of papain induced asthma was made. When an allergy and serious lung function impairment is proven against products encountered in a work related situation, not improving after maximal preventive measures, the patient is advised to change job. PMID:23967724

  11. Dyspnea in dying patients.

    PubMed Central

    Hsu, D. H.

    1993-01-01

    Dyspnea is common in terminally ill patients and is often fairly difficult to control. If specific causes cannot be identified or treated, general measures to relieve symptoms should be used. Nondrug measures (eg, discussion and explanation with the patient) and drug measures (eg, morphine) can be used to control the dyspnea, although side effects, such as sedation, can be problematic. PMID:8348024

  12. Brain mechanisms of short-term habituation and sensitization toward dyspnea

    PubMed Central

    Stoeckel, M. Cornelia; Esser, Roland W.; Gamer, Matthias; Büchel, Christian; von Leupoldt, Andreas

    2015-01-01

    Dyspnea is a prevalent and threatening cardinal symptom in many diseases including asthma. Whether patients suffering from dyspnea show habituation or sensitization toward repeated experiences of dyspnea is relevant for both quality of life and treatment success. Understanding the mechanisms, including the underlying brain activation patterns, that determine the dynamics of dyspnea perception seems crucial for the improvement of treatment and rehabilitation. Toward this aim, we investigated the interplay between short-term changes of dyspnea perception and changes of related brain activation. Healthy individuals underwent repeated blocks of resistive load induced dyspnea with parallel acquisition of functional magnetic resonance imaging data. Late vs. early ratings on dyspnea intensity and unpleasantness were correlated with late vs. early brain activation for both, dyspnea anticipation and dyspnea perception. Individual trait and state anxiety were determined using questionnaire data. Our results indicate an involvement of the orbitofrontal cortex (OFC), midbrain/periaqueductal gray (PAG) and anterior insular cortex in habituation/sensitization toward dyspnea. Changes in the anterior insular cortex were particularly linked to changes in dyspnea unpleasantness. Changes of both dyspnea intensity and unpleasantness were positively correlated with state and trait anxiety. Our findings are in line with the suggested relationship between the anterior insular cortex and dyspnea unpleasantness. They further support the notion that habituation/sensitization toward dyspnea is influenced by anxiety. Our study extends the known role of the midbrain/PAG in anti-nociception to an additional involvement in habituation/sensitization toward dyspnea and suggests an interplay with the OFC. PMID:26082746

  13. Hospital without dyspnea: rationale and design of a multidisciplinary intervention.

    PubMed

    Vicent, Lourdes; Olarte, Juan Manuel Nuñez; Puente-Maestu, Luis; Artajona, Esther; Fernández-Avilés, Francisco; Martínez-Sellés, Manuel

    2016-07-01

    Dyspnea is a common and disabling symptom of respiratory and heart diseases, which is growing in incidence. During hospital admission, breathlessness is under-diagnosed and under-treated, although there are treatments available for controlling the symptom. We have developed a tailored implementation strategy directed to medical staff to promote the application of these pharmacological and non-pharmacological tools in dealing with dyspnea. The primary aim is to decrease the rate of patients that do not receive an adequate relief of dyspnea. This is a four-stage quasi-experimental study. The intervention consists in two teaching talks that will be taught in Cardiology and Respiratory Medicine Departments. The contents will be prepared by Palliative Care specialists, based on available tools for management of dyspnea and patients' needs. A cross-sectional study of dyspnea in hospitalized patients will be performed before and after the intervention to ascertain an improvement in dyspnea intensity due to changes in medical practices. The last phase consists in the creation of consensus protocols for dyspnea management based in our experience. The results of this study are expected to be of great value and may change clinical practice in the near future and promote a changing for the better of dyspnea care. PMID:27605944

  14. Hospital without dyspnea: rationale and design of a multidisciplinary intervention

    PubMed Central

    Vicent, Lourdes; Olarte, Juan Manuel Nuñez; Puente-Maestu, Luis; Artajona, Esther; Fernández-Avilés, Francisco; Martínez-Sellés, Manuel

    2016-01-01

    Dyspnea is a common and disabling symptom of respiratory and heart diseases, which is growing in incidence. During hospital admission, breathlessness is under-diagnosed and under-treated, although there are treatments available for controlling the symptom. We have developed a tailored implementation strategy directed to medical staff to promote the application of these pharmacological and non-pharmacological tools in dealing with dyspnea. The primary aim is to decrease the rate of patients that do not receive an adequate relief of dyspnea. This is a four-stage quasi-experimental study. The intervention consists in two teaching talks that will be taught in Cardiology and Respiratory Medicine Departments. The contents will be prepared by Palliative Care specialists, based on available tools for management of dyspnea and patients' needs. A cross-sectional study of dyspnea in hospitalized patients will be performed before and after the intervention to ascertain an improvement in dyspnea intensity due to changes in medical practices. The last phase consists in the creation of consensus protocols for dyspnea management based in our experience. The results of this study are expected to be of great value and may change clinical practice in the near future and promote a changing for the better of dyspnea care.

  15. Hospital without dyspnea: rationale and design of a multidisciplinary intervention

    PubMed Central

    Vicent, Lourdes; Olarte, Juan Manuel Nuñez; Puente-Maestu, Luis; Artajona, Esther; Fernández-Avilés, Francisco; Martínez-Sellés, Manuel

    2016-01-01

    Dyspnea is a common and disabling symptom of respiratory and heart diseases, which is growing in incidence. During hospital admission, breathlessness is under-diagnosed and under-treated, although there are treatments available for controlling the symptom. We have developed a tailored implementation strategy directed to medical staff to promote the application of these pharmacological and non-pharmacological tools in dealing with dyspnea. The primary aim is to decrease the rate of patients that do not receive an adequate relief of dyspnea. This is a four-stage quasi-experimental study. The intervention consists in two teaching talks that will be taught in Cardiology and Respiratory Medicine Departments. The contents will be prepared by Palliative Care specialists, based on available tools for management of dyspnea and patients' needs. A cross-sectional study of dyspnea in hospitalized patients will be performed before and after the intervention to ascertain an improvement in dyspnea intensity due to changes in medical practices. The last phase consists in the creation of consensus protocols for dyspnea management based in our experience. The results of this study are expected to be of great value and may change clinical practice in the near future and promote a changing for the better of dyspnea care. PMID:27605944

  16. Acute dyspnea in the office.

    PubMed

    Zoorob, Roger J; Campbell, James S

    2003-11-01

    Respiratory difficulty is a common presenting complaint in the outpatient primary care setting. Because patients may first seek care by calling their physician's office, telephone triage plays a role in the early management of dyspnea. Once the patient is in the office, the initial goal of assessment is to determine the severity of the dyspnea with respect to the need for oxygenation and intubation. Unstable patients typically present with abnormal vital signs, altered mental status, hypoxia, or unstable arrhythmia, and require supplemental oxygen, intravenous access and, possibly, intubation. Subsequent management depends on the differential diagnosis established by a proper history, physical examination, and ancillary studies. Dyspnea is most commonly caused by respiratory and cardiac disorders. Other causes may be upper airway obstruction, metabolic acidosis, a psychogenic disorder, or a neuromuscular condition. Differential diagnoses in children include bronchiolitis, croup, epiglottitis, and foreign body aspiration. Pertinent history findings include cough, sore throat, chest pain, edema, and orthopnea. The physical examination should focus on vital signs and the heart, lungs, neck, and lower extremities. Significant physical signs are fever, rales, wheezing, cyanosis, stridor, or absent breath sounds. Diagnostic work-up includes pulse oximetry, complete blood count, electrocardiography, and chest radiography. If the patient is admitted to the emergency department or hospital, blood gases, ventilation-perfusion scan, D-dimer tests, and spiral computed tomography can help clarify the diagnosis. In a stable patient, management depends on the underlying etiology of the dyspnea.

  17. An Unusual Cause of Dyspnea.

    PubMed

    Grzesik, Peter; Passik, Cary; Mahfoozi, Amirhossein

    2016-10-01

    Sialadenoma papilliferum is a tumor of salivary gland origin. It is believed that sialadenoma papilliferum is a benign lesion usually known to occur in the hard palate, retromolar fat pads, lips, and parotid glands. Its origin in the bronchial tree is an extremely rare occurrence. We report only the fourth known case of bronchial sialadenoma papilliferum and the first to originate in the trachea. The patient underwent successful resection of the lesion, with complete relief of his dyspnea. PMID:27645975

  18. [Palliation of dyspnea in malignant disease].

    PubMed

    de la Fuente Fonnest, I; Hjortshøj, K M; Strömgren, L A

    1999-01-18

    Dyspnea is a symptom experienced by more than half of all cancer patients in their terminal illness, and it is thus a severe problem for patients, relatives, and professionals. Dyspnea in a cancer patient may have a non-malignant origin that may be treated causally. If dyspnea is caused directly by the malignant disease, antineoplastic treatment needs to be considered. In case this is not feasible, one must seek to modify the manifestations of illness. When this is not possible, one must relieve the patient's experience of dyspnea. To this end there are a number of possibilities, pharmacological as well as non-pharmacological. Opioids given systemically cause respiratory depression. Unfortunately, this has given rise to an overly cautious attitude when facing the terminal patient with dyspnea. However, other treatment modalities are often exhausted and opioids, if indicated in combination with anxiolytics, do have a palliative effect on dyspnea.

  19. Causes and evaluation of chronic dyspnea.

    PubMed

    Wahls, Steven A

    2012-07-15

    Chronic dyspnea is shortness of breath that lasts more than one month. The perception of dyspnea varies based on behavioral and physiologic responses. Dyspnea that is greater than expected with the degree of exertion is a symptom of disease. Most cases of dyspnea result from asthma, heart failure and myocardial ischemia, chronic obstructive pulmonary disease, interstitial lung disease, pneumonia, or psychogenic disorders. The etiology of dyspnea is multifactorial in about one-third of patients. The clinical presentation alone is adequate to make a diagnosis in 66 percent of patients with dyspnea. Patients' descriptions of the sensation of dyspnea may be helpful, but associated symptoms and risk factors, such as smoking, chemical exposures, and medication use, should also be considered. Examination findings (e.g., jugular venous distention, decreased breath sounds or wheezing, pleural rub, clubbing) may be helpful in making the diagnosis. Initial testing in patients with chronic dyspnea includes chest radiography, electrocardiography, spirometry, complete blood count, and basic metabolic panel. Measurement of brain natriuretic peptide levels may help exclude heart failure, and D-dimer testing may help rule out pulmonary emboli. Pulmonary function studies can be used to identify emphysema and interstitial lung diseases. Computed tomography of the chest is the most appropriate imaging study for diagnosing suspected pulmonary causes of chronic dyspnea. To diagnose pulmonary arterial hypertension or certain interstitial lung diseases, right heart catheterization or bronchoscopy may be needed. PMID:22962929

  20. Variability of the perception of dyspnea in healthy subjects assessed through inspiratory resistive loading*

    PubMed Central

    Ziegler, Bruna; Fernandes, Andréia Kist; Sanches, Paulo Roberto Stefani; Konzen, Glauco Luís; Dalcin, Paulo de Tarso Roth

    2015-01-01

    Objective: Few studies have evaluated the variability of the perception of dyspnea in healthy subjects. The objective of this study was to evaluate the variability of the perception of dyspnea in healthy subjects during breathing against increasing inspiratory resistive loads, as well as to assess the association between the level of perception of dyspnea and the level of physical activity. Methods: This was a cross-sectional study involving healthy individuals 16 years of age or older. Subjects underwent inspiratory resistive loading testing, in which the level of perception of dyspnea was quantified with the modified Borg scale. We also determined body mass indices (BMIs), assessed maximal respiratory pressures, performed pulmonary function tests, applied the international physical activity questionnaire (IPAQ)-long form, and conducted six-minute walk tests (6MWTs). The level of perception of dyspnea was classified as low (Borg score < 2), intermediate (Borg score, 2-5), or high (Borg score > 5). Results: We included 48 healthy subjects in the study. Forty-two subjects completed the test up to a load of 46.7 cmH2O/L/s. The level of perception of dyspnea was classified as low, intermediate, and high in 13, 19, and 10 subjects, respectively. The level of perception of dyspnea was not significantly associated with age, gender, BMI, IPAQ-long form score, maximal respiratory pressures, or pulmonary function test results. Conclusions: The scores for perceived dyspnea induced by inspiratory resistive loading in healthy subjects presented wide variability. The perception of dyspnea was classified as low in 31% of the subjects, intermediate in 45%, and high in 24%. There was no association between the level of perception of dyspnea and the level of physical activity (IPAQ or six-minute walk distance). PMID:25830380

  1. Exercise dyspnea in patients with COPD.

    PubMed

    Stendardi, Loredana; Binazzi, Barbara; Scano, Giorgio

    2007-01-01

    Dyspnea, a symptom limiting exercise capacity in patients with COPD, is associated with central perception of an overall increase in central respiratory motor output directed preferentially to the rib cage muscles. On the other hand, disparity between respiratory motor output, mechanical and ventilatory response of the system is also thought to play an important role on the increased perception of exercise in these patients. Both inspiratory and expiratory muscles and operational lung volumes are important contributors to exercise dyspnea. However, the potential link between dyspnea, abnormal mechanics of breathing and impaired exercise performance via the circulation rather than a malfunctioning ventilatory pump per se should not be disregarded. Change in arterial blood gas content may affect dyspnea via direct or indirect effects. An increase in carbon dioxide arterial tension seems to be the most important stimulus overriding all other inputs from dyspnea in hypercapnic COPD patients. Hypoxia may act indirectly by increasing ventilation and indirectly independent of changes in ventilation. A greater treatment effect is often achieved after the addition of pulmonary rehabilitation with pharmacological treatment. PMID:18268917

  2. Speaking-Related Dyspnea in Healthy Adults

    ERIC Educational Resources Information Center

    Hoit, Jeannette D.; Lansing, Robert W.; Perona, Kristen E.

    2007-01-01

    Purpose: To reveal the qualities and intensity of speaking-related dyspnea in healthy adults under conditions of high ventilatory drive, in which the behavioral and metabolic control of breathing must compete. Method: Eleven adults read aloud while breathing different levels of inspired carbon dioxide (CO[subscript 2]). After the highest level,…

  3. Mechanical correlates of dyspnea in bronchial asthma

    PubMed Central

    Antonelli, Andrea; Crimi, Emanuele; Gobbi, Alessandro; Torchio, Roberto; Gulotta, Carlo; Dellaca, Raffaele; Scano, Giorgio; Brusasco, Vito; Pellegrino, Riccardo

    2013-01-01

    Abstract We hypothesized that dyspnea and its descriptors, that is, chest tightness, inspiratory effort, unrewarded inspiration, and expiratory difficulty in asthma reflect different mechanisms of airflow obstruction and their perception varies with the severity of bronchoconstriction. Eighty‐three asthmatics were studied before and after inhalation of methacholine doses decreasing the 1‐sec forced expiratory volume by ~15% (mild bronchoconstriction) and ~25% (moderate bronchoconstriction). Symptoms were examined as a function of changes in lung mechanics. Dyspnea increased with the severity of obstruction, mostly because of inspiratory effort and chest tightness. At mild bronchoconstriction, multivariate analysis showed that dyspnea was related to the increase in inspiratory resistance at 5 Hz (R5) (r2 = 0.10, P = 0.004), chest tightness to the decrease in maximal flow at 40% of control forced vital capacity, and the increase in R5 at full lung inflation (r2 = 0.15, P = 0.006), inspiratory effort to the temporal variability in R5‐19 (r2 = 0.13, P = 0.003), and unrewarded inspiration to the recovery of R5 after deep breath (r2 = 0.07, P = 0.01). At moderate bronchoconstriction, multivariate analysis showed that dyspnea and inspiratory effort were related to the increase in temporal variability in inspiratory reactance at 5 Hz (X5) (r2 = 0.12, P = 0.04 and r2 = 0.18, P < 0.001, respectively), and unrewarded inspiration to the decrease in X5 at maximum lung inflation (r2 = 0.07, P = 0.04). We conclude that symptom perception is partly explained by indexes of airway narrowing and loss of bronchodilatation with deep breath at low levels of bronchoconstriction, but by markers of ventilation heterogeneity and lung volume recruitment when bronchoconstriction becomes more severe. PMID:24744853

  4. [A rare cause of dyspnea on exertion].

    PubMed

    Maccari, Uberto; Rosini, Costanza F; Scala, Raffaele; Magnolfi, Anna Lisa; Felici, Massimo; Bolognese, Leonardo

    2016-01-01

    Vascular rings are rare anomalies accounting for 1% to 3% of all congenital heart diseases with a similar frequency in both sexes, which can result in a variable degree of extrinsic compression of the trachea and esophagus. We report the case of a 46-year-old woman with symptomatic dyspnea and double aortic arch that caused esophageal tracheal compression. Considering the little impact of the functional vascular anomaly in our case, a conservative approach was adopted with clinical and functional annual follow-up. PMID:26901260

  5. Induction of dyspnea evokes increased anxiety and maladaptive breathing in individuals with high anxiety sensitivity and suffocation fear.

    PubMed

    Alius, Manuela G; Pané-Farré, Christiane A; Von Leupoldt, Andreas; Hamm, Alfons O

    2013-05-01

    Although respiratory symptoms are relevant for diagnosis and etiology of panic disorder, anxiety responses and breathing behavior evoked by induction of dyspnea have rarely been studied. Therefore, dyspnea sensations and affective evaluations evoked by inspiratory resistive loads of different intensities were first assessed in 23 individuals with high versus 24 participants with low anxiety sensitivity (AS). High AS participants with high fear of suffocation rated loads of the same physical intensity as more unpleasant and reported more intense feelings of dyspnea and more respiratory and panic symptoms than low AS individuals. In the second experiment assessing physiological responses to physically comparable loads, high suffocation fear participants showed an increase in minute ventilation to compensate for fear-induced air hunger. This ventilation behavior results in increased frequency of dyspnea sensations, thus increasing fear of suffocation.

  6. Giant Dermoid Cyst Causing Dysphagia and Dyspnea.

    PubMed

    Derin, Serhan; Koseoglu, Sabri; Sahan, Leyla; Dere, Yelda; Sahan, Murat

    2016-05-01

    Dermoid cysts are benign lesions seen in young adults. The second most common localization is the floor of the mouth. They are usually asymptomatic over years but can be symptomatic due to secondary changes or the size. Herein, we report a case of 19-year-old woman who applied to emergency service with dyspnea, dysphagia and enlarging of a mass in the submental region. The patient cannot be entubated because of the mass pushing the tongue base backward closing the laryngeal view. Elective tracheostomy was performed for providing airflow during the operation. After the operation a cystic mass fulfilled with keratin lined by keratinized stratified squamous epithelium in addition to the dermal appendages such as sweat glands and follicular structures were seen histopathologically and the case was diagnosed as dermoid cyst of the submental region. In such patients with quick enlarging of mass causing airway obstructions, the tracheostomy can be the preferable method because of the difficulties in entubation. PMID:26999700

  7. Effects of bronchoconstriction and external resistive loading on the sensation of dyspnea.

    PubMed

    Taguchi, O; Kikuchi, Y; Hida, W; Iwase, N; Satoh, M; Chonan, T; Takishima, T

    1991-12-01

    To determine whether the intensity of dyspnea at a given level of respiratory motor output differs between bronchoconstriction and the presence of an external resistance, we compared the sensation of difficulty in breathing during isocapnic voluntary hyperventilation in six normal subjects. An external resistance of 1.9 cmH2O.1-1.s was applied during both inspiration and expiration. To induce bronchoconstriction, histamine aerosol (5 mg/ml) was inhaled until airway resistance (Raw) increased to a level approximately equal to the subject's control Raw plus the added external resistance. To clarify the role of vagal afferents on the genesis of dyspnea during both forms of obstruction to airflow, the effect of airway anesthesia by lidocaine aerosol inhalation was also examined after histamine and during external resistive loading. The sensation of difficulty in breathing was rated at 30-s intervals on a visual analog scale during isocapnic voluntary hyperpnea, in which the subjects were asked to copy an oscilloscope volume trace obtained previously during progressive hypercapnia. Histamine inhalation significantly increased the intensity of the dyspneic sensation over the equivalent external resistive load at the same levels of ventilation and occlusion pressure during voluntary hyperpnea. Inhaled lidocaine decreased the sensation of dyspnea during bronchoconstriction with no change in Raw, but it did not significantly change the sensation during external resistive loading. These results suggest that afferent vagal activity plays a role in the genesis of dyspnea during bronchoconstriction. PMID:1778911

  8. How to measure dyspnea in acute heart failure?

    PubMed

    Socrates, Thenral; Mebazaa, Alexandre

    2009-09-01

    Dyspnea is the most common presenting symptom of patients with acute heart failure (AHF). Although dyspnea is an important target for treatment in clinical practice and clinical trials, there remains a lack of consensus on how to assess it. We describe and recommend to use absolute scales such the Likert 5-point or the Visual Analogue Scale rather than any comparator scale such as the Likert 7-point scale. We further recommend starting dyspnea measurements in sitting position and perform, if possible, similar measurements in lying position. The same set of measurements may be repeated as needed during the time course of disease and the treatment.

  9. Unexplained dyspnea in a patient of chronic arsenicosis: A diagnostic challenge and learning curve for physicians

    PubMed Central

    Sengupta, Amitabha; Maji, Arnab; Jash, Debraj; Maikap, Malay

    2015-01-01

    Chronic arsenic exposure causes cutaneous effects like hyperkeratosis, peripheral vascular disease, hypertension, ischemic heart disease, non-cirrhotic portal hypertension, hepatomegaly, peripheral neuropathy, respiratory involvement, bad obstetrical outcome, hematological disturbances, and diabetes mellitus. Here we present a case of a 24-year-old lady, with chronic exposure to arsenic, presenting to us with progressive dyspnea. We found pulmonary arterial hypertension (PAH) as a cause of her dyspnea. PAH can occur in arsenicosis, secondary to arsenic-induced chronic obstructive pulmonary disease (COPD), lung fibrosis, and portal hypertension, which we excluded by appropriate investigations in our case. We also excluded a familial or heritable form of PAH. Thus, with the exclusion of all these secondary causes of PAH, as well as a hereditary cause, we came to a conclusion that this PAH might be due to chronic arsenic exposure. To the best of our knowledge, no case of PAH in chronic arsenicosis has been reported to date. PMID:25814805

  10. Does nebulized fentanyl relieve dyspnea during exercise in healthy man?

    PubMed

    Kotrach, Houssam G; Bourbeau, Jean; Jensen, Dennis

    2015-06-01

    Few therapies exist for the relief of dyspnea in restrictive lung disorders. Accumulating evidence suggests that nebulized opioids selective for the mu-receptor subtype may relieve dyspnea by modulating intrapulmonary opioid receptor activity. Our respective primary and secondary objectives were to test the hypothesis that nebulized fentanyl (a mu-opioid receptor agonist) relieves dyspnea during exercise in the presence of abnormal restrictive ventilatory constraints and to identify the physiological mechanisms of this improvement. In a randomized, double-blind, placebo-controlled crossover study, we examined the effect of 250 μg nebulized fentanyl, chest wall strapping (CWS), and their interaction on detailed physiological and perceptual responses to constant work rate cycle exercise (85% of maximum incremental work rate) in 14 healthy, fit young men. By design, CWS decreased vital capacity by ∼20% and mimicked the negative consequences of a mild restrictive lung disorder on exercise endurance time and on dyspnea, breathing pattern, dynamic operating lung volumes, and diaphragmatic electromyographic and respiratory muscle function during exercise. Compared with placebo under both unrestricted control and CWS conditions, nebulized fentanyl had no effect on exercise endurance time, integrated physiological response to exercise, sensory intensity, unpleasantness ratings of exertional dyspnea. Our results do not support a role for intrapulmonary opioids in the neuromodulation of exertional dyspnea in health nor do they provide a physiological rationale for the use of nebulized fentanyl in the management of dyspnea due to mild restrictive lung disorders, specifically those arising from abnormalities of the chest wall and not affiliated with airway inflammation.

  11. Does nebulized fentanyl relieve dyspnea during exercise in healthy man?

    PubMed Central

    Kotrach, Houssam G.; Bourbeau, Jean

    2015-01-01

    Few therapies exist for the relief of dyspnea in restrictive lung disorders. Accumulating evidence suggests that nebulized opioids selective for the mu-receptor subtype may relieve dyspnea by modulating intrapulmonary opioid receptor activity. Our respective primary and secondary objectives were to test the hypothesis that nebulized fentanyl (a mu-opioid receptor agonist) relieves dyspnea during exercise in the presence of abnormal restrictive ventilatory constraints and to identify the physiological mechanisms of this improvement. In a randomized, double-blind, placebo-controlled crossover study, we examined the effect of 250 μg nebulized fentanyl, chest wall strapping (CWS), and their interaction on detailed physiological and perceptual responses to constant work rate cycle exercise (85% of maximum incremental work rate) in 14 healthy, fit young men. By design, CWS decreased vital capacity by ∼20% and mimicked the negative consequences of a mild restrictive lung disorder on exercise endurance time and on dyspnea, breathing pattern, dynamic operating lung volumes, and diaphragmatic electromyographic and respiratory muscle function during exercise. Compared with placebo under both unrestricted control and CWS conditions, nebulized fentanyl had no effect on exercise endurance time, integrated physiological response to exercise, sensory intensity, unpleasantness ratings of exertional dyspnea. Our results do not support a role for intrapulmonary opioids in the neuromodulation of exertional dyspnea in health nor do they provide a physiological rationale for the use of nebulized fentanyl in the management of dyspnea due to mild restrictive lung disorders, specifically those arising from abnormalities of the chest wall and not affiliated with airway inflammation. PMID:26031762

  12. Influence of sustained hypoxia on the sensation of dyspnea.

    PubMed

    Chonan, T; Okabe, S; Hida, W; Satoh, M; Kikuchi, Y; Takishima, T; Shirato, K

    1998-08-01

    We assessed the effect of sustained isocapnic hypoxia (PCO2 = 40 Torr, SaO2 = 80%) on the sensation of dyspnea in 16 normal healthy males. Subjects rated the sensation of dyspnea (c) on 15 cm visual analog scales during 20 min of sustained hypoxia. Following this hypoxic period, 8 subjects undertook mild exercise (10-50 W on a bicycle ergometer for 3 min) under the continuation of hypoxia. During sustained hypoxia, psi increased initially with ventilation from 0.6 +/- 0.2 (n = 16, mean +/- SE) to 2.9 +/- 0.6 at peak ventilation, but it decreased with ventilatory depression to 1.6 +/- 0.4. Dyspnea intensity during hypoxic exercise was significantly smaller than that at peak ventilation in the resting hypoxic period (2.3 +/- 0.7 vs. 3.9 +/- 1.0), although the ventilation was greater during exercise (24.0 +/- 3.0 vs. 19.7 +/- 1.4 l/min). These results indicate that sustained hypoxia has a biphasic, i.e., initial stimulatory and delayed depressant, effect on dyspnea and on ventilation. It is suggested that the dyspnea sensing mechanism is suppressed during mild exercise under sustained hypoxia.

  13. Cardiopulmonary laboratory biomarkers in the evaluation of acute dyspnea

    PubMed Central

    Stokes, Natalie R; Dietz, Brett W; Liang, Jackson J

    2016-01-01

    Dyspnea is a common chief complaint in the emergency department, with over 4 million visits annually in the US. Establishing the correct diagnosis can be challenging, because the subjective sensation of dyspnea can result from a wide array of underlying pathology, including pulmonary, cardiac, neurologic, psychiatric, toxic, and metabolic disorders. Further, the presence of dyspnea is linked with increased mortality in a variety of conditions, and misdiagnosis of the cause of dyspnea leads to poor patient-level outcomes. In combination with the history and physical, efficient, and focused use of laboratory studies, the various cardiopulmonary biomarkers can be useful in establishing the correct diagnosis and guiding treatment decisions in a timely manner. Use and interpretation of such tests must be guided by the clinical context, as well as an understanding of the current evidence supporting their use. This review discusses current standards and research regarding the use of established and emerging cardiopulmonary laboratory markers in the evaluation of acute dyspnea, focusing on recent evidence assessing the diagnostic and prognostic utility of various tests. These markers include brain natriuretic peptide (BNP) and N-terminal prohormone (NT-proBNP), mid-regional peptides proatrial NP and proadrenomedullin, cardiac troponins, D-dimer, soluble ST2, and galectin 3, and included is a discussion on the use of arterial and venous blood gases. PMID:27307771

  14. Experimental Contact Lens to Prevent Glaucoma-Induced Blindness

    MedlinePlus

    ... Articles | Inside Life Science Home Page An Experimental Contact Lens to Prevent Glaucoma-Induced Blindness By Sharon Reynolds Posted January 23, 2014 An experimental contact lens design releases a glaucoma medicine at a ...

  15. [Experimental and human nephrotoxicity induced by ochratoxins].

    PubMed

    Fillastre, J P

    1997-10-01

    Ochratoxin A is a mycotoxin: a dihydroisocoumarin derivative linked to L. beta phenylalanine. Ochratoxin A is produced by a number of Aspergillus and Penicillium species. This mycotoxin is a carcinogenic, teratogenic, mutagenic and immunosuppressive substance. Ochratoxin A is a common contaminant found in a variety of foods for human nutrition as well as animal feeds. The aim of this study is to discuss nephrotoxic properties of this mycotoxin in humans. Nephrotoxicity has been reported in many animals after exposure to ochratoxin A. Porcine nephropathy due to this mycotoxin is a well known disease characterized by impairment of proximal renal function. Renal damage is also confined to the proximal tubule in other animal species. A good correlation is found between renal function abnormalities and the location of the lesions along the nephron. Of particular interest is the presence of nuclear abnormalities of the epithelial cells with pyknosis, karyorrhexis and karyomegaly. The question is to know if ochratoxin is nephrotoxic in humans. Acute nephrotoxicity seems to be very rare and we found only one case report suggesting such a possibility. We observed the occurrence of chronic renal failure in two patients with a possible responsibility of a chronic ochratoxin A intoxication. Clinical and histologic findings in these two patients were quite similar to those described in several cases of karyomegalic interstitial nephritis. Striking similarities between the changes in renal structure and function seen in ochratoxin A-induced experimental nephropathies and in Balkan endemic nephropathy suggest a common etiologic agent. This mycotoxin could be also responsible for interstitial nephropathies in North Africa.

  16. Dyspnea in acute bronchial asthma in an emergency room.

    PubMed

    Kunitoh, H; Watanabe, K; Sajima, Y

    1994-03-01

    Pulmonary function, arterial blood gases, and pulse rate were prospectively compared with dyspnea perceived by patients before and after emergency room treatment for acute asthma in 83 episodes. Subjective degree of dyspnea was rated on a modified Borg scale. Before treatment, all spirometry (FVC, FEV1, and peak expiratory flow rate) and arterial blood gas (PaO2, PaCO2, and bicarbonate) data as well as pulse rate were significantly correlated with modified Borg scale, but only PaCO2 showed significant correlation (P < .001) in a multivariate analysis. After treatment, only PaO2 was significantly correlated with modified Borg scale (P = .008) in a multivariate analysis, and pulse rate showed correlation of borderline significance (P = .06). In another 37 episodes of relapsed acute asthma, the correlations between laboratory data and modified Borg scale were very weak, especially after treatment. We conclude that dyspnea expressed by asthmatic patients in an emergency room might be reflecting different mechanisms as treatment is performed. Although it should be one useful guide in emergency evaluation, it must be recognized that dyspnea in the same patient could mean different abnormalities.

  17. Effects of expiratory resistive loading on the sensation of dyspnea.

    PubMed

    Chonan, T; Altose, M D; Cherniack, N S

    1990-07-01

    To determine whether an increase in expiratory motor output accentuates the sensation of dyspnea (difficulty in breathing), the following experiments were undertaken. Ten normal subjects, in a series of 2-min trials, breathed freely (level I) or maintained a target tidal volume equal to (level II) or twice the control (level III) at a breathing frequency of 15/min (similar to the control frequency) with an inspiratory load, an expiratory load, and without loads under hyperoxic normocapnia. In tests at levels II and III, end-expiratory lung volume was maintained at functional residual capacity. A linear resistance of 25 cmH2O.1(-1).s was used for both inspiratory and expiratory loading; peak mouth pressure (Pm) was measured, and the intensity of dyspnea (psi) was assessed with a visual analog scale. The sensation of dyspnea increased significantly with the magnitude of expiratory Pm during expiratory loading (level II: Pm = 9.4 +/- 1.5 (SE) cmH2O, psi = 1.26 +/- 0.35; level III: Pm = 20.3 +/- 2.8 cmH2O, psi = 2.22 +/- 0.48) and with inspiratory Pm during inspiratory loading (level II: Pm = 9.7 +/- 1.2 cmH2O, psi = 1.35 +/- 0.38; level III: Pm = 23.9 +/- 3.0 cmH2O, psi = 2.69 +/- 0.60). However, at each level of breathing, neither the intensity of dyspnea nor the magnitude of peak Pm during loading was different between inspiratory and expiratory loading. The augmentation of dyspnea during expiratory loading was not explained simply by increases in inspiratory activity. The results indicate that heightened expiratory as well as inspiratory motor output causes comparable increases in the sensation of difficulty in breathing.

  18. "Experimental amnesia" induced by emotional items.

    PubMed

    Angelini, R; Capozzoli, F; Lepore, P; Grossi, D; Orsini, A

    1994-02-01

    Tulving described an effect of retrograde amnesia in a free-recall task of word lists, produced by inserting items having priority in recall. Other authors confirmed the amnesic effect without giving instructions for priority both in recall and in recognition tasks. The effect was explained by Tulving as a premature termination of encoding processes. The similarity between these experiments and the researches aimed at reproducing amnesia by emotional trauma led us to hypothesize that the two phenomena might be due to the same functional mechanisms. We have organized a free-recall task of word lists into which emotional items were inserted. Our aim was to verify whether with these experimental conditions Tulving's results would be reproduced. The obtained data show amnesic effects in free recall; nevertheless, they do not seem to confirm closely the experimental hypothesis. Lastly, changes in primacy and recency effects produced by emotional items are analyzed.

  19. Polymorphonuclear leukocyte kinetics in experimentally induced keratitis.

    PubMed

    Chusid, M J; Davis, S D

    1985-02-01

    The movement of polymorphonuclear leukocytes (PMNLs) into inflamed corneas was studied using a quantitative technique to measure PMNL chemotaxis in vivo. Our studies suggested that, in this model, most PMNLs enter the cornea through limbal vessels. A variety of bacterial agents, including viable bacteria, killed bacteria, culture filtrates, and endotoxin, were found to induce a significant corneal inflammatory response. Of the agents tested, viable Pseudomonas aeruginosa produced greatest inflammation. Host factors (serum, PMNLs) also induced movement of PMNLs into corneas, but only after preincubation with activating agents. Normal serum, resting PMNLs, and PMNL lysates derived from resting cells did not promote PMNL corneal ingress. These studies provide further insight into the movement of PMNLs into the inflamed cornea and information that may be of use in developing techniques to inhibit the corneal inflammatory response. PMID:3977698

  20. Imaging-based assessment of dyspnea in cigarette smokers

    NASA Astrophysics Data System (ADS)

    Galvin, Jeffrey R.; Chang, Paul J.; Schwartz, David A.; Hunninghake, Gary W.; Helmers, Richard; Mori, Masaki

    1994-05-01

    Patients with pulmonary fibrosis frequently smoke cigarettes. The cause of dyspnea in these patients is often complex because of the coexistence of multiple disease processes. We investigated 10 cigarette smokers with pulmonary fibrosis who were referred for evaluation of new onset or worsening dyspnea. Chest radiographs and pulmonary function tests were obtained in addition to high-resolution computed tomography (HRCT). In those patients with HRCT evidence of both diseases, spirometry and lung volumes were most often normal. Although plain films provided a reasonable assessment of fibrosis, they underestimated the severity of emphysema. Quantitation of both emphysema and fibrosis by HRCT was reproducible and correlated with key pulmonary function tests. Our findings indicate that the HRCT scan is a useful diagnostic test in patients with pulmonary fibrosis who are also cigarette smokers.

  1. Acute dyspnea and a new murmur in a team physician.

    PubMed

    Cantwell, J D; Watson, D T; Blincoe, W A; Kauten, J R

    1998-05-01

    A 61-year-old physician for a professional sports team experienced transient palpitations and dyspnea while playing in an over-50 basketball scrimmage. He had been physically active for many years, had no known cardiopulmonary disorders, and had never been told of a heart murmur. He had not been febrile, nor had he experienced any chest pain. There was no history of recent dental work.

  2. Experimental and analytical investigation of flow through rocket pump inducer

    NASA Technical Reports Server (NTRS)

    Lakshminarayana, B.

    1974-01-01

    The characteristics of a rocket pump inducer are discussed. The effect of the pumping requirements on the blade configuration is analyzed. The effects of viscosity on blade design were determined by tests of a four bladed inducer operated in air at a flow coefficient of 0.065. The fluid properties were measured at the exit of the inducer using conventional and hot wire probes. The experimental results and the method of predicting the outlet tangential velocity and head rise are discussed.

  3. Prevalence and Predictive Value of Dyspnea Ratings in Hospitalized Patients: Pilot Studies

    PubMed Central

    Stevens, Jennifer P.

    2016-01-01

    Background Dyspnea (breathing discomfort) can be as powerfully aversive as pain, yet is not routinely assessed and documented in the clinical environment. Routine identification and documentation of dyspnea is the first step to improved symptom management and it may also identify patients at risk of negative clinical outcomes. Objective To estimate the prevalence of dyspnea and of dyspnea-associated risk among hospitalized patients. Design Two pilot prospective cohort studies. Setting Single academic medical center. Patients Consecutive patients admitted to four inpatient units: cardiology, hematology/oncology, medicine, and bariatric surgery. Measurements In Study 1, nurses documented current and recent patient-reported dyspnea at the time of the Initial Patient Assessment in 581 inpatients. In Study 2, nurses documented current dyspnea at least once every nursing shift in 367 patients. We describe the prevalence of burdensome dyspnea, and compare it to pain. We also compared dyspnea ratings with a composite of adverse outcomes: 1) receipt of care from the hospital’s rapid response system, 2) transfer to the intensive care unit, or 3) death in hospital. We defined burdensome dyspnea as a rating of 4 or more on a 10-point scale. Results Prevalence of burdensome current dyspnea upon admission (Study 1) was 13% (77 of 581, 95% CI 11%-16%). Prevalence of burdensome dyspnea at some time during the hospitalization (Study 2) was 16% (57 of 367, 95% CI 12%-20%). Dyspnea was associated with higher odds of a negative outcome. Conclusions In two pilot studies, we identified a significant symptom burden of dyspnea in hospitalized patients. Patients reporting dyspnea may benefit from a more careful focus on symptom management and may represent a population at greater risk for negative outcomes. PMID:27070144

  4. A Giant Ovarian Tumor Causing Anasarca and Dyspnea Successfully Managed after Preoperative Drainage.

    PubMed

    Yamaguchi, Munekage; Tashiro, Hironori; Takaishi, Kiyomi; Honda, Ritsuo; Katabuchi, Hidetaka

    2015-01-01

    Serious complications are likely to accompany the treatment of giant ovarian tumors, and resection with or without preoperative drainage has been previously reported. Here, we report the case of a 27-year-old Japanese woman with a significant weight gain of 50 kg, who was referred to the Kumamoto University Hospital because of gait impairment and dyspnea. Imaging tests revealed an ovarian tumor, 37 cm in diameter, with two solid components. The patient's condition improved after the removal of 31.5 l tumor fluid by using a suprapubic urinary catheter for 3 days. The tumor was subsequently resected without complications, and was diagnosed as a left mucinous ovarian tumor with malignant components, weighing 37 kg (81.5 lb). The patient was discharged after her anasarca improved, and her body weight decreased from 100 to 50 kg with accompanying considerable urination within two weeks. She was in good condition with no evidence of recurrence at 15 months after surgery. Tumor resection after preoperative drainage was effective in the management of a patient with dyspnea induced by a giant ovarian tumor. We suggest the use of a suprapubic urinary catheter for preoperative drainage because of its ease of use in preventing fluid leakage from the possibly malignant tumor. PMID:25661539

  5. Experimental background due to particle induced gas desorption in RHIC

    SciTech Connect

    Zhang,S.Y.; Trbojevic, D.

    2008-08-10

    Beam-gas collision created experimental background, i.e., singles, has affected heavy ion and polarized proton operations in Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The gas molecules in interaction region are mainly caused by the electron induced gas desorption. and the electrons are produced from the beam induced electron multipacting, or called electron cloud. The background has a dependence on the usual electron cloud related parameters, such as the bunch intensity, bunch spacing, and the solenoid field. With the RHIC upgrade plan, the experimental background may become a luminosity limiting factor. Mitigations are discussed.

  6. Experimentally induced otitis and audiogenic seizure in the mouse.

    PubMed

    Niaussat, M M

    1977-04-15

    Audiogenic seizures can be induced in genetically non-susceptible 17-day-old mice (Rb/3 strain) with various results. Priming only induces 9% of seizures, auditory insulation 3,8%, while experimental otitis leads to 79%. The hypothesis concerning disuse supersensitivity subsequent to acoustic deprivation was not confirmed by the experiment. However, modification of acoustic transmission at middle ear level induced by otitis or ear physical damage during the maturation period, exposes the upper nervous centers to intense stimulation to which the reaction is a recruiting response. PMID:862735

  7. Experimentally Induced Learned Helplessness: How Far Does it Generalize?

    ERIC Educational Resources Information Center

    Tuffin, Keith; And Others

    1985-01-01

    Assessed whether experimentally induced learned helplessness on a cognitive training task generalized to a situationally dissimilar social interaction test task. No significant differences were observed between groups on the subsequent test task, showing that helplessness failed to generalize. (Author/ABB)

  8. Parapharyngeal space lipomatosis with secondary dyspnea, disphagia and disphonia

    PubMed Central

    Garcia-Ortega, Dorian Yarih; Gomez-Pedraza, Antonio; Luna-Ortiz, Kuauhyama

    2015-01-01

    Introduction Parapharyngeal space tumors are a small percentage of all head and neck neoplasms. Due to their anatomic location, they represent a therapeutic challenge. To our knowledge, 11 cases of parapharyngeal lipomatous tumors have been reported in the literature. Case A 48 year old male with chief complaints of dyspnea, dysphagia and dysphonia was found to have a parapharyngeal space tumor. He was scheduled to undergo lumpectomy and neck exploration. Discussion Benign tumors represented 70% of all cases. Open neck surgery is considered the gold-standard of treatment. Conclusion It is important to bear in mind the lipomas of the parapharyngeal space to establish an accurate diagnosis and implement timely, appropriate treatment in order to avoid future complications and reduce morbidity and mortality. PMID:26318127

  9. Impact of pulmonary rehabilitation on the major dimensions of dyspnea in COPD.

    PubMed

    Wadell, Karin; Webb, Katherine A; Preston, Megan E; Amornputtisathaporn, Naparat; Samis, Lorelei; Patelli, Jennifer; Guenette, Jordan A; O'Donnell, Denis E

    2013-08-01

    The evaluation of dyspnea and its responsiveness to therapy in COPD should consider the multidimensional nature of this symptom in each of its sensory-perceptual (intensity, quality), affective and impact domains. To gain new insights into mechanisms of dyspnea relief following pulmonary rehabilitation (PR), we examined effects on the major domains of dyspnea and their interaction with physiological training effects. This randomized, controlled study was conducted in 48 subjects with COPD. Subjects received either 8-weeks of PR or usual care (CTRL). Pre- and post-intervention assessments included: sensory-perceptual (i.e., exertional dyspnea intensity, dyspnea descriptors at end-exercise), affective (i.e., intensity of breathing-related anxiety during exercise, COPD self-efficacy, walking self-efficacy) and impact (i.e., activity-related dyspnea measured by the Baseline/Transition Dyspnea Index, Chronic Respiratory Questionnaire dyspnea component, St. George's Respiratory Disease Questionnaire activity component) domains of dyspnea; functional performance (i.e., 6-minute walk, endurance shuttle walk); pulmonary function; and physiological measurements during constant work rate cycle exercise at 75% of the peak incremental work rate. Forty-one subjects completed the study: PR (n = 17) and CTRL (n = 24) groups were well matched for age, sex, body size and pulmonary function. There were no significant between-group differences in pre- to post-intervention changes in pulmonary function or physiological parameters during exercise. After PR versus CTRL, significant improvements were found in the affective and impact domains but not in the sensory-perceptual domain of dyspnea. In conclusion, clinically meaningful improvements in the affective and impact domains of dyspnea occurred in response to PR in the absence of consistent physiological training effects. PMID:23537344

  10. The assessment of dyspnea during the vigorous intensity exercise by three Dyspnea Rating Scales in inactive medical personnel.

    PubMed

    Intarakamhang, Patrawut; Wangjongmeechaikul, Piyathida

    2013-07-24

    It is well recognized that exercise is good for health especially as it's known to prevent metabolic syndromes such as diabetes, hypertension and heart disease. To reap the benefits from exercise the most appropriate level of intensity must be determined, the level of intensity ranging from low, low to moderate to hard (vigorous). This study is aimed to 1. To investigate and evaluate 3 subjective rating scales. The Borg scale, the Combined Numerical Rating Scale (NRS) + FACES Dyspnea Rating Scale (FACES) and the Likert scale, during hard (vigorous) exercise. 2. To compare the effectiveness of the Borg scale and Combined Numerical Rating Scale (NRS) + FACES Dyspnea Rating Scale during the hard (vigorous) intensity exercise. This study uses a descriptive methodology. The sample group was 73 medical personnel that were leading an inactive life style, volunteers from Phramongkutklao Hospital. Participants were randomly divided into 3 groups. Group 1, those to report using the Borg Scale, group 2 using NRS + FACES, and group 3 to subjectively assess the intensity of the exercise using the Likert scale during a treadmill Exercise Stress Test (EST) using the Bruce protocol. The upper limit of the intensity in the study was equal to 85% of the maximal heart rate of all participants. The subjective reporting of the experienced level of dyspnea was undertaken immediately after the completion of exercise. The average age of participants was 23.37 years old. The 26 participants reporting using the Borg scale had mean Borg scale score of 13.46+1.77, a mode score of 15. The 24 participants reporting intensity levels through NRS +FACES had a mean NRS + FACES score of 6.83+1.09 and mode on the NRS + FACES scale equal to 7. The Likert scale group evaluated 23 participants with a mean Likert scale score of 2.74. That is those choosing Levels 2 and 3 were 6 (26.9%) and 17 participants (73.95%), respectively. Comparing the two groups with the Borg scale at equal to or greater than 15

  11. [Functional capacity (dyspnea) and quality of life in patients with chronic obstructive lung disease (COPD): instruments of assessment and methodological aspects].

    PubMed

    Hütter, B O; Würtemberger, G

    1999-03-01

    disease-specific instruments are supposed to be more sensitive to small therapeutically induced changes. However, the empirical results in patients with COPD are mixed and do not clearly favour disease-specific instruments. Lung function, dyspnea measures and exercise tolerance as well do not correlate strongly with HRQOL. Most associations cover only between 10% and 16% of shared variance. Exercise tolerance is not well associated with lung function but correlates better with HRQOL. Nowadays we can rely on several measures for dyspnea and HRQOL which have been thoroughly verified methodologically in COPD patients. However, some disease-specific and generic instruments exhibit substantial flaws, so that they need to be revised and it seems better not to use them at present. Many methodological and conceptual questions remain unanswered in the field indicating a strong need for more research. PMID:10226475

  12. PHARMACOLOGIC TREATMENT OF HYPERALGESIA EXPERIMENTALLY INDUCED BY NUCLEUS PULPOSUS

    PubMed Central

    de Souza Grava, André Luiz; Ferrari, Luiz Fernando; Parada, Carlos Amílcar; Defino, Helton Luiz Aparecido

    2015-01-01

    Objective: To evaluate the effect of anti-inflammatory drugs (dexamethasone, indomethacin, atenolol and indomethacin plus atenolol) and analgesic drugs (morphine) on hyperalgesia experimentally induced by the nucleus pulposus (NP) in contact with the L5 dorsal root ganglion (DRG). Methods: Thirty male Wistar rats of weights ranging from 220 to 250 g were used in the study. Hyperalgesia was induced by means of a fragment of NP removed from the sacrococcygeal region that was placed in contact with the L5 dorsal root ganglion. The 30 animals were divided into experimental groups according to the drug used. The drugs were administered for two weeks after the surgical procedure to induce hyperalgesia. Mechanical and thermal hyperalgesia was evaluated using the paw pressure test, von Frey electronic test and Hargreaves test, over a seven-week period. Results: The greatest reduction of hyperalgesia was observed in the group of animals treated with morphine, followed by dexamethasone, indomethacin and atenolol. Reductions in hyperalgesia were observed after drug administration ceased, except for the group of animals treated with morphine, in which there was an increase in hyperalgesia after discontinuation of the treatment. Conclusion: Hyperalgesia induced by NP contact with the DRG can be reduced through administration of anti-inflammatory and analgesic drugs, but a greater reduction was observed with the administration of dexamethasone. PMID:27026966

  13. [Clinical significance of natriuretic peptides in the differential diagnosis of dyspnea].

    PubMed

    Špác, Jiří

    2016-01-01

    Acute dyspnea is one of the most common emergency department symptoms. But early diagnosis and treatment could be e challenging because of multiple potential causes. The gold standard biomarkers in cardiac dyspnea are B-type natriuretic peptide (BNP) and N-terminal pro-B-type (natriuretic peptide NT-pro BNP), which play an important role in the diagnosis, prognosis, and management of acute decompensated heart failure. The purpose of this review is to analyze diagnostic potential of BNP and NT-pro BNP biomarkers use in patients with acute dyspnea. BNP and NT-proBNP are markers of cardiac stress but are not cardiac-specific. They have comparable clinical utility, and both help in excluding acute cardiac dyspnea but they cannot reliably discriminate systolic from diastolic HF.Key word: acute dyspnea - natriuretic peptide - heart failure. PMID:27627091

  14. Elastase-induced pulmonary emphysema: insights from experimental models.

    PubMed

    Antunes, Mariana A; Rocco, Patricia R M

    2011-12-01

    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. PMID:22159348

  15. Elastase-induced pulmonary emphysema: insights from experimental models.

    PubMed

    Antunes, Mariana A; Rocco, Patricia R M

    2011-12-01

    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.

  16. Dyspnea in a nonagenarian: The usual suspects, an unexpected culprit.

    PubMed

    Madeira, Sérgio; Raposo, Luís; David, Raquel; Marques, Alexandre; Andrade Gomes, José; Cardim, Nuno; Anjos, Rui

    2015-09-01

    Platypnea-orthodeoxia syndrome (POS) is an uncommon syndrome characterized by dyspnea and hypoxemia triggered by orthostatism and relieved by recumbency. It is often associated with an interatrial shunt through a patent foramen ovale (PFO). We report the case of a 92-year-old woman initially admitted in the setting of a traumatic femoral neck fracture (successfully treated with hip replacement surgery) in whom a reversible decline in transcutaneous oxygen saturation from 98% (in the supine position) to 84% (in the upright position) was noted early post-operatively. Thoracic multislice computed tomography excluded pulmonary embolism and severe parenchymal lung disease. The diagnosis of POS was confirmed by tilt-table contrast transesophageal echocardiography, which demonstrated a dynamic and position-dependent right-to-left shunt (torrential when semi-upright and minimal in the supine position) through a PFO. The patient underwent percutaneous closure of the PFO with an Amplatzer device, which led to prompt symptom relief and full functional recovery. PMID:26320092

  17. Dyspnea in a nonagenarian: The usual suspects, an unexpected culprit.

    PubMed

    Madeira, Sérgio; Raposo, Luís; David, Raquel; Marques, Alexandre; Andrade Gomes, José; Cardim, Nuno; Anjos, Rui

    2015-09-01

    Platypnea-orthodeoxia syndrome (POS) is an uncommon syndrome characterized by dyspnea and hypoxemia triggered by orthostatism and relieved by recumbency. It is often associated with an interatrial shunt through a patent foramen ovale (PFO). We report the case of a 92-year-old woman initially admitted in the setting of a traumatic femoral neck fracture (successfully treated with hip replacement surgery) in whom a reversible decline in transcutaneous oxygen saturation from 98% (in the supine position) to 84% (in the upright position) was noted early post-operatively. Thoracic multislice computed tomography excluded pulmonary embolism and severe parenchymal lung disease. The diagnosis of POS was confirmed by tilt-table contrast transesophageal echocardiography, which demonstrated a dynamic and position-dependent right-to-left shunt (torrential when semi-upright and minimal in the supine position) through a PFO. The patient underwent percutaneous closure of the PFO with an Amplatzer device, which led to prompt symptom relief and full functional recovery.

  18. Corticostriatal Plastic Changes in Experimental L-DOPA-Induced Dyskinesia

    PubMed Central

    Ghiglieri, Veronica; Bagetta, Vincenza; Pendolino, Valentina; Picconi, Barbara; Calabresi, Paolo

    2012-01-01

    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. PMID:22666628

  19. Experimental realization of optomechanically induced non-reciprocity

    NASA Astrophysics Data System (ADS)

    Shen, Zhen; Zhang, Yan-Lei; Chen, Yuan; Zou, Chang-Ling; Xiao, Yun-Feng; Zou, Xu-Bo; Sun, Fang-Wen; Guo, Guang-Can; Dong, Chun-Hua

    2016-10-01

    Non-reciprocal devices, such as circulators and isolators, are indispensable components in classical and quantum information processing in integrated photonic circuits. Aside from these applications, the non-reciprocal phase shift is of fundamental interest for exploring exotic topological photonics, such as the realization of chiral edge states and topological protection. However, incorporating low-optical-loss magnetic materials into a photonic chip is technically challenging. In this study we experimentally demonstrate non-magnetic non-reciprocity using optomechanical interactions in a whispering gallery microresonator, as proposed in a previous work. Optomechanically induced non-reciprocal transparency and amplification are observed and a non-reciprocal phase shift of up to 40° is also demonstrated. The underlying mechanism of optomechanically induced non-reciprocity has great potential for all-optical controllable isolators and circulators, as well as non-reciprocal phase shifters in integrated photonic chips.

  20. Individual differences in susceptibility to experimentally induced phantom sensations.

    PubMed

    Burrack, Anna; Brugger, Peter

    2005-09-01

    We investigated individual differences in susceptibility to two vibration-induced phantom illusions, i.e. illusory arm extension and nose prolongation ("Pinocchio illusion"). Vibration was applied to the biceps brachii tendon of 32 healthy participants. Susceptibility to the illusions was quantified by vividness ratings and by ratings of the amount of illusory position changes of the arm and illusory shape changes of the nose. Participants also completed the Perceptual Aberration (PA) and the Need for Cognition (NFC) inventories. PA reflects the frequency of spontaneously experienced body schema alterations and NFC a person's tendency to cognitively structure experiences. PA was positively correlated with participants' susceptibility to illusory arm extension and, exclusively for men, also to nose elongation. A high NFC was weakly associated with a high susceptibility for the Pinocchio illusion. By inference, these findings indicate a physiological basis of PA and a cognitive mediation of experimentally induced phantom sensations.

  1. Ichnocarpus frutescens Ameliorates Experimentally Induced Convulsion in Rats

    PubMed Central

    Singh, Narendra Kumar; Laloo, Damiki; Garabadu, Debapriya; Singh, Tryambak Deo; Singh, Virendra Pratap

    2014-01-01

    The present study was carried out to evaluate the anticonvulsant activity and probable mechanism of action of the methanol root extract from I. frutescens (MEIF) using different experimental animal models. Anticonvulsant activity of the single dose of MEIF (100, 200, and 400 mg/kg, p.o.) was evaluated in maximal electroshock- (MES-), pentylenetetrazole- (PTZ-), and isoniazid- (INH-) induced convulsions models in rats. The levels of γ-amino butyric acid (GABA), glutamate, GABA-transaminase (GABA-T) activity and oxidative stress markers were measured in pretreated rat's brain homogenate to corroborate the mechanism of observed anticonvulsant activity. MEIF (200–400 mg/kg, p.o.) protected the animals in all the behavioral models used. Pretreatment of MEIF (200–400 mg/kg, p.o.) and diazepam (1.0 mg/kg, i.p.) to the animals in INH-induced convulsion model showed 100% and 80% protection, respectively, as well as significant restoration of GABA and glutamate level in the rat's brain. MEIF and vigabatrin (50 mg/kg, i.p.) reduced the PTZ-induced increase in the activity of GABA-T (46%) in the brain. Further, MEIF reversed the PTZ-induced increase in lipid peroxidase (LPO) and decrease in reduced glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) activities. The findings of this study validate the anticonvulsant activity of I. frutescens. PMID:27379268

  2. Pathogenesis of experimentally induced feline immunodeficiency virus infection in cats.

    PubMed

    Yamamoto, J K; Sparger, E; Ho, E W; Andersen, P R; O'Connor, T P; Mandell, C P; Lowenstine, L; Munn, R; Pedersen, N C

    1988-08-01

    Feline immunodeficiency virus (FIV; formerly, feline T-lymphotropic lentivirus) is a typical lentivirus resembling human and simian immunodeficiency viruses in morphologic features, protein structure, and reverse transcriptase enzyme. It is antigenically dissimilar, however. The virus is tropic for primary and permanent feline T-lymphoblastoid cells and Crandell feline kidney cells. The virus did not grow in other permanent feline non-lymphoblastoid cells that were tested, or in lymphoid and non-lymphoid cells from man, dogs, mice, and sheep. During short-term inoculation studies in cats, the feline immunodeficiency-like syndrome found in nature was not experimentally induced, but a distinct primary phase of infection was observed. Fever and neutropenia were observed 4 to 5 weeks after inoculation; fever lasted several days, and neutropenia persisted from 1 to 9 weeks. Generalized lymphadenopathy that persisted for 2 to 9 months appeared at the same time. Antibodies to FIV appeared 2 weeks after inoculation and then plateaued. Virus was reisolated from the blood of all infected cats within 4 to 5 weeks after inoculation and persisted indefinitely in the face of humoral antibody response. Virus was recovered from blood, plasma, CSF and saliva, but not from colostrum or milk. Contact transmission was achieved slowly in one colony of naturally infected cats, but not between experimentally infected and susceptible specific-pathogen-free cats kept together for periods as long as 4 to 14 months. The infection was transmitted readily, however, by parenteral inoculation with blood, plasma, or infective cell culture fluids. In utero and lactogenic transmission were not observed in kittens born to naturally or experimentally infected queens. Lymphadenopathy observed during the initial stage of FIV infection was ascribed to lymphoid hyperplasia and follicular dysplasia. A myeloproliferative disorder was observed in 1 cat with experimentally induced infection. PMID:2459996

  3. An official American Thoracic Society workshop report: assessment and palliative management of dyspnea crisis.

    PubMed

    Mularski, Richard A; Reinke, Lynn F; Carrieri-Kohlman, Virginia; Fischer, Mark D; Campbell, Margaret L; Rocker, Graeme; Schneidman, Ann; Jacobs, Susan S; Arnold, Robert; Benditt, Joshua O; Booth, Sara; Byock, Ira; Chan, Garrett K; Curtis, J Randall; Donesky, Doranne; Hansen-Flaschen, John; Heffner, John; Klein, Russell; Limberg, Trina M; Manning, Harold L; Morrison, R Sean; Ries, Andrew L; Schmidt, Gregory A; Selecky, Paul A; Truog, Robert D; Wang, Angela C C; White, Douglas B

    2013-10-01

    In 2009, the American Thoracic Society (ATS) funded an assembly project, Palliative Management of Dyspnea Crisis, to focus on identification, management, and optimal resource utilization for effective palliation of acute episodes of dyspnea. We conducted a comprehensive search of the medical literature and evaluated available evidence from systematic evidence-based reviews (SEBRs) using a modified AMSTAR approach and then summarized the palliative management knowledge base for participants to use in discourse at a 2009 ATS workshop. We used an informal consensus process to develop a working definition of this novel entity and established an Ad Hoc Committee on Palliative Management of Dyspnea Crisis to further develop an official ATS document on the topic. The Ad Hoc Committee members defined dyspnea crisis as "sustained and severe resting breathing discomfort that occurs in patients with advanced, often life-limiting illness and overwhelms the patient and caregivers' ability to achieve symptom relief." Dyspnea crisis can occur suddenly and is characteristically without a reversible etiology. The workshop participants focused on dyspnea crisis management for patients in whom the goals of care are focused on palliation and for whom endotracheal intubation and mechanical ventilation are not consistent with articulated preferences. However, approaches to dyspnea crisis may also be appropriate for patients electing life-sustaining treatment. The Ad Hoc Committee developed a Workshop Report concerning assessment of dyspnea crisis; ethical and professional considerations; efficient utilization, communication, and care coordination; clinical management of dyspnea crisis; development of patient education and provider aid products; and enhancing implementation with audit and quality improvement.

  4. Repeatability of the Evaluation of Perception of Dyspnea in Normal Subjects Assessed Through Inspiratory Resistive Loads

    PubMed Central

    Fernandes, Andréia K; Ziegler, Bruna; Konzen, Glauco L; Sanches, Paulo R.S; Müller, André F; Pereira, Rosemary P; Dalcin, Paulo de Tarso R

    2014-01-01

    Purpose: Study the repeatability of the evaluation of the perception of dyspnea using an inspiratory resistive loading system in healthy subjects. Methods: We designed a cross sectional study conducted in individuals aged 18 years and older. Perception of dyspnea was assessed using an inspiratory resistive load system. Dyspnea was assessed during ventilation at rest and at increasing resistive loads (0.6, 6.7, 15, 25, 46.7, 67, 78 and returning to 0.6 cm H2O/L/s). After breathing in at each level of resistive load for two minutes, the subject rated the dyspnea using the Borg scale. Subjects were tested twice (intervals from 2 to 7 days). Results: Testing included 16 Caucasian individuals (8 male and 8 female, mean age: 36 years). The median scores for dyspnea rating in the first test were 0 at resting ventilation and 0, 2, 3, 4, 5, 7, 7 and 1 point, respectively, with increasing loads. The median scores in the second test were 0 at resting and 0, 0, 2, 2, 3, 4, 4 and 0.5 points, respectively. The intra-class correlation coefficient was 0.57, 0.80, 0.74, 0.80, 0.83, 0.86, 0.91, and 0.92 for each resistive load, respectively. In a generalized linear model analysis, there was a statistically significant difference between the levels of resistive loads (p<0.001) and between tests (p=0.003). Dyspnea scores were significantly lower in the second test. Conclusion: The agreement between the two tests of the perception of dyspnea was only moderate and dyspnea scores were lower in the second test. These findings suggest a learning effect or an effect that could be at least partly attributed to desensitization of dyspnea sensation in the brain. PMID:25614771

  5. Cardiac or pulmonary dyspnea in patients admitted to the emergency department.

    PubMed

    Malas, O; Cağlayan, B; Fidan, A; Ocal, Z; Ozdoğan, S; Torun, E

    2003-12-01

    A simple and quick way of discrimination between cardiac and pulmonary causes of dyspnea is essential in patients admitted to the emergency department. We aimed to assess the utility of easily applicable diagnostic tools in the differential diagnosis of cardiac and pulmonary causes of dyspnea in patients presenting with shortness of breath. Clinical and radiologic evaluation, peak expiratory flow (PEF), PaO2, PaCO2 measurements were performed in 94 patients admitted to the emergency room with dyspnea. All the patients were hospitalized for accurate diagnosis and later were categorized into cardiac and pulmonary dyspnea groups. PEF, %PEF (percent of predicted PEF), dyspnea differentiation index (DDI = PEF x PaO2/1000), %DDI (%PEF x PaO2/1000), PaO2 and PaCO2 measurements were compared between the two groups. When cardiac and pulmonary dyspnea groups were compared, considering 1.6 as the cut-off value for DDI, measurements above this value imply cardiac pathology with 76.7% sensitivity and 67.2% specificity. The sensitivity and specificity for cardiac dyspnea calculated according to the cut-off values were 96.7% and 40.6% for %DDI; 86.7% and 60.9% for PEF; 86.7% and 54.7% for %PEF; 66.7 and 68.7 for PaO2. Also for pulmonary dyspnea, sensitivity and specificity values for PaCO2 were 50% and 93%. We conclude that DDI, %DDI, PEF, %PEF, PaO2 and PaCO2 are simple and easily applicable tools for differential diagnosis of cardiac and pulmonary dyspnea. Adjunctive utility of these tests in the emergency department with clinical and radiologic evaluation contributes to this discrimination.

  6. Treating Dyspnea: Is Oxygen Therapy the Best Option for All Patients?

    PubMed

    Baldwin, Jennifer; Cox, Jaclyn

    2016-09-01

    The high prevalence of dyspnea at the end of life carries with it significant health and economic burden. Given the complex mechanism of dyspnea, management should be tailored to the individual patient experience and the underlying disease process. No clear role for supplemental oxygen has been established in the treatment of dyspnea in patients without no hypoxemia, and providers should consider the negative effects of oxygen supplementation. Symptom control with medications, exercise, behavioral therapy, treatment of associated anxiety, and the use of fans may be more effective and less costly than oxygen therapy. Further research is needed in the assessment and treatment of this symptom to more effectively treat patients. PMID:27542431

  7. Silibinin ameliorates LPS-induced memory deficits in experimental animals.

    PubMed

    Joshi, Ritu; Garabadu, Debapriya; Teja, Gangineni Ravi; Krishnamurthy, Sairam

    2014-12-01

    Neuroinflammation is considered as one of the predisposing factor in the etiology of several neurodegenerative disorders. Therefore, the objective of the present study was to evaluate the protective effect of silibinin (SIL) in the lipopolysaccharide (LPS)-induced neuroinflammatory model. The effect of SIL on memory function was also evaluated on normal rats without LPS administration. In the first experiment, male rats were divided into five groups. Except control group animals, all rats received bilateral intracerebroventricular injection of LPS (5 μg/5 μl) into lateral ventricles on the first day of the experimental schedule. Control rats received bilateral intracerebroventricular injection of artificial cerebrospinal fluid into lateral ventricles. SIL in doses of 50, 100 and 200 mg/kg, p.o. was administered 1h before LPS injection and continued for 7 days. On Day-7, SIL attenuated the LPS-induced long-term and working memory loss in elevated plus and Y-maze test respectively. Further, SIL dose-dependently attenuated LPS-induced decrease in acetylcholine level and increase in the acetylcholinestrase activity in hippocampus and pre-frontal cortex. SIL ameliorated LPS-induced decrease in the mitochondrial complex activity (I, IV and V) and integrity, increase in lipid peroxidation and decrease in the activity of superoxide dismutase in both the brain regions. SIL attenuated amyloidogenesis in the hippocampus, while it decreased the LPS-induced increase in the level of NFκB in the pre-frontal cortex. In another study, SIL dose-dependently, enhanced memory functions in the normal rats, indicating its nootropic activity. Hence, SIL could be a potential candidate in the management of neuroinflammation-related memory disorders.

  8. Experimental microembolism induces localized neuritic pathology in guinea pig cerebrum.

    PubMed

    Li, Jian-Ming; Cai, Yan; Liu, Fei; Yang, La; Hu, Xia; Patrylo, Peter R; Cai, Huaibin; Luo, Xue-Gang; Xiao, Dong; Yan, Xiao-Xin

    2015-05-10

    Microbleeds are a common finding in aged human brains. In Alzheimer's disease (AD), neuritic plaques composed of β-amyloid (Aβ) deposits and dystrophic neurites occur frequently around cerebral vasculature, raising a compelling question as to whether, and if so, how, microvascular abnormality and amyloid/neuritic pathology might be causally related. Here we used a guinea pig model of cerebral microembolism to explore a potential inductive effect of vascular injury on neuritic and amyloid pathogenesis. Brains were examined 7-30 days after experimental microvascular embolization occupying ~0.5% of total cortical area. Compared to sham-operated controls, glial fibrillary acidic protein immunoreactivity was increased in the embolized cerebrum, evidently around intracortical vasculature. Swollen/sprouting neurites exhibiting increased reactivity of nicotinamide adenine dinucleotide phosphate diaphorase, parvalbumin, vesicular glutamate transporter 1 and choline acetyltransferase appeared locally in the embolized brains in proximity to intracortical vasculature. The embolization-induced swollen/sprouting neurites were also robustly immunoreactive for β-amyloid precursor protein and β-secretase-1, the substrate and initiating enzyme for Aβ genesis. These experimental data suggest that microvascular injury can induce multisystem neuritic pathology associated with an enhanced amyloidogenic potential in wild-type mammalian brain.

  9. Experimental identification of pedestrian-induced lateral forces on footbridges

    NASA Astrophysics Data System (ADS)

    Ingólfsson, E. T.; Georgakis, C. T.; Ricciardelli, F.; Jönsson, J.

    2011-03-01

    This paper presents a comprehensive experimental analysis of lateral forces generated by single pedestrians during continuous walking on a treadmill. Two different conditions are investigated; initially the treadmill is fixed and then it is laterally driven in a sinusoidal motion at varying combinations of frequencies (0.33-1.07 Hz) and amplitudes (4.5-48 mm). The experimental campaign involved 71 male and female human adults and covered approximately 55 km of walking distributed between 4954 individual tests. When walking on a laterally moving surface, motion-induced forces develop at the frequency of the movement and are herewith quantified through equivalent velocity and acceleration proportional coefficients. Their dependency on the vibration frequency and amplitude is presented, both in terms of mean values and probabilistically to illustrate the randomness associated with intra- and inter-subject variability. It is shown that the motion-induced portion of the pedestrian load (on average) inputs energy into the structure in the frequency range (normalised by the mean walking frequency) between approximately 0.6 and 1.2. Furthermore, it is shown that the load component in phase with the acceleration of the treadmill depends on the frequency of the movement, such that pedestrians (on average) subtract from the overall modal mass for low frequency motion and add to the overall modal mass at higher frequencies.

  10. Helicobacter pylori-induced gastritis in experimentally infected conventional piglets.

    PubMed

    Poutahidis, T; Tsangaris, T; Kanakoudis, G; Vlemmas, I; Iliadis, N; Sofianou, D

    2001-11-01

    A conventional nonmutant animal that could be experimentally infected with Helicobacter pylori isolates would be a useful animal model for human H. pylori-associated gastritis. Gnotobiotic and barrier-born pigs are susceptible to H. pylori infection, but attempts to infect conventional pigs with this bacterium have been unsuccessful. In the present study, a litter of eight 20-day-old crossbreed piglets were purchased from a commercial farm. Six of them were orally challenged two to five times at different ages, between 29 and 49 days, with doses of H. pylori inoculum containing approximately 10(9) bacterial cells. Two animals served as controls. The inoculation program began 2 days postweaning when the piglets were 29 days of age. Prior to every inoculation, the piglets were fasted and pretreated with cimetidine, and prior to the first and second inoculation each piglet also was pretreated with dexamethasone. The challenged piglets were euthanasized between 36 and 76 days of age. H. pylori colonized all six inoculated piglets. The pathology of the experimentally induced gastritis was examined macroscopically and by light and electron microscopy. H. pylori induced a severe lymphocytic gastritis in the conventional piglets and reproduced the large majority of the pathologic features of the human disease. Therefore, the conventional piglet represents a promising new model for study of the various pathogenic mechanisms involved in the development of lesions of the human H. pylori-associated gastritis.

  11. The influence of experimentally induced pain on shoulder muscle activity.

    PubMed

    Diederichsen, Louise Pyndt; Winther, Annika; Dyhre-Poulsen, Poul; Krogsgaard, Michael R; Nørregaard, Jesper

    2009-04-01

    Muscle function is altered in painful shoulder conditions. However, the influence of shoulder pain on muscle coordination of the shoulder has not been fully clarified. The aim of the present study was to examine the effect of experimentally induced shoulder pain on shoulder muscle function. Eleven healthy men (range 22-27 years), with no history of shoulder or cervical problems, were included in the study. Pain was induced by 5% hypertonic saline injections into the supraspinatus muscle or subacromially. Seated in a shoulder machine, subjects performed standardized concentric abduction (0 degrees -105 degrees) at a speed of approximately 120 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 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 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 that acute pain both subacromially and in the supraspinatus muscle modulates coordination of the shoulder muscles during voluntary movements. During painful conditions, an increased activity was detected in the antagonist (latissimus), which support the idea that localized pain affects muscle activation in a way that protects the painful structure. Further, the changes in muscle activity following subacromial pain induction tend to expand the subacromial space and thereby decrease the load

  12. In vivo Expression of Inducible Nitric Oxide Synthase in Experimentally Induced Neurologic Diseases

    NASA Astrophysics Data System (ADS)

    Koprowski, Hilary; Zheng, Yong Mu; Heber-Katz, Ellen; Fraser, Nigel; Rorke, Lucy; Fu, Zhen Fang; Hanlon, Cathleen; Dietzschold, Bernhard

    1993-04-01

    The purpose of this study was to investigate the induction of inducible nitric oxide synthase (iNOS) mRNA in the brain tissue of rats and mice under the following experimental conditions: in rats infected with borna disease virus and rabies virus, in mice infected with herpes simplex virus, and in rats after the induction of experimental allergic encephalitis. The results showed that iNOS mRNA, normally nondetectable in the brain, was present in animals after viral infection or after induction of experimental allergic encephalitis. The induction of iNOS mRNA coincided with the severity of clinical signs and in some cases with the presence of inflammatory cells in the brain. The results indicate that nitric oxide produced by cells induced by iNOS may be the toxic factor accounting for cell damage and this may open the door to approaches to the study of the pathogenesis of neurological diseases.

  13. Practical Dyspnea Assessment: Relationship Between the 0–10 Numerical Rating Scale and the Four-Level Categorical Verbal Descriptor Scale of Dyspnea Intensity

    PubMed Central

    Wysham, Nicholas G.; Miriovsky, Benjamin J.; Currow, David C.; Herndon, James E.; Samsa, Gregory P.; Wilcock, Andrew; Abernethy, Amy P.

    2016-01-01

    Context Measurement of dyspnea is important for clinical care and research. Objectives To characterize the relationship between the 0–10 Numerical Rating Scale (NRS) and four-level categorical Verbal Descriptor Scale (VDS) for dyspnea assessment. Methods This was a substudy of a double-blind randomized controlled trial comparing palliative oxygen to room air for relief of refractory breathlessness in patients with life-limiting illness. Dyspnea was assessed with both a 0–10 NRS and a four-level categorical VDS over the one-week trial. NRS and VDS responses were analyzed in cross section and longitudinally. Relationships between NRS and VDS responses were portrayed using descriptive statistics and visual representations. Results Two hundred twenty-six participants contributed responses. At baseline, mild and moderate levels of breathlessness were reported by 41.9% and 44.6% of participants, respectively. NRS scores demonstrated increasing mean and median levels for increasing VDS intensity, from a mean (SD) of 0.6 (±1.04) for VDS none category to 8.2 (1.4) for VDS severe category. The Spearman correlation coefficient was strong at 0.78 (P < 0.0001). Based on the distribution of NRS scores within VDS categories, we calculated test characteristics of two different cutpoint models. Both models yielded 75% correct translations from NRS to VDS; however, Model A was more sensitive for moderate or greater dyspnea, with fewer misses downcoded. Conclusion There is strong correlation between VDS and NRS measures for dyspnea. Proposed practical cutpoints for the relationship between the dyspnea VDS and NRS are 0 for none, 1–4 for mild, 5–8 for moderate, and 9–10 for severe. PMID:26004401

  14. Mechanisms of blast induced brain injuries, experimental studies in rats.

    PubMed

    Risling, M; Plantman, S; Angeria, M; Rostami, E; Bellander, B-M; Kirkegaard, M; Arborelius, U; Davidsson, J

    2011-01-01

    Traumatic brain injuries (TBI) potentially induced by blast waves from detonations result in significant diagnostic problems. It may be assumed that several mechanisms contribute to the injury. This study is an attempt to characterize the presumed components of the blast induced TBI. Our experimental models include a blast tube in which an anesthetized rat can be exposed to controlled detonations of explosives that result in a pressure wave with a magnitude between 130 and 260 kPa. In this model, the animal is fixed with a metal net to avoid head acceleration forces. The second model is a controlled penetration of a 2mm thick needle. In the third model the animal is subjected to a high-speed sagittal rotation angular acceleration. Immunohistochemical labeling for amyloid precursor protein revealed signs of diffuse axonal injury (DAI) in the penetration and rotation models. Signs of punctuate inflammation were observed after focal and rotation injury. Exposure in the blast tube did not induce DAI or detectable cell death, but functional changes. Affymetrix Gene arrays showed changes in the expression in a large number of gene families including cell death, inflammation and neurotransmitters in the hippocampus after both acceleration and penetration injuries. Exposure to the primary blast wave induced limited shifts in gene expression in the hippocampus. The most interesting findings were a downregulation of genes involved in neurogenesis and synaptic transmission. These experiments indicate that rotational acceleration may be a critical factor for DAI and other acute changes after blast TBI. The further exploration of the mechanisms of blast TBI will have to include a search for long-term effects. PMID:20493951

  15. Numerical and Experimental Investigations of Tsunami-Induced Sediment Transport

    NASA Astrophysics Data System (ADS)

    Young, Y.; Xiao, H.

    2007-05-01

    As demonstrated by the 2004 Indian Ocean Tsunami, high intensity wave runup and drawdown can mobilize substantial amount of sediment deposits. The resulting erosion and scour damage can undermine building foundations, roadways, sea walls, embankments, and may even lead to eventual collapse of the coastal structure. However, most previous models ignore the effect of tsunami-induced sediment transport and scour due to the complex physics and multiple scaling issues. In this work, a numerical model is presented for the simulation of solitary waves over a uniform sloped movable bed. The depth averaged nonlinear shallow water equations (SWEs) are used to model long waves, the wave profile gradient method is used to detect wave breaking, and the effect of energy-dissipation due to wave breaking is captured as a bore collapse. The effect of sediment transport is modeled via a passive scalar and is fully coupled with the SWEs to form a complete system. New forms of the erosion and deposition fluxes are introduced to account for the effect of the flow velocity, particle fall velocity, wave profile, and pore pressure gradient. The model is validated by comparing the numerical solutions to the measured bed changes obtained from the cross-shore sediment transport experiment under breaking solitary waves conducted by (Kobayashi & Lawrence 2004). To further validate the numerical model, two sets of experimental studies are planned for 2007. The first experimental study focuses on the effect of enhanced transport due to pore pressure gradients, and will be conducted at the 30-ft long flume in the hydraulics lab at the University of Hawaii using multiple grain sizes. The second experimental study focuses on tsunami-induced sediment transport, and will be conducted at the 160-ft long tsunami wave basin at Oregon State University using fine Oregon beach sand with D50=0.20mm. The experimental setups are shown, and scaling issues for the two movable bed physical models are discussed

  16. The therapeutic use of music for dyspnea and anxiety in patients with COPD who live at home.

    PubMed

    McBride, S; Graydon, J; Sidani, S; Hall, L

    1999-09-01

    The purposes of this repeated measures study were to examine the feasibility of using music as an intervention for dyspnea and anxiety in patients with chronic obstructive pulmonary disease (COPD) who live in their homes and to examine the effect of music on anxiety and dyspnea. Twenty-four participants who experienced dyspnea at least once a week were studied over a 5-week period. Baseline data were collected on Week 1. Measures of anxiety and dyspnea were taken on Week 2, prior to and immediately following the use of music. These measures were repeated on Week 5. There was a significant decrease in dyspnea following the use of music as reported in the music diary (p < .001). There was a significant decline in anxiety (p < .05) and dyspnea (p < .01) following the use of music on Week 2. There was no significant change in anxiety or dyspnea over the 5-week period.

  17. Neurogenic cardiomyopathy in rabbits with experimentally induced rabies.

    PubMed

    Kesdangsakonwut, S; Sunden, Y; Yamada, K; Nishizono, A; Sawa, H; Umemura, T

    2015-05-01

    Cardiomyopathies have been rarely described in rabbits. Here we report myocardial necrosis of the ventricular wall in rabbits with experimentally induced rabies. Myocardial lesions were found only in rabbits with brain lesions, and the severity of the cardiac lesions was proportional to that of the brain lesions. Neither the frequency nor the cumulative dose of anesthesia was related to the incidence or the severity of the myocardial lesions. The myocardial lesions were characterized by degeneration and/or necrosis of myocardial cells and were accompanied by contraction band necrosis, interstitial fibrosis, and infiltration of inflammatory cells. The brain lesions due to rabies virus infection were most prominent in the cerebral cortex, thalamus, hypothalamus, brainstem, and medulla. Rabies virus antigen was not found in the hearts of any rabbits. Based on these findings, the myocardial lesions were classified as neurogenic cardiomyopathy.

  18. Dyspnea as a Prognostic Factor in Patients with Non-Small Cell Lung Cancer

    PubMed Central

    Ban, Wooho; Lee, Jong Min; Ha, Jick Hwan; Yeo, Chang Dong; Kang, Hyeon Hui; Rhee, Chin Kook; Moon, Hwa Sik

    2016-01-01

    Purpose To investigate associations between dyspnea and clinical outcomes in patients with non-small cell lung cancer (NSCLC). Materials and Methods From 2001 to 2014, we retrospectively reviewed the prospective lung cancer database of St. Paul's Hospital at the Catholic University of Korea. We enrolled patients with NSCLC and evaluated symptoms of dyspnea using modified Medical Research Council (mMRC) scores. Also, we estimated pulmonary functions and analyzed survival data. Results In total, 457 NSCLC patients were enrolled, and 259 (56.7%) had dyspnea. Among those with dyspnea and whose mMRC scores were available (109 patients had no mMRC score), 85 (56.6%) patients had an mMRC score <2, while 65 (43.3%) had an mMRC score ≥2. Significant decreased pulmonary functions were observed in patients with dyspnea. In multivariate analysis, aging, poor performance status, advanced stage, low forced expiratory volume in 1 second (%), and an mMRC score ≥2 were found to be significant prognostic factors for patient survival. Conclusion Dyspnea could be a significant prognostic factor in patients with NSCLC. PMID:27401635

  19. Laser-induced acoustic emissions in experimental dental composites.

    PubMed

    Lee, S Y; Lin, C T; Keh, E S; Pan, L C; Huang, H M; Shih, Y H; Cheng, H C

    2000-07-01

    A laser thermoacoustic technique was innovated to evaluate laser-induced acoustic emissions (AEs) in experimental dental composites aged with 75% ethanol solution. Experimental composite systems of 75/25 BisGMA/TEGDMA resin filled with 0, 12.6, 30.0, and 56.5 vol% of 8-microm silanized and unsilanized BaSiO6 were analyzed. The sample size was 4.65 mm (diameter) x 0.5 mm (thick). Aging effects of immersing in 75% ethanol for up to 14 h on AEs were then evaluated. A continuous-wave CO2 laser was used to heat the samples. Acoustic emissions were collected as a function of filler fraction, laser power, silanization, and immersion time. Onset of burst-pattern acoustic signals characteristic of fracturing occurred at different laser powers for different tested groups. Acoustic emissions generally increased with laser power, in which lower laser powers produced low-amplitude (45-50 dB) signals; the amplitude distribution (50-85 dB) became more extensive as laser powers increased. After immersion, the lower laser powers could produce the same phenomenon. The higher the filler fraction, the fewer AEs generated. A large percentage AE reduction due to silanization was noted as a function of filler fraction. Unsilanized specimens showed more thermal damages than did silanized ones.

  20. Bedside Ultrasonography versus Brain Natriuretic Peptide in Detecting Cardiogenic Causes of Acute Dyspnea

    PubMed Central

    Golshani, Keihan; Esmailian, Mehrdad; Valikhany, Aniseh; Zamani, Majid

    2016-01-01

    Introduction: Acute dyspnea is a common cause of hospitalization in emergency departments (ED).Distinguishing the cardiac causes of acute dyspnea from pulmonary ones is a major challenge for responsible physicians in EDs. This study compares the characteristics of bedside ultrasonography with serum level of blood natriuretic peptide (BNP) in this regard. Methods: This diagnostic accuracy study compares bedside ultrasonography with serum BNP levels in differentiating cardiogenic causes of acute respiratory distress. Echocardiography was considered as the reference test. A checklist including demographic data (age and sex), vital signs, medical history, underlying diseases, serum level of BNP, as well as findings of chest radiography, chest ultrasonography, and echocardiography was filled for all patients with acute onset of dyspnea. Screening characteristics of the two studied methods were calculated and compared using SPSS software, version 20. Results: 48 patients with acute respiratory distress were evaluated (50% female). The mean age of participants was 66.94 ± 16.33 (28-94) years. Based on the results of echocardiography and final diagnosis, the cause of dyspnea was cardiogenic in 20 (41.6%) cases. Bedside ultrasonography revealed the cardiogenic cause of acute dyspnea in 18 cases (0 false positive) and BNP in 44 cases (24 false positives). The area under the ROC curve for bedside ultrasonography and BNP for differentiating the cardiogenic cause of dyspnea were 86.4 (95% CI: 74.6-98.3) and 66.3 (95% CI: 49.8-89.2), respectively (p = 0.0021). Conclusion: It seems that bedside ultrasonography could be considered as a helpful and accurate method in differentiating cardiogenic causes of acute dyspnea in emergency settings. Nevertheless, more study is needed to make a runaway algorithm to evaluate patients with respiratory distress using bedside ultrasonography, which leads to rapid therapeutic decisions in a short time. PMID:27299143

  1. The effects of experimentally induced adelphophagy in gastropod embryos.

    PubMed

    Thomsen, Olaf; Collin, Rachel; Carrillo-Baltodano, Allan

    2014-01-01

    Adelphophagy, development where embryos grow large by consuming morphologically distinct nutritive embryos or their own normal siblings is widespread but uncommon among animal phyla. Among invertebrates it is particularly common in some families of marine gastropods and segmented worms, but rare or unknown in other closely related families. In calyptraeid gastropods phylogenetic analysis indicates that adelphophagy has arisen at least 9 times from species with planktotrophic larval development. This pattern of frequent parallel evolution of adelphophagy suggests that the embryos of planktotrophic species might be predisposed to evolve adelphophagy. Here we used embryos of three species of planktotrophic calyptraeids, one from each of three major genera in the family (Bostrycapulus, Crucibulum, and Crepidula), to answer the following 3 questions: (1) Can embryos of species with planktotrophic development benefit, in terms of pre-hatching growth, from the ingestion of yolk and tissue from experimentally damaged siblings? (2) Does ingestion of this material from damaged siblings increase variation in pre-hatching size? and (3) Does this experimentally induced adelphophagy alter the allometry between the velum and the shell, increasing morphological similarity to embryos of normally adelphophagic species? We found an overall increase in shell length and velum diameter when embryos feed on damaged siblings within their capsules. There was no detectable increase in variation in shell length or velum diameter, or changes in allometry. The overall effect of our treatment was small compared to the embryonic growth observed in naturally adelphophagic development. However each embryo in our experiment probably consumed less than one sibling on average, whereas natural adelphophages often each consume 10-30 or more siblings. These results suggest that the ability to consume, assimilate, and benefit from yolk and tissue of their siblings is widespread across calyptraeids.

  2. The Effects of Experimentally Induced Adelphophagy in Gastropod Embryos

    PubMed Central

    Thomsen, Olaf; Collin, Rachel; Carrillo-Baltodano, Allan

    2014-01-01

    Adelphophagy, development where embryos grow large by consuming morphologically distinct nutritive embryos or their own normal siblings is widespread but uncommon among animal phyla. Among invertebrates it is particularly common in some families of marine gastropods and segmented worms, but rare or unknown in other closely related families. In calyptraeid gastropods phylogenetic analysis indicates that adelphophagy has arisen at least 9 times from species with planktotrophic larval development. This pattern of frequent parallel evolution of adelphophagy suggests that the embryos of planktotrophic species might be predisposed to evolve adelphophagy. Here we used embryos of three species of planktotrophic calyptraeids, one from each of three major genera in the family (Bostrycapulus, Crucibulum, and Crepidula), to answer the following 3 questions: (1) Can embryos of species with planktotrophic development benefit, in terms of pre-hatching growth, from the ingestion of yolk and tissue from experimentally damaged siblings? (2) Does ingestion of this material from damaged siblings increase variation in pre-hatching size? and (3) Does this experimentally induced adelphophagy alter the allometry between the velum and the shell, increasing morphological similarity to embryos of normally adelphophagic species? We found an overall increase in shell length and velum diameter when embryos feed on damaged siblings within their capsules. There was no detectable increase in variation in shell length or velum diameter, or changes in allometry. The overall effect of our treatment was small compared to the embryonic growth observed in naturally adelphophagic development. However each embryo in our experiment probably consumed less than one sibling on average, whereas natural adelphophages often each consume 10–30 or more siblings. These results suggest that the ability to consume, assimilate, and benefit from yolk and tissue of their siblings is widespread across calyptraeids

  3. 4-nitroquinoline-1-oxide induced experimental oral carcinogenesis.

    PubMed

    Kanojia, Deepak; Vaidya, Milind M

    2006-08-01

    Human oral cancer is the sixth largest group of malignancies worldwide and single largest group of malignancies in the Indian subcontinent. Seventy percent of premalignant cancers appear from premalignant lesions. Only 8-10% of these lesions finally turn into malignancy. The appearance of these premalignant lesions is one distinct feature of human oral cancer. At present there is dearth of biomarkers to identify which of these lesions will turn into malignancy. Regional lymph node metastasis and locoregional recurrence are the major factors responsible for the limited survival of patients with oral cancer. Paucity of early diagnostic and prognostic markers is one of the contributory factors for higher mortality rates. Cancer is a multistep process and because of constrain in availability of human tissues from multiple stages of oral carcinogenesis including normal tissues, animal models are being widely used, aiming for the development of diagnostic and prognostic markers. A number of chemical carcinogens like coal tar, 20 methyl cholanthrene (20MC), 9,10-dimethyl-1,2-benzanthracene (DMBA) and 4-nitroquinoline-1-oxide (4NQO) have been used in experimental oral carcinogenesis. However, 4NQO is the preferred carcinogen apart from DMBA in the development of experimental oral carcinogenesis. 4NQO is a water soluble carcinogen, which induces tumors predominantly in the oral cavity. It produces all the stages of oral carcinogenesis and several lines of evidences suggest that similar histological as well as molecular changes are observed in the human system. In the present review an attempt has been made to collate the information available on mechanisms of action of 4NQO, studies carried out for the development of biomarkers and chemopreventives agents using 4NQO animal models. PMID:16448841

  4. The Cell Nucleus in Physiological and Experimentally Induced Hypometabolism

    NASA Astrophysics Data System (ADS)

    Malatesta, M.

    The main problem for manned space mission is, at present, represented by the mass penalty associated to the human presence. An efficient approach could be the induction of a hypometabolic stasis in the astronauts, thus drastically reducing the physical and psychological requirements of the crew. On the other hand, in the wild, a reduction in resource consumptions physiologi- cally occurs in certain animals which periodically enter hibernation, a hypometabolic state in which both the energy need and energy offer are kept at a minimum. During the last twelve years, we have been studying different tissues of hibernating dormice, with the aim of analyzing their features during the euthermia -hibernation-arousal cycle as well as getting insight into the mechanisms allowing adaptation to hypometabolism. We paid particular attention to the cell nucleus, as it is the site of chief metabolic functions, such as DNA replication and RNA transcription. Our observations revealed no significant modification in the basic features of cell nuclei during hibernation; however, the cell nuclei of hibernating dormice showed unusual nuclear bodies containing molecules involved in RNA pathways. Therefore, we supposed that they could represent storage/assembly sites of several factors for processing some RNA which could be slowly synthesised during hibernation and rapidly and abundantly released in early arousal in order to meet the increased metabolic needs of the cell. The nucleolus also underwent structural and molecular modifications during hibernation, maybe to continue important nucleolar functions, or, alternatively, permit a most efficient reactivation upon arousal. On the basis of the observations made in vivo , we recently tried to experimentally induce a reversible hypometabolic state in in vitro models, using cell lines derived from hibernating and non-hibernating species. By administering the synthetic opioid DADLE, we could significantly reduce both RNA transcrip- tion and

  5. Erythropoietin is a hypoxia inducible factor-induced protective molecule in experimental autoimmune neuritis.

    PubMed

    Luo, Bangwei; Jiang, Man; Yang, Xiaofeng; Zhang, Zhiyuan; Xiong, Jian; Schluesener, Hermann J; Zhang, Zhiren; Wu, Yuzhang

    2013-08-01

    Experimental autoimmune neuritis (EAN), an autoantigen-specific T-cell-mediated disease model for human demyelinating inflammatory disease of the peripheral nervous system, is characterized by self-limitation. Here we investigated the regulation and contribution of erythropoietin (EPO) in EAN self-limitation. In EAN sciatic nerves, hypoxia, and protein and mRNA levels of hypoxia-inducible factor 1α (HIF-1α), HIF-2α, EPO and EPO receptor (EPOR) were induced in parallel at disease peak phase but reduced at recovery periods. Further, the deactivation of HIF reduced EAN-induced EPO/EPOR upregulation in EAN, suggesting the central contribution of HIF to EPO/EPOR induction. The deactivation of EPOR signalling exacerbated EAN progression, implying that endogenous EPO contributed to EAN recovery. Exogenous EPO treatment greatly improved EAN recovery. In addition, EPO was shown to promote Schwann cell survival and myelin production. In EAN, EPO treatment inhibited lymphocyte proliferation and altered helper T cell differentiation by inducing increase of Foxp3(+)/CD4(+) regulatory T cells and decrease of IFN-γ(+)/CD4(+) Th1 cells. Furthermore, EPO inhibited inflammatory macrophage activation and promoted its phagocytic activity. In summary, our data demonstrated that EPO was induced in EAN by HIF and contributed to EAN recovery, and endogenous and exogenous EPO could effectively suppress EAN by attenuating inflammation and exerting direct cell protection, indicating that EPO contributes to the self-recovery of EAN and could be a potent candidate for treatment of autoimmune neuropathies. PMID:23603807

  6. Early corticosteroid administration in experimental radiation-induced heart disease

    SciTech Connect

    Reeves, W.C.; Stryker, J.A.; Abt, A.A.; Chung, C.K.; Whitesell, L.; Zelis, R.

    1980-02-01

    The ability of dexamethasone (DEX) to reduce the severity of the late stage of radiation-induced heart disease (RIHD) was assessed in 25 New Zealand white rabbits. Ten rabbits served as unirradiated controls (CONT). In Group A, seven rabbits received intravenous DEX prior to irradiation and every 24 hours for three consecutive days. DEX was not administered to the eight rabbits in Group B. At 100 days postirradiation, the severity of the late state was determined by microscopic examination (MICRO) for myocardial fibrosis and determination of myocardial hydroxyproline content (MHP). Myocardial fibrosis was evident in groups A (40%) and B (80%) while none was present in CONT by MICRO. One rabbit in Group B with no fibrosis by MICRO had abnormally increased MHP. MHP was significantly increased in Groups A and B, as compared to CONT (p < 0.01). In addition to less fibrosis by MICRO, Group A demonstrated a significant reduction of MHP when compared to Group B (p < 0.05). Determination of MHP may be superior to MICRO in the detection of the late stage of RIHD. Also, early DEX administration appears to reduce myocardial collagen content (fibrosis) in this experimental model.

  7. Dyspnea and quality of life indicators in hospice patients and their caregivers

    PubMed Central

    Moody, Linda E; McMillan, Susan

    2003-01-01

    This study describes the assessment of dyspnea, symptom distress, and quality of life measures in 163 hospice patients with cancer who reported dyspnea. Mean age of the hospice patient sample was 70.22 years and 61.86 for caregivers (65% were spouses). The majority of patients and caregivers were white: 87%, 63% of the patients were male while 78% of caregivers were female. Mean dyspnea intensity as reported by patients was 4.52 (SD 2.29) and caregivers, 4.39 (SD 2.93). Patients' and caregivers' ratings of the patient's dyspnea intensity revealed no significant differences in ratings thus verifying that caregivers can assess dyspnea severity accurately. Patients' perceived quality of life ratings were not significantly correlated with ratings of their caregivers' perceived quality of life. For patients, symptom distress and education were significant predictors of variance in quality of life (R2 = .35, p = .04). However, mastery, symptom distress, age, and education were found to be significant predictors of variance in quality of life of caregivers (R2 = .40, p = .02). PMID:12740034

  8. Sequential occurrence of dyspnea at the end of life in palliative care, according to the underlying cancer

    PubMed Central

    Guirimand, Frédéric; Sahut d'izarn, Marine; Laporte, Lucy; Francillard, Marie; Richard, Jean-François; Aegerter, Philippe

    2015-01-01

    Dyspnea is a symptom that severely affects the quality of life of terminally ill patients. Its frequency differs considerably between studies. We aimed to characterize the frequency of dyspnea in a palliative care hospital (PCH) and to identify factors predisposing to dyspnea, particularly during the very last days of life, as a function of the underlying disease. Episodes of dyspnea were identified by the computerized extraction of prospectively collected data from the reports of care assistants or from medical observations recorded in the medical files for all stays at our PCH during the last 6 years. There were 6455 hospital stays, 88% ending in the death of the patient; 13,282 episodes of dyspnea were recorded during 2608 hospital stays (40%). Dyspnea was more frequently observed in cases of cancer than in other conditions (RR = 1.30; 95% CI: 1.14–1.48). Pulmonary metastasis increased the risk of dyspnea from 37% to 51% (RR = 1.37; 95% CI: 1.29–1.46). Dyspnea frequency varied with the primary cancer site, from 24% (brain cancer) to 60% (esophageal cancer). The data for cancer patients staying for more than 6 days who subsequently died indicated that 8% of patients experienced dyspnea exclusively during the last 4 days of the life, independently of the site of the primary cancer. Dyspnea during the last few days of life requires systematic assessment. Exclusively terminal dyspnea should be distinguished from more precocious dyspnea, as the pathophysiological mechanisms and treatments of these two forms are probably different. PMID:25644607

  9. Experimental validation of a numerical model for subway induced vibrations

    NASA Astrophysics Data System (ADS)

    Gupta, S.; Degrande, G.; Lombaert, G.

    2009-04-01

    This paper presents the experimental validation of a coupled periodic finite element-boundary element model for the prediction of subway induced vibrations. The model fully accounts for the dynamic interaction between the train, the track, the tunnel and the soil. The periodicity or invariance of the tunnel and the soil in the longitudinal direction is exploited using the Floquet transformation, which allows for an efficient formulation in the frequency-wavenumber domain. A general analytical formulation is used to compute the response of three-dimensional invariant or periodic media that are excited by moving loads. The numerical model is validated by means of several experiments that have been performed at a site in Regent's Park on the Bakerloo line of London Underground. Vibration measurements have been performed on the axle boxes of the train, on the rail, the tunnel invert and the tunnel wall, and in the free field, both at the surface and at a depth of 15 m. Prior to these vibration measurements, the dynamic soil characteristics and the track characteristics have been determined. The Bakerloo line tunnel of London Underground has been modelled using the coupled periodic finite element-boundary element approach and free field vibrations due to the passage of a train at different speeds have been predicted and compared to the measurements. The correspondence between the predicted and measured response in the tunnel is reasonably good, although some differences are observed in the free field. The discrepancies are explained on the basis of various uncertainties involved in the problem. The variation in the response with train speed is similar for the measurements as well as the predictions. This study demonstrates the applicability of the coupled periodic finite element-boundary element model to make realistic predictions of the vibrations from underground railways.

  10. Development of a Barthel Index based on dyspnea for patients with respiratory diseases

    PubMed Central

    Vitacca, Michele; Paneroni, Mara; Baiardi, Paola; De Carolis, Vito; Zampogna, Elisabetta; Belli, Stefano; Carone, Mauro; Spanevello, Antonio; Balbi, Bruno; Bertolotti, Giorgio

    2016-01-01

    Background As Barthel Index (BI) quantifies motor impairment but not breathlessness, the use of only this index could underestimate disability in chronic respiratory disease (CRD). To our knowledge, no study evaluates both motor and respiratory disability in CRD during activities of daily living (ADLs) simultaneously and with a unique tool. The objective of this study was to propose for patients with CRD an additional tool for dyspnea assessment during ADLs based on BI items named Barthel Index dyspnea. Methods Comprehensibility, reliability, internal consistency, validity, responsiveness, and ability to differentiate between disease groups were assessed on 219 subjects through an observational study performed in an in-hospital rehabilitation setting. Results Good comprehensibility, high reliability (interrater intraclass correlation coefficient was 0.93 [95% confidence interval 0.892–0.964] and test–retest intraclass correlation coefficient was 0.99 [95% confidence interval 0.983–0.994]), good internal consistency (Cronbach’s alpha 0.89), strong concurrent validity with 6 minute walking distance (Pearson r=−0.538, P<0.001) and Medical Research Council (Spearman rS=0.70, P<0.001), good responsiveness after rehabilitation (P<0.001), and good appropriateness of the index were found evidencing patients with different dyspnea severity. Divergent validity showed weak correlation (Pearson r=−0.38) comparing Barthel Index dyspnea and BI. Conclusion The BI based on dyspnea perception proved to be reliable, sensitive, and adequate as a tool for measuring the level of dyspnea perceived in performing basic daily living activities. A unique instrument simultaneously administered may provide a global assessment of disability during ADLs incorporating both motor and respiratory aspects. PMID:27354778

  11. Dyspnea, depression and health related quality of life in pulmonary arterial hypertension patients

    PubMed Central

    Talwar, Arunabh; Sahni, Sonu; Kim, Eun Ji; Verma, Sameer; Kohn, Nina

    2015-01-01

    Pulmonary arterial hypertension (PAH) is a rare and devastating disease which is characterized by worsening dyspnea and exercise tolerance. These patients are often found to have concomitant, depression, anxiety and impaired health-related quality of life (HRQOL). The interrelationship of dyspnea, depression and HRQOL in these patients is not well studied. Retrospective analysis was performed on 46 PAH patients (mean age 51.73). Patients completed Medical Outcomes Study Short - Form 36 V2 (SF-36) to measure HRQOL, Modified Medical Research Council (mMRC) Dyspnea Scale and Zung Depression Scale (ZDS). Physical Health Composite Scores (PCS) and Mental Health Composite Scores (MCS) were derived from SF-36. Spearman’s correlation was computed to determine degree of correlation between pairs of scales. 46 patients (12 males, 34 females; median age 51.4 yr) with confirmed PAH were considered for the study of which 36 patients (9 males, 27 females, median age 50.1 yr), were eligible for further analysis. MMRC Dyspnea Scale Score was 1.0 (Q1 to Q3:1.0 to 2.0). Median MCS was 52.1 (Q1 to Q3:41.7 to 57.1) and PCS was 37.9 (Q1 to Q3: 30.7 to 49.6). There was a significant negative correlation between dyspnea and PCS (r =−0.660, P<0.0001) and MCS (r =−0.342, P<0.0411). The ZDS was available for 17 of these patients; their median score was 42.0 (Q1 to Q3: 33.0 to 46.0). There was a significant correlation between the ZDS and PCS (r =−0.578, P<0.0150,) MCS (r =−0.752, P<0.0005). Patients with PAH suffer from diminished HRQOL correlating with their dyspnea and underlying depression. PMID:26535216

  12. Graded comprehensive cardiopulmonary exercise testing in the evaluation of dyspnea unexplained by routine evaluation.

    PubMed

    Martinez, F J; Stanopoulos, I; Acero, R; Becker, F S; Pickering, R; Beamis, J F

    1994-01-01

    The evaluation of dyspnea is problematic when a cause is inapparent after initial diagnostic studies. We examined the results and role of cardiopulmonary exercise testing (CPET) in 50 patients with a mean 23 months of dyspnea and normal FEV1 and FVC. The CPET studies were interpreted by a panel and a consensus reached. Subsequent tests ordered by the primary physician were reviewed, and a final diagnosis was agreed on by the panel. Seven of 50 patients had cardiac limitation, 17 of 50 had pulmonary limitation, 14 of 50 had obesity and/or deconditioning, 1 of 50 had gastroesophageal reflux, and 16 of 50 had either psychogenic dyspnea or no identifiable disease. Five patients had more than one clinical diagnosis accounting for 55 diagnoses in the 50 patients. Those with a normal CPET had a higher VO2max and O2 pulse than those with cardiac disease, deconditioning, or hyperactive airways disease (HAD) (p < 0.05). Electrocardiographic changes identified cardiac disease while studies demonstrating ventilatory limitation identified a pulmonary process. In 24, deconditioning could not be distinguished from cardiac limitation. Of these, 14 responded to exercise training and/or weight loss, whereas 3 had cardiac disease, 7 had HAD, and 4 had psychogenic dyspnea (4 had more than one clinical diagnosis). In the 13 patients with normal CPET results, one had gastroesophageal reflux, two had HAD, four had psychogenic dyspnea, and six had no identifiable disease. We conclude that a diagnosis can be made in most patients with chronic dyspnea; however, further studies including bronchoprovocation are often required. Cardiopulmonary exercise testing is useful in identifying a cardiac or pulmonary process, but it is insensitive in distinguishing cardiac disease from deconditioning.

  13. Astigmatism in Monkeys with Experimentally Induced Myopia or Hyperopia

    PubMed Central

    KEE, CHEA-SU; HUNG, LI-FANG; QIAO-GRIDER, YING; RAMAMIRTHAM, RAMKUMAR; SMITH, EARL L.

    2006-01-01

    Purpose Astigmatism is the most common ametropia found in humans and is often associated with large spherical ametropias. However, little is known about the etiology of astigmatism or the reason(s) for the association between spherical and astigmatic refractive errors. This study examines the frequency and characteristics of astigmatism in infant monkeys that developed axial ametropias as a result of altered early visual experience. Methods Data were obtained from 112 rhesus monkeys that experienced a variety of lens-rearing regimens that were intended to alter the normal course of emmetropization. These visual manipulations included form deprivation (n = 13); optically imposed defocus (n = 48); and continuous ambient lighting with (n = 6) or without optically imposed defocus (n = 6). In addition, data from 19 control monkeys and 39 infants reared with an optically imposed astigmatism were used for comparison purposes. The lens-rearing period started at approximately 3 weeks of age and ended by 4 to 5 months of age. Refractive development for all monkeys was assessed periodically throughout the treatment and subsequent recovery periods by retinoscopy, keratometry, and A-scan ultrasonography. Results In contrast to control monkeys, the monkeys that had experimentally induced axial ametropias frequently developed significant amounts of astigmatism (mean refractive astigmatism = 0.37 ± 0.33 D [control] vs. 1.24 ± 0.81 D [treated]; two-sample t-test, p < 0.0001), especially when their eyes exhibited relative hyperopic shifts in refractive error. The astigmatism was corneal in origin (Pearson’s r; p < 0.001 for total astigmatism and the JO and J45 components), and the axes of the astigmatism were typically oblique and bilaterally mirror symmetric. Interestingly, the astigmatism was not permanent; the majority of the monkeys exhibited substantial reductions in the amount of astigmatism at or near the end of the lens-rearing procedures. Conclusions In infant monkeys

  14. A 57-Year-Old Man With Insidious Dyspnea and Nonpleuritic Chest and Back Pain.

    PubMed

    Nakamura, Kenta; Alba, George A; Scheske, Jonathan A; Meyersohn, Nandini M; Stone, James R; Vlahakes, Gus J; Wright, Cameron D; Ghoshhajra, Brian B; Dudzinski, David M

    2016-08-01

    A 57-year-old man with a history of DVT and pulmonary embolism, transient ischemic attacks, prior 60 pack-year smoking history, and oxygen-dependent COPD presented with insidiously worsening dyspnea associated with new pleuritic chest and back pain. PMID:27502992

  15. Activity limitation and exertional dyspnea in adult asthmatic patients: What do we know?

    PubMed

    Vermeulen, François; Garcia, Gilles; Ninane, Vincent; Laveneziana, Pierantonio

    2016-08-01

    Limitation of activity is the most cited symptom described by uncontrolled asthma patients. Assessment of activity limitation can be undertaken through several ways, more or less complex, subjective or objective. Yet little is known about the link between patients sensations and objective measurements. The present review reports the current knowledge regarding activity limitation and symptom perception (i.e., exertional dyspnea) in adult patients with asthma. This work is based on references indexed by PubMed, irrespective of the year of publication. Overall, patients with stable asthma do not have a more sedentary lifestyle than healthy subjects. However, during a cycle ergometric test, the maximal load is reduced when FEV1, FVC and muscle strengths are decreased. Additionally, during the six-minute walking test, mild asthma patients walk less than healthy subjects even if the minimal clinically important difference is not reached. The major complaint of asthma patients when exercising is dyspnea that is mainly related to the inspiratory effort and also to dynamic hyperinflation in some circumstances. Finally, the administration of bronchodilator does not improve the ventilatory pattern and the exercise capacity of asthma patients and little is known on its effect on exertional dyspnea. The present review allows to conclude that until now there is no gold standard test allowing the objective assessment of "activity limitation and exertional dyspnea" in asthma patients. PMID:27492522

  16. Dyspnea-12 Is a Valid and Reliable Measure of Breathlessness in Patients With Interstitial Lung Disease

    PubMed Central

    Swigris, Jeffrey; Russell, Anne-Marie; Moosavi, Shakeeb H.; Ng Man Kwong, Georges; Longshaw, Mark; Jones, Paul W.

    2011-01-01

    Objective: In this study, we aimed to determine the validity and reliability of the Dyspnea-12 questionnaire (D-12) for the assessment of breathlessness in patients with interstitial lung disease (ILD). Methods: A total of 101 patients with ILD completed the D-12 (scale range, 0-36, with a high score indicating worse dyspnea), Medical Research Council (MRC) dyspnea scale, St. George Respiratory Questionnaire (SGRQ), and Hospital Anxiety and Depression Scale (HADS) at baseline, and 84 patients completed the D-12 and a global health transition score at follow-up 2 weeks later. D-12 psychometric properties, including floor and ceiling effects, internal consistency, test-retest reliability, and construct validity were examined. Results: The D-12 showed good internal consistency (Cronbach α, 0.93) and repeatability (intraclass correlation coefficient, 0.94). Its scores were significantly associated with MRC grade (r = 0.59; P < .001), SGRQ (symptoms, r = 0.57; activities, r = 0.78; impacts, r = 0.75; total, r = 0.79; P < .001). Factor analysis confirmed the previously determined structure of the D-12 in this patient group. Conclusion: In patients with ILD, the D-12, a patient-reported measure of dyspnea severity that requires no reference to activity, is a reliable and valid instrument. It is short, simple to complete, and easy to score. PMID:20595454

  17. Effects of changes in level and pattern of breathing on the sensation of dyspnea.

    PubMed

    Chonan, T; Mulholland, M B; Altose, M D; Cherniack, N S

    1990-10-01

    Breathing during hypercapnia is determined by reflex mechanisms but may also be influenced by respiratory sensations. The present study examined the effects of voluntary changes in level and pattern of breathing on the sensation of dyspnea at a constant level of chemical drive. Studies were carried out in 15 normal male subjects during steady-state hypercapnia at an end-tidal PCO2 of 50 Torr. The intensity of dyspnea was rated on a Borg category scale. In one experiment (n = 8), the level of ventilation was increased or decreased from the spontaneously adopted level (Vspont). In another experiment (n = 9), the minute ventilation was maintained at the level spontaneously adopted at PCO2 of 50 Torr and breathing frequency was increased or decreased from the spontaneously adopted level (fspont) with reciprocal changes in tidal volume. The intensity of dyspnea (expressed as percentage of the spontaneous breathing level) correlated with ventilation (% Vspont) negatively at levels below Vspont (r = -0.70, P less than 0.001) and positively above Vspont (r = 0.80, P less than 0.001). At a constant level of ventilation, the intensity of dyspnea correlated with breathing frequency (% fspont) negatively at levels below fspont (r = -0.69, P less than 0.001) and positively at levels above fspont (r = 0.75, P less than 0.001). These results indicate that dyspnea intensifies when the level or pattern of breathing is voluntarily changed from the spontaneously adopted level. This is consistent with the possibility that ventilatory responses to changes in chemical drive may be regulated in part to minimize the sensations of respiratory effort and discomfort.

  18. Accuracy of Nurse-Performed Lung Ultrasound in Patients With Acute Dyspnea: A Prospective Observational Study.

    PubMed

    Mumoli, Nicola; Vitale, Josè; Giorgi-Pierfranceschi, Matteo; Cresci, Alessandra; Cei, Marco; Basile, Valentina; Brondi, Barbara; Russo, Elisa; Giuntini, Lucia; Masi, Lorenzo; Cocciolo, Massimo; Dentali, Francesco

    2016-03-01

    In clinical practice lung ultrasound (LUS) is becoming an easy and reliable noninvasive tool for the evaluation of dyspnea. The aim of this study was to assess the accuracy of nurse-performed LUS, in particular, in the diagnosis of acute cardiogenic pulmonary congestion. We prospectively evaluated all the consecutive patients admitted for dyspnea in our Medicine Department between April and July 2014. At admission, serum brain natriuretic peptide (BNP) levels and LUS was performed by trained nurses blinded to clinical and laboratory data. The accuracy of nurse-performed LUS alone and combined with BNP for the diagnosis of acute cardiogenic dyspnea was calculated. Two hundred twenty-six patients (41.6% men, mean age 78.7 ± 12.7 years) were included in the study. Nurse-performed LUS alone had a sensitivity of 95.3% (95% CI: 92.6-98.1%), a specificity of 88.2% (95% CI: 84.0-92.4%), a positive predictive value of 87.9% (95% CI: 83.7-92.2%) and a negative predictive value of 95.5% (95% CI: 92.7-98.2%). The combination of nurse-performed LUS with BNP level (cut-off 400 pg/mL) resulted in a higher sensitivity (98.9%, 95% CI: 97.4-100%), negative predictive value (98.8%, 95% CI: 97.2-100%), and corresponding negative likelihood ratio (0.01, 95% CI: 0.0, 0.07). Nurse-performed LUS had a good accuracy in the diagnosis of acute cardiogenic dyspnea. Use of this technique in combination with BNP seems to be useful in ruling out cardiogenic dyspnea. Other studies are warranted to confirm our preliminary findings and to establish the role of this tool in other settings. PMID:26945396

  19. Accuracy of Nurse-Performed Lung Ultrasound in Patients With Acute Dyspnea

    PubMed Central

    Mumoli, Nicola; Vitale, Josè; Giorgi-Pierfranceschi, Matteo; Cresci, Alessandra; Cei, Marco; Basile, Valentina; Brondi, Barbara; Russo, Elisa; Giuntini, Lucia; Masi, Lorenzo; Cocciolo, Massimo; Dentali, Francesco

    2016-01-01

    Abstract In clinical practice lung ultrasound (LUS) is becoming an easy and reliable noninvasive tool for the evaluation of dyspnea. The aim of this study was to assess the accuracy of nurse-performed LUS, in particular, in the diagnosis of acute cardiogenic pulmonary congestion. We prospectively evaluated all the consecutive patients admitted for dyspnea in our Medicine Department between April and July 2014. At admission, serum brain natriuretic peptide (BNP) levels and LUS was performed by trained nurses blinded to clinical and laboratory data. The accuracy of nurse-performed LUS alone and combined with BNP for the diagnosis of acute cardiogenic dyspnea was calculated. Two hundred twenty-six patients (41.6% men, mean age 78.7 ± 12.7 years) were included in the study. Nurse-performed LUS alone had a sensitivity of 95.3% (95% CI: 92.6–98.1%), a specificity of 88.2% (95% CI: 84.0–92.4%), a positive predictive value of 87.9% (95% CI: 83.7–92.2%) and a negative predictive value of 95.5% (95% CI: 92.7–98.2%). The combination of nurse-performed LUS with BNP level (cut-off 400 pg/mL) resulted in a higher sensitivity (98.9%, 95% CI: 97.4–100%), negative predictive value (98.8%, 95% CI: 97.2–100%), and corresponding negative likelihood ratio (0.01, 95% CI: 0.0, 0.07). Nurse-performed LUS had a good accuracy in the diagnosis of acute cardiogenic dyspnea. Use of this technique in combination with BNP seems to be useful in ruling out cardiogenic dyspnea. Other studies are warranted to confirm our preliminary findings and to establish the role of this tool in other settings. PMID:26945396

  20. Physiological mechanisms of dyspnea during exercise with external thoracic restriction: role of increased neural respiratory drive.

    PubMed

    Mendonca, Cassandra T; Schaeffer, Michele R; Riley, Patrick; Jensen, Dennis

    2014-03-01

    We tested the hypothesis that neuromechanical uncoupling of the respiratory system forms the mechanistic basis of dyspnea during exercise in the setting of "abnormal" restrictive constraints on ventilation (VE). To this end, we examined the effect of chest wall strapping (CWS) sufficient to mimic a "mild" restrictive lung deficit on the interrelationships between VE, breathing pattern, dynamic operating lung volumes, esophageal electrode-balloon catheter-derived measures of the diaphragm electromyogram (EMGdi) and the transdiaphragmatic pressure time product (PTPdi), and sensory intensity and unpleasantness ratings of dyspnea during exercise. Twenty healthy men aged 25.7 ± 1.1 years (means ± SE) completed symptom-limited incremental cycle exercise tests under two randomized conditions: unrestricted control and CWS to reduce vital capacity (VC) by 21.6 ± 0.5%. Compared with control, exercise with CWS was associated with 1) an exaggerated EMGdi and PTPdi response; 2) no change in the relationship between EMGdi and each of tidal volume (expressed as a percentage of VC), inspiratory reserve volume, and PTPdi, thus indicating relative preservation of neuromechanical coupling; 3) increased sensory intensity and unpleasantness ratings of dyspnea; and 4) no change in the relationship between increasing EMGdi and each of the intensity and unpleasantness of dyspnea. In conclusion, the increased intensity and unpleasantness of dyspnea during exercise with CWS could not be readily explained by increased neuromechanical uncoupling but likely reflected the awareness of increased neural respiratory drive (EMGdi) needed to achieve any given VE during exercise in the setting of "abnormal" restrictive constraints on tidal volume expansion.

  1. Caring for dying patients in the intensive care unit: managing pain, dyspnea, anxiety, delirium, and death rattle.

    PubMed

    Campbell, Margaret L

    2015-01-01

    Critically ill patients receiving palliative care at the end of life are at high risk for experiencing pain, dyspnea, and death rattle. Nearly all these patients are at risk for the development of delirium. Patients who are alert may experience anxiety. Advanced practice nurses and staff nurses are integral to detecting and treating these symptoms. Pain, dyspnea, and anxiety should be routinely assessed by patient self-report when possible. Routine behavioral screening for delirium is recommended. Behavioral observation tools to detect pain and dyspnea and proxy assessments guide symptom identification when the patient cannot provide a self-report. Evidence-based interventions are offered for both prevention and treatment of pain, dyspnea, anxiety, and delirium. Death rattle does not produce patient distress, and current pharmacological treatment lacks an evidence base. Pain management has a robust evidence base compared to management of dyspnea, anxiety, and delirium among this population; well-designed, adequately powered studies are needed.

  2. Impact of blunted perception of dyspnea on medical care use and expenditure, and mortality in elderly people.

    PubMed

    Ebihara, Satoru; Niu, Kaijun; Ebihara, Takae; Kuriyama, Shinichi; Hozawa, Atsushi; Ohmori-Matsuda, Kaori; Nakaya, Naoki; Nagatomi, Ryoichi; Arai, Hiroyuki; Kohzuki, Masahiro; Tsuji, Ichiro

    2012-01-01

    Dyspnea is an alarming symptom responsible for millions of patient visits each year. Poor perception of dyspnea might be reasonably attributed to an inappropriately low level of fear and inadequate earlier medical treatment for both patients and physicians, resulting in subsequent intensive care. This study was conducted to evaluate medical care use and cost, and mortality according to the perception of dyspnea in community-dwelling elderly people. We analyzed baseline data from a community-based Comprehensive Geriatric Assessment in 2002. The perception of dyspnea in 479 Japanese community-dwelling elderly people with normal lung function was measured in August 2002. The sensation of dyspnea during breathing with a linear inspiratory resistance of 10, 20, and 30 cmH(2)O/L/s was rated using the Borg scale. According to the perception of dyspnea, we divided the elderly into tertiles and compared all hospitalizations, out-patient visits, costs, and death through computerized linkage with National Health Insurance beneficiaries claims history files between August 2002 and March 2008. In-patient hospitalization days and medical care costs significantly increased with the blunted perception of dyspnea, resulting in an increase in total medical-costs with blunted perception of dyspnea. With low perception group as reference, the hazard ratios of all-cause mortality were 0.65 (95% CI 0.23-1.89) for intermediate perception group and 0.31 (0.10-0.97) for high perception group, indicating the mortality rate also significantly increased with the blunted perception of dyspnea after multivariates adjustment (p = 0.04). The blunted perception of dyspnea is related to hospitalization, large medical costs, and all-cause mortality in community-dwelling elderly people. These findings provide a rational for preventing serious illness with careful monitoring of objective conditions in the elderly.

  3. Effects of dead space loading on neuro-muscular and neuro-ventilatory coupling of the respiratory system during exercise in healthy adults: implications for dyspnea and exercise tolerance.

    PubMed

    Jensen, Dennis; O'Donnell, Denis E; Li, Ruifa; Luo, Yuan-Ming

    2011-12-15

    We examined the effects of dead space loading (DSL) on ventilation (V˙E), neural respiratory drive (EMGdi%max, diaphragm EMG expressed as a % of maximal EMGdi), contractile respiratory muscle effort (Pes,tidal%P(Imax), tidal esophageal pressure swing expressed as a % of maximal inspiratory Pes) and exertional dyspnea intensity ratings in 11 healthy adults with normal spirometry. Subjects completed, in random order, symptom-limited incremental cycle exercise tests under control (CTRL) and DSL (500 ml) conditions. Compared with CTRL, DSL decreased exercise tolerance by 20-25%; increased exertional dyspnea intensity ratings in direct proportion to concurrent increases in EMGdi%max, Pes,tidal%P(Imax) and V˙E; and had little/no effect on the inter-relationships between EMGdi%max, Pes,tidal%P(Imax) and V˙E during exercise. In conclusion, DSL was associated with an earlier onset of intolerable dyspnea; however, neuro-muscular and neuro-ventilatory coupling of the respiratory system remained relatively preserved during exercise in the presence of an increased external dead space. Under these circumstances, DSL-induced increases in exertional dyspnea intensity ratings reflected, at least in part, the awareness of increased neural respiratory drive, contractile respiratory muscle effort and ventilatory output.

  4. Experimentally Induced Empathy and Its Role in Reducing Aggression.

    ERIC Educational Resources Information Center

    Greene, Richard J.; And Others

    This study attempted to induce empathy toward a hypothetical individual in an effort to reduce aggressive responses directed toward him. Forty fourth grade volunteer boys from two Michigan public schools were administered the Index of Empathy for Children and Adolescents to determine pre-existing empathic potential (EP). Subjects were matched for…

  5. Induced thermoluminescence study of experimentally shock-loaded oligoclase

    NASA Technical Reports Server (NTRS)

    Ivliev, A. I.; Kashkarov, L. L.; Badjukov, D. D.

    1993-01-01

    Artificially induced thermoluminescence (TL) in oligoclase samples which were shock-loaded up to 27 GPa was measured. The essential increase of the TL sensitivity in relation to the total gamma-ray irradiation dose was observed only in samples at the 27 GPa pressure. This result can be explained by the initiation of additional radiation damages in the shocked oligoclace crystal lattice.

  6. Experimental Feedback Control of Flow Induced Cavity Tones

    NASA Technical Reports Server (NTRS)

    Cabell, Randolph H.; Kegerise, Michael A.; Cox, David E.; Gibbs, Gary P.

    2002-01-01

    An experimental study of the application of discrete-time, linear quadratic control design methods to the cavity tone problem is described. State space models of the dynamics from a synthetic jet actuator at the leading edge of the cavity to two pressure sensors in the cavity were computed from experimental data. Variations in model order, control order, control bandwidth, and properties of a Kalman state estimator were studied. Feedback control reduced the levels of multiple cavity tones at Mach 0.275, 0.35, and 0.45. Closed loop performance was often limited by excitation of sidebands of cavity tones, and creation of new tones in the spectrum. State space models were useful for explaining some of these limitations, but were not able to account for non-linear dynamics, such as interactions between tones at different frequencies.

  7. Comparison of methods for evaluation of experimentally induced emphysema

    SciTech Connect

    Busch, R.H.; Buschbom, R.L.; Smith, L.G.

    1984-04-01

    Four methods to quantify induced emphysema, in a manner economically applicable to large numbers of animals, are compared by correlation analyses. Lung tissue used was from rats pretreated intratracheally with elastase or saline prior to exposure to air or (NH/sub 4/)/sub 2/SO/sub 4/ or NH/sub 4/NO/sub 3/ aerosols. The most sensitive quantitative evaluation was from mean chord length (MCL) measurements on scanning electron micrographs (SEM). Four-corner and parallel-line grids provided similar results, and reducing sample size to one selected field per lobe yielded a high degree of reliability for MCL measurements. Alveolar-pore perimeter and area (also measured on SEM photographs) were increased by induced emphysema, but were not reliable indicators for degree of pulmonary involvement. Both subjective score (grading the degree of emphysema) and percentage-area-affected determinations indicated the presence of emphysema, but with less sensitivity than MCL measurements. However, these two subgross methods (performed with a dissecting microscope) provided valuable information on the distribution of pulmonary lesions; emphysema was induced in a nonuniform but consistent and progressive pattern in the two lobes of the lung studied. 23 studied.

  8. Interleukin 19 reduces inflammation in chemically induced experimental colitis.

    PubMed

    Matsuo, Yukiko; Azuma, Yasu-Taka; Kuwamura, Mitsuru; Kuramoto, Nobuyuki; Nishiyama, Kazuhiro; Yoshida, Natsuho; Ikeda, Yoshihito; Fujimoto, Yasuyuki; Nakajima, Hidemitsu; Takeuchi, Tadayoshi

    2015-12-01

    Inflammatory bowel disease results from chronic dysregulation of the mucosal immune system and aberrant activation of both the innate and adaptive immune responses. Interleukin (IL)-19, a member of the IL-10 family, functions as an anti-inflammatory cytokine. Here, we investigated the contribution of IL-19 to intestinal inflammation in a model of T cell-mediated colitis in mice. Inflammatory responses in IL-19-deficient mice were assessed using the 2,4,6-trinitrobenzene sulfonic acid (TNBS) model of acute colitis. IL-19 deficiency aggravated TNBS-induced colitis and compromised intestinal recovery in mice. Additionally, the exacerbation of TNBS-induced colonic inflammation following genetic ablation of IL-19 was accompanied by increased production of interferon-gamma, IL-12 (p40), IL-17, IL-22, and IL-33, and decreased production of IL-4. Moreover, the exacerbation of colitis following IL-19 knockout was also accompanied by increased production of CXCL1, G-CSF and CCL5. Using this model of induced colitis, our results revealed the immunopathological relevance of IL-19 as an anti-inflammatory cytokine in intestinal inflammation in mice.

  9. Experimental study of microwave-induced thermoacoustic imaging

    NASA Astrophysics Data System (ADS)

    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.

  10. Acute phase proteins in experimentally induced pregnancy toxemia in goats.

    PubMed

    González, Félix H D; Hernández, Fuensanta; Madrid, Josefa; Martínez-Subiela, Silvia; Tvarijonaviciute, Asta; Cerón, José J; Tecles, Fernando

    2011-01-01

    The present work aimed to study the behavior of acute phase proteins (haptoglobin, serum amyloid A, acid soluble glycoprotein, fibrinogen, and albumin) in fasting-induced pregnancy toxemia in goats and their relationship with classical indicators of this disorder such as beta-hydroxybutyrate and nonesterified fatty acids in the blood and decreased urine pH and ketonuria. Twelve adult Murciano-Granadina goats at the final stage of gestation were used in this experiment. Pregnancy toxemia was induced in 6 goats by fasting for 72 hr. The other 6 animals were used as control group. Ketonuria was present in 4 out of 5 fasting animals at 24 hr and in all fasting animals at 48 hr of fasting. Serum nonesterified fatty acids were significantly increased at 24, 48, and 72 hr of fasting. Beta-hydroxybutyrate and haptoglobin achieved significantly increased concentrations at 48 hr and 72 hr, respectively, remaining increased during the entire study. Serum amyloid A, acid soluble glycoprotein, fibrinogen, and albumin were not affected by fasting. In conclusion, acute phase proteins (including haptoglobin) seemed not to have an advantage over traditional markers in diagnosis of fasting-induced pregnancy toxemia in goats. PMID:21217028

  11. Dynamic hyperinflation and dyspnea during the 6-minute walk test in stable chronic obstructive pulmonary disease patients.

    PubMed

    Satake, Masahiro; Shioya, Takanobu; Uemura, Sachiko; Takahashi, Hitomi; Sugawara, Keiyu; Kasai, Chikage; Kiyokawa, Noritaka; Watanabe, Toru; Sato, Sayaka; Kawagoshi, Atsuyoshi

    2015-01-01

    The purpose of this study was to investigate the relationship between dynamic hyperinflation and dyspnea and to clarify the characteristics of dyspnea during the 6-minute walk test (6MWT) in chronic obstructive pulmonary disease patients. Twenty-three subjects with stable moderate chronic obstructive pulmonary disease (age 73.8±5.8 years, all male) took part in this study. During the 6MWT, ventilatory and gas exchange parameters were measured using a portable respiratory gas analysis system. Dyspnea and oxygen saturation were recorded at the end of every 2 minute period during the test. There was a significant decrease in inspiratory capacity during the 6MWT. This suggested that dynamic hyperinflation had occurred. Dyspnea showed a significant linear increase, and there was a significant negative correlation with inspiratory capacity. It was suggested that one of the reasons that dyspnea developed during the 6MWT was the dynamic hyperinflation. Even though the tidal volume increased little after 2 minutes, dyspnea increased linearly to the end of the 6MWT. These results suggest that the mechanisms generating dyspnea during the 6MWT were the sense of respiratory effort at an early stage and then the mismatch between central motor command output and respiratory system movement.

  12. Histochemical changes in the testes of lead induced experimental rats.

    PubMed

    Chowdhury, A R; Rao, R V; Gautam, A K

    1986-01-01

    The experiments were performed on mature male rats divided in five groups, one control and four experimental in which the animals received 1 mg, 2 mg, 4 mg and 6 mg/kg body weight lead acetate intraperitoneally respectively, over a period of 30 days. ALA-D and lead was estimated in the blood by the use of atomic absorption spectrophotometer and ATP-ase, AMP-ase, Alk-ase were histochemically localized. Significant increase in blood and testis of lead levels along with decrease of ALA-D levels were observed. Changes in the testicular tissue were encountered. Other details concerned with the damage of the testicular tissue are discussed.

  13. A 34-Year-Old Woman With Recurrent Right-Sided Chest Pain and Dyspnea.

    PubMed

    Albores, Jeffrey; Fishbein, Gregory; Bando, Joanne

    2015-11-01

    A 34-year-old woman presented with her third episode of acute-onset right-sided chest pain and dyspnea. She had two prior similar occurrences of right-sided sharp, pleuritic chest pain with radiation to the back and dyspnea. Chest radiographs during these presentations revealed a small apical right-sided pneumothorax that was managed conservatively with high-flow oxygen. All three presentations were associated with vigorous exercise and the first day of her menses. She denied cough, hemoptysis, fever, smoking history, airplane travel, scuba diving, or trauma during these presentations. The patient has been trying to conceive for the past year but has been unsuccessful because of uterine fibroids but no history of endometriosis. PMID:26527442

  14. A 34-Year-Old Woman With Recurrent Right-Sided Chest Pain and Dyspnea.

    PubMed

    Albores, Jeffrey; Fishbein, Gregory; Bando, Joanne

    2015-11-01

    A 34-year-old woman presented with her third episode of acute-onset right-sided chest pain and dyspnea. She had two prior similar occurrences of right-sided sharp, pleuritic chest pain with radiation to the back and dyspnea. Chest radiographs during these presentations revealed a small apical right-sided pneumothorax that was managed conservatively with high-flow oxygen. All three presentations were associated with vigorous exercise and the first day of her menses. She denied cough, hemoptysis, fever, smoking history, airplane travel, scuba diving, or trauma during these presentations. The patient has been trying to conceive for the past year but has been unsuccessful because of uterine fibroids but no history of endometriosis.

  15. Is there any treatment other than drugs to alleviate dyspnea in COPD patients?

    PubMed Central

    Ambrosino, Nicolino; Vagheggini, Guido

    2006-01-01

    Patients with chronic obstructive pulmonary disease (COPD) are often limited in their activities by breathlessness. In these patients, exercise training may result in significant improvements in dyspnea, exercise tolerance, and health related quality of life (HRQoL). Further possibilities are to reduce ventilatory demand by decreasing the central respiratory drive or to lessen the perceived breathing effort by increasing respiratory muscle strength through specific respiratory muscle training. Upper limb training may also improve exercise capacity and symptoms in these patients through the modulation of dynamic hyperinflation. Ventilatory assistance during exercise reduces dyspnea and work of breathing and enhances exercise tolerance, although further studies should be required to define their applicability in the routine pulmonary rehabilitation programs. Lung volume resection surgery and lung transplantation in selected patients may control symptoms and improve HRQoL. PMID:18044092

  16. 29-year-old man presenting with progressive dyspnea, oculocutaneous albinism, and epistaxis.

    PubMed

    Asefi, Golriz; Lahiji, Arta; Kamangar, Nader

    2015-06-01

    A 29-year-old man with a history of oculocutaneous albinism presented to the ED complaining of progressive dyspnea on exertion. One month prior to admission, the patient had begun to experience worsening dyspnea provoked by routine household activities. Additionally, he had developed a nonproductive cough, exacerbated by cold weather. He denied associated chest pain, hemoptysis, fever, chills, or night sweats. He denied any new exposures or sick contacts in the recent past. A review of systems was significant for a history of epistaxis and frequent bruising. Born in Honduras, he had immigrated to the United States approximately 10 years prior to his presentation to our facility. Furthermore, there was no family history of albinism, bleeding disorders, or pulmonary disease. PMID:26033137

  17. Experimental Feedback Control of Flow Induced Cavity Tones

    NASA Technical Reports Server (NTRS)

    Cabell, Randolph H.; Kegerise, Michael A.; Cox, David E.; Gibbs, Gary P.

    2005-01-01

    Discrete-time, linear quadratic methods were used to design feedback controllers for reducing tones generated by flow over a cavity. The dynamics of a synthetic jet actuator mounted at the leading edge of the cavity as observed by two microphones in the cavity were modeled over a broad frequency range using state space models computed from experimental data. Variations in closed loop performance as a function of model order, control order, control bandwidth, and state estimator design were studied using a cavity in the Probe Calibration Tunnel at NASA Langley. The controller successfully reduced the levels of multiple cavity tones at the tested flow speeds of Mach 0.275, 0.35, and 0.45. In some cases, the closed loop results were limited by excitation of sidebands of the cavity tones, or the creation of new tones at frequencies away from the cavity tones. Nonetheless, the results validate the combination of optimal control and experimentally-generated state space models, and suggest this approach may be useful for other flow control problems. The models were not able to account for non-linear dynamics, such as interactions between tones at different frequencies.

  18. Experimentally induced Fasciola hepatica infections in black-tailed deer.

    PubMed

    Kistner, T P; Koller, L D

    1975-04-01

    The susceptibility of black-tailed deer (Odocoileus hemionus columbianus) to the common liver fluke (F. hepatica) was studied. Two deer and one sheep comprised each of three experimental groups. Animals in each group were inoculated individually with 250, 500, or 1000 F. hepatica metacercariae. One deer and one sheep given 1000 metacercariae died with lesions consistent with black disease 7 weeks after inoculation. At necropsy 6 or 15 weeks postinoculation, the mean percentage recovery of the inoculum was 38.9% from the deer and 51.9% from the sheep. Fluke eggs recovered from the deer were viable and metacercariae cultured from the eggs were fully infective for sheep. Pathologic changes associated with F. hepatica infection were more severe in the infected deer; consequently, the deer were less resistant to the lethal effects of the parasite than sheep. Considering the experimental results and the fact that naturally acquired common liver fluke infection has been reported infrequently from black-tailed deer, it was concluded that black-tailed deer do not constitute a significant reservoir for F. hepatica in domestic livestock.

  19. Genistein protects dermal fibrosis in bleomycin-induced experimental scleroderma

    PubMed Central

    Koca, Süleyman Serdar; Dağlı, Adile Ferda; Yolbaş, Servet; Gözel, Nevzat; Işık, Ahmet

    2015-01-01

    Objective Genistein, a phytoestrogen, has anti-oxidant, anti-inflammatory, and anti-angiogenic properties. The aim of the present study is to evaluate the protective effect of genistein in bleomycin (BLM)-induced dermal fibrosis. Material and Methods This study involved four groups of Balb/c mice (n=10 per group). Mice in three groups were administered BLM [100 μg/day in 100 μL phosphate-buffered saline (PBS)] subcutaneously for 4 weeks; the remaining (control) group received only 100 μL/day of PBS subcutaneously. PBS or BLM was injected into the shaved upper back. Two of the BLM-treated groups also received genistein (1 or 3 mg/kg/day, subcutaneously, to the dorsal front of neck). At the end of the fourth week, all mice were sacrificed and blood and tissue samples were obtained. Results The BLM applications increased the dermal thicknesses, tissue hydroxyproline contents, α-smooth muscle actin-positive cell counts, and led to histopathologically prominent dermal fibrosis. The genistein treatments decreased the tissue hydroxyproline contents and dermal thicknesses, in the BLM-injected mice. Conclusion Genistein has antifibrotic potential in BLM-induced dermal fibrosis model. However, its therapeutic potentials on human scleroderma require evaluation in future studies.

  20. [Fetal experimentation, transplantations, cosmetics and their connection with induced abortion].

    PubMed

    Redondo Calderón, José Luis

    2012-01-01

    The increase in induced abortion produces large numbers of cells, tissues and organs, which are used in several fields of Medicine, either in research or in treatment. The main uses are in Cardiology, Hematology, Metabolism, Embryology, Neurology, Immunology, Ophthalmology, Dermatology and Transplantations. Flavor enhancers and cosmetics also benefit. Utilitarianism has led to an increase in abortion-originated cell and tissue banks. Abortion is justified through the manipulation of language. Vested interests give rise to complicity in researchers and society as a whole. Abortion and tissue 'donation' cannot be split; since fresh tissues are involved there is a symbiotic relationship between them. Valid consent is not possible. A contradiction emerges, the nasciturus is not desired or valued but fetal organs are. When someone is deprived of his rights it is because another wants to enslave them. Research must have a moral base. Knowledge should not be increased at any price. Something that is legal and well intentioned is not always morally acceptable. The duty of omission is applicable. Means to achieve a goal must be ethical means. Educational efforts to restore respect for the human embryo and fetus must be promoted. Technical advances are not always in accordance with human nature and dignity. Research and treatment that do not resort to cells, tissues and organs obtained from induced abortions should be promoted.

  1. [Fetal experimentation, transplantations, cosmetics and their connection with induced abortion].

    PubMed

    Redondo Calderón, José Luis

    2012-01-01

    The increase in induced abortion produces large numbers of cells, tissues and organs, which are used in several fields of Medicine, either in research or in treatment. The main uses are in Cardiology, Hematology, Metabolism, Embryology, Neurology, Immunology, Ophthalmology, Dermatology and Transplantations. Flavor enhancers and cosmetics also benefit. Utilitarianism has led to an increase in abortion-originated cell and tissue banks. Abortion is justified through the manipulation of language. Vested interests give rise to complicity in researchers and society as a whole. Abortion and tissue 'donation' cannot be split; since fresh tissues are involved there is a symbiotic relationship between them. Valid consent is not possible. A contradiction emerges, the nasciturus is not desired or valued but fetal organs are. When someone is deprived of his rights it is because another wants to enslave them. Research must have a moral base. Knowledge should not be increased at any price. Something that is legal and well intentioned is not always morally acceptable. The duty of omission is applicable. Means to achieve a goal must be ethical means. Educational efforts to restore respect for the human embryo and fetus must be promoted. Technical advances are not always in accordance with human nature and dignity. Research and treatment that do not resort to cells, tissues and organs obtained from induced abortions should be promoted. PMID:23320641

  2. Neuroprotective effect of melatonin in experimentally induced hypobaric hypoxia.

    PubMed

    Vornicescu, Corina; Boşca, Bianca; Crişan, Doiniţa; Yacoob, Sumaya; Stan, Nora; Filip, Adriana; Şovrea, Alina

    2013-01-01

    Melatonin (MEL) is an endogenous neurohormone with many biological functions, including a powerful antioxidant effect. The aim of the present study was to determine whether MEL protects the brain tissue from the oxidative stress induced by hypobaric hypoxia (HH) in vivo. This study was performed on Wistar rats randomly assigned in four groups, according to the pressure conditions and treatment: Group 1: normoxia and placebo; Group 2: HH and placebo; Group 3: normoxia and MEL; and Group 4: HH and MEL. The following aspects were evaluated: cognitive function (space reference and memory), oxidative stress parameters - serum and brain malondialdehyde (MDA) and reduced glutathione (GSH) levels -, and brain tissue macroscopic and microscopic morphological changes. Exposure to oxidative stress results in cognitive dysfunctions and biochemical alterations: significant increase of MDA and reduction of GSH in both serum and brain tissue. The most important morphological changes were observed in Group 2: increased cellularity, loss of pericellular haloes, shrunken neurons with scanty cytoplasm and hyperchromatic, pyknotic or absent nuclei; reactive gliosis, edema and blood-brain barrier alterations could also be observed in some areas. MEL treatment significantly diminished all these effects. Our results suggest that melatonin is a neuroprotective antioxidant both in normoxia and hypobaric hypoxia that can prevent and counteract the deleterious effects of oxidative stress (neuronal death, reactive astrogliosis, memory impairment and cognitive dysfunctions). Dietary supplements containing melatonin might be useful neuroprotective agents for the therapy of hypoxia-induced consequences. PMID:24399008

  3. Dyspnea in a case of shoulder dislocation - to beware of this rare life-threatening symptom.

    PubMed

    Joshi, Satyen Praful; Challawar, Nikhil Subhash; Agrawal, Parth Vinod; Gajjar, Arpit S

    2016-01-01

    Shoulder dislocation is a common injury in orthopedic practice. In an acute presentation, closed reduction of the shoulder joint leads to an uneventful recovery. However, in the developing world neglected shoulder dislocation and treatments from quacks are not uncommon. Improper treatment and neglect can rarely become life threatening. We present one such case, emphasizing the need to investigate the symptom of dyspnea in a patient with history of shoulder dislocation. PMID:27658507

  4. Experimental distinction of Autler-Townes splitting from electromagnetically induced transparency using coupled mechanical oscillators system

    PubMed Central

    Liu, Jingliang; Yang, Hujiang; Wang, Chuan; Xu, Kun; Xiao, Jinghua

    2016-01-01

    Here we experimentally demonstrated the electromagnetically induced transparency (EIT) and Autler-Townes splitting (ATS) effects in mechanical coupled pendulums. The analogue of EIT and ATS has been studied in mechanical systems and the intrinsic physics between these two phenomena are also been discussed. Exploiting the Akaike Information Criterion, we discern the ATS effect from EIT effect in our experimental results. PMID:26751738

  5. Experimental distinction of Autler-Townes splitting from electromagnetically induced transparency using coupled mechanical oscillators system

    NASA Astrophysics Data System (ADS)

    Liu, Jingliang; Yang, Hujiang; Wang, Chuan; Xu, Kun; Xiao, Jinghua

    2016-01-01

    Here we experimentally demonstrated the electromagnetically induced transparency (EIT) and Autler-Townes splitting (ATS) effects in mechanical coupled pendulums. The analogue of EIT and ATS has been studied in mechanical systems and the intrinsic physics between these two phenomena are also been discussed. Exploiting the Akaike Information Criterion, we discern the ATS effect from EIT effect in our experimental results.

  6. Expression of inducible nitric oxide synthase in experimental viral myocarditis.

    PubMed

    Glück, B; Merkle, I; Dornberger, G; Stelzner, A

    2000-05-01

    Nitric oxide (NO) is an important bioactive molecule with regulatory, cytotoxic or cytoprotective properties. In virus-induced myocarditis, NO mediates host defense mechanisms against the infection or causes cardiac dysfunctions. NO is synthesized from L-arginine by the enzyme nitric oxide synthase (NOS). The expression of the inducible form of the nitric oxide synthase (iNOS) is regulated by cytokines, involved in the complex myocardial immune response to enterovirus infections. The present study was undertaken to characterize the role of iNOS and NO in the murine model of viral myocarditis induced by coxsackievirus B3 (CVB3). In response to CVB3 infection we investigated the time course of iNOS induction in correlation with cytokine mRNA expression (TNF-alpha, IL-1 alpha, IFN-gamma, TGF-beta) in the heart of NMRI mice by RT-PCR. Positive PCR signals for viral RNA were found in the acute and chronic stage of disease by seminested PCR, indicating the persistence of viral genome. We found distinct expression of iNOS at all time points (1, 2, 3, 4, 7, 14, 28, 56, 98 days post infection [p.i.]). Higher iNOS mRNA levels were identified between days 4 until 28 p.i. in comparison to day 56 and 98 p.i. using densitometric values. The mRNA of the inflammatory cytokines TNF-alpha, IL-1 alpha, IFN-gamma appeared at days 1, 4, and 7 p.i., peaked at day 7 p.i. and persisted until day 98 p.i. Similar like the iNOS mRNA pattern was the expression profile of TGF-beta. Using in situ hybridization and immunohistochemistry iNOS was localized in infiltrates, vascular endothelial cells, smooth muscle cells, myocytes and throughout the interstitial spaces between myocardial fibers in the heart sections of NMRI mice. Increased levels of NO were measured as total nitrate/nitrite concentration in the sera of mice from day 7 until day 28 p.i.

  7. Histochemical changes in the testes of lead induced experimental rats.

    PubMed

    Chowdhury, A R; Rao, R V; Gautam, A K

    1986-01-01

    The experiments were performed on mature male rats divided in five groups, one control and four experimental in which the animals received 1 mg, 2 mg, 4 mg and 6 mg/kg body weight lead acetate intraperitoneally respectively, over a period of 30 days. ALA-D and lead was estimated in the blood by the use of atomic absorption spectrophotometer and ATP-ase, AMP-ase, Alk-ase were histochemically localized. Significant increase in blood and testis of lead levels along with decrease of ALA-D levels were observed. Changes in the testicular tissue were encountered. Other details concerned with the damage of the testicular tissue are discussed. PMID:3030829

  8. Dietary oregano essential oil alleviates experimentally induced coccidiosis in broilers.

    PubMed

    Mohiti-Asli, M; Ghanaatparast-Rashti, M

    2015-06-15

    An experiment was conducted to determine the effects of oregano essential oil on growth performance and coccidiosis prevention in mild challenged broilers. A total of 250 1-d-old chicks were used in a completely randomized design with 5 treatments and 5 replicates with 10 birds in each replication. Experimental treatments included: (1) negative control (NC; unchallenged), (2) positive control (PC; challenged with sporulated oocysts of Eimeria), (3) PC fed 200 ppm Diclazuril in diet, (4) PC fed 300 ppm oregano oil in diet, and (5) PC fed 500 ppm oregano oil in diet. At 22 d of age, all the experimental groups except for NC were challenged with 50-fold dose of Livacox T as a trivalent live attenuated coccidiosis vaccine. On d 28, two birds were slaughtered and intestinal coccidiosis lesions were scored 0-4. Moreover, dropping was scored in the scale of 0-3, and oocysts per gram feces (OPG) were measured. Oregano oil at either supplementation rate increased body weight gain (P=0.039) and improved feed conversion ratio (P=0.010) from d 22 to 28, when compared with PC group. Using 500 ppm oregano oil in challenged broilers diet increased European efficiency factor than PC group (P=0.020). Moreover, challenged broilers fed 500 ppm oregano oil or Diclazuril in diets displayed lower coccidiosis lesions scores in upper (P=0.003) and middle (P=0.018) regions of intestine than PC group, with the effect being similar to unchallenged birds. In general, challenged birds fed 500 ppm oregano oil or Diclazuril in diets had lower OPG (P=0.001), dropping scores (P=0.001), litter scores (P=0.001), and pH of litter (P=0.001) than PC group. It could be concluded that supplementation of oregano oil at the dose of 500 ppm in diet may have beneficial effect on prevention of coccidiosis in broilers. PMID:25864115

  9. Dietary oregano essential oil alleviates experimentally induced coccidiosis in broilers.

    PubMed

    Mohiti-Asli, M; Ghanaatparast-Rashti, M

    2015-06-15

    An experiment was conducted to determine the effects of oregano essential oil on growth performance and coccidiosis prevention in mild challenged broilers. A total of 250 1-d-old chicks were used in a completely randomized design with 5 treatments and 5 replicates with 10 birds in each replication. Experimental treatments included: (1) negative control (NC; unchallenged), (2) positive control (PC; challenged with sporulated oocysts of Eimeria), (3) PC fed 200 ppm Diclazuril in diet, (4) PC fed 300 ppm oregano oil in diet, and (5) PC fed 500 ppm oregano oil in diet. At 22 d of age, all the experimental groups except for NC were challenged with 50-fold dose of Livacox T as a trivalent live attenuated coccidiosis vaccine. On d 28, two birds were slaughtered and intestinal coccidiosis lesions were scored 0-4. Moreover, dropping was scored in the scale of 0-3, and oocysts per gram feces (OPG) were measured. Oregano oil at either supplementation rate increased body weight gain (P=0.039) and improved feed conversion ratio (P=0.010) from d 22 to 28, when compared with PC group. Using 500 ppm oregano oil in challenged broilers diet increased European efficiency factor than PC group (P=0.020). Moreover, challenged broilers fed 500 ppm oregano oil or Diclazuril in diets displayed lower coccidiosis lesions scores in upper (P=0.003) and middle (P=0.018) regions of intestine than PC group, with the effect being similar to unchallenged birds. In general, challenged birds fed 500 ppm oregano oil or Diclazuril in diets had lower OPG (P=0.001), dropping scores (P=0.001), litter scores (P=0.001), and pH of litter (P=0.001) than PC group. It could be concluded that supplementation of oregano oil at the dose of 500 ppm in diet may have beneficial effect on prevention of coccidiosis in broilers.

  10. Experimental diet-induced atherosclerosis in Quaker parrots (Myiopsitta monachus).

    PubMed

    Beaufrère, H; Nevarez, J G; Wakamatsu, N; Clubb, S; Cray, C; Tully, T N

    2013-11-01

    Spontaneous atherosclerosis is common in psittaciformes, and clinical signs associated with flow-limiting stenosis are encountered in pet birds. Nevertheless, a psittacine model of atherosclerosis has not been developed for research investigations. Sixteen captive-bred Quaker parrots (Myiopsitta monachus) were used in this study. While 4 control birds were fed a maintenance diet, 12 other birds were fed an atherogenic diet composed of 1% cholesterol controlling for a calorie-to-protein ratio for periods ranging from 2 to 8 months. The birds were euthanized at the end of their respective food trial period. Histopathology, transmission electron microscopy, and cholesterol measurement were performed on the ascending aorta and brachiocephalic and pulmonary arteries. Plasma lipoproteins, cholesterol, and triglycerides were also measured on a monthly basis. Significant atherosclerotic lesions were induced within 2 months and advanced atherosclerotic lesions within 4 to 6 months. The advanced lesions were histologically similar to naturally occurring lesions identified in the same parrot species with a lipid core and a fibrous cap. Ultrastructurally, there were extracellular lipid, foam cell, and endothelial changes. Arterial cholesterol content increased linearly over time. Plasma cholesterol and low-density lipoprotein (LDL) significantly increased over time by an average of 5- and 15-fold, respectively, with a shift from high-density lipoprotein to LDL as the main plasma lipoprotein. Quaker parrots also exhibited high plasma cholesteryl ester transfer protein activity that increased, although not significantly, over time. This experiment demonstrates that in Quaker parrots fed 1% cholesterol, advanced atherosclerosis can be induced relatively quickly, and lesions resemble those found in other avian models and humans.

  11. Experimental Studies of Laser-Induced Breakdown in Transparent Dielectrics

    SciTech Connect

    Carr, C W

    2003-09-23

    The mechanisms by which transparent dielectrics damage when exposed to high power laser radiation has been of scientific and technological interest since the invention of the laser. In this work, a set of three experiments are presented which provide insight into the damage initiation mechanisms and the processes involved in laser-induced damage. Using an OPO (optical parametric oscillator) laser, we have measured the damage thresholds of deuterated potassium dihydrogen phosphate (DKDP) from the near ultraviolet into the visible. Distinct steps, whose width is of order K{sub b}T, are observed in the damage threshold at photon energies associated with the number of photons (3{yields}2 or 4{yields}3) needed to promote a ground state electron across the energy gap. The wavelength dependence of the damage threshold suggests that a primary mechanism for damage initiation in DKDP is a multi-photon process in which the order is reduced through excited defect state absorption. In-situ fluorescence microscopy, in conjunction with theoretical calculations by Liu et al., has been used to establish that hydrogen displacement defects are potentially responsible for the reduction in the multi-photon cross-section. During the damage process, the material absorbs energy from the laser pulse and produces an ionized region that gives rise to broadband emission. By performing a time-resolved investigation of this emission, we demonstrate both that it is blackbody in nature, and we provide the first direct measurement of the localized temperature during and following laser damage initiation for various optical materials. For excitation using nanosecond laser pulses, the plasma, when confined in the bulk, is in thermal equilibrium with the lattice. These results allow for a detailed characterization of temperature, pressure, and electron densities occurring during laser-induced damage.

  12. Pulsed radio frequency therapy of experimentally induced arthritis in ponies.

    PubMed Central

    Crawford, W H; Houge, J C; Neirby, D T; Di Mino, A; Di Mino, A A

    1991-01-01

    The effect of pulsed radio frequency therapy (PRFT) was evaluated on seven ponies with no arthritis and in 28 ponies in which arthritis was created using intra-articular amphotericin B to induce synovitis in the right middle carpal joint. The ponies were divided into five treatment and two control groups. Two levels of arthritis were created and two dosage levels of PRFT were evaluated. The effect of PRFT on arthritic and nonarthritic joints was measured by comparing synovial fluid parameters, the degree and duration of lameness, the range of carpal motion, and carpus circumference, for treated and untreated groups. Lesions seen radiographically, at gross pathology, and by histopathology were also compared between the treated and control groups. In the ponies with a mild form of induced arthritis, PRFT significantly (p less than 0.05) reduced the severity and duration of lameness, swelling of the carpus, and the severity of gross pathological and radiographic changes. In these ponies the synovial acid phosphatase levels were lower, the mucin clot quality was superior, and the synovial protein levels were lower for the ponies receiving PRFT as compared to the arthritic ponies receiving no treatment. A dose response effect was evident. In ponies with a slightly more severe form of arthritis, PRFT was evaluated at one dosage level. The treated ponies were significantly improved over the untreated ponies with respect to carpal range of motion, degree of lameness, carpus swelling, and radiographic lesions. No deleterious effects were noted when normal, PRFT treated, middle carpal joints were compared to contralateral untreated, normal joints. It was concluded that significant beneficial effects resulted when affected ponies were treated with PRFT. PMID:1884288

  13. Experimental Investigation of Cavitation Induced Feedline Instability from an Orifice

    NASA Technical Reports Server (NTRS)

    Hitt, Matthew A.; Lineberry, David M.; Ahuja, Vineet; Frederick, Robert A,

    2012-01-01

    This paper details the results of an experimental investigation into the cavitation instabilities created by a circular orifice conducted at the University of Alabama in Huntsville Propulsion Research Center. This experiment was conducted in concert with a computational simulation to serve as a reference point for the simulation. Testing was conducted using liquid nitrogen as a cryogenic propellant simulant. A 1.06 cm diameter thin orifice with a rounded inlet was tested in an approximately 1.25 kg/s flow with inlet pressures ranging from 504.1 kPa to 829.3 kPa. Pressure fluctuations generated by the orifice were measured using a high frequency pressure sensor located 0.64 tube diameters downstream of the orifice. Fast Fourier Transforms were performed on the high frequency data to determine the instability frequency. Shedding resulted in a primary frequency with a cavitation related subharmonic frequency. For this experiment, the cavitation instability ranged from 153 Hz to 275 Hz. Additionally, the strength of the cavitation occur red as a function of cavitation number. At lower cavitation numbers, the strength of the cavitation instability ranged from 2.4 % to 7 % of the inlet pressure. However, at higher cavitation numbers, the strength of the cavitation instability ranged from 0.6 % to 1 % of the inlet pressure.

  14. Experimental Studies of Mitigation Materials for Blast Induced Tbi

    NASA Astrophysics Data System (ADS)

    Alley, M. D.; Son, S. F.; Christou, G.; Goel, R.; Young, L.

    2009-12-01

    The objective of this experimental study is to compare the effects of various materials obstructing the flow of a blast wave and the ability of the material to reduce the damage caused by the blast. Several methods of energy transfer in blast wave flows are expected including: material interfaces with impedance mismatches, density changes in a given material, internal shearing, and particle fracture. Our hypothesis is that the greatest energy transfer within the obstructing material will yield the greatest mitigation effects to the blast. Sample configurations of foam were varied to introduce material interfaces and filler materials with varying densities and impedances (liquids and powders). The samples were dynamically loaded using a small scale blast produced by an explosive driven shock tube housing gram-scale explosive charges. The transmitted blast profiles were analyzed for variations in impulse characteristics and frequency components as compared to standard free field profiles. The results showed a rounding effect of the transmitted blast profile for all samples with the effects of the high density fillers surpassing all others tested. These results lead to a conclusion that low porosity, high density materials offer superior attenuation by reducing air blast features and spatially distributing the transmitted wave.

  15. Experimental Studies of Mitigation Materials for Blast Induced TBI

    NASA Astrophysics Data System (ADS)

    Alley, Matthew; Son, Steven

    2009-06-01

    The objective of this experimental study is to compare the effects of various materials obstructing the flow of a blast wave and the ability of the given material to reduce the damage caused by the blast. Several methods of energy transfer in blast wave flows are known or expected including: material interfaces with impedance mismatches, density changes in a given material, internal shearing, and particle fracture. The theory applied to this research is that the greatest energy transfer within the obstructing material will yield the greatest mitigation effects to the blast. Sample configurations of foam were varied to introduce material interfaces and filler materials with varying densities and impedances (liquids and powders). The samples were loaded according to a small scale blast produced by an explosive driven shock tube housing gram-range charges. The transmitted blast profiles were analyzed for variations in impulse characteristics and frequency components as compared to standard free field profiles. The results showed a rounding effect of the transmitted blast profile for all samples with the effects of the low density fillers surpassing all others tested.

  16. Toxin-Induced Experimental Models of Learning and Memory Impairment

    PubMed Central

    More, Sandeep Vasant; Kumar, Hemant; Cho, Duk-Yeon; Yun, Yo-Sep; Choi, Dong-Kug

    2016-01-01

    Animal models for learning and memory have significantly contributed to novel strategies for drug development and hence are an imperative part in the assessment of therapeutics. Learning and memory involve different stages including acquisition, consolidation, and retrieval and each stage can be characterized using specific toxin. Recent studies have postulated the molecular basis of these processes and have also demonstrated many signaling molecules that are involved in several stages of memory. Most insights into learning and memory impairment and to develop a novel compound stems from the investigations performed in experimental models, especially those produced by neurotoxins models. Several toxins have been utilized based on their mechanism of action for learning and memory impairment such as scopolamine, streptozotocin, quinolinic acid, and domoic acid. Further, some toxins like 6-hydroxy dopamine (6-OHDA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and amyloid-β are known to cause specific learning and memory impairment which imitate the disease pathology of Parkinson’s disease dementia and Alzheimer’s disease dementia. Apart from these toxins, several other toxins come under a miscellaneous category like an environmental pollutant, snake venoms, botulinum, and lipopolysaccharide. This review will focus on the various classes of neurotoxin models for learning and memory impairment with their specific mechanism of action that could assist the process of drug discovery and development for dementia and cognitive disorders. PMID:27598124

  17. Toxin-Induced Experimental Models of Learning and Memory Impairment.

    PubMed

    More, Sandeep Vasant; Kumar, Hemant; Cho, Duk-Yeon; Yun, Yo-Sep; Choi, Dong-Kug

    2016-01-01

    Animal models for learning and memory have significantly contributed to novel strategies for drug development and hence are an imperative part in the assessment of therapeutics. Learning and memory involve different stages including acquisition, consolidation, and retrieval and each stage can be characterized using specific toxin. Recent studies have postulated the molecular basis of these processes and have also demonstrated many signaling molecules that are involved in several stages of memory. Most insights into learning and memory impairment and to develop a novel compound stems from the investigations performed in experimental models, especially those produced by neurotoxins models. Several toxins have been utilized based on their mechanism of action for learning and memory impairment such as scopolamine, streptozotocin, quinolinic acid, and domoic acid. Further, some toxins like 6-hydroxy dopamine (6-OHDA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and amyloid-β are known to cause specific learning and memory impairment which imitate the disease pathology of Parkinson's disease dementia and Alzheimer's disease dementia. Apart from these toxins, several other toxins come under a miscellaneous category like an environmental pollutant, snake venoms, botulinum, and lipopolysaccharide. This review will focus on the various classes of neurotoxin models for learning and memory impairment with their specific mechanism of action that could assist the process of drug discovery and development for dementia and cognitive disorders. PMID:27598124

  18. Enhanced bile formation induced by experimental dicrocoeliosis in the hamster.

    PubMed

    Sánchez-Campos, S; Tuñón, M J; González, P; Marín, J J; González-Gallego, J

    1998-01-01

    The purpose of this investigation was to determine the effects of experimental dicrocoeliosis on bile formation in the hamster. Studies were carried out at 120 days after infection with an oral dose of 40 metacercariae of Dicrocoelium dendriticum. A significant elevation in bile flow (+20%) and in the biliary output of glutathione (+34%), bile acid (+59%), cholesterol (+108%), phospholipids (+99%) and alkaline phosphatase (+36%) was observed in the infected animals. The bile-to-plasma [14C] mannitol ratio increased to values greater than 1 and there was a reduced contribution (-26%) of biliary tree to bile formation. Those data suggest that enhancement in choleresis had a canalicular origin. The presence of oxidative stress, evidenced by the increased oxidized/reduced glutathione ratio and TBARS concentrations, may contribute to the elevated glutathione efflux into bile. Enhancement in bile acid output was not due to qualitative or quantitative changes in bile acid metabolism, as indicated by the absence of significant modification in liver cholesterol 7alpha-hydroxylase activity and bile acid profile in bile. Increase in the ability of the canalicular membrane to export bile acids was not involved, since maximal secretion rate for exogenously administered taurocholate was decreased. When bile flow, bile acid and biliary lipid secretion was determined in colchicine-pretreated animals differences between control and infected animals were abolished, suggesting that stimulation of the transcytotic vesicle pathway plays an important role in the alteration of the biliary function caused by dicrocoeliosis.

  19. Experimentally induced metamorphosis in axolotls reduces regenerative rate and fidelity

    PubMed Central

    Stier, Adrian C.; Michonneau, François; Smith, Matthew D.; Pasch, Bret; Maden, Malcolm

    2014-01-01

    Abstract While most tetrapods are unable to regenerate severed body parts, amphibians display a remarkable ability to regenerate an array of structures. Frogs can regenerate appendages as larva, but they lose this ability around metamorphosis. In contrast, salamanders regenerate appendages as larva, juveniles, and adults. However, the extent to which fundamental traits (e.g., metamorphosis, body size, aging, etc.) restrict regenerative ability remains contentious. Here we utilize the ability of normally paedomorphic adult axolotls (Ambystoma mexicanum) to undergo induced metamorphosis by thyroxine exposure to test how metamorphosis and body size affects regeneration in age‐matched paedomorphic and metamorphic individuals. We show that body size does not affect regeneration in adult axolotls, but metamorphosis causes a twofold reduction in regeneration rate, and lead to carpal and digit malformations. Furthermore, we find evidence that metamorphic blastemal cells may take longer to traverse the cell cycle and display a lower proliferative rate. This study identifies the axolotl as a powerful system to study how metamorphosis restricts regeneration independently of developmental stage, body size, and age; and more broadly how metamorphosis affects tissue‐specific changes. PMID:27499857

  20. Experimental rabies in skunks: effects of immunosuppression induced by cyclophosphamide.

    PubMed

    Charlton, K M; Casey, G A; Campbell, J B

    1984-01-01

    Striped skunks (Mephitis mephitis) were inoculated with street rabies virus and immunosuppressed with several doses of cyclophosphamide. Control skunks were inoculated with street virus only. The skunks were killed in terminal stages of the disease and several tissues were collected for examination by immunofluorescence, light microscopy and viral titration. Sera collected at euthanasia from most of the principals did not contain detectable rabies neutralizing antibodies, whereas high titers occurred terminally in controls. Immunofluorescence was much more entensive in submandibular salivary glands of cyclophosphamide-treated than control skunks. Similarly, virus was isolated from this tissue more consistently and at higher titer from principals than from controls. Immunofluorescence was extensive in brains of all skunks (both groups), but virus was isolated consistently only from brains of cyclophosphamide-treated skunks. Most of the cyclophosphamide-treated skunks had very few inflammatory cells in brain and cerebrospinal ganglia. Neuronal degeneration occurred in dorsal root ganglia of both principals and controls. The results suggest that the immune response has no effect on the development of rabies-induced aggressive behavior, that the immune response may inhibit salivary gland infection and that it is not essential for the development of neuronal degeneration in dorsal root ganglia.

  1. Experimental and theoretical investigations on shock wave induced phase transitions

    NASA Astrophysics Data System (ADS)

    Gupta, Satish C.; Sikka, S. K.

    2001-06-01

    Shock wave loading of a material can cause variety of phase transitions, like polymorphism, amorphization, metallization and molecular dissociations. As the shocked state lasts only for a very short duration (about a few microseconds or less), in-situ microscopic measurements are very difficult. Although such studies are beginning to be possible, most of the shock-induced phase transitions are detected using macroscopic measurements. The microscopic nature of the transition is then inferred from comparison with static pressure data or interpreted by theoretical methods. For irreversible phase transitions, microscopic measurements on recovered samples, together with orientation relations determined from selected area electron diffraction and examination of the morphology of growth of the new phase can provide insight into mechanism of phase transitions. On theoretical side, the current ab initio band structure techniques based on density functional formalism provide capability for accurate computation of the small energy differences (a few mRy or smaller) between different plausible structures. Total energy calculation along the path of a phase transition can furnish estimates of activation barrier, which has implications for understanding kinetics of phase transitions. Molecular dynamics calculations, where the new structure evolves naturally, are becoming increasingly popular especially for understanding crystal to amorphous phase transitions. Illustrations from work at our laboratory will be presented.

  2. Experimental treatment of antipsychotic-induced movement disorders

    PubMed Central

    Shireen, Erum

    2016-01-01

    Antipsychotic drugs are extensively prescribed for the treatment of schizophrenia and other related psychiatric disorders. These drugs produced their action by blocking dopamine (DA) receptors, and these receptors are widely present throughout the brain. Therefore, extended antipsychotic use also leads to severe extrapyramidal side effects. The short-term effects include parkinsonism and the later appearing tardive dyskinesia. Currently available treatments for these disorders are mostly symptomatic and insufficient, and are often linked with a number of detrimental side effects. Antipsychotic-drug-induced tardive dyskinesia prompted researchers to explore novel drugs with fewer undesirable extrapyramidal side effects. Preclinical studies suggest a role of 5-hydroxytryptamine (serotonin)-1A and 2A/2C receptors in the modulation of dopaminergic neurotransmission and motivating a search for better therapeutic strategies for schizophrenia and related disorders. In addition, adjunctive treatment with antioxidants such as vitamin E, red rice bran oil, and curcumin in the early phases of illness may prevent additional oxidative injury, and thus improve and prevent further possible worsening of related neurological and behavioral deficits in schizophrenia. This review explains the role of serotonergic receptors and oxidative stress, with the aim of providing principles for prospect development of compounds to improve therapeutic effects of antischizophrenic drugs. PMID:27540314

  3. Experimental treatment of antipsychotic-induced movement disorders.

    PubMed

    Shireen, Erum

    2016-01-01

    Antipsychotic drugs are extensively prescribed for the treatment of schizophrenia and other related psychiatric disorders. These drugs produced their action by blocking dopamine (DA) receptors, and these receptors are widely present throughout the brain. Therefore, extended antipsychotic use also leads to severe extrapyramidal side effects. The short-term effects include parkinsonism and the later appearing tardive dyskinesia. Currently available treatments for these disorders are mostly symptomatic and insufficient, and are often linked with a number of detrimental side effects. Antipsychotic-drug-induced tardive dyskinesia prompted researchers to explore novel drugs with fewer undesirable extrapyramidal side effects. Preclinical studies suggest a role of 5-hydroxytryptamine (serotonin)-1A and 2A/2C receptors in the modulation of dopaminergic neurotransmission and motivating a search for better therapeutic strategies for schizophrenia and related disorders. In addition, adjunctive treatment with antioxidants such as vitamin E, red rice bran oil, and curcumin in the early phases of illness may prevent additional oxidative injury, and thus improve and prevent further possible worsening of related neurological and behavioral deficits in schizophrenia. This review explains the role of serotonergic receptors and oxidative stress, with the aim of providing principles for prospect development of compounds to improve therapeutic effects of antischizophrenic drugs. PMID:27540314

  4. Experimentally induced metamorphosis in axolotls reduces regenerative rate and fidelity.

    PubMed

    Monaghan, James R; Stier, Adrian C; Michonneau, François; Smith, Matthew D; Pasch, Bret; Maden, Malcolm; Seifert, Ashley W

    2014-02-01

    While most tetrapods are unable to regenerate severed body parts, amphibians display a remarkable ability to regenerate an array of structures. Frogs can regenerate appendages as larva, but they lose this ability around metamorphosis. In contrast, salamanders regenerate appendages as larva, juveniles, and adults. However, the extent to which fundamental traits (e.g., metamorphosis, body size, aging, etc.) restrict regenerative ability remains contentious. Here we utilize the ability of normally paedomorphic adult axolotls (Ambystoma mexicanum) to undergo induced metamorphosis by thyroxine exposure to test how metamorphosis and body size affects regeneration in age-matched paedomorphic and metamorphic individuals. We show that body size does not affect regeneration in adult axolotls, but metamorphosis causes a twofold reduction in regeneration rate, and lead to carpal and digit malformations. Furthermore, we find evidence that metamorphic blastemal cells may take longer to traverse the cell cycle and display a lower proliferative rate. This study identifies the axolotl as a powerful system to study how metamorphosis restricts regeneration independently of developmental stage, body size, and age; and more broadly how metamorphosis affects tissue-specific changes. PMID:27499857

  5. Chemically induced skin carcinogenesis: Updates in experimental models (Review)

    PubMed Central

    NEAGU, MONICA; CARUNTU, CONSTANTIN; CONSTANTIN, CAROLINA; BODA, DANIEL; ZURAC, SABINA; SPANDIDOS, DEMETRIOS A.; TSATSAKIS, ARISTIDIS M.

    2016-01-01

    Skin cancer is one of the most common malignancies affecting humans worldwide, and its incidence is rapidly increasing. The study of skin carcinogenesis is of major interest for both scientific research and clinical practice and the use of in vivo systems may facilitate the investigation of early alterations in the skin and of the mechanisms involved, and may also lead to the development of novel therapeutic strategies for skin cancer. This review outlines several aspects regarding the skin toxicity testing domain in mouse models of chemically induced skin carcinogenesis. There are important strain differences in view of the histological type, development and clinical evolution of the skin tumor, differences reported decades ago and confirmed by our hands-on experience. Using mouse models in preclinical testing is important due to the fact that, at the molecular level, common mechanisms with human cutaneous tumorigenesis are depicted. These animal models resemble human skin cancer development, in that genetic changes caused by carcinogens and pro-inflammatory cytokines, and simultaneous inflammation sustained by pro-inflammatory cytokines and chemokines favor tumor progression. Drugs and environmental conditions can be tested using these animal models. keeping in mind the differences between human and rodent skin physiology. PMID:26986013

  6. Photodynamic therapy induced vascular damage: an overview of experimental PDT

    NASA Astrophysics Data System (ADS)

    Wang, W.; Moriyama, L. T.; Bagnato, V. S.

    2013-02-01

    Photodynamic therapy (PDT) has been developed as one of the most important therapeutic options in the treatment of cancer and other diseases. By resorting to the photosensitizer and light, which convert oxygen into cytotoxic reactive oxygen species (ROS), PDT will induce vascular damage and direct tumor cell killing. Another consequence of PDT is the microvascular stasis, which results in hypoxia and further produces tumor regression. To improve the treatment with PDT, three promising strategies are currently attracting much interest: (1) the combination of PDT and anti-angiogenesis agents, which more effectively prevent the proliferation of endothelial cells and the formation of new blood vessels; (2) the nanoparticle-assisted delivery of photosensitizer, which makes the photosensitizer more localized in tumor sites and thus renders minimal damage to the normal tissues; (3) the application of intravascular PDT, which can avoid the loss of energy during the transmission and expose the target area directly. Here we aim to review the important findings on vascular damage by PDT on mice. The combination of PDT with other approaches as well as its effect on cancer photomedicine are also reviewed.

  7. Experimental particle acceleration by water evaporation induced by shock waves

    NASA Astrophysics Data System (ADS)

    Scolamacchia, T.; Alatorre Ibarguengoitia, M.; Scheu, B.; Dingwell, D. B.; Cimarelli, C.

    2010-12-01

    Shock waves are commonly generated during volcanic eruptions. They induce sudden changes in pressure and temperature causing phase changes. Nevertheless, their effects on flowfield properties are not well understood. Here we investigate the role of gas expansion generated by shock wave propagation in the acceleration of ash particles. We used a shock tube facility consisting of a high-pressure (HP) steel autoclave (450 mm long, 28 mm in internal diameter), pressurized with Ar gas, and a low-pressure tank at atmospheric conditions (LP). A copper diaphragm separated the HP autoclave from a 180 mm tube (PVC or acrylic glass) at ambient P, with the same internal diameter of the HP reservoir. Around the tube, a 30 cm-high acrylic glass cylinder, with the same section of the LP tank (40 cm), allowed the observation of the processes occurring downstream from the nozzle throat, and was large enough to act as an unconfined volume in which the initial diffracting shock and gas jet expand. All experiments were performed at Pres/Pamb ratios of 150:1. Two ambient conditions were used: dry air and air saturated with steam. Carbon fibers and glass spheres in a size range between 150 and 210 μm, were placed on a metal wire at the exit of the PVC tube. The sudden decompression of the Ar gas, due to the failure of the diaphragm, generated an initial air shock wave. A high-speed camera recorded the processes between the first 100 μsec and several ms after the diaphragm failure at frame rates ranging between 30,000 and 50,000 fps. In the experiments with ambient air saturated with steam, the high-speed camera allowed to visualize the condensation front associated with the initial air shock; a maximum velocity of 788 m/s was recorded, which decreases to 524 m/s at distance of 0.5 ±0.2 cm, 1.1 ms after the diaphragm rupture. The condensation front preceded the Ar jet front exhausting from the reservoir, by 0.2-0.5 ms. In all experiments particles velocities following the initial

  8. Experimental systems for mechanistic studies of toxicant induced lung inflammation.

    PubMed

    Wallaert, B; Fahy, O; Tsicopoulos, A; Gosset, P; Tonnel, A B

    2000-03-15

    Human breath contains a large array of complex and poorly characterized mixtures. We can measure the potential risk of these exposures at molecular, cell, organ, organismic levels or in population. This paper emphasizes the characteristics of in vitro tests of lung cells and discusses the use of in vitro systems to determine the health effects of inhaled pollutants. Exposure to gases can be performed with roller bottles fitted with modified rotating caps with tubing connections, or by using dishes on rocker platforms, which tilt back and forth to expose the cell culture to gases. Exposure of cells may also be obtained by using very thin gas-permable membrane on which cells grow. However, it is clear that in using these systems, the culture medium constitutes a barrier between the gas and the target cells and thus does not permit a physiological approach of the toxic effects of gases. This is the reason why an experimental model, using a biphasic cell culture technique in gas phase, was developed. We report the value and the limits of this method using bronchial cells or alveolar macrophages. Exposure of lung cells to gas pollutants or particles may be responsible for either cell injury or cell activation associated with the overexpression of mRNA and the release of various bioactive mediators. In vitro assays have some limitations, particularly because the human pulmonary response to inhaled pollutants is the result of complex interactions involving many different cell types within the lungs. However, cell culture using biphasic systems in aerobiosis opens new ways for the research on the biological effects of gas pollutants.

  9. Experimental investigation of the flow induced by artificial cilia.

    PubMed

    Hussong, J; Schorr, N; Belardi, J; Prucker, O; Rühe, J; Westerweel, J

    2011-06-21

    The fluid transport produced by rectangular shaped, magnetically actuated artificial cilia of 70 μm length and 20 μm width was determined by means of phase-locked Micro Particle Image Velocimetry (μPIV) measurements in a closed microfluidic chamber. The phase-averaged flow produced by the artificial cilia reached up to 130 μm s(-1) with an actuation cycle frequency of 10 Hz. Analysis of the measured flow data indicate that the present system is capable of achieving volume flow rates of V[combining dot above](cilia) = 14 ± 4 μl min(-1) in a micro channel of 0.5 × 5 mm(2) cross-sectional area when no back pressure is built up. This corresponds to an effective pressure gradient of 6 ± 1 Pa m(-1), which equals a pressure difference of 0.6 ± 0.1 mPa over a distance of 100 μm between two rows of cilia. These results were derived analytically from the measured velocity profile by treating the cilia as a thin boundary layer. While the cilia produce phase-averaged velocities of the order of O(10(2)μm s(-1)), time-resolved measurements showed that the flow field reverses two times during one actuation cycle inducing instantaneous velocities of up to approximately 2 mm s(-1). This shows that the flow field is dominated by fluid oscillations and flow rates are expected to increase if the beating motion of the cilia is further improved. PMID:21614349

  10. Predictions of Experimentally Observed Stochastic Ground Vibrations Induced by Blasting

    PubMed Central

    Kostić, Srđan; Perc, Matjaž; Vasović, Nebojša; Trajković, Slobodan

    2013-01-01

    In the present paper, we investigate the blast induced ground motion recorded at the limestone quarry “Suva Vrela” near Kosjerić, which is located in the western part of Serbia. We examine the recorded signals by means of surrogate data methods and a determinism test, in order to determine whether the recorded ground velocity is stochastic or deterministic in nature. Longitudinal, transversal and the vertical ground motion component are analyzed at three monitoring points that are located at different distances from the blasting source. The analysis reveals that the recordings belong to a class of stationary linear stochastic processes with Gaussian inputs, which could be distorted by a monotonic, instantaneous, time-independent nonlinear function. Low determinism factors obtained with the determinism test further confirm the stochastic nature of the recordings. Guided by the outcome of time series analysis, we propose an improved prediction model for the peak particle velocity based on a neural network. We show that, while conventional predictors fail to provide acceptable prediction accuracy, the neural network model with four main blast parameters as input, namely total charge, maximum charge per delay, distance from the blasting source to the measuring point, and hole depth, delivers significantly more accurate predictions that may be applicable on site. We also perform a sensitivity analysis, which reveals that the distance from the blasting source has the strongest influence on the final value of the peak particle velocity. This is in full agreement with previous observations and theory, thus additionally validating our methodology and main conclusions. PMID:24358140

  11. Plant-induced weathering of a basaltic rock: experimental evidence

    NASA Astrophysics Data System (ADS)

    Hinsinger, Philippe; Fernandes Barros, Omar Neto; Benedetti, Marc F.; Noack, Yves; Callot, Gabriel

    2001-01-01

    The active role of higher plants in the weathering of silicate minerals and rocks is still a question for debate. The present work aimed at providing experimental evidence of the important role of a range of crop plants in such processes. In order to quantitatively assess the possible effect of these diverse plant species on the weathering of a basaltic rock, two laboratory experiments were carried out at room temperature. These compared the amounts of elements released from basalt when leached with a dilute salt solution in the presence or absence of crop plants grown for up to 36 days. For Si, Ca, Mg, and Na, plants resulted in an increase in the release rate by a factor ranging from 1 to 5 in most cases. Ca and Na seemed to be preferentially released relative to other elements, suggesting that plagioclase dissolved faster than the other constituents of the studied basalt. Negligible amounts of Fe were released in the absence of plants as a consequence of the neutral pH and atmospheric pO 2 that were maintained in the leaching solution. However, the amounts of Fe released from basalt in the presence of plants were up to 100- to 500-fold larger than in the absence of plants, for banana and maize. The kinetics of dissolution of basalt in the absence of plants showed a constantly decreasing release rate over the whole duration of the experiment (36 days). No steady state value was reached both in the absence and presence of banana plants. However, in the latter case, the rates remained at a high initial level over a longer period of time (up to 15 days) before starting to decrease. For Fe, the maximum rate of release was reached beyond 4 days and this rate remained high up to 22 days of growth of banana. The possible mechanisms responsible for this enhanced release of elements from basalt in the presence of plants are discussed. Although these mechanisms need to be elucidated, the present results clearly show that higher plants can considerably affect the kinetics

  12. Experimental demonstration of population inversion driven by retroreflection-induced bichromatic adiabatic passage

    SciTech Connect

    Conde, Alvaro Peralta; Yatsenko, Leonid P.; Klein, Jens; Oberst, Martin; Halfmann, Thomas

    2005-11-15

    We present experimental data to demonstrate coherently driven population inversion by retroreflection-induced bichromatic adiabatic passage in metastable helium atoms. Complete and robust population transfer from an initial to a target state is induced by coherent interaction of the atoms in a supersonic beam with two counterpropagating and temporally delayed laser pulses of different intensities. The radiation fields intersect the atomic beam slightly tilted away from normal incidence, thereby inducing Doppler shifts of the atomic resonance between the initial and the target state. Thus the laser pulses produce a bichromatic field in the rest frame of each atom, which induces complete coherent population transfer by an adiabatic passage process.

  13. Experimental gastric ulcers induced by immobilization and electric shock of rats and their pharmacotherapy

    NASA Technical Reports Server (NTRS)

    Zabrodin, O. N.

    1980-01-01

    The mechanism of development of experimental gastric ulcers, induced in rats by combined immobilization and electric shock, was analyzed pharmacologically with peripheral neurotropic agents. It is concluded that: (1) The most marked preventive effect in the development of the experimentally induced gastric ulcers was displayed by agents capable of blocking the ascending activation system of the reticular formation. (2) Sympathetic fibers, which disrupt the trophism of the gastric wall, form the efferent portion of the reflex arc. (3) Gastric secretion does not appear to be the primary cause of ulceration.

  14. Colloid-induced kidney injury: experimental evidence may help to understand mechanisms.

    PubMed

    Schortgen, Frédérique; Brochard, Laurent

    2009-01-01

    Fluid resuscitation is widely used, and many patients are therefore exposed to plasma volume expanders. Among these, colloids, particularly hydroxyethyl starches, have been shown in recent experiments and clinical studies to induce acute kidney injury. The mechanisms of colloid-induced acute kidney injury remain incompletely elucidated. The risks associated with colloid osmotic pressure elevation in vivo and the high incidence of osmotic nephrosis lesions in experimental models and clinical studies indicate that hydroxyethyl starches can no longer be considered safe.

  15. Platypnea–Orthodeoxia Syndrome: Multiple Pathophysiological Interpretations of a Clinical Picture Primarily Consisting of Orthostatic Dyspnea

    PubMed Central

    De Vecchis, Renato; Baldi, Cesare; Ariano, Carmelina

    2016-01-01

    Platypnea–orthodexia syndrome (POS) is often a challenging diagnostic problem. It is characterized by dyspnea that is accentuated by standing or sitting positions due to a marked fall in blood oxygen saturation, and instead is improved by assuming the lying position. In the present brief review, the authors address the pathophysiology of POS, and outline its clinical symptoms as well as the main modalities of diagnostic evaluation and possible therapeutic options. Moreover, some problems concerning much-debated issues and persistent uncertainties about the pathophysiology of POS are presented along with the description of the diagnostic and therapeutic resources currently available for this syndrome. PMID:27669319

  16. An uncommon case of dyspnea with unilateral laryngeal paralysis in acromegaly.

    PubMed

    Lerat, Justine; Lacoste, Marie; Prechoux, Jean-Marc; Aubry, Karine; Nadalon, Sylvie; Ly, Kim Heang; Bessede, Jean-Pierre

    2016-02-01

    A 61-year-old man with obstructive sleep apnea syndrome and normal BMI complained of dyspnea. Nasofibroscopy revealed a global and major oedema of the glottis and supraglottis and also a paralysis of the left vocal fold. CT-scan pointed out a spontaneous hyperdensity of the left arytenoid cartilage. A tracheostomy was performed. Clinical examination revealed large hands and macroglossy with high IGF1 rate. MRI confirmed a supracentimetric pituitary adenoma. To our knowledge, this is the first description of a case of acute respiratory distress due to unilateral larynx paralysis leading to acromegaly diagnosis. This is due to submucosal hypertrophy and vocal cord immobility.

  17. Platypnea-Orthodeoxia Syndrome: Multiple Pathophysiological Interpretations of a Clinical Picture Primarily Consisting of Orthostatic Dyspnea.

    PubMed

    De Vecchis, Renato; Baldi, Cesare; Ariano, Carmelina

    2016-01-01

    Platypnea-orthodexia syndrome (POS) is often a challenging diagnostic problem. It is characterized by dyspnea that is accentuated by standing or sitting positions due to a marked fall in blood oxygen saturation, and instead is improved by assuming the lying position. In the present brief review, the authors address the pathophysiology of POS, and outline its clinical symptoms as well as the main modalities of diagnostic evaluation and possible therapeutic options. Moreover, some problems concerning much-debated issues and persistent uncertainties about the pathophysiology of POS are presented along with the description of the diagnostic and therapeutic resources currently available for this syndrome. PMID:27669319

  18. An uncommon case of dyspnea with unilateral laryngeal paralysis in acromegaly.

    PubMed

    Lerat, Justine; Lacoste, Marie; Prechoux, Jean-Marc; Aubry, Karine; Nadalon, Sylvie; Ly, Kim Heang; Bessede, Jean-Pierre

    2016-02-01

    A 61-year-old man with obstructive sleep apnea syndrome and normal BMI complained of dyspnea. Nasofibroscopy revealed a global and major oedema of the glottis and supraglottis and also a paralysis of the left vocal fold. CT-scan pointed out a spontaneous hyperdensity of the left arytenoid cartilage. A tracheostomy was performed. Clinical examination revealed large hands and macroglossy with high IGF1 rate. MRI confirmed a supracentimetric pituitary adenoma. To our knowledge, this is the first description of a case of acute respiratory distress due to unilateral larynx paralysis leading to acromegaly diagnosis. This is due to submucosal hypertrophy and vocal cord immobility. PMID:26142980

  19. Progressive Dyspnea in a 40-Year-Old Man Caused by Giant Mediastinal Thymolipoma

    PubMed Central

    Rad, Kamelia

    2016-01-01

    Thymolipomas are rare tumors of the anterior mediastinum containing both thymic stroma and an abundance of fat. We present a 40-year-old man with no underlying disease who presented with cough and progressive dyspnea. Clinical evaluation revealed a giant mass of lipid density filling almost the entire left hemithorax with mediastinal shift. Total excision of the 40 × 33 × 8 cm mass weighing 4 kg was performed via a left thoracotomy and the histopathologic diagnosis of the mass was reported as thymolipoma. The patient remains alive and disease-free, twelve months after the intervention. PMID:27293949

  20. Noninvasive Tests for the Diagnostic Evaluation of Dyspnea Among Outpatients: the Multi-Ethnic Study of Atherosclerosis Lung Study

    PubMed Central

    Oelsner, Elizabeth C; Lima, Joao AC; Kawut, Steven M; Burkart, Kristin M; Enright, Paul L; Ahmed, Firas S; Barr, R Graham

    2015-01-01

    Background Dyspnea on exertion is a common and debilitating complaint, yet evidence for the relative value of cardiac and pulmonary tests for the evaluation of chronic dyspnea among adults without known cardiac or pulmonary disease is limited. Methods The Multi-Ethnic Study of Atherosclerosis (MESA) enrolled participants ages 45-84 years who were free of clinical cardiovascular disease from six communities; participants with clinical pulmonary disease were excluded from this report. Dyspnea on exertion was assessed via structured interview. Tests included electrocardiograms, cardiac computed tomography (CT) for coronary artery calcium, cardiac magnetic resonance imaging, spirometry, percent emphysema (percent of lung regions < -950 Hounsfield Units) on CT, inflammatory biomarkers and N-terminal pro-Brain Natriuretic Peptide (NT-proBNP). Logistic regression was used to identify independent correlates of dyspnea after adjustment for age, sex, body mass index, physical activity, anxiety, and leg pain. Results Among 1,969 participants without known cardiopulmonary disease, 9% had dyspnea. The forced expiratory volume in one second (FEV1) (p <0.001), NT-proBNP (p=0.004), and percent emphysema on CT (p=0.004) provided independent information on the probability of self-reported dyspnea. Associations with the FEV1 were stronger among smokers and participants with other recent respiratory symptoms or seasonal allergies; associations with NT-proBNP were present only among participants with coexisting symptoms of lower extremity edema. Only the FEV1 provided a significant improvement in the receiver operating curve. Conclusions Among adults without known cardiac or pulmonary disease reporting dyspnea on exertion, spirometry, NT-proBNP, and CT imaging for pulmonary parenchymal disease were the most informative tests. PMID:25447621

  1. Experimental coronary sclerosis induced by immobilization of rabbits: A new model of arteriosclerosis

    NASA Technical Reports Server (NTRS)

    Tyavokin, V. V.; Tjawokin, W. W.

    1980-01-01

    A new method for producing arteriosclerosis with coronary insufficiency in rabbits by means of immobilization is described and discussed. The experimentally induced atherosclerosis develops due to hypodynamics imposed by the reduced muscular activity without overloading with exogenous cholesterol. The atherosclerosis and coronary insufficiency are associated. With variations in the duration and extent of immobilization, coronary insufficiency alone or with atherosclerosis can be produced.

  2. Effect of Nebulized Morphine on Dyspnea of Mustard Gas-Exposed Patients: A Double-Blind Randomized Clinical Trial Study

    PubMed Central

    Shohrati, Majid; Ghanei, Mostafa; Harandi, Asghar Amini; Foroghi, Soniya; Harandi, Ali Amini

    2012-01-01

    Background. Dyspnea is one of the main complaints in a group of COPD patients due to exposure to sulfur mustard (SM) and is refractory to conventional therapies. We designed this study to evaluate effectiveness of nebulized morphine in such patients. Materials and Methods. In a double-blind clinical trial study, 40 patients with documented history of exposure to SM were allocated to two groups: group 1 who received 1 mg morphine sulfate diluted by 4 cc normal saline 0.5% using nebulizer once daily for 5 days and group 2 serving as control who received normal saline as placebo. They were visited by pulmonologist 7 times per day to check symptoms and signs and adverse events. Different parameters including patient-scored peak expiratory flow using pick flow meter, visual analogue scale (VAS) for dyspnea, global quality of life and cough, and number of respiratory rate, night time awaking for dyspnea and cough have been assessed. Results. The scores of VAS for dyspnea, cough and quality of life and also respiratory rate, heart rate, and night time awaking due to dyspnea and night time awaking due to cough improved significantly after morphine nebulization without any major adverse events. Also pick expiratory flow has been improved significantly after nebulization in each day. Conclusion. Our results showed the clinical benefit of nebulized morphine on respiratory complaints of patients due to exposure to SM without significant side effects. PMID:22530119

  3. Effect of nebulized morphine on dyspnea of mustard gas-exposed patients: a double-blind randomized clinical trial study.

    PubMed

    Shohrati, Majid; Ghanei, Mostafa; Harandi, Asghar Amini; Foroghi, Soniya; Harandi, Ali Amini

    2012-01-01

    Background. Dyspnea is one of the main complaints in a group of COPD patients due to exposure to sulfur mustard (SM) and is refractory to conventional therapies. We designed this study to evaluate effectiveness of nebulized morphine in such patients. Materials and Methods. In a double-blind clinical trial study, 40 patients with documented history of exposure to SM were allocated to two groups: group 1 who received 1 mg morphine sulfate diluted by 4 cc normal saline 0.5% using nebulizer once daily for 5 days and group 2 serving as control who received normal saline as placebo. They were visited by pulmonologist 7 times per day to check symptoms and signs and adverse events. Different parameters including patient-scored peak expiratory flow using pick flow meter, visual analogue scale (VAS) for dyspnea, global quality of life and cough, and number of respiratory rate, night time awaking for dyspnea and cough have been assessed. Results. The scores of VAS for dyspnea, cough and quality of life and also respiratory rate, heart rate, and night time awaking due to dyspnea and night time awaking due to cough improved significantly after morphine nebulization without any major adverse events. Also pick expiratory flow has been improved significantly after nebulization in each day. Conclusion. Our results showed the clinical benefit of nebulized morphine on respiratory complaints of patients due to exposure to SM without significant side effects. PMID:22530119

  4. Gene Therapy Induces Antigen-Specific Tolerance in Experimental Collagen-Induced Arthritis

    PubMed Central

    Jirholt, Pernilla; Turesson, Olof; Wing, Kajsa; Holmdahl, Rikard; Kihlberg, Jan; Stern, Anna; Mårtensson, Inga-Lill; Henningsson, Louise; Gustafsson, Kenth; Gjertsson, Inger

    2016-01-01

    Here, we investigate induction of immunological tolerance by lentiviral based gene therapy in a mouse model of rheumatoid arthritis, collagen II-induced arthritis (CIA). Targeting the expression of the collagen type II (CII) to antigen presenting cells (APCs) induced antigen-specific tolerance, where only 5% of the mice developed arthritis as compared with 95% of the control mice. In the CII-tolerized mice, the proportion of Tregs as well as mRNA expression of SOCS1 (suppressors of cytokine signaling 1) increased at day 3 after CII immunization. Transfer of B cells or non-B cell APC, as well as T cells, from tolerized to naïve mice all mediated a certain degree of tolerance. Thus, sustainable tolerance is established very early during the course of arthritis and is mediated by both B and non-B cells as APCs. This novel approach for inducing tolerance to disease specific antigens can be used for studying tolerance mechanisms, not only in CIA but also in other autoimmune diseases. PMID:27159398

  5. DETECTORS AND EXPERIMENTAL METHODS: Equivalent properties of single event burnout induced by different sources

    NASA Astrophysics Data System (ADS)

    Yang, Shi-Yu; Cao, Zhou; Da, Dao-An; Xue, Yu-Xiong

    2009-05-01

    The experimental results of single event burnout induced by heavy ions and 252Cf fission fragments in power MOSFET devices have been investigated. It is concluded that the characteristics of single event burnout induced by 252Cf fission fragments is consistent to that in heavy ions. The power MOSFET in the “turn-off" state is more susceptible to single event burnout than it is in the “turn-on" state. The thresholds of the drain-source voltage for single event burnout induced by 173 MeV bromine ions and 252Cf fission fragments are close to each other, and the burnout cross section is sensitive to variation of the drain-source voltage above the threshold of single event burnout. In addition, the current waveforms of single event burnouts induced by different sources are similar. Different power MOSFET devices may have different probabilities for the occurrence of single event burnout.

  6. Peripheral site of action of levodropropizine in experimentally-induced cough: role of sensory neuropeptides.

    PubMed

    Lavezzo, A; Melillo, G; Clavenna, G; Omini, C

    1992-06-01

    The mechanism of action of levodropropizine has been investigated in different models of experimentally-induced cough in guinea-pigs. In particular it has been demonstrated that the antitussive drug has a peripheral site of action by injecting the drug intracerebroventricularly (i.c.v.). In these experiments levodropropizine (40 micrograms/50 microliters i.c.v.) did not prevent electrically-induced cough. On the other hand, codeine (5 micrograms/50 microliters i.c.v.) markedly prevented coughing. A difference in the potency ratio of levodropropizine and codeine has been demonstrated in capsaicin-induced cough; after oral administration, codeine was about two to three times more potent than levodropropizine. However, after aerosol administration the two compounds were equipotent. These data might suggest a peripheral site of action for levodropropizine which is related to sensory neuropeptides. Further support for the role of sensory neuropeptides in the mechanism of action of levodropropizine comes from the results obtained in capsaicin-desensitized animals. In this experimental model levodropropizine failed to prevent the vagally elicited cough in neuropeptide-depleted animals, whereas codeine did not differentiate between control and capsaicin-treated animals. In conclusion, our results support the suggestion that levodropropizine has a peripheral site of action. In addition, the interference with the sensory neuropeptide system may explain, at least in part, its activity in experimentally-induced cough.

  7. Peripheral site of action of levodropropizine in experimentally-induced cough: role of sensory neuropeptides.

    PubMed

    Lavezzo, A; Melillo, G; Clavenna, G; Omini, C

    1992-06-01

    The mechanism of action of levodropropizine has been investigated in different models of experimentally-induced cough in guinea-pigs. In particular it has been demonstrated that the antitussive drug has a peripheral site of action by injecting the drug intracerebroventricularly (i.c.v.). In these experiments levodropropizine (40 micrograms/50 microliters i.c.v.) did not prevent electrically-induced cough. On the other hand, codeine (5 micrograms/50 microliters i.c.v.) markedly prevented coughing. A difference in the potency ratio of levodropropizine and codeine has been demonstrated in capsaicin-induced cough; after oral administration, codeine was about two to three times more potent than levodropropizine. However, after aerosol administration the two compounds were equipotent. These data might suggest a peripheral site of action for levodropropizine which is related to sensory neuropeptides. Further support for the role of sensory neuropeptides in the mechanism of action of levodropropizine comes from the results obtained in capsaicin-desensitized animals. In this experimental model levodropropizine failed to prevent the vagally elicited cough in neuropeptide-depleted animals, whereas codeine did not differentiate between control and capsaicin-treated animals. In conclusion, our results support the suggestion that levodropropizine has a peripheral site of action. In addition, the interference with the sensory neuropeptide system may explain, at least in part, its activity in experimentally-induced cough. PMID:1611233

  8. Geographic Health's Way to Prevention of Diseases: A Case Study on Arsenic Spatial Dispersion and Dyspnea in Isfahan Province

    PubMed Central

    Rashidi, Maasoume; Poursafa, Parinaz

    2014-01-01

    Background: As geographic science discusses the analysis of environment, human beings and their mutual relations, thus the field of medical geography consists of being inspired from the relations between these two factors, analyzing environmental factors, their identification them and the state of their effects on human health, as well as determining the location of these factors. Some hazards that threat human health are the results of environmental factors and the relevant pollutions. Some important categories of diseases including (Shortness of Breath or, Dyspnea) have considerable differences in various places, as observed in their spatial prevalence and distribution maps. Methods: The record of patients with Dyspnea diseases were prepared for this descriptive research, for the period of 2009-2011, from the provincial health center, with the questionnaires were excluded patients with a family history of disease and the spatial diagram for disease prevalence was drawn according to the prepared data. The arsenic geographical distribution diagram in Isfahan province was also prepared and then the relation between an element of Arsenic in the province and the Dyspnea diseases were analyzed. Results: The analyses showed that the highest rate of Arsenic is entered the soil via fertilizers to come eventually into the food cycle of humans. By analyzing the amount of used fertilizers in Isfahan province and the dispersion diagram of Arsenic in Isfahan province, it was found that the highest frequency of Arsenic is in places having agricultural base. The spatial dispersion of Dyspnea diseases also showed that the spreading of Dyspnea diseases is greater in places with higher scale of Arsenic. Conclusions: This study is a logical justification between the two diagrams to confirm the hypothesis regarding the effect of arsenic on Dyspnea. PMID:25538832

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

    PubMed

    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.

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

    PubMed Central

    Dominguez, Elisa; Raoul, William; Calippe, Bertrand; Sahel, José-Alain; Guillonneau, Xavier; Paques, Michel; Sennlaub, Florian

    2015-01-01

    Aims 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. Methods and Results 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. Conclusion 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. PMID:26208283

  11. Experimental models of virus-induced demyelination of the central nervous system.

    PubMed

    Dal Canto, M C; Rabinowitz, S G

    1982-02-01

    One of the arguments in favor of a viral pathogenesis for multiple sclerosis is the existence of several experimental and natural animal models of virus-induced primary demyelination. This review deals comprehensively with such models. Well-known examples of demyelinating viral infections in their natural host are JHM, Theiler, visna, and canine distemper encephalomyelitides. Recent reports of experimental murine infections with pathogens such as vesicular stomatitis, Chandipura, herpes simplex, Venezuelan equine encephalomyelitis, and Semliki Forest viruses are also discussed. The thrust of the review is to include viral models suspected of producing primary demyelination on an immunopathological basis.

  12. A 29-Year-Old Man With Nonproductive Cough, Exertional Dyspnea, and Chest Discomfort.

    PubMed

    Halpenny, Darragh; Suh, James; Garofano, Suzette; Alpert, Jeffrey

    2015-09-01

    A 29-year-old man presented with a 5-month history of worsening dry cough, exertional dyspnea, chest tightness, and palpitations. He had been treated by his primary care physician with trials of guaifenesin/codeine, azithromycin, albuterol, and omeprazole without improvement. He denied wheezing, fever, sweats, anorexia, joint pain, swelling, or rash. He had no past medical history. He denied a history of tobacco smoking or IV drug use. He kept no pets, worked as a manager in an office environment, and had no history of occupational inhalational exposure. He reported using aerosolized insect spray to eradicate bed bugs in his house shortly before the cough began but did not report any acute symptoms when using the spray. PMID:26324141

  13. Nontraumatic head and neck emergencies: a clinical approach. Part 1: cervicofacial swelling, dysphagia, and dyspnea.

    PubMed

    Brea Álvarez, B; Tuñón Gómez, M; Esteban García, L; García Hidalgo, C Y; Ruiz Peralbo, R M

    2016-01-01

    Nontraumatic emergencies of the head and neck represent a challenge in the field of neuroradiology for two reasons: first, they affect an area where the thorax joins the cranial cavity and can thus compromise both structures; second, they are uncommon, so they are not well known. Various publications focus on nontraumatic emergencies of the head and neck from the viewpoints of anatomic location or of particular diseases. However, these are not the most helpful viewpoints for dealing with patients in the emergency department, who present with particular signs and symptoms. We propose an analysis starting from the four most common clinical presentations of patients who come to the emergency department for nontraumatic head and neck emergencies: cervical swelling, dysphagia, dyspnea, and loss of vision. Starting from these entities, we develop an approach to the radiologic management and diagnosis of these patients.

  14. Experimental study of the spectral characteristics of laser-induced air plasma

    SciTech Connect

    Lin Zhaoxiang; Wu Jinquan; Sun Fenglou; Gong Shunsheng

    2010-05-01

    The characteristics of laser-induced air, N2, and O2 plasma spectra are investigated spectroscopically. The study concentrates mainly on the temporal behavior of laser-induced plasma after breakdown. We used delayed spectra and spectra evolution for this study. Except for the general one-beam laser-induced breakdown experiment, a second laser beam was added to further probe the behavior of plasma during its decay. We report the experimental results of spectra composition, spectra time evolution, and spectra affected by a second laser beam. We determined that all the laser-induced air plasma spectra are from a continuous spectrum and some line spectra superposed on the continuous spectrum. The stronger short wavelength continuous spectrum is caused by bremsstrahlung radiation of electrons in the plasma, and the weaker long wavelength continuous spectrum is caused by electron and ion recombination. Line spectra originate from excited molecules, atoms, and their first-order ions, but no line spectra form higher-order ions. The results show that the temporal behavior of some spectra is a decay-rise-redecay pattern. With the two laser beam experiment we found that all the spectra intensities are enhanced by the second laser beam, but the response of various spectra to the delay of the second laser beam is quite different, in particular, the intensity increments of some spectra increase with the delay of the second laser beam. Some microscopic processes of laser-induced plasma obtained from the experimental results are discussed. These results are useful for a better understanding of some laser-induced air plasma related applications, such as laser-guided lightning and laser-induced breakdown spectroscopy.

  15. The effect of various drugs on experimentally induced ulcers in immobilized rats

    NASA Technical Reports Server (NTRS)

    Schramm, H.

    1978-01-01

    Experiments related to the importance of functional disorders in the central nervous system in connection with stomach diseases were performed on Wistar rats. Assuming that severe mental strains may be triggering factors for such disorders, testing of the effects of different drugs on experimentally induced ulcers in these rats was done. The immobilization method described by Bonfils was used. Particular importance was placed on the sex related difference which appeared.

  16. Gallic acid attenuates dextran sulfate sodium-induced experimental colitis in BALB/c mice

    PubMed Central

    Pandurangan, Ashok Kumar; Mohebali, Nooshin; Norhaizan, Mohd Esa; Looi, Chung Yeng

    2015-01-01

    Gallic acid (GA) is a polyhydroxy phenolic compound that has been detected in various natural products, such as green tea, strawberries, grapes, bananas, and many other fruits. In inflammatory bowel disease, inflammation is promoted by oxidative stress. GA is a strong antioxidant; thus, we evaluated the cytoprotective and anti-inflammatory role of GA in a dextran sulfate sodium (DSS)-induced mouse colitis model. Experimental acute colitis was induced in male BALB/c mice by administering 2.5% DSS in the drinking water for 7 days. The disease activity index; colon weight/length ratio; histopathological analysis; mRNA expressions of IL-21 and IL-23; and protein expression of nuclear erythroid 2-related factor 2 (Nrf2) were compared between the control and experimental mice. The colonic content of malondialdehyde and the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase activity were examined as parameters of the redox state. We determined that GA significantly attenuated the disease activity index and colon shortening, and reduced the histopathological evidence of injury. GA also significantly (P<0.05) reduced the expressions of IL-21 and IL-23. Furthermore, GA activates/upregulates the expression of Nrf2 and its downstream targets, including UDP-GT and NQO1, in DSS-induced mice. The findings of this study demonstrate the protective effect of GA on experimental colitis, which is probably due to an antioxidant nature of GA. PMID:26251571

  17. Analytical and experimental study of flow phenomena in noncavitating rocket pump inducers

    NASA Technical Reports Server (NTRS)

    Lakshminarayana, B.

    1981-01-01

    The flow processes in rocket pump inducers are summarized. The experimental investigations were carried out with air as the test medium. The major characteristics features of the rocket pump inducers are low flow coefficient (0.05 to 0.2) large stagger angle (70 deg to 85 deg) and high solidity blades of little or no camber. The investigations are concerned with the effect of viscosity not the effects of cavitation. Flow visualization, conventional and hot wire probe measurement inside and at the exit of the blade passage, were the analytical methods used. The experiment was carried out using four three and two bladed inducers with cambered blades. Both the passage and the exit flow were measured. The basic research and boundary layer investigation was carried out using a helical flat plate (of some dimensions as the inducer blades tested), and flat plate helical inducer (four bladed). Detailed mean and turbulence flow field inside the passage as well as the exit of the rotor were derived from these measurement. The boundary layer, endwall, and other passage data reveal extremely complex nature of the flow, with major effects of viscosity present across the entire passage. Several analyses were carried out to predict the flow field in inducers. These included an approximate analysis, the shear pumping analysis, and a numerical solution of exact viscous equations with approximate modeling for the viscous terms.

  18. Opioid-induced hyperalgesia (OIH): a real clinical problem or just an experimental phenomenon?

    PubMed

    Eisenberg, Elon; Suzan, Erica; Pud, Dorit

    2015-03-01

    Although opioid-induced hyperalgesia (OIH) is mentioned as a potential cause of opioid dose escalation without adequate analgesia, true evidence in support of this notion is relatively limited. Most studies conducted in the context of acute and experimental pain, which seemingly demonstrated evidence for OIH, actually might have measured other phenomena such as acute opioid withdrawal or tolerance. OIH studies in patients with chronic pain have used various experimental pain models (such as cold pain tolerance or heat pain intensity). Therefore, the fact that they have yielded inconsistent results is hard to interpret. Thus far, with the exception of a few clinical case reports on OIH in patients with cancer pain and one prospective study in patients with chronic neuropathic pain, evidence for OIH in patients with chronic or cancer-related pain is lacking. Whether experimental pain models are necessary for establishing the clinical diagnosis of OIH, and which specific model is preferred, are yet to be determined. PMID:25128284

  19. Opioid-induced hyperalgesia (OIH): a real clinical problem or just an experimental phenomenon?

    PubMed

    Eisenberg, Elon; Suzan, Erica; Pud, Dorit

    2015-03-01

    Although opioid-induced hyperalgesia (OIH) is mentioned as a potential cause of opioid dose escalation without adequate analgesia, true evidence in support of this notion is relatively limited. Most studies conducted in the context of acute and experimental pain, which seemingly demonstrated evidence for OIH, actually might have measured other phenomena such as acute opioid withdrawal or tolerance. OIH studies in patients with chronic pain have used various experimental pain models (such as cold pain tolerance or heat pain intensity). Therefore, the fact that they have yielded inconsistent results is hard to interpret. Thus far, with the exception of a few clinical case reports on OIH in patients with cancer pain and one prospective study in patients with chronic neuropathic pain, evidence for OIH in patients with chronic or cancer-related pain is lacking. Whether experimental pain models are necessary for establishing the clinical diagnosis of OIH, and which specific model is preferred, are yet to be determined.

  20. Radiological and histopathological evaluation of experimentally-induced periapical lesion in rats

    PubMed Central

    TEIXEIRA, Renata Cordeiro; RUBIRA, Cassia Maria Fischer; ASSIS, Gerson Francisco; LAURIS, José Roberto Pereira; CESTARI, Tania Mary; RUBIRA-BULLEN, Izabel Regina Fischer

    2011-01-01

    Objective This study evaluated experimentally-induced periapical bone loss sites using digital radiographic and histopathologic parameters. Material and Methods Twenty-seven Wistar rats were submitted to coronal opening of their mandibular right first molars. They were radiographed at 2, 15 and 30 days after the operative procedure by two digital radiographic storage phosphor plates (Digora®). The images were analyzed by creating a region of interest at the periapical region of each tooth (ImageJ) and registering the corresponding pixel values. After the sacrifice, the specimens were submitted to microscopic analysis in order to confirm the pulpal and periapical status of the tooth. Results There was significant statistically difference between the control and test sides in all the experimental periods regarding the pixel values (two-way ANOVA; p<0.05). Conclusions The microscopic analysis proved that a periapical disease development occurred during the experimental periods with an evolution from pulpal necrosis to periapical bone resorption. PMID:21922123

  1. The role of experimentally-induced subacromial pain on shoulder strength and throwing accuracy.

    PubMed

    Wassinger, Craig A; Sole, Gisela; Osborne, Hamish

    2012-10-01

    Shoulder injuries often comprise two separate yet related components, structural tissue damage and pain. The role of each of these components on shoulder function is difficult to ascertain. Experimental pain models allow the assessment of consequences of localized pain when applied to healthy individuals. By understanding the role of pain on shoulder function, clinicians will be able to more efficiently assess and treat shoulder injuries. The objective of the study was to evaluate the role of experimentally-induced sub-acromial pain on shoulder isokinetic rotational strength and throwing accuracy. This was a block counterbalanced, crossover, repeated measures study design utilizing 20 individuals without self-reported shoulder or cervical pathology. Shoulder function was measured with and without experimental pain injection (2 mL of 5% hypertonic saline) in the sub-acromial space. Functional tasks consisted of shoulder rotational strength utilizing isokinetic testing and throwing accuracy via the functional throwing performance index. The hypertonic saline induced moderate pain levels in all participants (4.3-5.1/10). Normalized shoulder internal (t = 3.76, p = 0.001) and external (t = 3.12, p = 0.006) rotation strength were both diminished in the painful condition compared to the pain free condition. Throwing accuracy was also reduced while the participants experienced pain (t = 3.99, p = 0.001). Moderate levels of experimental shoulder pain were sufficient to negatively influence shoulder strength and throwing accuracy in participants without shoulder pathology.

  2. Sex Differences in Experimentally Induced Colitis in Mice: a Role for Estrogens.

    PubMed

    Bábíčková, Janka; Tóthová, Ľubomíra; Lengyelová, Eva; Bartoňová, Anastázie; Hodosy, Július; Gardlík, Roman; Celec, Peter

    2015-10-01

    Sex differences have been found in the incidence and progression of inflammatory bowel diseases (IBD) such as ulcerative colitis and Crohn's disease. The reported differences in observational studies are controversial, and the effects of sex hormones on the pathogenesis of IBD are not clear. The aim of this study was to analyze sex differences in the progression of experimentally induced colitis. Experimental colitis was induced in adult mice by adding 2% dextran sodium sulfate (DSS) into drinking water. Male and female mice were used as intact, gonadectomized, and supplemented with either estradiol or testosterone. In comparison to males, female mice with induced colitis had significantly longer colon (p < 0.05), lower decrease in body weight (p < 0.001), and lower stool consistency score (p < 0.05). Histopathological analysis showed less inflammatory infiltrates (p < 0.001) and crypt damage (p < 0.001) in female mice. Female mice with colitis had also lower concentration of TNF-α in colon homogenates (p < 0.01). Supplementation with estradiol in ovariectomized mice ameliorated the severity of colitis. Female mice are partially protected against chemically induced colitis. This protection seems to be mediated by estradiol.

  3. Duration of Analgesia Induced by Acupuncture-Like TENS on Experimental Heat Pain

    PubMed Central

    Brochu, Marilyne; Dupuis-Michaud, Cynthia; Pagé, Catherine; Popovic, Draga; Simard, Marie-Eve

    2013-01-01

    Background. Acupuncture-like TENS (AL-TENS) is a treatment modality that can be used to temporarily reduce pain. However, there is no clear data in the literature regarding the specific duration of analgesia induced by AL-TENS. Objectives. To describe and quantify the duration and magnitude of AL-TENS analgesia on experimental heat pain in healthy subjects and verify if the duration or magnitude of analgesia induced by the AL-TENS was influenced by the duration of the application of the AL-TENS (15 versus 30 minutes). Methods. A repeated-measures, intrasubject randomized experimental design was used, where each participant was his/her own control. 22 healthy volunteers underwent heat pain stimulations with a contact thermode before (pretest) and after (posttest) AL-TENS application (15 and 30 minutes). Outcome measures included subjective pain during AL-TENS, duration, and magnitude of AL-TENS-induced analgesia. Results. Survival analysis showed that the median duration of AL-TENS analgesia was 10 minutes following the application of either 15 or 30 minutes of AL-TENS. The magnitude of analgesia following either application was comparable at all points in time (P values > 0.05) and ranged between −20% and −36% pain reduction. Conclusion. Only half of the participants still had heat-pain analgesia induced by the AL-TENS at 15 minutes postapplication. PMID:27335882

  4. Effect of ranitidine on healing of experimentally induced gastric ulcers in ponies.

    PubMed

    MacAllister, C G; Sangiah, S

    1993-07-01

    Thirty young ponies were examined endoscopically for evidence of gastric ulceration. Seven ponies had noninduced gastric ulcers present at the initial examination and were eliminated from the study. In an attempt to induce gastric ulcers experimentally, flunixin meglumine (1.1 mg/kg of body weight, IM, q 8 h) was administered for 7 days to the 23 ponies with endoscopically normal gastric mucosa. During the 7 days of flunixin administration, 11 ponies developed gastric ulcers that were appropriate for study. The 11 ponies were randomly allotted to 2 groups. Group-A (n = 5) and group-B (n = 6) ponies received ranitidine (4.4 mg/kg, PO, q 8 h) and corn syrup, respectively, until ulcers healed or for a maximum of 40 days. General anesthesia was induced every 3 to 5 days for visual evaluation of ulcer healing by use of a video endoscope. The earliest complete healing of gastric lesions observed in a corn syrup-treated pony was at 17 days. At 40 days, 3 of 5 and 3 of 6 ponies of the ranitidine and corn syrup-treated groups, respectively, had healed ulcers. Results of this study indicate that: noninduced gastric ulcers may be common in young ponies, flunixin meglumine may be effective in inducing gastric ulcers for gastric healing studies in young ponies, and ranitidine (4.4 mg/kg, q 8 h) is not significantly effective in accelerating healing of experimentally induced gastric ulcers in ponies under conditions of this study. PMID:8368605

  5. Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

    PubMed Central

    Wegner, Alexander; Elsenbruch, Sigrid; Rebernik, Laura; Roderigo, Till; Engelbrecht, Elisa; Jäger, Marcus; Engler, Harald; Schedlowski, Manfred; Benson, Sven

    2015-01-01

    Abstract A role of the innate immune system is increasingly recognized as a mechanism contributing to pain sensitization. Experimental administration of the bacterial endotoxin lipopolysaccharide (LPS) constitutes a model to study inflammation-induced pain sensitization, but all existing human evidence comes from male participants. We assessed visceral and musculoskeletal pain sensitivity after low-dose LPS administration in healthy men and women to test the hypothesis that women show greater LPS-induced hyperalgesia compared with men. In this randomized, double-blind, placebo-controlled crossover study, healthy men (n = 20) and healthy women using oral contraceptives (n = 20) received an intravenous injection of 0.4 ng/kg body weight LPS or placebo. Pain sensitivity was assessed with established visceral and musculoskeletal pain models (ie, rectal pain thresholds; pressure pain thresholds for different muscle groups), together with a heartbeat perception (interoceptive accuracy) task. Plasma cytokines (tumor necrosis factor-α and interleukin-6) were measured along with state anxiety at baseline and up to 6-hour postinjection. Lipopolysaccharide application led to significant increases in plasma cytokines and state anxiety and decreased interoceptive awareness in men and women (P < 0.001, condition effects), with more pronounced LPS-induced cytokine increases in women (P < 0.05, interaction effects). Although both rectal and pressure pain thresholds were significantly decreased in the LPS condition (all P < 0.05, condition effect), no sex differences in endotoxin-induced sensitization were observed. In summary, LPS-induced systemic immune activation leads to visceral and musculoskeletal hyperalgesia, irrespective of biological sex. These findings support the broad applicability of experimental endotoxin administration as a translational preclinical model of inflammation-induced pain sensitization in both sexes. PMID:26058036

  6. Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

    PubMed

    Wegner, Alexander; Elsenbruch, Sigrid; Rebernik, Laura; Roderigo, Till; Engelbrecht, Elisa; Jäger, Marcus; Engler, Harald; Schedlowski, Manfred; Benson, Sven

    2015-10-01

    A role of the innate immune system is increasingly recognized as a mechanism contributing to pain sensitization. Experimental administration of the bacterial endotoxin lipopolysaccharide (LPS) constitutes a model to study inflammation-induced pain sensitization, but all existing human evidence comes from male participants. We assessed visceral and musculoskeletal pain sensitivity after low-dose LPS administration in healthy men and women to test the hypothesis that women show greater LPS-induced hyperalgesia compared with men. In this randomized, double-blind, placebo-controlled crossover study, healthy men (n = 20) and healthy women using oral contraceptives (n = 20) received an intravenous injection of 0.4 ng/kg body weight LPS or placebo. Pain sensitivity was assessed with established visceral and musculoskeletal pain models (ie, rectal pain thresholds; pressure pain thresholds for different muscle groups), together with a heartbeat perception (interoceptive accuracy) task. Plasma cytokines (tumor necrosis factor-α and interleukin-6) were measured along with state anxiety at baseline and up to 6-hour postinjection. Lipopolysaccharide application led to significant increases in plasma cytokines and state anxiety and decreased interoceptive awareness in men and women (P < 0.001, condition effects), with more pronounced LPS-induced cytokine increases in women (P < 0.05, interaction effects). Although both rectal and pressure pain thresholds were significantly decreased in the LPS condition (all P < 0.05, condition effect), no sex differences in endotoxin-induced sensitization were observed. In summary, LPS-induced systemic immune activation leads to visceral and musculoskeletal hyperalgesia, irrespective of biological sex. These findings support the broad applicability of experimental endotoxin administration as a translational preclinical model of inflammation-induced pain sensitization in both sexes.

  7. Inflammation-induced pain sensitization in men and women: does sex matter in experimental endotoxemia?

    PubMed

    Wegner, Alexander; Elsenbruch, Sigrid; Rebernik, Laura; Roderigo, Till; Engelbrecht, Elisa; Jäger, Marcus; Engler, Harald; Schedlowski, Manfred; Benson, Sven

    2015-10-01

    A role of the innate immune system is increasingly recognized as a mechanism contributing to pain sensitization. Experimental administration of the bacterial endotoxin lipopolysaccharide (LPS) constitutes a model to study inflammation-induced pain sensitization, but all existing human evidence comes from male participants. We assessed visceral and musculoskeletal pain sensitivity after low-dose LPS administration in healthy men and women to test the hypothesis that women show greater LPS-induced hyperalgesia compared with men. In this randomized, double-blind, placebo-controlled crossover study, healthy men (n = 20) and healthy women using oral contraceptives (n = 20) received an intravenous injection of 0.4 ng/kg body weight LPS or placebo. Pain sensitivity was assessed with established visceral and musculoskeletal pain models (ie, rectal pain thresholds; pressure pain thresholds for different muscle groups), together with a heartbeat perception (interoceptive accuracy) task. Plasma cytokines (tumor necrosis factor-α and interleukin-6) were measured along with state anxiety at baseline and up to 6-hour postinjection. Lipopolysaccharide application led to significant increases in plasma cytokines and state anxiety and decreased interoceptive awareness in men and women (P < 0.001, condition effects), with more pronounced LPS-induced cytokine increases in women (P < 0.05, interaction effects). Although both rectal and pressure pain thresholds were significantly decreased in the LPS condition (all P < 0.05, condition effect), no sex differences in endotoxin-induced sensitization were observed. In summary, LPS-induced systemic immune activation leads to visceral and musculoskeletal hyperalgesia, irrespective of biological sex. These findings support the broad applicability of experimental endotoxin administration as a translational preclinical model of inflammation-induced pain sensitization in both sexes. PMID:26058036

  8. Agreement between a simple dyspnea-guided treatment algorithm for stable COPD and the GOLD guidelines: a pilot study

    PubMed Central

    Cabrera, Carlos; Casanova, Ciro; Martín, Yolanda; Mirabal, Virginia; Sánchez, María del Carmen; Álvarez, Felisa; Juliá, Gabriel; Cabrera-Navarro, Pedro; García-Bello, Miguel Ángel; Marín, José María; de-Torres, Juan Pablo; Divo, Miguel; Celli, Bartolomé

    2016-01-01

    Introduction Guidelines recommendations for the treatment of COPD are poorly followed. This could be related to the complexity of classification and treatment algorithms. The purpose of this study was to validate a simpler dyspnea-based treatment algorithm for inhaled pharmacotherapy in stable COPD, comparing its concordance with the current Global Initiative for Obstructive Lung Disease (GOLD) guideline. Methods We enrolled patients who had been diagnosed with COPD in three primary care facilities and two tertiary hospitals in Spain. We determined anthropometric data, forced expiratory volume in the 1st second (percent), exacerbations, and dyspnea based on the modified Medical Research Council scale. We evaluated the new algorithm based on dyspnea and exacerbations and calculated the concordance with the current GOLD recommendations. Results We enrolled 100 patients in primary care and 150 attending specialized care in a respiratory clinic. There were differences in the sample distribution between cohorts with 41% vs 26% in grade A, 16% vs 12% in grade B, 16% vs 22% in grade C, and 27% vs 40% in grade D for primary and respiratory care, respectively (P=0.005). The coincidence of the algorithm with the GOLD recommendations in primary care was 93% and 91.8% in the respiratory care cohort. Conclusion A simple dyspnea-based treatment algorithm for inhaled pharmacotherapy of COPD could be useful in the management of COPD patients and concurs very well with the recommended schema suggested by the GOLD initiative. PMID:27354780

  9. Effects of Guchang Capsule on Dextran Sulphate Sodium-Induced Experimental Ulcerative Colitis in Mice

    PubMed Central

    Liu, Baoshan; Liu, Tong; Wang, Xiaohong; Zheng, Xin; Wang, Hong; Ma, Lin

    2016-01-01

    Guchang capsule (GC) is a Chinese materia medica standardized product extracted from 15 Chinese traditional medical herbs and it has been clinically used in the treatment of intestinal disease. In this study, in order to extend the research of GC in intestinal disease, we were aiming to evaluate potential effects of GC on dextran sulphate sodium- (DSS-) induced murine experimental colitis and to elucidate the underlying mechanisms. GC treatment attenuated DSS-induced body weight loss and reduced the mortality. Moreover, GC treatment prevented DSS-induced colonic pathological damage; meanwhile it inhibited proinflammatory cytokines production in colon tissues. In vitro, GC significantly reduced LPS-induced proinflammatory cytokines production via inhibiting the activation of NF-κB in macrophage cells, and the expressions of several long noncoding RNAs (lncRNAs) which were reported in regulating NF-κB signaling pathway were obviously affected by adding GC into culture medium. In conclusion, our data suggested that administration of GC exhibits therapeutic effects on DSS-induced colitis partially through regulating the expression of NF-κB related lncRNAs in infiltrating immune cells. PMID:27313642

  10. Experimental investigations on flow induced vibration of an externally excited flexible plate

    NASA Astrophysics Data System (ADS)

    Purohit, Ashish; Darpe, Ashish K.; Singh, S. P.

    2016-06-01

    Flow-induced vibration of a harmonically actuated flexible plate in the wake of an upstream bluff body is experimentally investigated. The experiments are performed in an open-ended wind tunnel. A flexible plate trailing a bluff body is under fluid induced excitation due to the flowing fluid. The additional external excitation to the trailing plate is applied using an electro-magnetic exciter. The frequency and amplitude of the external harmonic excitation are selected as variable parameters in the experiments and their effect on the plate vibration and is investigated. To know the nature of acoustic pressure wave generated from the vibrating system, near-field acoustic pressure is also measured. A laser vibrometer, a pressure microphone and a high-speed camera are employed to measure the plate vibration, pressure signal, and instantaneous images of the plate motion respectively. The results obtained indicate that the dynamics of the plate is influenced by both the flow-induced excitation and external harmonic excitation. When frequency of the two excitations is close enough, a large vibration level and a high tonal sound pressure are observed. At higher amplitude of external excitation, the frequency component corresponding to the flow-induced excitation is found to reduce significantly in the frequency spectrum of the vibration signal. It is observed that, for certain range of excitation frequency, the plate vibration first reduces, reaches a minimum value and then increases with increase in the level of external excitation. A fair qualitative agreement of the experimental results with numerical simulation result of the past study has been noted. In addition to the experiments, the role of phase difference between the flow-induced excitation generated from the front obstacle and externally applied harmonic excitation is investigated through numerical simulations. The result obtained reveals that the final steady state vibration of the coupled system is

  11. Experimental rat model for alcohol-induced osteonecrosis of the femoral head

    PubMed Central

    Okazaki, Shunichiro; Nagoya, Satoshi; Tateda, Kenji; Katada, Ryuichi; Mizuo, Keisuke; Watanabe, Satoshi; Yamashita, Toshihiko; Matsumoto, Hiroshi

    2013-01-01

    Alcohol-induced osteonecrosis of the femoral head (ONFH) is observed in alcohol abusers and patients with alcoholic fatty liver disease. It has been reported that Toll-like receptor 4 (TLR4) signalling plays a crucial role in the pathogenesis of alcoholic fatty liver disease. We previously reported a corticosteroid-induced ONFH rat model, and suggested that TLR4 signalling contributes to the pathogenesis of ONFH. Thus, it is thought that the pathogenesis of alcohol-induced ONFH is probably similar to that of corticosteroid-induced ONFH. The aim of this study was to develop a new animal model for alcohol-induced ONFH and to evaluate the relationship between the pro-inflammatory response via TLRs and the development of ONFH in rats. Male Wistar rats were fed a Lieber–DeCarli liquid diet containing 5% ethanol (experimental group) or dextran (control group) for 1–24 weeks. Histopathological and biochemical analyses were performed. Feeding the ethanol-containing liquid diet resulted in the development of ONFH with hepatic steatosis, hepatic dysfunction and hyperlipidaemia, whereas feeding the dextran-containing diet did not cause ONFH. However, we could not recognize any relationship between the pro-inflammatory response via TLR4 and the development of alcohol-induced ONFH. Thus in this study we have developed a new rat model for alcohol-induced ONFH based on the feeding of an ethanol liquid diet. ONFH was observed within seven days from the start of feeding with 5% ethanol-containing liquid diet. Although this was linked to hepatic steatosis, a TLR4 association was not a feature of this model. PMID:24020403

  12. Preliminary investigation of cardiopulmonary function in stroke patients with stable heart failure and exertional dyspnea

    PubMed Central

    Liaw, Mei-Yun; Wang, Lin-Yi; Pong, Ya-Ping; Tsai, Yu-Chin; Huang, Yu-Chi; Yang, Tsung-Hsun; Lin, Meng-Chih

    2016-01-01

    Abstract The aim of this study was to investigate the relationships between pulmonary function, respiratory muscle strength, perceived dyspnea, degree of fatigue, and activity of daily living with motor function and neurological status in stroke patients with stable congestive heart failure (CHF). This was a cohort study in a tertiary care medical center. Stroke patients with CHF and exertional dyspnea (New York Heart Association class I–III) were recruited. The baseline characteristics included duration of disease, Brunnstrom stage, spirometry, resting heart rate, resting oxyhemoglobin saturation (SpO2), maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), Borg scale, fatigue scale, and Barthel index. A total of 47 stroke patients (24 males, 23 females, mean age 65.9 ± 11.5 years) were included. The average Brunnstrom stages of affected limbs were 3.6 ± 1.3 over the proximal parts and 3.5 ± 1.4 over the distal parts of upper limbs, and 3.9 ± 0.9 over lower limbs. The average forced vital capacity (FVC) was 2.0 ± 0.8 L, with a predicted FVC% of 67.9 ± 18.8%, forced expiratory volume in the first second (FEV1) of 1.6 ± 0.7 L, predicted FEV1% of 70.6 ± 20.1%, FEV1/FVC of 84.2 ± 10.5%, and maximum mid-expiratory flow of 65.4 ± 29.5%. The average MIP and MEP were −52.9 ± 33.3 cmH2O and 60.8 ± 29.0 cmH2O, respectively. The Borg scale was 1.5 ± 0.8. MIP was negatively associated with the average Brunnstrom stage of the proximal (r = −0.318, P < 0.05) and distal (r = −0.391, P < 0.01) parts of the upper extremities and lower extremities (r = −0.288, P < 0.05), FVC (r = −0.471, P < 0.01), predicted FVC% (r = −0.299, P < 0.05), and FEV1 (r = −0.397, P < 0.01). MEP was positively associated with average Brunnstrom stage of the distal area of the upper extremities (r = 0.351, P < 0.05), FVC (r = 0.526, P < 0

  13. Effect of experimentally induced low back pain on postural sway with breathing.

    PubMed

    Smith, Michelle; Coppieters, Michel W; Hodges, Paul W

    2005-09-01

    Although breathing perturbs balance, in healthy individuals little sway is detected in ground reaction forces because small movements of the spine and lower limbs compensate for the postural disturbance. When people have chronic low back pain (LBP), sway at the ground is increased, possibly as a result of reduced compensatory motion of the trunk. The aim of this study was to determine whether postural compensation for breathing is reduced during experimentally induced pain. Subjects stood on a force plate with eyes open, eyes closed, and while breathing with hypercapnoea before and after injection of hypertonic saline into the right lumbar longissimus muscle to induce LBP. Motion of the lumbar spine, pelvis, and lower limbs was measured with four inclinometers fixed over bony landmarks. During experimental pain, motion of the trunk in association with breathing was reduced. However, despite this reduction in motion, there was no increase in postural sway with breathing. These data suggest that increased body sway with breathing in people with chronic LBP is not simply because of reduced trunk movement, but instead, indicates changes in coordination by the central nervous system that are not replicated by experimental nociceptor stimulation.

  14. The effect of experimentally induced sedentariness on mood and psychobiological responses to mental stress

    PubMed Central

    Endrighi, Romano; Steptoe, Andrew; Hamer, Mark

    2016-01-01

    Background Evidence suggests a link between sedentary behaviours and depressive symptoms. Mechanisms underlying this relationship are not understood, but inflammatory processes may be involved. Autonomic and inflammatory responses to stress may be heightened in sedentary individuals contributing to risk, but no study has experimentally investigated this. Aims To examine the effect of sedentary time on mood and stress responses using an experimental design. Method Forty-three individuals were assigned to a free-living sedentary condition and to a control condition (usual activity) in a cross-over, randomised fashion and were tested in a psychophysiology laboratory after spending 2 weeks in each condition. Participants completed mood questionnaires (General Health Questionnaire and Profile of Mood States) and wore a motion sensor for 4 weeks. Results Sedentary time increased by an average of 32 min/day (P = 0.01) during the experimental condition compared with control. Being sedentary resulted in increases in negative mood independent of changes in moderate to vigorous physical activity (ΔGHQ = 6.23, ΔPOMS = 2.80). Mood disturbances were associated with greater stress-induced inflammatory interleukin-6 (IL-6) responses (β = 0.37). Conclusions Two weeks of exposure to greater free-living sedentary time resulted in mood disturbances independent of reduction in physical activity. Stress-induced IL-6 responses were associated with changes in mood. PMID:26294364

  15. Experimental study to explore the 8Be-induced nuclear reaction via the Trojan horse method

    NASA Astrophysics Data System (ADS)

    Wen, Qun-Gang; Li, Cheng-Bo; Zhou, Shu-Hua; Irgaziev, Bakhadir; Fu, Yuan-Yong; Spitaleri, Claudio; La Cognata, Marco; Zhou, Jing; Meng, Qiu-Ying; Lamia, Livio; Lattuada, Marcello

    2016-03-01

    To explore a possible indirect method for 8Be induced astrophysical reactions, the 8Be=(8Be+n ) cluster structure has been studied via the Trojan horse method. For the first time a 8Be nucleus having an ultrashort lifetime is studied by the Trojan horse method and a 9Be nucleus in the ground state is used for this purpose. The 9Be nucleus is assumed to have a (8Be+n ) cluster structure and used as a Trojan horse nucleus. The 8Be nucleus acts as a participant, while the neutron is a spectator to the virtual 8Be+d →α +6Li reaction via the 3-body reaction 8Be+d →α +6Li+n . The experimental neutron momentum distribution inside 9Be has been reconstructed. The agreement between the experimental momentum distribution and the theoretical one indicates that a (8Be+n ) cluster structure inside 9Be is very likely. Therefore, the experimental study of 8Be induced reactions, for example, the measurement of the 8Be+α →12C reaction proceeding through the Hoyle state, is possible.

  16. Change in serum ferritin concentration in experimentally induced anemia of chronic inflammation in dogs.

    PubMed

    Chikazawa, Seishiro; Nakazawa, Takafumi; Hori, Yasutomo; Hoshi, Fumio; Kanai, Kazutaka; Ito, Naoyuki; Orino, Koichi; Watanabe, Kiyotaka; Higuchi, Seiichi

    2013-11-01

    In veterinary medicine, hyperferritinemia is often observed in dogs with various diseases (e.g., histiocytic sarcoma and immune-mediated hemolytic anemia) without evidence of iron overload. The mechanism underlying hyperferritinemia development is not well understood. Anemia caused by inflammation is termed as anemia of chronic disease (ACD), and experimentally induced ACD is known to cause slight hyperferritinemia. However, almost all these studies were based on short-term acute inflammation. Hepcidin, a protein mainly produced by hepatocytes, is thought to be a key regulator in iron release from reticuloendothelial cells (RECs), and its expression is related to ACD. We hypothesized that in the case of long-term ACD, iron deposition in RECs increases through hepcidin, causing a diachronic increase in serum ferritin levels. In the present study, we used a canine model with repeated subcutaneous administration of turpentine oil every 3 days over a period of 42 days (15 injections) and induced long-term inflammatory conditions; furthermore, we evaluated the change in serum ferritin concentration. Hypoproliferative anemia, bone marrow iron deposition and hypoferremia, which are characteristic of ACD, were observed on administering the turpentine injections. Hepatic iron content, hepatic hepcidin mRNA expression and serum ferritin concentration increased during the early period after turpentine injection, but returned to normal levels later. These results show that experimentally induced long-term ACD caused hypoproliferative anemia without sustained increase in hepcidin expression and did not cause systemic iron overload. Thus, chronic inflammation may not contribute greatly to increase in hyperferritinemia.

  17. Induced oral breathing and craniocervical postural relations: an experimental study in healthy young adults.

    PubMed

    Sforza, Chiarella; Colombo, Anna; Turci, Michela; Grassi, GianPiero; Ferrario, Virgilio F

    2004-01-01

    The influence of induced oral breathing on head and craniocervical posture was studied in ten healthy young adults. After a baseline recording, oral respiration was induced by using a swimmer's type nose clip. The subjects were filmed 15 and 90 minutes after wearing the nose clip, immediately and 15 minutes after taking it off. The angles C7-tragion versus the true vertical, nasion-tragion versus the vertical, and C7-tragion-nasion were calculated, and the difference between the baseline and the four experimental recordings was computed. During the experiment, head and neck positions were modified in all subjects, but with a large variability for both the direction (flexion or extension) and the extent of the modification. Overall, the mean differences were minimal with large standard deviations. Differences between baseline and the experimental recordings were significant only for the C7-tragion versus the vertical angle (analysis of variance, p=0.0083). In conclusion, induced oral respiration may have a significant role in the alteration of head and craniocervical posture, but the effect was highly variable.

  18. Scaling law for bubbles induced by different external sources: theoretical and experimental study.

    PubMed

    Gong, S W; Ohl, S W; Klaseboer, E; Khoo, B C

    2010-05-01

    The scaling relations for bubbles induced by different external sources are investigated based on a modified Rayleigh model and experimental observations. The equations derived from the modified Rayleigh model are presented to describe the collapse of bubbles induced by the different external sources such as electrical spark, laser, and underwater explosion. A scaling law is then formulated to establish the scaling relations between the different types of bubbles. The scaling law reveals the fact that the characteristic length scale factor differs from the characteristic time scale factor for the different types of bubbles. It is then validated by our experimental observations of the spark- and laser-generated bubbles as well as the bubbles induced by underwater explosions from previous published reports. With the present scaling law, studies on spark- or laser-generated bubbles as well as their applications (for example, in industrial or biomedical related applications) can benefit from the experiences and information built up over the years in underwater explosion bubbles. Conversely, it is possible to substitute a spark- or laser-generated bubble for an underwater explosion bubble in the study of a large-scale and complex physical problem.

  19. Paricalcitol may improve oxidative DNA damage on experimental amikacin-induced nephrotoxicity model.

    PubMed

    Bulut, Gulay; Basbugan, Yildiray; Ari, Elif; Erten, Remzi; Bektas, Havva; Alp, Hamit Hakan; Bayram, Irfan

    2016-06-01

    This study aimed to investigate the possible protective effect of paricalcitol on experimental amikacin-induced nephrotoxicity model in rats. Wistar albino rats (n = 32) were allocated into four equal groups of eight each, the control (Group C), paricalcitol (Group P), amikacin-induced nephrotoxicity (Group A), and paricalcitol-treated amikacin-induced nephrotoxicity (Group A + P) groups. Paricalcitol was given intra-peritoneally at a dose of 0.4 μg/kg/d for 5 consecutive days prior to induction of amikacin-induced nephrotoxicity. Intra-peritoneal amikacin (1.2 g/kg) was used to induce nephrotoxicity at day 4. Renal function parameters, oxidative stress biomarkers, oxidative DNA damage (8-hydroxy-2'-deoxyguanosine/deoxyguanosine ratio), kidney histology, and vascular endothelial growth factor (VEGF) immunoexpression were determined. Group A + P had lower mean fractional sodium excretion (p < 0.001) as well as higher creatinine clearance (p = 0.026) than the amikacin group (Group A). Renal tissue malondialdehyde levels (p = 0.035) and serum 8-hydroxy-2'-deoxyguanosine/deoxyguanosine ratio (8-OHdG/dG ratio) (p < 0.001) were significantly lower; superoxide dismutase (p = 0.024) and glutathione peroxidase (p = 0.007) activities of renal tissue were significantly higher in group A + P than in group A. The mean scores of tubular necrosis (p = 0.024), proteinaceous casts (p = 0.038), medullary congestion (p = 0.035), and VEGF immunoexpression (p = 0.018) were also lower in group A + P when compared with group A. This study demonstrates the protective effect of paricalcitol in the prevention of amikacin-induced nephrotoxicity in an experimental model. Furthermore, it is the first study to demonstrate that paricalcitol improves oxidative DNA damage in an experimental acute kidney injury model.

  20. A combined experimental and numerical investigation of roughness induced supersonic boundary layer transition

    NASA Astrophysics Data System (ADS)

    Zhao, Yunfei; Liu, Wei; Xu, Dan; Gang, Dundian; Yi, Shihe

    2016-01-01

    The effect of surface roughness on boundary layer transition is of great importance to hypersonic vehicles. In this paper, both experimental and numerical methods are used to investigate the laminar-turbulent transition of a Mach 3 flat-plate boundary layer induced by isolated roughness element. Good agreements are achieved between experimental data and high-order numerical simulations. It is observed that, with increasing height of roughness, the transition tends to move forward. Two different types of transition mechanisms are found according to the height of the roughness elements. For the smallest roughness height of h=1 mm, the shear layer instability in the wake region appears to be the leading mechanism for transition to turbulence. For two larger roughness elements of h=2 mm and h=4 mm, strong unsteadiness is developed from the upstream separation zone and transition is immediately accomplished, which indicates that the absolute instability in upstream separation zone dominates the transition.

  1. Experimental evaluation of flow-induced noise in level flight of the pigeon (Columba livia).

    PubMed

    Wei, Qingkai; Zhong, Siyang; Huang, Xun

    2013-07-01

    The experimental method employed in an anechoic wind tunnel to characterize flow-induced noise of the pigeon (Columba livia) during level flight is described in this letter. A live pigeon was managed to maintain a steady level flight at the wind tunnel test flow of 15 m/s. A microphone array was fabricated, and the conventional beamforming method was then adopted to yield the corresponding narrowband acoustic images and broadband sound pressure spectral results. The results justified the experimental method developed in this work. It can be seen that the flight noise of the pigeon is mostly from the wing tips. In addition, the spectral waveform of the pigeon flight suggests a slope of -20 dB/dec between 500 Hz and 5 kHz.

  2. Experimental evaluation of flow-induced noise in level flight of the pigeon (Columba livia).

    PubMed

    Wei, Qingkai; Zhong, Siyang; Huang, Xun

    2013-07-01

    The experimental method employed in an anechoic wind tunnel to characterize flow-induced noise of the pigeon (Columba livia) during level flight is described in this letter. A live pigeon was managed to maintain a steady level flight at the wind tunnel test flow of 15 m/s. A microphone array was fabricated, and the conventional beamforming method was then adopted to yield the corresponding narrowband acoustic images and broadband sound pressure spectral results. The results justified the experimental method developed in this work. It can be seen that the flight noise of the pigeon is mostly from the wing tips. In addition, the spectral waveform of the pigeon flight suggests a slope of -20 dB/dec between 500 Hz and 5 kHz. PMID:23862907

  3. Catechin averts experimental diabetes mellitus-induced vascular endothelial structural and functional abnormalities.

    PubMed

    Bhardwaj, Pooja; Khanna, Deepa; Balakumar, Pitchai

    2014-03-01

    Diabetes mellitus is associated with an induction of vascular endothelial dysfunction (VED), an initial event that could lead to the pathogenesis of atherosclerosis and hypertension. Previous studies showed that catechin, a key component of green tea, possesses vascular beneficial effects. We investigated the effect of catechin hydrate in diabetes mellitus-induced experimental vascular endothelial abnormalities (VEA). Streptozotocin (50 mg/kg, i.p., once) administration to rats produced diabetes mellitus, which subsequently induced VEA in 8 weeks by markedly attenuating acetylcholine-induced endothelium-dependent relaxation in the isolated aortic ring preparation, decreasing aortic and serum nitrite/nitrate concentrations and impairing aortic endothelial integrity. These abnormalities in diabetic rats were accompanied with elevated aortic superoxide anion generation and serum lipid peroxidation in addition to hyperglycemia. Catechin hydrate treatment (50 mg/kg/day p.o., 3 weeks) markedly prevented diabetes mellitus-induced VEA and vascular oxidative stress. Intriguingly, in vitro incubation of L-NAME (100 μM), an inhibitor of nitric oxide synthase, or Wortmannin (100 nM), a selective inhibitor of phosphatidylinositol 3-kinase (PI3K), markedly prevented catechin hydrate-induced improvement in acetylcholine-provoked endothelium-dependent relaxation in the diabetic rat aorta. Moreover, catechin hydrate treatment considerably reduced the elevated level of serum glucose in diabetic rats. In conclusion, catechin hydrate treatment prevents diabetes mellitus-induced VED through the activation of endothelial PI3K signal and subsequent activation of eNOS and generation of nitric oxide. In addition, reduction in high glucose, vascular oxidative stress, and lipid peroxidation might additionally contribute to catechin hydrate-associated prevention of diabetic VEA. PMID:24048981

  4. Boehmeria nivea Attenuates the Development of Dextran Sulfate Sodium-Induced Experimental Colitis

    PubMed Central

    Shin, Eun Ju; Sung, Mi Jeong; Yang, Hye Jeong; Kim, Myung Sunny; Hwang, Jin-Taek

    2014-01-01

    We examined the therapeutic effect of an ethanol extract derived from Boehmeria nivea (Linn.) Gaudich in a mouse model of experimental colitis. Treatment with 70% ethanol extract derived from B. nivea (EBN) at a dose of 100, 200, or 500 mg/(kg·d) improved colon shortening, body weight, the disease activity index (DAI), and histopathological score of DSS-induced colitis mice. DSS significantly increased the levels of cyclooxygenase-(COX-) 2 in colon tissue relative to that of the untreated control group. EBN administered at 100, 200, or 500 mg/(kg·d) reduced COX-2 levels in the DSS-treated mice. In addition, EBN decreased the DSS-induced secretion of the inflammatory cytokine interleukin-6 (IL-6) and chemokine monocyte chemotactic protein-1 (MCP-1). Taken together, these data suggest that B. nivea extract is effective in preventing colitis. PMID:25045208

  5. Experimental plan for the investigation of thermally-induced ventilation in atria

    SciTech Connect

    Leung, S.K.; Young, M.F.; Pierson, R.E.

    1981-09-09

    A detailed and logical work plan is outlined for determining if current atrium designs are capable, and to what extent, of thermally inducing ventilation in atria. This passive cooling technique could displace costly refrigerated cooling, ventilation fan energy, and auxiliary space heating. The principal area of interest is for thermally-induced ventilation cooling in commercial and multi-residential buildings. The present work proposes ten test sites for detailed experimental investigation. Six test sites are recommended for detailed quantitative measurements while four are recommended for qualitative examination. These test sites include several atrium designs and span several US climate zones. Measurements planned include: (1) ambient conditions of wind, temperature, humidity and solar radiation; (2) atrium conditions of air flow rates, heat transfer rates, temperature, humidity, internal heat generation, infiltration and HVAC status. A detailed cost plan and test schedule are presented in this work. An optional costing procedure is presented which lists anticipated cost per site rather than a total project cost.

  6. Experimental Study of the Cross Sections of {alpha}-Particle Induced Reactions on 209Bi

    SciTech Connect

    Hermanne, A.; Tarkanyi, F.; Takacs, S.; Szucs, Z.

    2005-05-24

    Alpha particle induced reactions for generation of 211At used in therapeutic nuclear medicine and possible contaminants were investigated with the stacked foil activation technique on natural bismuth targets up to E{alpha}=39 MeV. Excitation functions for the reactions 209Bi({alpha},2n)211At, 209Bi({alpha},3n)210At, 209Bi({alpha},x) 210Po obtained from direct alpha emission measurements and gamma spectra from decay products are compared with earlier literature values. Thick target yields have been deduced from the experimental cross sections.

  7. Experimental characterization and mitigation of turbulence induced signal fades within an ad hoc FSO network.

    PubMed

    Perez, Joaquin; Zvanovec, Stanislav; Ghassemlooy, Zabih; Popoola, Wasiu O

    2014-02-10

    Optical beams propagating through the turbulent atmospheric channel suffer from both the attenuation and phase distortion. Since future wireless networks are envisaged to be deployed in the ad hoc mesh topology, this paper presents the experimental laboratory characterization of mitigation of turbulence induced signal fades for two ad hoc scenarios. Results from measurements of the thermal structure constant along the propagation channels, changes of the coherence lengths for different turbulence regimes and the eye diagrams for partially correlated turbulences in free space optical channels are discussed. Based on these results future deployment of optical ad hoc networks can be more straightforwardly planned.

  8. Experimental investigation of the systematic error on photomechanic methods induced by camera self-heating.

    PubMed

    Ma, Qinwei; Ma, Shaopeng

    2013-03-25

    The systematic error for photomechanic methods caused by self-heating induced image expansion when using a digital camera was systematically studied, and a new physical model to explain the mechanism has been proposed and verified. The experimental results showed that the thermal expansion of the camera outer case and lens mount, instead of mechanical components within the camera, were the main reason for image expansion. The corresponding systematic error for both image analysis and fringe analysis based photomechanic methods were analyzed and measured, then error compensation techniques were proposed and verified.

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

    SciTech Connect

    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, {tau}, ranging from 140 fs to 1 ns. Qualitative differences in the morphology of damage and a departure from the diffusion-dominated {tau}{sup 1/2} scaling indicate that damage results from plasma formation and ablation for {tau}{le}10 ps and from conventional melting and boiling for {tau}>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.

  10. Theoretical and experimental optical studies of cholesteric liquid crystal films with thermally induced pitch gradients.

    PubMed

    Zografopoulos, Dimitrios C; Kriezis, Emmanouil E; Mitov, Michel; Binet, Corinne

    2006-06-01

    The reflection properties of cholesteric films with thermally induced pitch gradients are theoretically and experimentally studied. It is shown that the optical behavior of such films corresponds to the averaged contribution of a number of stochastic pitch variation profiles, due to the transversal and longitudinal nonuniformities that develop in the helical structure of such samples. Depending on the annealing time, both narrow-band and broadband behavior can be selectively achieved. The influence of the pitch profile gradient on the broadband reflection performance of cholesteric samples is theoretically analyzed, and a multi-slab structure for achieving optimum efficiency is proposed.

  11. Nigella sativa amliorates inflammation and demyelination in the experimental autoimmune encephalomyelitis-induced Wistar rats.

    PubMed

    Noor, Neveen A; Fahmy, Heba M; Mohammed, Faten F; Elsayed, Anwar A; Radwan, Nasr M

    2015-01-01

    Multiple sclerosis (MS) is the major, immune-mediated, demyelinating neurodegenerative disease of the central nervous system (CNS). Experimental autoimmune encephalomyelitis (EAE) is a well-established animal model of MS. The aim of the present study was to investigate the protective and ameliorative effects of N. sativa seeds (2.8 g/kg body weight) in EAE-induced Wistar rats. EAE-induced rats were divided into: 1- EAE-induced rats ("EAE" group). 2- "N. sativa + EAE" group received daily oral administration of N. sativa 2 weeks prior EAE induction until the end of the experiment. 3- "EAE + N. sativa" group received daily oral administration of N. sativa after the appearance of first clinical signs until the end of the experiment. All animals were decapitated at the 28th day post EAE-induction. EAE was investigated using histopathological, immunohistochemical and ultrastructural examinations in addition to determination of some oxidative stress parameters in the cerebellum and medulla. N. sativa suppressed inflammation observed in EAE-induced rats. In addition, N. sativa enhanced remyelination in the cerebellum. Moreover, N. sativa reduced the expression of transforming growth factor beta 1 (TGF β1). N. sativa seeds could provide a promising agent effective in both the protection and treatment of EAE.

  12. Nigella sativa amliorates inflammation and demyelination in the experimental autoimmune encephalomyelitis-induced Wistar rats

    PubMed Central

    Noor, Neveen A; Fahmy, Heba M; Mohammed, Faten F; Elsayed, Anwar A; Radwan, Nasr M

    2015-01-01

    Multiple sclerosis (MS) is the major, immune-mediated, demyelinating neurodegenerative disease of the central nervous system (CNS). Experimental autoimmune encephalomyelitis (EAE) is a well-established animal model of MS. The aim of the present study was to investigate the protective and ameliorative effects of N. sativa seeds (2.8 g/kg body weight) in EAE-induced Wistar rats. EAE-induced rats were divided into: 1- EAE-induced rats (“EAE” group). 2- “N. sativa + EAE” group received daily oral administration of N. sativa 2 weeks prior EAE induction until the end of the experiment. 3- “EAE + N. sativa” group received daily oral administration of N. sativa after the appearance of first clinical signs until the end of the experiment. All animals were decapitated at the 28th day post EAE-induction. EAE was investigated using histopathological, immunohistochemical and ultrastructural examinations in addition to determination of some oxidative stress parameters in the cerebellum and medulla. N. sativa suppressed inflammation observed in EAE-induced rats. In addition, N. sativa enhanced remyelination in the cerebellum. Moreover, N. sativa reduced the expression of transforming growth factor beta 1 (TGF β1). N. sativa seeds could provide a promising agent effective in both the protection and treatment of EAE. PMID:26261504

  13. Ameliorative potential of fluoxetine/raloxifene combination on experimentally induced breast cancer.

    PubMed

    Kabel, Ahmed M; Elkhoely, Abeer A

    2016-04-01

    Breast cancer is one of the most common types of malignancies in females worldwide. Targeting the estrogen receptors alone with raloxifene (RAL) reduces the incidence of estrogen receptor positive tumors. Fluoxetine (FLX) is one of selective serotonin reuptake inhibitors that was proven to have anticancer properties. Our aim was to detect the effects of RAL/FLX combination on experimentally induced breast cancer. Eighty female Wistar rats were divided into four equal groups: 7,12-Dimethyl Benzanthracene (DMBA) induced breast cancer group, DMBA+RAL, DMBA+FLX and DMBA+RAL+FLX. Tumor volume, tissue malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6) and transforming growth factor beta1 (TGF-β1) were determined in the tumor tissues. Parts of the tumor were subjected to histopathological examination. RAL or FLX alone or in combination induced significant increase in tumor CAT and SOD with significant decrease in tumor volume, tissue MDA, TNF-α, IL-6 and TGF-β1 and alleviated the histopathological and immunohistochemical changes compared to DMBA group. In conclusion, RAL/FLX combination had a better effect than each of RAL or FLX alone against DMBA-induced breast cancer in rats which may represent a new therapeutic modality for management of breast cancer. PMID:26881735

  14. Bromocriptine induces parapoptosis as the main type of cell death responsible for experimental pituitary tumor shrinkage

    SciTech Connect

    Palmeri, Claudia Mariela Petiti, Juan Pablo; Valle Sosa, Liliana del; Gutierrez, Silvina; Paul, Ana Lucia de; Mukdsi, Jorge Humberto; Torres, Alicia Ines

    2009-10-01

    Bromocriptine (Bc) produces pituitary tumoral mass regression which induces the cellular death that was classically described as apoptosis. However, recent works have related that other mechanisms of cell death could also be involved in the maintenance of physiological and pathological pituitary homeostasis. The aim of this study was to evaluate and characterize the different types of cell death in the involution induced by Bc in experimental rat pituitary tumors. The current study demonstrated that Bc induced an effective regression of estrogen induced pituitary tumors by a mechanism identified as parapoptosis. This alternative cell death was ultrastructurally recognized by extensive cytoplasmic vacuolization and an increased cell electron density, represented around 25% of the total pituitary cells counted. Furthermore, the results obtained from biochemical assays did not correspond to the criteria of apoptosis or necrosis. We also investigated the participation of p38, ERK1/2 and PKC{delta} in the parapoptotic pathway. An important observation was the significant increase in phosphorylated forms of these MAPKs, the holoenzyme and catalytic fragments of PKC{delta} in nuclear fractions after Bc administration compared to control and estrogen treated rats. Furthermore, the immunolocalization at ultrastructural level of these kinases showed a similar distribution pattern, with a prevalent localization at nuclear level in lactotrophs from Bc treated rats. In summary, we determined that parapoptosis is the predominant cell death type involved in the regression of pituitary tumors in response to Bc treatment, and may cause the activation of PKC{delta}, ERK1/2 and p38.

  15. The Effects of Experimentally Induced Low Back Pain on Spine Rotational Stiffness and Local Dynamic Stability.

    PubMed

    Ross, Gwyneth B; Mavor, Matthew; Brown, Stephen H M; Graham, Ryan B

    2015-09-01

    Local dynamic stability, quantified using the maximum finite-time Lyapunov exponent (λ max), and the muscular contributions to spine rotational stiffness can provide pertinent information regarding the neuromuscular control of the spine during movement tasks. The primary goal of the present study was to assess if experimental capsaicin-induced low back pain (LBP) affects spine stability and the neuromuscular control of repetitive trunk movements in a group of healthy participants with no history of LBP. Fourteen healthy males were recruited for this investigation. Each participant was asked to complete three trials (baseline, in pain, and recovery) of 35 cycles of a repetitive trunk flexion/extension task at a rate of 0.25 Hz. Local dynamic stability and the muscular contributions to lumbar spine rotational stiffness were significantly impaired during the LBP trial compared to the baseline trial (p < 0.05); however, there was a trend for these measures to recover after a 1 h rest. This study provides evidence that capsaicin can effectively induce LBP, thereby altering spine rotational stiffness and local dynamic stability. Future research should directly compare the effects capsaicin-induced LBP and intramuscular/intraligamentous induced LBP on these same variables.

  16. A proposal for the experimental detection of CSL induced random walk

    PubMed Central

    Bera, Sayantani; Motwani, Bhawna; Singh, Tejinder P.; Ulbricht, Hendrik

    2015-01-01

    Continuous Spontaneous Localization (CSL) is one possible explanation for dynamically induced collapse of the wave-function during a quantum measurement. The collapse is mediated by a stochastic non-linear modification of the Schrödinger equation. A consequence of the CSL mechanism is an extremely tiny violation of energy-momentum conservation, which can, in principle, be detected in the laboratory via the random diffusion of a particle induced by the stochastic collapse mechanism. In a paper in 2003, Collett and Pearle investigated the translational CSL diffusion of a sphere, and the rotational CSL diffusion of a disc, and showed that this effect dominates over the ambient environmental noise at low temperatures and extremely low pressures (about ten-thousandth of a pico-Torr). In the present paper, we revisit their analysis and argue that this stringent condition on pressure can be relaxed, and that the CSL effect can be seen at the pressure of about a pico-Torr. A similar analysis is provided for diffusion produced by gravity-induced decoherence, where the effect is typically much weaker than CSL. We also discuss the CSL induced random displacement of a quantum oscillator. Lastly, we propose possible experimental set-ups justifying that CSL diffusion is indeed measurable with the current technology. PMID:25563619

  17. Hypolipidemic Effect of Celastrus paniculatus in Experimentally Induced Hypercholesterolemic Wistar Rats

    PubMed Central

    Prakash, K.; Maheshwari, V. L.

    2010-01-01

    The objective of the present study was to evaluate hypolipidemic effect of methanolic extract of Celastrus paniculatus in experimentally induced hypercholesterolemic rats. Hypercholesterolemia was induced by feeding the animals with high fat diet. Oral administration of methanolic seed extract (50%) of Celastrus paniculatus at the optimized dose of 65 mg/kg body weight, substantially reduced the plasma total cholesterol, triglycerides and LDL cholesterol in comparison with induced hypercholesterolemic animal group and the results were comparable with the standard hypocholesterolemic drug and almost similar to the control group. Atherogenic index and liver weight of treated animals also showed significant decrease compared to the hypercholesterolemic animals. It substantially increased the HDL cholesterol level as compared to control group. A significant increase in the activities of lipoprotein lipase and plasma LCAT enhanced hepatic bile acid synthesis and thereby, increased degradation of cholesterol to neutral sterols. Furthermore, the activities of HMG-CoA reductase, glucose 6-phosphate dehydrogenase and malate dehydrogenase were significantly reduced. Histological studies showed less cholesterol deposits in the aorta of animals fed with seed extract of C. paniculatus compared to the induced hypercholesterolemic animals not given C. paniculatus supplement. PMID:21966115

  18. A proposal for the experimental detection of CSL induced random walk.

    PubMed

    Bera, Sayantani; Motwani, Bhawna; Singh, Tejinder P; Ulbricht, Hendrik

    2015-01-01

    Continuous Spontaneous Localization (CSL) is one possible explanation for dynamically induced collapse of the wave-function during a quantum measurement. The collapse is mediated by a stochastic non-linear modification of the Schrödinger equation. A consequence of the CSL mechanism is an extremely tiny violation of energy-momentum conservation, which can, in principle, be detected in the laboratory via the random diffusion of a particle induced by the stochastic collapse mechanism. In a paper in 2003, Collett and Pearle investigated the translational CSL diffusion of a sphere, and the rotational CSL diffusion of a disc, and showed that this effect dominates over the ambient environmental noise at low temperatures and extremely low pressures (about ten-thousandth of a pico-Torr). In the present paper, we revisit their analysis and argue that this stringent condition on pressure can be relaxed, and that the CSL effect can be seen at the pressure of about a pico-Torr. A similar analysis is provided for diffusion produced by gravity-induced decoherence, where the effect is typically much weaker than CSL. We also discuss the CSL induced random displacement of a quantum oscillator. Lastly, we propose possible experimental set-ups justifying that CSL diffusion is indeed measurable with the current technology. PMID:25563619

  19. PROTECTIVE EFFECT OF HESPERIDIN ON CARDIOVASCULAR COMPLICATION IN EXPERIMENTALLY INDUCED MYOCARDIAL INFARCTION IN DIABETES IN RATS

    PubMed Central

    Kakadiya, Jagdish; Mulani, Haresh; Shah, Nehal

    2010-01-01

    Present study was designed to evaluate effect Hesperidin on Cardiovascular Complication in isoproterenol induced myocardial infarction in normal and Streptozotocin-Nicotinamide induced in diabetic rats. Hesperidin (100 mg/kg, p.o) was administered for 28 days in rats injected with single dose of Streptozotocin (65 mg/kg, i.p, STZ) and Nicotinamide (110 mg/kg, i.p, NIC) and after isoproterenol (200 mg/kg, s.c.) induced myocardial infarction in rats on 29th and 30th day. At the end of experimental period (i.e. on the day 31) serum and heart tissues sample were collected, and glucose, HbA1c and Total Cholesterol (TC), Triglycerides (TG) and High density lipoprotein (HDL) and cholesterol ester synthetase (CES), lecithin Cholesterol acyl transferase (LCAT), lipoprotein lipase (LPL), systolic and diastolic blood pressure were find out. Administration of STZ–NIC in rats showed a significant (p<0.001) increased in the levels of serum glucose, glycosylated heamoglobin (HbA1c), Total Cholesterol (TC), Triglycerides (TG) and Low density lipoprotein (LDL) whereas the levels of High density lipoprotein (HDL) were found to be non significant but significant (p<0.001) increased in the level of heart tissues CES and significant (p<0.001, p<0.01) decreased LCAT and LPL, significantly (p<0.01) increased systolic and diastolic blood pressure as compared to respective control groups. Treatment with Hesperidin significantly (P<0.05) decreased HbA1c, glucose, CES level and significantly (P<0.01) decreased LDL, TC, TG, systolic and diastolic blood pressure and significant (P<0.01) increased LCAT and LPL level but no significantly change HDL in compared to diabetic control group. We concluded that HES (100 mg/kg) is effective in controlling blood glucose levels and reduced cardiac complication in experimentally induced myocardial infarction diabetic rats. PMID:24825971

  20. Protective effect of hesperidin on cardiovascular complication in experimentally induced myocardial infarction in diabetes in rats.

    PubMed

    Kakadiya, Jagdish; Mulani, Haresh; Shah, Nehal

    2010-03-01

    Present study was designed to evaluate effect Hesperidin on Cardiovascular Complication in isoproterenol induced myocardial infarction in normal and Streptozotocin-Nicotinamide induced in diabetic rats. Hesperidin (100 mg/kg, p.o) was administered for 28 days in rats injected with single dose of Streptozotocin (65 mg/kg, i.p, STZ) and Nicotinamide (110 mg/kg, i.p, NIC) and after isoproterenol (200 mg/kg, s.c.) induced myocardial infarction in rats on 29(th) and 30(th) day. At the end of experimental period (i.e. on the day 31) serum and heart tissues sample were collected, and glucose, HbA1c and Total Cholesterol (TC), Triglycerides (TG) and High density lipoprotein (HDL) and cholesterol ester synthetase (CES), lecithin Cholesterol acyl transferase (LCAT), lipoprotein lipase (LPL), systolic and diastolic blood pressure were find out. Administration of STZ-NIC in rats showed a significant (p<0.001) increased in the levels of serum glucose, glycosylated heamoglobin (HbA1c), Total Cholesterol (TC), Triglycerides (TG) and Low density lipoprotein (LDL) whereas the levels of High density lipoprotein (HDL) were found to be non significant but significant (p<0.001) increased in the level of heart tissues CES and significant (p<0.001, p<0.01) decreased LCAT and LPL, significantly (p<0.01) increased systolic and diastolic blood pressure as compared to respective control groups. Treatment with Hesperidin significantly (P<0.05) decreased HbA1c, glucose, CES level and significantly (P<0.01) decreased LDL, TC, TG, systolic and diastolic blood pressure and significant (P<0.01) increased LCAT and LPL level but no significantly change HDL in compared to diabetic control group. We concluded that HES (100 mg/kg) is effective in controlling blood glucose levels and reduced cardiac complication in experimentally induced myocardial infarction diabetic rats.

  1. Aerobic exercise training without weight loss reduces dyspnea on exertion in obese women.

    PubMed

    Bernhardt, Vipa; Stickford, Jonathon L; Bhammar, Dharini M; Babb, Tony G

    2016-01-15

    Dyspnea on exertion (DOE) is a common symptom in obesity. We investigated whether aerobic exercise training without weight loss could reduce DOE. Twenty-two otherwise healthy obese women participated in a 12-week supervised aerobic exercise training program, exercising 30 min/day at 70-80% heart rate reserve, 4 days/week. Subjects were grouped based on their Ratings of Perceived Breathlessness (RPB) during constant load 60 W cycling: +DOE (n=12, RPB≥4, 37±7 years, 34±4 kg/m(2)) and -DOE (n=10, RPB≤2, 32±6 years, 33±3 kg/m(2)). No significant differences between the groups in body composition, pulmonary function, or cardiorespiratory fitness were observed pre-training. Post-training,peak was improved significantly in both groups (+DOE: 12±7, -DOE: 14±8%). RPB was significantly decreased in the +DOE (4.7±1.0-2.5±1.0) and remained low in the -DOE group (1.2±0.6-1.3±1.0) (interaction p<0.001). The reduction in RPB was not significantly correlated with the improvement in cardiorespiratory fitness. Aerobic exercise training improved cardiorespiratory fitness and DOE and thus appears to be an effective treatment for DOE in obese women.

  2. Belching, regurgitation, chest tightness and dyspnea: not gastroesophageal reflux disease but asthma.

    PubMed

    Zhang, Jing-Xi; Zhan, Xian-Bao; Bai, Chong; Li, Qiang

    2015-02-01

    Belching is a common symptom of gastroesophageal reflux disease. If the symptoms are not relieved after anti-reflux treatment, another etiology should be considered. Here, we report a case of a 43-year-old man who presented with belching, regurgitation, chest tightness and dyspnea for 18 mo, which became gradually more severe. Gastroscopic examination suggested superficial gastritis. Twenty-four-hour esophageal pH monitoring showed that the Demeester score was 11.4, in the normal range. High-resolution manometry showed that integrated relaxation pressure and intrabolus pressure were higher than normal (20 mmHg and 22.4 mmHg, respectively), indicating gastroesophageal junction outflow tract obstruction. Pulmonary function test showed severe obstructive ventilation dysfunction [forced expiratory volume in 1 second (FEV1)/forced vital capacity 32%, FEV1 was 1.21 L, occupying 35% predicted value after salbuterol inhalation], and positive bronchial dilation test (∆FEV1 260 mL, ∆FEV1% 27%). Skin prick test showed Dermatophagoides farinae (++), house dust mite (++++), and shrimp protein (++). Fractional exhaled nitric oxide measurement was 76 ppb. All the symptoms were alleviated completely and pulmonary function increased after combination therapy with corticosteroids and long-acting β2-agonist. Bronchial asthma was eventually diagnosed by laboratory tests and the effect of anti-asthmatic treatment, therefore, physicians, especially the Gastrointestinal physicians, should pay attention to the belching symptoms of asthma.

  3. Dyspnea and dysphagia from upper airway obstruction after occipitocervical fusion in the pediatric age group.

    PubMed

    Huang, Meng; Gonda, David D; Briceño, Valentina; Lam, Sandi K; Luerssen, Thomas G; Jea, Andrew

    2015-04-01

    Upper airway obstruction resulting from overflexion of the craniocervical junction after occipitocervical fusion is a rare but potentially life-threatening complication and is associated with morbidity. The authors retrospectively reviewed the medical records and diagnostic images of 2 pediatric patients who underwent occipitocervical fusion by the Neuro-Spine Program at Texas Children's Hospital and experienced dyspnea and/or dysphagia from new upper airway obstruction in the postoperative period. Patient demographics, operative data, and preoperative and postoperative occiput-C2 angles were recorded. A review of the literature for similar complications after occipitocervical fusion was performed. A total of 13 cases of prolonged upper airway obstruction after occipitocervical fusion were analyzed. Most of these cases involved adults with rheumatoid arthritis. To the best of the authors' knowledge, there have been no previous reports of prolonged upper airway obstruction in children after an occipitocervical fusion. Fixation of the neck in increased flexion (-18° to -5°) was a common finding among these adult and pediatric cases. The authors' cases involved children with micrognathia and comparatively large tongues, which may predispose the oropharynx to obstruction with even the slightest amount of increased flexion. Close attention to a satisfactory fixation angle (occiput-C2 angle) is necessary to avoid airway obstruction after an occipitocervical fusion. Children with micrognathia are particularly sensitive to changes in flexion at the craniocervical junction after occipitocervical fixation. PMID:25828489

  4. [Case of pollinosis to grass pollens who presented with dyspnea successfully treated by rush immunotherapy].

    PubMed

    Kawada, Yasusuke; Takamasu, Tetsuya; Inuo, Chisato; Aikawa, Hiroyuki; Kurihara, Kazuyuki

    2007-11-01

    We present a 15 years old boy who experienced unusual symptoms for pollen allergy, and successfully treated by rush immunotherapy. The patient started to complain erythema and edema on his face and serous rhinorrhea at 10 years old when going out. He entered baseball team at junior high school, and subsequently experienced choking sensation, dyspnea, face edema, and it was sometimes impossible to continue play. He was diagnosed as bronchial asthma at some hospital, and prescribed many anti-asthma medications including inhaled corticosteroid, which did not take effect. His symptoms deteriorated in summer and ameliorated in winter. When he was 15 years old, he was referred to us by a pediatrician for reassessment of his symptoms. Flow-volume curve was normal, and bronchial provocation test (acetylcholine and histamine), and exercise challenge were negative. IgE antibodies specific to grass pollens were highly positive. We made a diagnosis of pollinosis to grass pollens instead of bronchial asthma. Oral antihistamines and intranasal corticosteroid partially improved his symptoms. We started rush-immunotherapy of grass-pollens (oats and bromegrass), Japanese cedar, and ragweed. His symptoms improved dramatically on the next season of grass pollens.

  5. A Computational and Experimental Study of Nonlinear Aspects of Induced Drag

    NASA Technical Reports Server (NTRS)

    Smith, Stephen C.

    1996-01-01

    performance of the split-tip wing was also investigated by wing tunnel experiments. Induced drag was determined from force measurements by subtracting the estimated viscous drag, and from an analytical drag-decomposition method using a wake survey. The experimental results confirm the computational prediction.

  6. Antihepatotoxic nature of Ulva reticulata (Chlorophyceae) on acetaminophen-induced hepatoxicity in experimental rats.

    PubMed

    Balaji Raghavendra Rao, H; Sathivel, A; Devaki, T

    2004-01-01

    Ulva reticulata, a marine edible green alga, is a known source of proteins, vitamins, and sulfated polysaccharides. Though there are many reports in the literature regarding the composition and antiviral property of Ulva sp., studies of the antihepatotoxic property of green seaweeds in animal model are scarce. We have studied the antihepatotoxic nature of this marine green edible alga, U. reticulata, in a hot water extract (150 mg/kg of body weight for a period of 15 days) against acetaminophen- induced hepatotoxicity in experimental albino rats. The acetaminophen-induced rats showed significant elevation in levels of the serum marker enzymes aspartate transaminase and alanine transaminase and of lipid peroxides in liver tissue with decreased levels of antioxidant enzymes such as superoxide dismutase and catalase. The levels of reduced glutathione and vitamins (E and C) were also decreased in the liver tissue of acetaminophen-intoxicated rats. The oral pretreatment with a hot water extract of U. reticulata reduced the hepatotoxicity triggered by acetaminophen considerably by improving the antioxidant status in experimental animals with depleted levels of lipid peroxides. These results indicate that the oral pretreatment with a hot water extract of U. reticulata in rats is effective in reducing the hepatic oxidative stress via free radical scavenging properties, suggesting an antihepatotoxic activity. PMID:15671697

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

    PubMed

    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.

  8. Brugia malayi abundant larval transcript 2 protein treatment attenuates experimentally-induced colitis in mice.

    PubMed

    Khatri, Vishal; Amdare, Nitin; Yadav, Ravi Shankar; Tarnekar, Aaditya; Goswami, Kalyan; Reddy, Maryada Venkata Rami

    2015-11-01

    Helminths are known to modulate host's immunity by suppressing host protective pro-inflammatory responses. Such immunomodulatory effects have been experimentally shown to have therapeutic implications in immune mediated disorders. In the present study, we have explored a filarial protein i.e. Brugia malayi recombinant abundant larval transcript 2 (rBmALT2) for its therapeutic effect in dextran sodium sulfate (DSS) induced colitis in mouse model. The immunomodulatory activity of rBmALT-2 was initially confirmed by demonstrating that it suppressed the lipopolysaccharide (LPS) induced nitric oxide synthesis and down-regulated the expression of pro-inflammatory cytokines in vitro by peritoneal exudate cells of mice. Treatment with rBmALT2 reduced severity of colitis associated with significant reduction in weight loss, disease activity, colon damage, mucosal edema and histopathological score including myeloperoxidase activity in colon tissues. rBmALT2 was comparatively more effective in attenuation of colitis when used in the preventive mode than when used for curative purpose. The therapeutic effect of rBmALT2 was found to be associated with downregulation of IFN-γ, IL-6, IL-17 and upregulation of IL-10 cytokines. These results provide strong experimental evidence that BmALT2 could be a potential alternative therapeutic agent in colitis. PMID:26669016

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

    NASA Astrophysics Data System (ADS)

    Jaiswal, S.; Bandyopadhyay, P.; Sen, A.

    2016-08-01

    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.

  10. Expression of Sonic hedgehog and retinal opsin genes in experimentally-induced myopic chick eyes.

    PubMed

    Escaño, M F; Fujii, S; Sekiya, Y; Yamamoto, M; Negi, A

    2000-11-01

    The purpose of this study was to evaluate changes in the expression of different genes in chick retinal tissues after induction of experimental myopia and to evaluate the roles of these genes in the regulation of postnatal eye growth and myopia. Form-deprivation using occlusive goggles and hyperopic defocus by negative spectacle lenses were used to induce myopia in hatched chicks. Expression levels of Sonic hedgehog, its receptor complex, and other retinal cell genes were evaluated by semi-quantitative reverse transcription-polymerase chain reaction. Levels of Sonic hedgehog protein were further evaluated by Western blot analysis. The induction of myopia caused significant increase in expression of Sonic hedgehog mRNA and protein and increased expression of blue and red opsin mRNA. In contrast, the expression of mRNA for Sonic hedgehog receptor complex (Patched-Smoothened), rhodopsin, vimentin, green opsin, violet opsin, and HPC-1 were unaffected by the induction of myopia. The increase in expression of Sonic hedgehog in chick retinas in experimentally-induced myopia suggests involvement in the retina control of postnatal eye growth. Furthermore, Sonic hedgehog may influence the expression of blue and red opsins under myopic conditions.

  11. Numerical and experimental investigation of natural flow-induced vibrations of flexible hydrofoils

    NASA Astrophysics Data System (ADS)

    Chae, Eun Jung; Akcabay, Deniz Tolga; Lelong, Alexandra; Astolfi, Jacques Andre; Young, Yin Lu

    2016-07-01

    The objective of this work is to present combined numerical and experimental studies of natural flow-induced vibrations of flexible hydrofoils. The focus is on identifying the dependence of the foil's vibration frequencies and damping characteristics on the inflow velocity, angle of attack, and solid-to-fluid added mass ratio. Experimental results are shown for a cantilevered polyacetate (POM) hydrofoil tested in the cavitation tunnel at the French Naval Academy Research Institute (IRENav). The foil is observed to primarily behave as a chordwise rigid body and undergoes spanwise bending and twisting deformations, and the flow is observed to be effectively two-dimensional (2D) because of the strong lift retention at the free tip caused by a small gap with a thickness less than the wall boundary layer. Hence, the viscous fluid-structure interaction (FSI) model is formulated by coupling a 2D unsteady Reynolds-averaged Navier-Stokes (URANS) model with a two degree-of-freedom (2-DOF) model representing the spanwise tip bending and twisting deformations. Good agreements were observed between viscous FSI predictions and experimental measurements of natural flow-induced vibrations in fully turbulent and attached flow conditions. The foil vibrations were found to be dominated by the natural frequencies in absence of large scale vortex shedding due to flow separation. The natural frequencies and fluid damping coefficients were found to vary with velocity, angle of attack, and solid-to-fluid added mass ratio. In addition, the numerical results showed that the in-water to in-air natural frequency ratios decreased rapidly, and the fluid damping coefficients increased rapidly, as the solid-to-fluid added mass ratio decreases. Uncoupled mode (UM) linear potential theory was found to significantly over-predict the fluid damping for cases of lightweight flexible hydrofoils, and this over-prediction increased with higher velocity and lower solid-to-fluid added mass ratio.

  12. Experimental tonic hand pain modulates the corticospinal plasticity induced by a subsequent hand deafferentation.

    PubMed

    Mavromatis, N; Gagné, M; Voisin, J I A V; Reilly, K T; Mercier, C

    2016-08-25

    Sensorimotor reorganization is believed to play an important role in the development and maintenance of phantom limb pain, but pain itself might modulate sensorimotor plasticity induced by deafferentation. Clinical and basic research support this idea, as pain prior to amputation increases the risk of developing post-amputation pain. The aim of this study was to examine the influence of experimental tonic cutaneous hand pain on the plasticity induced by temporary ischemic hand deafferentation. Sixteen healthy subjects participated in two experimental sessions (Pain, No Pain) in which transcranial magnetic stimulation was used to assess corticospinal excitability in two forearm muscles (flexor carpi radialis and flexor digitorum superficialis) before (T0, T10, T20, and T40) and after (T60 and T75) inflation of a cuff around the wrist. The cuff was inflated at T45 in both sessions and in the Pain session capsaicin cream was applied on the dorsum of the hand at T5. Corticospinal excitability was significantly greater during the Post-inflation phase (p=0.002) and increased similarly in both muscles (p=0.861). Importantly, the excitability increase in the Post-inflation phase was greater for the Pain than the No-Pain condition (p=0.006). Post-hoc analyses revealed a significant difference between the two conditions during the Post-inflation phase (p=0.030) but no difference during the Pre-inflation phase (p=0.601). In other words, the corticospinal facilitation was greater when pain was present prior to cuff inflation. These results indicate that pain can modulate the plasticity induced by another event, and could partially explain the sensorimotor reorganization often reported in chronic pain populations. PMID:27291642

  13. Assessing potential abiotic and biotic complications of crayfish-induced gravel transport in experimental streams

    NASA Astrophysics Data System (ADS)

    Statzner, Bernhard; Peltret, Odile

    2006-03-01

    Biogeomorphology adds the element "biological dynamics" (of populations or communities) to chemical and physical geomorphic factors and thus complicates the framework of geomorphic processes. Such biological complications of the animal-induced transport of solids in streams should be particularly important in crayfish, as crayfish affect this transport through their overall activity and intraspecific aggression levels, which could be modified by shelter availability or the establishment of dominance hierarchies among individuals not knowing each other. Using experimental streams, we tested these hypotheses by measuring how shelter availability or residential crayfish group invasion by unknown individuals affected the impact of the crayfish Orconectes limosus on the (i) transport of gravel at baseflow (during 12 experimental days); (ii) sediment surface characteristics (after 12 days); and (iii) critical shear stress causing incipient gravel motion during simulated floods (after 12 days). The two potentially important factors shelter availability or residential group invasion negligibly affected the crayfish impact on gravel sediments, suggesting that habitat unfamiliarity (a third potentially important factor affecting crayfish activity) should increase the crayfish-induced sediment transport. Because habitat unfamiliarity is associated with sporadic long-distance migrations of a few crayfish individuals, this third factor should play a minor role in real streams, where crayfish biomass should be a key factor in relations with crayfish effects on sediments. Therefore, we combined the results of this study with those of previous crayfish experiments to assess how crayfish biomass could serve in modelling the gravel transport. Crayfish biomass explained 47% of the variability in the baseflow gravel transport and, in combination with the coefficient of variation of the bed elevation and algal cover, 72% of the variability in the critical gravel shear stress. These

  14. Morphological and cellular examinations of experimentally induced malocclusion in mice mandibular condyle.

    PubMed

    Jung, Jae-Kwang; Sohn, Wern-Joo; Lee, Youngkyun; Bae, Yong Chul; Choi, Jae-Kap; Kim, Jae-Young

    2014-02-01

    Occlusal alignment is known clinically to have a widespread influence on the stomatognathic system, including the temporomandibular joint and masticatory muscles. However, while occlusion is still an important determinant of most dental treatments, the exact effect of occlusal alignment is unclear because of a lack of conclusive scientific evidence. In this study, a malocclusion model system is used to examine the cellular and histologic alterations in the contralateral condyle of mice after a malocclusion was induced by a build-up of resin on the left maxillary molars. A significant decrease in the thickness of the condylar cartilage was found in the 1-week experimental group, together with increased apoptosis and decreased proliferation in the condylar head, which included cartilage and subchondral bone. Additionally, the number of TRAP-positive osteoclasts and MPO- and F4/80-positive inflammatory cells in the subchondral bone were significantly higher in the 1-week experimental group. Unbalanced malocclusion caused increased bone remodeling, as evidenced by increased osteoclastic activity and inflammatory responses (macrophages and neutrophils, respectively). However, these alterations in the 1-week experimental group were subsequently attenuated and restored almost to the baseline at 3 weeks after the induction of the malocclusion.

  15. Radiating plasma species density distribution in EUV-induced plasma in argon: a spatiotemporal experimental study

    NASA Astrophysics Data System (ADS)

    van der Horst, R. M.; Beckers, J.; Osorio, E. A.; van de Ven, T. H. M.; Banine, V. Y.

    2015-12-01

    In this contribution we experimentally study temporally and spatially resolved radiating plasma species density distribution in plasma induced by irradiating a low pressure argon gas with high energy photons with a wavelength of 13.5 nm, i.e. extreme ultraviolet (EUV). This is done by recording the optical emission spatially and temporally resolved by an iCCD camera as a function of the argon gas pressure. Our experimental results show that the emission intensity, i.e. density of radiating plasma species, depends quadratically on the gas pressure. The linear term is due to photoionization and simultaneous excitation by EUV photons, the quadratic term due to electron impact excitation by electrons generated by photoionization. The decay of radiating plasma species can be divided into two phases. At time scales shorter than 10 μs (first phase), the decay is governed by radiative decay of radiating plasma species. At longer time scales (second phase, >10 μs), the decay is dominated by diffusion and subsequent de-excitation at the wall. The experimental decay and expansion during this phase corresponds well with a simplified diffusion model. In order to gain more insight in this exotic type of plasma, we compare the electron density from previous measurements with the results obtained here.

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

    PubMed Central

    Mohd Sairazi, Nur Shafika; Sirajudeen, K. N. S.; Asari, Mohd Asnizam; Muzaimi, Mustapha; Mummedy, Swamy; Sulaiman, Siti Amrah

    2015-01-01

    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. PMID:26793262

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

    PubMed Central

    Tufiño, Cecilia; Villanueva-López, Cleva; Ibarra-Barajas, Maximiliano; Bracho-Valdés, Ismael; Bobadilla-Lugo, Rosa Amalia

    2014-01-01

    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. PMID:25610861

  18. Evaluation of anti-urolithiatic activity of Pashanabhedadi Ghrita against experimentally induced renal calculi in rats.

    PubMed

    Gupta, Sanjay Kumar; Baghel, Madhav Singh; Bhuyan, Chaturbhuja; Ravishankar, B; Ashok, B K; Patil, Panchakshari D

    2012-07-01

    Population in an industrialized world is afflicted by urinary stone disease. Kidney stones are common in all kinds of urolithiasis. One distinguished formulation mentioned by Sushruta for management of Ashmari (urolithiasis) is Pashanabhedadi Ghrita (PBG), which is in clinical practice since centuries. Validation of drug is the requirement of time through the experimental study. In this study, trial of PBG has been made against ammonium oxalate rich diet and gentamicin injection induced renal calculi in albino rats. The calculi were induced by gentamicin injection and ammonium oxalate rich diet. Test drug was administered concomitantly in the dose of 900 mg/kg for 15 consecutive days. Rats were sacrificed on the 16(th) day. Parameters like kidney weight, serum biochemical, kidney tissue and histopathology of kidney were studied. Concomitant treatment of PBG attenuates blood biochemical parameters non-significantly, where as it significantly attenuated lipid peroxidation and enhanced glutathione and glutathione peroxidase activities. It also decreased crystal deposition markedly into the renal tubules in number as well as size and prevented damage to the renal tubules. The findings showed that PBG is having significant anti-urolithiatic activities against ammonium oxalate rich diet plus gentamicine injection induced urolithiasis in rats. PMID:23723654

  19. Evaluation of anti-urolithiatic activity of Pashanabhedadi Ghrita against experimentally induced renal calculi in rats

    PubMed Central

    Gupta, Sanjay Kumar; Baghel, Madhav Singh; Bhuyan, Chaturbhuja; Ravishankar, B.; Ashok, B. K.; Patil, Panchakshari D.

    2012-01-01

    Population in an industrialized world is afflicted by urinary stone disease. Kidney stones are common in all kinds of urolithiasis. One distinguished formulation mentioned by Sushruta for management of Ashmari (urolithiasis) is Pashanabhedadi Ghrita (PBG), which is in clinical practice since centuries. Validation of drug is the requirement of time through the experimental study. In this study, trial of PBG has been made against ammonium oxalate rich diet and gentamicin injection induced renal calculi in albino rats. The calculi were induced by gentamicin injection and ammonium oxalate rich diet. Test drug was administered concomitantly in the dose of 900 mg/kg for 15 consecutive days. Rats were sacrificed on the 16th day. Parameters like kidney weight, serum biochemical, kidney tissue and histopathology of kidney were studied. Concomitant treatment of PBG attenuates blood biochemical parameters non-significantly, where as it significantly attenuated lipid peroxidation and enhanced glutathione and glutathione peroxidase activities. It also decreased crystal deposition markedly into the renal tubules in number as well as size and prevented damage to the renal tubules. The findings showed that PBG is having significant anti-urolithiatic activities against ammonium oxalate rich diet plus gentamicine injection induced urolithiasis in rats. PMID:23723654

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

    PubMed

    Mohd Sairazi, Nur Shafika; Sirajudeen, K N S; Asari, Mohd Asnizam; Muzaimi, Mustapha; Mummedy, Swamy; Sulaiman, Siti Amrah

    2015-01-01

    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.

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

    SciTech Connect

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

    1990-08-01

    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.

  2. Effects of Schizolobium parahyba Extract on Experimental Bothrops Venom-Induced Acute Kidney Injury

    PubMed Central

    Martines, Monique Silva; Mendes, Mirian M.; Shimizu, Maria H. M.; Melo Rodrigues, Veridiana; de Castro, Isac; Filho, Sebastião R. Ferreira; Malheiros, Denise M. A. C.; Yu, Luis; Burdmann, Emmanuel A.

    2014-01-01

    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. PMID:24551041

  3. Diet shifts and population dynamics of estuarine foraminifera during ecosystem recovery after experimentally induced hypoxia crises

    NASA Astrophysics Data System (ADS)

    Brouwer, G. M.; Duijnstee, I. A. P.; Hazeleger, J. H.; Rossi, F.; Lourens, L. J.; Middelburg, J. J.; Wolthers, M.

    2016-03-01

    This study shows foraminiferal dynamics after experimentally induced hypoxia within the wider context of ecosystem recovery. 13C-labeled bicarbonate and glucose were added to the sediments to examine foraminiferal diet shifts during ecosystem recovery and test-size measurements were used to deduce population dynamics. Hypoxia-treated and undisturbed patches were compared to distinguish natural (seasonal) fluctuations from hypoxia-induced responses. The effect of timing of disturbance and duration of recovery were investigated. The foraminiferal diets and population dynamics showed higher fluctuations in the recovering patches compared to the controls. The foraminiferal diet and population structure of Haynesina germanica and Ammonia beccarii responded differentially and generally inversely to progressive stages of ecosystem recovery. Tracer inferred diet estimates in April and June and the two distinctly visible cohorts in the test-size distribution, discussed to reflect reproduction in June, strongly suggest that the ample availability of diatoms during the first month of ecosystem recovery after the winter hypoxia was likely profitable to A. beccarii. Enhanced reproduction itself was strongly linked to the subsequent dietary shift to bacteria. The distribution of the test dimensions of H. germanica indicated that this species had less fluctuation in population structure during ecosystem recovery but possibly reproduced in response to the induced winter hypoxia. Bacteria seemed to consistently contribute more to the diet of H. germanica than diatoms. For the diet and test-size distribution of both species, the timing of disturbance seemed to have a higher impact than the duration of the subsequent recovery period.

  4. The effect of local deep microwave hyperthermia on experimental zymosan-induced arthritis in rabbits.

    PubMed

    Weinberger, A; Abramonvici, A; Fadila, R; Levy, A; Giler, S; Lev, A

    1990-10-01

    The effect of local deep microwave hyperthermia (LDMWH) on normal and Zymosan-induced arthritis has been evaluated in 12 rabbits (24 joints). LDMWH, four treatments to each joint (twice weekly for a period of 2 wk), was generated by an antenna operating at 915 MHz for 60 min, reaching an intraarticular temperature of 42.5 +/- 0.5 degrees C. A surface cooling system was used with the microwave apparatus. Two weeks after the last treatment, all animals were sacrificed. The application of LDMWH on normal joints induced a limited proliferation of the synovial lining cells with a minimal perivascular infiltration of mononuclear and neutrophil cells. However, no histologic damage to the skin, muscles, bone, cartilage or bone marrow adjacent to the heated joints could be noted. Induction of Zymosan arthritis (2 wk before LDMWH) was characterized by pannus formation and granulomatous reaction accompanied by fibrinoid deposits and disseminated necrotic foci in the synovial intima. The LDMWH treatment on the examined arthritic joints brought about a reduction in the degree of granulomatous reaction concomitant with the appearance of some fibrocytes and fine collagen fibrils. These findings suggest that LDMWH can be safely applied, even repeatedly, without morphologic evidence of damage to any normal mesenchymal tissue. Moreover, it reduces the inflammatory process in experimentally induced synovitis.

  5. Fumigaclavine C ameliorates dextran sulfate sodium-induced murine experimental colitis via NLRP3 inflammasome inhibition.

    PubMed

    Guo, Wenjie; Hu, Shasha; Elgehama, Ahmed; Shao, Fenli; Ren, Ren; Liu, Wen; Zhang, Wenjing; Wang, Xinlei; Tan, Renxiang; Xu, Qiang; Sun, Yang; Jiao, Ruihua

    2015-10-01

    In the present study, the effect of Fumigaclavine C, a fungal metabolite, on murine experimental colitis induced by dextran sulfate sodium (DSS) and its possible mechanism were examined in vivo and vitro. Oral administration of Fumigaclavine C dose-dependently attenuated the loss of body weight and shortening of colon length induced by DSS. The disease activity index, histopathologic scores of musco was also significantly reduced by Fumigaclavine C treatment. Protein and mRNA levels of DSS-induced pro-inflammatory cytokines in colon, including TNF-α, IL-1β and IL-17A, were markedly suppressed by Fumigaclavine C. At the same time, decreased activation of caspase-1 in peritoneal macrophages was detected in Fumigaclavine C -treated mice which suggested that the NLRP3 inflammasome activation was suppressed. Furthermore, in the LPS plus ATP cell model, we found that Fumigaclavine C dose-dependent inhibited IL-1β release and caspase-1 activation. Taken together, our results demonstrate the ability of Fumigaclavine C to inhibit NLRP3 inflammasome activation and give some evidence for its potential use in the treatment of inflammatory bowel diseases. PMID:26320672

  6. An experimental setup to characterize MR switched gradient-induced potentials.

    PubMed

    Fokapu, Odette; El-Tatar, Aziz

    2013-06-01

    We have developed an experimental setup as an in vitro research tool for studying the contamination of electrophysiological signals (EPS) by MRI environment; particularly, when due to the switched gradient-induced potentials. The system is composed of: 1) a MRI compatible module for the transmission of the EPS into the MRI tunnel, 2) a gelatin-based tissue-mimicking phantom, placed inside the tunnel, in which EPS is injected, 3) a detection module composed of a five input channel MRI compatible transmitter placed inside the tunnel, allowing an on-site pre-amplification of the bio-potentials and their transmission, via an optical fiber cable, to a four filtered output per channel receiver (350 Hz, 160 Hz, 80 Hz, and 40 Hz, for a total of 20 channels) placed in the control room, and 4) a signal processing algorithm used to analyze the generated induced potentials. A set of tests were performed to validate the electronic performances of the setup. We also present in this work an interesting application of the setup, i.e., the acquisition and analysis of the induced potentials with respect of the slice orientation for a given MRI sequence. Significant modifications of the time and frequency characteristics were observed with respect to axial, coronal or sagittal orientations. PMID:23853335

  7. Dyspnea in a case of shoulder dislocation – to beware of this rare life-threatening symptom

    PubMed Central

    Joshi, Satyen Praful; Challawar, Nikhil Subhash; Agrawal, Parth Vinod; Gajjar, Arpit S.

    2016-01-01

    Shoulder dislocation is a common injury in orthopedic practice. In an acute presentation, closed reduction of the shoulder joint leads to an uneventful recovery. However, in the developing world neglected shoulder dislocation and treatments from quacks are not uncommon. Improper treatment and neglect can rarely become life threatening. We present one such case, emphasizing the need to investigate the symptom of dyspnea in a patient with history of shoulder dislocation. PMID:27658507

  8. Dyspnea on exertion in patients of heart failure as a consequence of obesity: An observational study.

    PubMed

    Baikampady, Savitri Vasudev

    2013-04-01

    Heart failure (HF) is the inability of the heart to fill with or pump out enough blood to meet the body's needs. It is not one single disease, but rather a group of signs and symptoms caused by many different disease processes that have weakened the heart over time and left it unable to pump blood efficiently. Hypertension, diabetes mellitus, cardiovascular disorders are few of such disease processes responsible for conditions in HF. Even though, the co-morbidities mentioned above are well-established in the present system of medicine, its association with respiratory risk on obese patients especially in HF, still needs to be explored. The aim of this study is to determine the presence of dyspnea on exertion (DOE) in patients of HF as a consequence of obesity. Strategies to prevent the risk of HF, which would complement the current approaches aimed at Ayurvedic perspective especially, the obesity, its related comorbidities and contributors in the form of information on life-style leading to obesity needs to be focused. An ethical clearance for the project from the same institute was obtained on 101 patients of HF. All patients with ejection fraction <50% having DOE, New York Heart Association category were selected. Those with restrictive cardiomyopathy valvular abnormalities and under psychiatry treatment were excluded. Patients were informed about the project and their written consent was obtained followed by filling the Case Report Form (CRF). Their recent reports of left ventricular ejection fraction were attached along with details of 6 min hall walk test. Analysis was performed using the Statistical Package for the Social Sciences software, IBM version-17.0. The significant outcomes on lifestyles of HF related to co-morbidities were found. PMID:24250124

  9. Unexplained exertional dyspnea caused by low ventricular filling pressures: results from clinical invasive cardiopulmonary exercise testing

    PubMed Central

    Lewis, Gregory D.; Opotowsky, Alexander R.; Waxman, Aaron B.; Systrom, David M.

    2016-01-01

    Abstract To determine whether low ventricular filling pressures are a clinically relevant etiology of unexplained dyspnea on exertion, a database of 619 consecutive, clinically indicated invasive cardiopulmonary exercise tests (iCPETs) was reviewed to identify patients with low maximum aerobic capacity (V̇o2max) due to inadequate peak cardiac output (Qtmax) with normal biventricular ejection fractions and without pulmonary hypertension (impaired: n = 49, V̇o2max = 53% predicted [interquartile range (IQR): 47%–64%], Qtmax = 72% predicted [62%–76%]). These were compared to patients with a normal exercise response (normal: n = 28, V̇o2max = 86% predicted [84%–97%], Qtmax = 108% predicted [97%–115%]). Before exercise, all patients received up to 2 L of intravenous normal saline to target an upright pulmonary capillary wedge pressure (PCWP) of ≥5 mmHg. Despite this treatment, biventricular filling pressures at peak exercise were lower in the impaired group than in the normal group (right atrial pressure [RAP]: 6 [IQR: 5–8] vs. 9 [7–10] mmHg, P = 0.004; PCWP: 12 [10–16] vs. 17 [14–19] mmHg, P < 0.001), associated with decreased stroke volume (SV) augmentation with exercise (+13 ± 10 [standard deviation (SD)] vs. +18 ± 10 mL/m2, P = 0.014). A review of hemodynamic data from 23 patients with low RAP on an initial iCPET who underwent a second iCPET after saline infusion (2.0 ± 0.5 L) demonstrated that 16 of 23 patients responded with increases in Qtmax ([+24% predicted [IQR: 14%–34%]), V̇o2max (+10% predicted [7%–12%]), and maximum SV (+26% ± 17% [SD]). These data suggest that inadequate ventricular filling related to low venous pressure is a clinically relevant cause of exercise intolerance. PMID:27162614

  10. Unexplained exertional dyspnea caused by low ventricular filling pressures: results from clinical invasive cardiopulmonary exercise testing.

    PubMed

    Oldham, William M; Lewis, Gregory D; Opotowsky, Alexander R; Waxman, Aaron B; Systrom, David M

    2016-03-01

    To determine whether low ventricular filling pressures are a clinically relevant etiology of unexplained dyspnea on exertion, a database of 619 consecutive, clinically indicated invasive cardiopulmonary exercise tests (iCPETs) was reviewed to identify patients with low maximum aerobic capacity (V̇o2max) due to inadequate peak cardiac output (Qtmax) with normal biventricular ejection fractions and without pulmonary hypertension (impaired: n = 49, V̇o2max = 53% predicted [interquartile range (IQR): 47%-64%], Qtmax = 72% predicted [62%-76%]). These were compared to patients with a normal exercise response (normal: n = 28, V̇o2max = 86% predicted [84%-97%], Qtmax = 108% predicted [97%-115%]). Before exercise, all patients received up to 2 L of intravenous normal saline to target an upright pulmonary capillary wedge pressure (PCWP) of ≥5 mmHg. Despite this treatment, biventricular filling pressures at peak exercise were lower in the impaired group than in the normal group (right atrial pressure [RAP]: 6 [IQR: 5-8] vs. 9 [7-10] mmHg, P = 0.004; PCWP: 12 [10-16] vs. 17 [14-19] mmHg, P < 0.001), associated with decreased stroke volume (SV) augmentation with exercise (+13 ± 10 [standard deviation (SD)] vs. +18 ± 10 mL/m(2), P = 0.014). A review of hemodynamic data from 23 patients with low RAP on an initial iCPET who underwent a second iCPET after saline infusion (2.0 ± 0.5 L) demonstrated that 16 of 23 patients responded with increases in Qtmax ([+24% predicted [IQR: 14%-34%]), V̇o2max (+10% predicted [7%-12%]), and maximum SV (+26% ± 17% [SD]). These data suggest that inadequate ventricular filling related to low venous pressure is a clinically relevant cause of exercise intolerance. PMID:27162614

  11. Spontaneous and experimental glycoprotein storage disease of goats induced by Ipomoea carnea subsp fistulosa (Convolvulaceae).

    PubMed

    Armién, A G; Tokarnia, C H; Peixoto, P Vargas; Frese, K

    2007-03-01

    Spontaneous and experimental poisoning with the swainsonine-containing and calystegine-containing plant Ipomoea carnea subsp fistulosa is described. Three of 8 goats presenting with emaciation, weakness, symmetrical ataxia, posterior paresis, proprioceptive deficits, abnormal posture, abnormal postural reaction, and muscle hypertonia were necropsied. I fistulosa was suspected to be the cause of the neurologic disease in all cases. An experiment was conducted to confirm the diagnosis using 12 goats and diets containing 3 different concentrations of the plant. All goats fed I fistulosa developed neurological signs that were similar to those observed in the spontaneous intoxication. Muscle atrophy and pallor were the only macroscopic changes observed in spontaneous and in experimental intoxication. Histological lesions of spontaneous and experimental animals were similar. The most prominent lesion was cytoplasmic vacuolation in neurons of the central and the autonomous nervous system, pancreatic acinar cells, hepatocytes, Kupffer cells, follicular epithelial cells of the thyroid gland, and macrophages of the lymphatic tissues. Neuronal necrosis, axonal spheroids formation, and astrogliosis were additionally observed in the brain. Ultrastructurally, the cytoplasmic vacuoles consisted of distended lysosomes surrounded by a single-layered membrane. Nonreduced end-rests or sequence of alpha-Man, alpha-Glc, beta(1-4)-GlcNAc, and NeuNAc on lysosomal membrane were revealed by lectin histochemistry. Samples of plants used in the experimental trial contained swainsonine and calystegine and their intermediary derivate. We conclude that I fistulosa induces a glycoprotein storage disease primarily based on the inhibition of the lysosomal alpha-mannosidase by the alkaloid swainsonine. PMID:17317794

  12. Neutrophil Extracellular Traps Induce Organ Damage during Experimental and Clinical Sepsis.

    PubMed

    Czaikoski, Paula Giselle; Mota, José Maurício Segundo Correia; Nascimento, Daniele Carvalho; Sônego, Fabiane; Castanheira, Fernanda Vargas e Silva; Melo, Paulo Henrique; Scortegagna, Gabriela Trentin; Silva, Rangel Leal; Barroso-Sousa, Romualdo; Souto, Fabrício Oliveira; Pazin-Filho, Antonio; Figueiredo, Florencio; Alves-Filho, José Carlos; Cunha, Fernando Queiróz

    2016-01-01

    Organ dysfunction is a major concern in sepsis pathophysiology and contributes to its high mortality rate. Neutrophil extracellular traps (NETs) have been implicated in endothelial damage and take part in the pathogenesis of organ dysfunction in several conditions. NETs also have an important role in counteracting invading microorganisms during infection. The aim of this study was to evaluate systemic NETs formation, their participation in host bacterial clearance and their contribution to organ dysfunction in sepsis. C57Bl/6 mice were subjected to endotoxic shock or a polymicrobial sepsis model induced by cecal ligation and puncture (CLP). The involvement of cf-DNA/NETs in the physiopathology of sepsis was evaluated through NETs degradation by rhDNase. This treatment was also associated with a broad-spectrum antibiotic treatment (ertapenem) in mice after CLP. CLP or endotoxin administration induced a significant increase in the serum concentrations of NETs. The increase in CLP-induced NETs was sustained over a period of 3 to 24 h after surgery in mice and was not inhibited by the antibiotic treatment. Systemic rhDNase treatment reduced serum NETs and increased the bacterial load in non-antibiotic-treated septic mice. rhDNase plus antibiotics attenuated sepsis-induced organ damage and improved the survival rate. The correlation between the presence of NETs in peripheral blood and organ dysfunction was evaluated in 31 septic patients. Higher cf-DNA concentrations were detected in septic patients in comparison with healthy controls, and levels were correlated with sepsis severity and organ dysfunction. In conclusion, cf-DNA/NETs are formed during sepsis and are associated with sepsis severity. In the experimental setting, the degradation of NETs by rhDNase attenuates organ damage only when combined with antibiotics, confirming that NETs take part in sepsis pathogenesis. Altogether, our results suggest that NETs are important for host bacterial control and are

  13. Coupled plasma filtration adsorption in experimental peritonitis-induced septic shock.

    PubMed

    Sykora, Roman; Chvojka, Jiri; Krouzecky, Ales; Radej, Jaroslav; Kuncova, Jitka; Varnerova, Veronika; Karvunidis, Thomas; Novak, Ivan; Matejovic, Martin

    2009-05-01

    The coupled plasma filtration adsorption (CPFA) was developed as an adsorptive hemopurification method aimed at nonselective removal of circulating soluble mediators potentially involved in the pathogenesis of sepsis. We hypothesized that this nonselective hemopurification could protect from detrimental consequences of long-term, volume-resuscitated porcine septic shock. In 16 anesthetized, mechanically ventilated, and instrumented pigs, the hyperdynamic septic shock secondary to peritonitis was induced by intraperitoneally inoculating feces and maintained for 22 h with fluid resuscitation and norepinephrine infusion as needed to maintain MAP above 65 mmHg. After 12 h of peritonitis, animals were randomized to receive either supportive treatment (control, n = 8) or CPFA treatment (CPFA, n = 8). Systemic, hepatosplanchnic, and renal hemodynamics; oxygen exchange; energy metabolism (lactate/pyruvate and ketone body ratios); ileal mucosal and renal cortex microcirculation; systemic inflammation (TNF-alpha, IL-6); nitrosative/oxidative stress (thiobarbituric acid reactive species, nitrates + nitrites); and endothelial/coagulation dysfunction (asymmetric dimethylarginine, von Willebrand factor, thrombin-antithrombin complexes, platelet count) were assessed before and 12, 18, and 22 h of peritonitis. Coupled plasma filtration adsorption neither delayed the development of hypotension nor reduced the dose of norepinephrine. The treatment failed to attenuate sepsis-induced alterations in microcirculation, surrogate markers of cellular energetics, endothelial injury, and systemic inflammation. Similarly, CPFA did not protect from lung and liver dysfunction and even aggravated sepsis-induced disturbances in coagulation and oxidative/nitrosative stress. In this porcine model of septic shock, the early treatment with CPFA was not capable of reversing the sepsis-induced disturbances in various biological pathways and organ systems. Both the efficacy and safety of this method

  14. Effect of different doses of Manuka honey in experimentally induced inflammatory bowel disease in rats.

    PubMed

    Prakash, A; Medhi, B; Avti, P K; Saikia, U N; Pandhi, P; Khanduja, K L

    2008-11-01

    To evaluate the effect of different doses of Manuka honey in experimentally induced inflammatory bowel disease in rats. Adult Wistar rats of either sex were used (n = 30). Colitis was induced by a single intracolonic administration of TNBS dissolved in 35% ethanol. The rats (n = 30) were divided into five groups (n = 6) and were treated with vehicle (ethanol), TNBS, Manuka honey (5 g/kg, p.o.), Manuka honey (10 g/kg, p.o.) or sulfasalazine (360 mg/kg, p.o.) body weight for 14 days. After completion of treatment, the animals were killed and the following parameters were assessed: morphological score, histological score and different antioxidant parameters.Manuka honey at different doses provided protection against TNBS-induced colonic damage. There was significant protection with Manuka honey 5 g/kg as well as with 10 g/kg body weight compared with the control (p < 0.001). All the treated groups showed reduced colonic inflammation and all the biochemical parameters were significantly reduced compared with the control in the Manuka honey treated groups (p < 0.001). Manuka honey at different doses restored lipid peroxidation as well as improved antioxidant parameters. Morphological and histological scores were significantly reduced in the low dose Manuka honey treated group (p < 0.001). In the inflammatory model of colitis, oral administration of Manuka honey 5 g/kg and Manuka honey 10 g/kg body weight significantly reduced the colonic inflammation. The present study indicates that Manuka honey is efficacious in the TNBS-induced rat colitis model, but these results require further confirmation in human studies.

  15. Correlation Between Stereoacuity and Experimentally Induced Graded Monocular and Binocular Astigmatism

    PubMed Central

    Puthran, Neelam; Gagal, Bhavna

    2016-01-01

    Introduction Stereopsis, the highest grade of binocular single vision, is affected by various factors, such as mis-alignment of visual axes, refractive errors especially anisometropia and astigmatism, both of which may result in amblyopia. There are very few studies in literature regarding the relationship between stereoacuity and refractive errors, especially astigmatism. Aim The present study was conducted to determine the correlation between stereoacuity and experimentally induced graded astigmatism in emmetropes. Materials and Methods A randomized study was conducted on 2000 individuals of either gender, between the ages of 8-35 years, at tertiary care centre attached to a medical college during the period of August 2012 to August 2014, All subjects were emmetropic with normal binocular single vision. Participants were randomly divided into four groups of 500 individuals each. Two groups were subjected to induced myopic astigmatism, either uni-ocularly or binocularly, using + 1.0 D and + 2.0 D cylinders at varying axes i.e., 450, 900 and 1800. Similarily, the remaining two groups were subjected to induced hypermetropic astigmatism, using - 1.0 D and - 2.0D cylinders at varying axes i.e. 450, 900 and 1800. Near stereoacuity was determined by the Titmus Fly Stereo Test, both before and after induction of astigmatism. Statistical analysis was done using paired t-test and ANOVA. Results The mean stereoacuity in emmetropes was 28.81±4.97 seconds of arc. There was a decrease in stereoacuity with increase in dioptric power of astigmatism (p<0.001). Oblique astigmatism reduced the stereoacuity maximally, while stereoacuity was least affected at 180o axis. Hypermetropic astigmatism caused more deterioration in stereoacuity than myopic astigmatism. A gross reduction in stereoacuity was noted in induced monocular astigmatism as against binocular astigmatism. Conclusion This study suggests that stereoacuity is significantly affected by even minor degrees of monocular or

  16. Methanolic extract of Anthocephalus cadamba induces apoptosis in Ehrlich ascites carcinoma cells in experimental mice

    PubMed Central

    Dolai, Narayan; Islam, Aminul; Haldar, Pallab Kanti

    2016-01-01

    Objective: Anthocephalus cadamba (Roxb.) Miq. (Family: Rubiaceae), a folk medicine commonly known as “Kadam” in Bengali, has been used for the treatment of tumor. The methanolic extract of A. cadamba (MEAC) showing antitumor activity on Ehrlich ascites carcinoma (EAC) cells treated mice was already reported. This study was designed to study the apoptosis-inducing property of MEAC and its mechanism in EAC cells in mice. Materials and Methods: Apoptogenic morphology was determined by fluorescent DNA-binding double staining method using dyes acridine orange (AO)/ethidium bromide (EB). Comet assay was estimated to check the DNA damage. Flow cytometry (fluorescence-activated cell sorting [FACS]) was used to detect the apoptotic rate quantitatively by double labeling techniques using annexin V FITC/propidium iodide staining. Apoptotic protein expression was done using Western blotting assay method. Statistical Analysis: Results are expressed as mean ± standard deviation. Statistical analysis was performed using ANOVA followed by Dunnett's post hoc test of GraphPad Prism software. *P < 0.05, **P < 0.01 and ***P < 0.001 were considered statistically significant. Results: Apoptosis-inducing effect of MEAC on EAC cells was confirmed from AO/EB staining and FACS analysis. MEAC treatment showed dose-dependent induction of DNA damage. Apoptosis was induced by increasing the expression of multiple downstream factors such as pro-apoptotic protein p53 and p21 in EAC. Bax was up-regulated and anti-apoptotic protein Bcl-2 was down-regulated resulting in decrease of the Bcl-2/Bax ratio by MEAC treatment. Conclusion: Experimental results revealed that MEAC induces apoptosis by modulating the expression of some pro-apoptotic and anti-apoptotic proteins in EAC and thus exerts its anti-tumor activity. PMID:27756959

  17. Protein and microRNA biomarkers from lavage, urine, and serum in military personnel evaluated for dyspnea

    PubMed Central

    2014-01-01

    Background We have identified candidate protein and microRNA (miRNA) biomarkers for dyspnea by studying serum, lavage fluid, and urine from military personnel who reported serious respiratory symptoms after they were deployed to Iraq or Afghanistan. Methods Forty-seven soldiers with the complaint of dyspnea who enrolled in the STudy of Active Duty Military Personnel for Environmental Dust Exposure (STAMPEDE) underwent comprehensive pulmonary evaluations at the San Antonio Military Medical Center. The evaluation included fiber-optic bronchoscopy with bronchoalveolar lavage. The clinical findings from the STAMPEDE subjects pointed to seven general underlying diagnoses or findings including airway hyperreactivity, asthma, low diffusivity of carbon monoxide, and abnormal cell counts. The largest category was undiagnosed. As an exploratory study, not a classification study, we profiled proteins or miRNAs in lavage fluid, serum, or urine in this group to look for any underlying molecular patterns that might lead to biomarkers. Proteins in lavage fluid and urine were identified by accurate mass tag (database-driven) proteomics methods while miRNAs were profiled by a hybridization assay applied to serum, urine, and lavage fluid. Results Over seventy differentially expressed proteins were reliably identified both from lavage and from urine in forty-eight dyspnea subjects compared to fifteen controls with no known lung disorder. Six of these proteins were detected both in urine and lavage. One group of subjects was distinguished from controls by expressing a characteristic group of proteins. A related group of dyspnea subjects expressed a unique group of miRNAs that included one miRNA that was differentially overexpressed in all three fluids studied. The levels of several miRNAs also showed modest but direct associations with several standard clinical measures of lung health such as forced vital capacity or gas exchange efficiency. Conclusions Candidate proteins and mi

  18. Protein and microRNA biomarkers from lavage, urine, and serum in military personnel evaluated for dyspnea

    SciTech Connect

    Brown, Joseph N.; Brewer, Heather M.; Nicora, Carrie D.; Weitz, Karl K.; Morris, Michael J.; Skabelund, Andrew J.; Adkins, Joshua N.; Smith, Richard D.; Cho, Ji -Hoon; Gelinas, Richard

    2014-10-05

    Background: We have identified candidate protein and microRNA (miRNA) biomarkers for dyspnea by studying serum, lavage fluid, and urine from military personnel who reported serious respiratory symptoms after they were deployed to Iraq or Afghanistan. Methods: Forty-seven soldiers with the complaint of dyspnea who enrolled in the STudy of Active Duty Military Personnel for Environmental Dust Exposure (STAMPEDE) underwent comprehensive pulmonary evaluations at the San Antonio Military Medical Center. The evaluation included fiber-optic bronchoscopy with bronchoalveolar lavage. The clinical findings from the STAMPEDE subjects pointed to seven general underlying diagnoses or findings including airway hyperreactivity, asthma, low diffusivity of carbon monoxide, and abnormal cell counts. The largest category was undiagnosed. As an exploratory study, not a classification study, we profiled proteins or miRNAs in lavage fluid, serum, or urine in this group to look for any underlying molecular patterns that might lead to biomarkers. Proteins in lavage fluid and urine were identified by accurate mass tag (database-driven) proteomics methods while miRNAs were profiled by a hybridization assay applied to serum, urine, and lavage fluid. Results: Over seventy differentially expressed proteins were reliably identified both from lavage and from urine in forty-eight dyspnea subjects compared to fifteen controls with no known lung disorder. Six of these proteins were detected both in urine and lavage. One group of subjects was distinguished from controls by expressing a characteristic group of proteins. A related group of dyspnea subjects expressed a unique group of miRNAs that included one miRNA that was differentially overexpressed in all three fluids studied. The levels of several miRNAs also showed modest but direct associations with several standard clinical measures of lung health such as forced vital capacity or gas exchange efficiency. Conclusions: Candidate proteins and mi

  19. Protein and microRNA biomarkers from lavage, urine, and serum in military personnel evaluated for dyspnea

    DOE PAGESBeta

    Brown, Joseph N.; Brewer, Heather M.; Nicora, Carrie D.; Weitz, Karl K.; Morris, Michael J.; Skabelund, Andrew J.; Adkins, Joshua N.; Smith, Richard D.; Cho, Ji -Hoon; Gelinas, Richard

    2014-10-05

    Background: We have identified candidate protein and microRNA (miRNA) biomarkers for dyspnea by studying serum, lavage fluid, and urine from military personnel who reported serious respiratory symptoms after they were deployed to Iraq or Afghanistan. Methods: Forty-seven soldiers with the complaint of dyspnea who enrolled in the STudy of Active Duty Military Personnel for Environmental Dust Exposure (STAMPEDE) underwent comprehensive pulmonary evaluations at the San Antonio Military Medical Center. The evaluation included fiber-optic bronchoscopy with bronchoalveolar lavage. The clinical findings from the STAMPEDE subjects pointed to seven general underlying diagnoses or findings including airway hyperreactivity, asthma, low diffusivity of carbonmore » monoxide, and abnormal cell counts. The largest category was undiagnosed. As an exploratory study, not a classification study, we profiled proteins or miRNAs in lavage fluid, serum, or urine in this group to look for any underlying molecular patterns that might lead to biomarkers. Proteins in lavage fluid and urine were identified by accurate mass tag (database-driven) proteomics methods while miRNAs were profiled by a hybridization assay applied to serum, urine, and lavage fluid. Results: Over seventy differentially expressed proteins were reliably identified both from lavage and from urine in forty-eight dyspnea subjects compared to fifteen controls with no known lung disorder. Six of these proteins were detected both in urine and lavage. One group of subjects was distinguished from controls by expressing a characteristic group of proteins. A related group of dyspnea subjects expressed a unique group of miRNAs that included one miRNA that was differentially overexpressed in all three fluids studied. The levels of several miRNAs also showed modest but direct associations with several standard clinical measures of lung health such as forced vital capacity or gas exchange efficiency. Conclusions: Candidate proteins

  20. The use of airborne imaging spectrometer data to determine experimentally induced variation in coniferous canopy chemistry

    NASA Technical Reports Server (NTRS)

    Swanberg, Nancy A.; Matson, Pamela A.

    1987-01-01

    It was experimentally determined whether induced differences in forest canopy chemical composition can be detected using data from the Airborne Imaging Spectrometer (AIS). Treatments were applied to an even-aged forest of Douglas fir trees. Work to date has stressed wet chemical analysis of foilage samples and correction of AIS data. Plot treatments were successful in providing a range of foliar N2 concentrations. Much time was spent investigating and correcting problems with the raw AIS data. Initial problems with groups of drop out lines in the AIS data were traced to the tape recorder and the tape drive. Custom adjustment of the tape drive led to recovery of most missing lines. Remaining individual drop out lines were replaced using average of adjacent lines. Application of a notch filter to the Fourier transform of the image in each band satisfactorily removed vertical striping. The aspect ratio was corrected by resampling the image in the line direction using nearest neighbor interpolation.

  1. Experimental studies of collective excitations of a BEC in light-induced gauge fields

    NASA Astrophysics Data System (ADS)

    Li, Chuan-Hsun; Niffenegger, Robert; Blasing, David; Olson, Abraham; Chen, Yong P.

    2015-05-01

    We present our experimental studies of collective modes including spin dipole mode and scissors mode of a 87Rb Bose-Einstein condensate (BEC) in the presence of Raman light-induced gauge fields and synthetic spin-orbit coupling (SOC). By Raman dressing the mf spin states within the F =1 manifold, we engineer atoms' energy-momentum dispersion to create synthetic SOC, and spin dependent synthetic electric and magnetic fields. We have used spin dependent synthetic electric fields to make two BECs with different spins oscillate and collide in the optical trap. We have studied the effects of SOC on both the momentum damping and thermalization behaviors of the BECs when undergoing such spin dipole oscillations. We have also used spatially dependent synthetic electric fields to excite the scissors mode, which has been used as a probe for superfluidity. We have investigated the effects of the synthetic gauge fields and SOC on the measured scissors mode.

  2. Theoretical and experimental study of electromagnetic forces induced in one-dimensional photonic crystals

    NASA Astrophysics Data System (ADS)

    Lugo, J. E.; Doti, Rafael; Faubert, Jocelyn; Sanchez, Noemi; Sanchez, Javier; Palomino, Martha A.; de la Mora, M. Beatriz; del Rio, J. Antonio

    2013-10-01

    We studied theoretically and experimentally the induction of electromagnetic forces in one-dimensional photonic crystals with localized defects when light impinges transversally to the defect layer. The theoretical calculations indicate that the electromagnetic forces increases at a certain frequency that coincide with a defect photonic state. The photonic structure consists of a microcavity like structure formed of two one-dimensional photonic crystals made of free-standing porous silicon, separated by variable air gap and the working wavelength is 633 nm. The force generation is made evident by driving a laser light by means of a chopper; the light hits the photonic structure and induces a vibration and the vibration is characterized by using a very sensitive vibrometer.

  3. Recurrent aerosol antigen exposure induces distinct patterns of experimental allergic asthma in mice.

    PubMed

    Jungsuwadee, Paiboon; Dekan, Gerhard; Stingl, Georg; Epstein, Michelle M

    2002-02-01

    Patients with allergic asthma present clinically with chronic or intermittent disease caused by either persistent or periodic allergen exposure. We sought to generate clinically relevant disease in mice, which would reflect the relapsing, remitting, and constant nature of this syndrome. We generated and compared acute onset, remission, relapse, and overt phases of the disease and found that acute disease was characterized by airway hyperreactivity, eosinophilic lung inflammation, excessive mucus production, and antigen-specific antibody and was rapidly followed by a remission. Mice rechallenged with aerosol antigen during the remission or treated with repeated aerosol challenges developed relapse and overt disease, respectively. Recurrent antigen exposure induced a progressive increase in bronchoalveolar lavage fluid immunoglobulin, mucus production, and a change in inflammatory infiltrates indicating a transition from acute to chronic inflammation. These data demonstrate distinct phases of disease representing a clinical spectrum of experimental allergic asthma and may have important implications for new treatment strategies.

  4. An experimental investigation of vortex-induced vibration with nonlinear restoring forces

    NASA Astrophysics Data System (ADS)

    Mackowski, A. W.; Williamson, C. H. K.

    2013-08-01

    We experimentally examine the amplitude of a bluff body undergoing vortex-induced vibration (VIV) supported by linear and various nonlinear structural forces. This investigation is made possible by our Cyber-Physical Fluid Dynamics force-feedback technique; using it, we can impose arbitrary nonlinear restoring forces on a circular cylinder in our water channel. For the range of nonlinearities examined, detailed analysis allows one to understand and predict the response of the nonlinear structural system using knowledge of a standard, linear VIV system. We also present a case study examining the potential of nonlinear springs to aid in a VIV-based energy harvesting device. Appropriate choices of the spring's nonlinearity allow the hypothetical energy harvester to operate at high performance over a much larger range of Reynolds number than a standard system.

  5. Experimental investigation of a supersonic swept ramp injector using laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Hartfield, Roy J.; Hollo, Steven D.; Mcdaniel, James C.

    1990-01-01

    Planar measurements of injectant mole fraction and temperature have been conducted in a nonreacting supersonic combustor configured with underexpanded injection in the base of a swept ramp. The temperature measurements were conducted with a Mach 2 test section inlet in streamwise planes perpendicular to the test section wall on which the ramp was mounted. Injection concentration measurements, conducted in cross flow planes with both Mach 2 and Mach 2.9 free stream conditions, dramatically illustrate the domination of the mixing process by streamwise vorticity generated by the ramp. These measurements, conducted using a nonintrusive optical technique (laser-induced iodine fluorescence), provide an accurate and extensive experimental data base for the validation of computation fluid dynamic codes for the calculation of highly three-dimensional supersonic combustor flow fields.

  6. Experimental study of the water jet induced by underwater electrical discharge in a narrow rectangular tube

    NASA Astrophysics Data System (ADS)

    Koita, T.; Zhu, Y.; Sun, M.

    2016-05-01

    This paper reports an experimental investigation on the effects of explosion depth and tube width on the water jet induced by an underwater electrical discharge in a narrow rectangular tube. The water jet formation and bubble structure were evaluated from the images recorded by a high-speed video camera. Two typical patterns of jet formation and four general patterns of bubble implosion were observed, depending on the explosion depth and tube width. The velocity of the water jet was calculated from the recorded images. The jet velocity was observed to depend on not only the explosion depth and energy, but also on the tube width. We proposed an empirical formula defining the water jet velocity in the tube as a function of the tube width and explosion depth and energy.

  7. Anti-arthritic effect of eugenol on collagen-induced arthritis experimental model.

    PubMed

    Grespan, Renata; Paludo, Marcia; Lemos, Henrique de Paula; Barbosa, Carmem Patrícia; Bersani-Amado, Ciomar Aparecida; Dalalio, Marcia Machado de Oliveira; Cuman, Roberto Kenji Nakamura

    2012-01-01

    This study was designed to test the efficacy of eugenol, a compound obtained from the essential oil of cloves (Syzygium aromaticum) in collagen-induced arthritis (CIA), a well characterized murine model of rheumatoid arthritis. Macroscopic clinical evidence of CIA manifests first as periarticular erythema and edema in the hind paws. Treatment with eugenol starting at the onset of arthritis (day 25) ameliorated these clinical signs of CIA. Furthermore, eugenol inhibited mononuclear cell infiltration into the knee joints of arthritic mice and also lowered the levels of cytokines (tumor necrosis factor (TNF)-α, interferon (IFN)-γ and tumor growth factor (TGF)-β) within the ankle joints. Eugenol treatment did not affect the in vitro cell viability as assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Therefore, eugenol ameliorates experimental arthritis and could be useful as a beneficial supplement in treating human arthritis. PMID:23037170

  8. An explanation for experimental observations of harmonic cyclotron emission induced by fast ions

    SciTech Connect

    Chen, K.R.; Horton, W.; Van Dam, J.W.

    1993-09-01

    An explanation, supported by numerical simulations and analytical theory, is given for the harmonic cyclotron emission induced by fast ions in tokamak plasmas - particular, for the emission observed at low harmonics in deuterium-deuterium md deuterium-tritium experiments in the Joint European Tokamak. We show that the first proton harmonic is one of the highest spectral peaks whereas the first alpha is weak. We also compare the relative spectral amplitudes of different harmonics. Our results axe consistent with the experimental observations. The simulations verify that the instabilities are caused by a weak relativistic mass effect. Simulation that a nonuniform magnetic field leads to no appreciable change in the growth and saturation amplitude of the waves.

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

    NASA Astrophysics Data System (ADS)

    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.

  10. Modulation of diabetes-mellitus-induced male reproductive dysfunctions in experimental animal models with medicinal plants

    PubMed Central

    Jain, Gyan Chand; Jangir, Ram Niwas

    2014-01-01

    Today diabetes mellitus has emerged as a major healthcare problem throughout the world. It has recently broken the age barrier and has been diagnosed in younger people also. Sustained hyperglycemia is associated with many complications including male reproductive dysfunctions and infertility. Numerous medicinal plants have been used for the management of the diabetes mellitus in various traditional system of medicine and in folklore worldwide as they are a rich source of bioactive phytoconstituents, which lower blood glucose level and/or also act as antioxidants resulting in the amelioration of oxidative-stress-induced diabetic complications. The present review describes the ameliorative effects of medicinal plants or their products, especially on male reproductive dysfunctions, in experimental diabetic animal models. PMID:25125884

  11. Nanolesions induced by heavy ions in human tissues: Experimental and theoretical studies

    PubMed Central

    Bleicher, Marcus; Burigo, Lucas; Herrlitz, Maren; Krämer, Michael; Mishustin, Igor; Müller, Iris; Natale, Francesco; Pshenichnov, Igor; Schramm, Stefan; Taucher-Scholz, Gisela; Wälzlein, Cathrin

    2012-01-01

    Summary The biological effects of energetic heavy ions are attracting increasing interest for their applications in cancer therapy and protection against space radiation. The cascade of events leading to cell death or late effects starts from stochastic energy deposition on the nanometer scale and the corresponding lesions in biological molecules, primarily DNA. We have developed experimental techniques to visualize DNA nanolesions induced by heavy ions. Nanolesions appear in cells as “streaks” which can be visualized by using different DNA repair markers. We have studied the kinetics of repair of these “streaks” also with respect to the chromatin conformation. Initial steps in the modeling of the energy deposition patterns at the micrometer and nanometer scale were made with MCHIT and TRAX models, respectively. PMID:23019551

  12. Experimental investigation of the flow-induced vibration of hydrofoils in cavitating flows

    NASA Astrophysics Data System (ADS)

    Wang, Guoyu; Wu, Qin; Huang, Biao; Gao, Yuan

    2015-12-01

    The objective of this paper is to investigate the correlation between fluid induced vibration and unsteady cavitation behaviours. Experimental results are presented for a modified NACA66 hydrofoil, which is fixed at α=8°. The high-speed camera is synchronized with a single point Laser Doppler Vibrometer to analyze the transient cavitating flow structures and the corresponding structural vibration characteristics. The results showed that, with the decreasing of the cavitation number, the cavitating flows in a water tunnel display several types of cavitation patterns, such as incipient cavitation, sheet cavitation and cloud cavitation. The cavity shedding frequency reduces with the decrease of the cavitation number. As for the cloud cavitation regime, the trend of the vibration velocity goes up with the growth of the attached cavity, accompanied with small amplitude fluctuations. Then the collapse and shedding of the large-scale cloud cavities leads to substantial increase of the vibration velocity fluctuations.

  13. Differences in lymphocyte subpopulations and cell counts before and after experimentally induced swine dysentery.

    PubMed

    Jonasson, Robert; Johannisson, Anders; Jacobson, Magdalena; Fellström, Claes; Jensen-Waern, Marianne

    2004-04-01

    The aim of this study was to examine the levels of circulating leukocytes and lymphocyte subpopulations before and immediately after experimentally induced swine dysentery. Twenty-one healthy crossbred pigs (approximately 22 kg) were orally inoculated with Brachyspira hyodysenteriae. Blood was sampled before inoculation and when clinical signs of swine dysentery occurred. Pigs that remained healthy were sampled when killed. Total and differential white blood cell counts were performed, and lymphocyte subpopulations were analysed using flow cytometry. Following a mean incubation period of 13 days, 12 pigs developed swine dysentery, whereas nine remained healthy throughout the study. Before inoculation, pigs that subsequently developed swine dysentery displayed higher levels of circulating gamma delta T cells (mean +/- se; 30.7 +/- 3.5 %) compared with pigs that remained healthy (14.9 +/- 1.4 %). Sick animals also displayed lower levels of CD8 cells (24.6 +/- 1.5 %), cytotoxic/suppressor T cells (10.9 +/- 1.3 %) and CD4 CD8 T cells (8.1 +/- 1.0 %) than the pigs that remained healthy (34.9 +/- 3.1 %; 17.6 +/- 2.0 %; 13.6 +/- 2.3 %). No difference was observed in leukocyte counts before inoculation. At onset of swine dysentery, there was an increase in monocytes (from 1.5 +/- 0.2 x 10 to 3.8 +/- 0.5 x 10 l) and CD4 CD8 T cells (from 5.8 +/- 0.9 to 8.9 +/- 0.7 %). In conclusion, gamma delta T cells and CD8 cells may be associated with susceptibility to experimentally induced swine dysentery, whereas monocytes and CD4 CD8 T cells appear to be the major responding leukocytes during the disease.

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

    PubMed Central

    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

  15. Chronic effort dyspnea explained by lung function tests and by HRCT and CRX radiographic patterns in COPD: a post-hoc analysis in 51 patients.

    PubMed

    Giuntini, Carlo; Camiciottoli, Gianna; Maluccio, Nazzarena Maria; Mariani, Laura; Lavorini, Federico; Pistolesi, Massimo

    2007-09-01

    This paper is a post-hoc analysis of a previous study performed to investigate the relationship between computerized tomography (CT) and lung function in 51 outpatients with mild-to-moderate COPD. We studied whether changes in lung function and radiographic patterns may help to explain dyspnea, the most disturbing symptom in patients with COPD. The Medical Research Council (MRC) dyspnea scale shows, by univariate analysis, a similar strength of association to CT expiratory lung density and to DL(CO), a functional index of lung parenchymal loss. The MRC dyspnea scale shows a somewhat less strength of association with a small vertical heart on plain chest films. In multivariate analysis, the model with the strongest association to the MRC dyspnea scale (r = 0.76, p < 0.0001) contains 4 explanatory variables (DL(CO), FRC, PaCO(2), and radiographic pattern of pulmonary hypertension). We suggest that diffusing capacity reflects the emphysematous component of hyperinflation, associated by definition with destruction of terminal airspace walls, as distinct from the air trapping component, which is ascribed to airway obstruction and associated with FRC. PaCO(2) mainly reflects the ventilatory components, i.e., ventilatory drive and ventilatory constraints, of pulmonary gas exchange in COPD, while radiographic pattern of pulmonary hypertension likely reflects hypoxic vascular changes, which depend mainly on ventilation/perfusion mismatch and give rise to pulmonary arterial hypertension that may contribute per se to dyspnea. In conclusion, our analysis points out that chronic effort dyspnea variance may account for up to 58% (r(2) = 0.58) by lung function tests and radiographic patterns. Thus, about 42% of the MRC dyspnea variance remains unexplained by this model. On the other hand, dyspnea ascertainment is dependent on subjective behavior and evaluation and in tests is influenced by individual performance and perception. For example in the 6-minute walk test, a similar or

  16. Polymethoxy flavonoids, nobiletin and tangeretin, prevent lipopolysaccharide-induced inflammatory bone loss in an experimental model for periodontitis.

    PubMed

    Tominari, Tsukasa; Hirata, Michiko; Matsumoto, Chiho; Inada, Masaki; Miyaura, Chisato

    2012-01-01

    Nobiletin, a polymethoxy flavonoid (PMF), inhibits systemic bone resorption and maintains bone mass in estrogen-deficient ovariectomized mice. This study examined the anti-inflammatory effects of PMFs, nobiletin, and tangeretin on lipopolysaccharide (LPS)-induced bone resorption. Nobiletin and tangeretin suppressed LPS-induced osteoclast formation and bone resorption and suppressed the receptor activator of NFκB ligand-induced osteoclastogenesis in RAW264.7 macrophages. Nobiletin clearly restored the alveolar bone mass in a mouse experimental model for periodontitis by inhibiting LPS-induced bone resorption. PMFs may therefore provide a new therapeutic approach for periodontal bone loss.

  17. Experimentally induced compaction and coalification in peat from the Okefenokee Swamp

    SciTech Connect

    Cecil, C.B.; Stanton, R.W.; Dulong, F.T.; Neuzil, S.G.; Ruppert, L.F.

    1985-01-01

    The effects of temperature (T) and pressure (P) on compaction and coalification of peat were studied in experiments that simulated open and closed systems of burial. In the open system, normal hydrostatic and lithostatic pressure conditions were simulated; in the closed system, hydrostatic and lithostatic pressures were equal. Samples consisted of fibric Taxodium peat and wood collected from the Okefenokee peat swamp. The experimental conditions were increased from ambient T and P to conditions simulating a depth of 900m at 100/sup 0/C over the span of one month and held constant for a second month until the experiment was terminated. The results indicate that more compaction and coalification occurred in the open system than in the closed system. The relative amount of CO/sub 2/ and CH/sub 4/ evolved in the open-system was more than four times the amount evolved in the closed system. The fluorescence spectra of pollen grains also indicate that the artificially induced coalification was greatest in the open system. The experimental data indicate that both compaction and coalification are controlled by peat composition and by P and T conditions during burial. At least in the early stages of coalification, wood in peat is not as compactible as the fibric peat. Anomalies in coal rank and in organic-maturation indicators may be the result of variable pressure conditions that affected or controlled the fugacity or activity of the reaction products during coalification.

  18. Experimentally-induced Increases in Early Gesture Lead to Increases in Spoken Vocabulary

    PubMed Central

    LeBarton, Eve Sauer; Goldin-Meadow, Susan; Raudenbush, Stephen

    2014-01-01

    Differences in vocabulary that children bring with them to school can be traced back to the gestures they produce at 1;2, which, in turn, can be traced back to the gestures their parents produce at the same age (Rowe & Goldin-Meadow, 2009b). We ask here whether child gesture can be experimentally increased and, if so, whether the increases lead to increases in spoken vocabulary. Fifteen children aged 1;5 participated in an 8-week at-home intervention study (6 weekly training sessions plus follow-up 2 weeks later) in which all were exposed to object words, but only some were told to point at the named objects. Before each training session and at follow-up, children interacted naturally with caregivers to establish a baseline against which changes in communication were measured. Children who were told to gesture increased the number of gesture meanings they conveyed, not only during training but also during interactions with caregivers. These experimentally-induced increases in gesture led to larger spoken repertoires at follow-up. PMID:26120283

  19. Role of inducible nitric oxide synthase in the pathogenesis of experimental leptospirosis.

    PubMed

    Prêtre, Gabriela; Olivera, Noelia; Cédola, Maia; Haase, Santiago; Alberdi, Lucrecia; Brihuega, Bibiana; Gómez, Ricardo M

    2011-09-01

    Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) is a radical effector molecule of the innate immune system that can directly inhibit pathogen replication. In order to study subsequent iNOS kidney expression in experimental leptospirosis, Golden Syrian hamsters and C3H/HeJ mice were infected intraperitoneally with 10(2) or 10(7) virulent Leptospira interrogans serovar Copenhageni (LIC) strain Fiocruz L1-130. Results showed increased levels of iNOS mRNA and protein in kidneys of infected animals when compared to that in mock-infected animals. To get a deeper insight into the role of iNOS in experimental leptospirosis, both subject species were treated or not treated with 4-aminopyridine (4-AP, 0.3mg/kg), an iNOS inhibitor. Treatment of infected hamsters with 4-AP accelerated the mortality rate to 100% by one day and increased the mortality rate from 20 to 60% in mice at 14 days post-infection. In kidney tissues, 4-AP treatment increased the bacterial burden, as demonstrated through leptospiral DNA quantification by real-time PCR, and aggravated tubulointerstitial nephritis. In addition, iNOS inhibition reduced the specific humoral response against LIC when compared to that in untreated infected animals. According to these results, iNOS expression and the resulting NO have an important role in leptospirosis.

  20. Naturally occurring and experimentally induced castor bean (Ricinus communis) poisoning in ducks

    USGS Publications Warehouse

    Jensen, W.I.; Allen, J.P.

    1981-01-01

    Castor bean (Ricinus communis) poisoning accounted for the death of several thousand ducks in the Texas panhandle in the fall and winter months of 1969-1971. Signs of intoxication resembled those of botulism, except for mucoid, blood-tinged excreta. The most common lesions were severe fatty change in the liver, widely distributed internal petechial hemorrhages or ecchymoses, and catarrhal enteritis. Nearly intact castor beans were found in the stomach of one duck during field necropsy. Fragments of seed coat resembling castor bean were found in the stomachs of 10 of 14 ducks examined in the laboratory. Clinical signs and postmortem lesions observed in wild ducks were induced experimentally in mallards (Anas platyrhynchos) by force-feeding intact castor beans. Toxicity titrations were erratic, but the LD50 appeared to be between three and four seeds. The mouse toxicity test, used to detect Clostridium botulinum toxin in the blood serum of intoxicated ducks, was negative in every case. Hemagglutination and precipitin tests generally failed to detect castor bean in extracts of excreta or intestinal contents of experimentally intoxicated ducks.

  1. Experimentally induced life-history evolution in a killifish in response to the introduction of guppies.

    PubMed

    Walsh, Matthew R; Reznick, David N

    2011-04-01

    Life-history theory predicts that increased predation on juvenile age/size-classes favors delayed maturation and decreased reproductive investment. Although this theory has received correlative support, experimental tests in nature are rare. In 1976 and 1981, guppies (Poecilia reticulata) were transplanted into localities that previously only contained a killifish, Rivulus hartii. This situation presents an opportunity to experimentally test this life-history prediction because guppies prey upon young Rivulus. We evaluated the response to selection in Rivulus by measuring phenotypic and genotypic divergence between introduction and upstream "control" localities that lack guppies. Contrary to expectations, Rivulus from the introduction sites evolved earlier maturation and increased reproductive investment within 25 years. Such evolutionary changes parallel previous investigations on natural communities of Rivulus, but do not comply with predictions of age/size-specific theory. Guppies also caused reduced densities and increased growth rates of Rivulus, which are hypothesized indirect effects of predation. Additional life-history theories show that changes in density and growth can interact with predator-induced mortality to alter the predicted trajectory of evolution. We discuss how these latter frameworks improve the fit between theory and evolution in Rivulus.

  2. Experimentally Induced Pulpal Lesion and Substance P Expression: Effect of Ketoprofen—A Preliminary Study

    PubMed Central

    Abbate, Gian Marco; Sacerdote, Paola; Amodeo, Giada; Mangano, Alessandro; Levrini, Luca

    2016-01-01

    Objectives. To evaluate substance P (SP) and the effect of ketoprofen administration, a nonsteroidal anti-inflammatory drug (NSAID), on SP in the pulp of upper third molars with experimentally induced pulpal lesion. Materials and Methods. A sample of 20 young systemically healthy adults of both sexes, nonsmokers, with a healthy upper third molar to extract for orthodontic purposes, was selected. Prior to the procedure, an inflammatory process was generated by mechanical exposure of the pulp. After 15 minutes, the pulp was collected using a sterile barbed broach. SP levels were determined by using a commercially available enzyme immunoassay (ELISA) kit. The subjects were randomly divided into two groups: group 1 received a dose of ketoprofen 30 minutes prior to the experimental procedure. The subjects of group 2 did not receive any kind of drug administration. The patients were asked to complete a diary on the postoperative pain. Results. No statistically significant difference could be detected in SP expression between the two groups. In group 1, pain manifestation was significantly delayed in comparison with group 2. Conclusions. Preventive administration of ketoprofen did not significantly affect the pulpal levels of SP but resulted in a significantly postponed manifestation of pain after extraction. PMID:27034673

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

    PubMed

    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.

  4. Experimentally Induced Pulpal Lesion and Substance P Expression: Effect of Ketoprofen-A Preliminary Study.

    PubMed

    Abbate, Gian Marco; Sacerdote, Paola; Amodeo, Giada; Mangano, Alessandro; Levrini, Luca

    2016-01-01

    Objectives. To evaluate substance P (SP) and the effect of ketoprofen administration, a nonsteroidal anti-inflammatory drug (NSAID), on SP in the pulp of upper third molars with experimentally induced pulpal lesion. Materials and Methods. A sample of 20 young systemically healthy adults of both sexes, nonsmokers, with a healthy upper third molar to extract for orthodontic purposes, was selected. Prior to the procedure, an inflammatory process was generated by mechanical exposure of the pulp. After 15 minutes, the pulp was collected using a sterile barbed broach. SP levels were determined by using a commercially available enzyme immunoassay (ELISA) kit. The subjects were randomly divided into two groups: group 1 received a dose of ketoprofen 30 minutes prior to the experimental procedure. The subjects of group 2 did not receive any kind of drug administration. The patients were asked to complete a diary on the postoperative pain. Results. No statistically significant difference could be detected in SP expression between the two groups. In group 1, pain manifestation was significantly delayed in comparison with group 2. Conclusions. Preventive administration of ketoprofen did not significantly affect the pulpal levels of SP but resulted in a significantly postponed manifestation of pain after extraction. PMID:27034673

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

    SciTech Connect

    Constantinou, Maria A.; Theocharis, Stamatios E.; Mikros, Emmanuel . E-mail: mikros@pharm.uoa.gr

    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 {sup 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. {sup 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 {sup 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.

  6. Prediction of Symptom Change in Placebo Versus No-Treatment Group in Experimentally Induced Motion Sickness.

    PubMed

    Horing, Bjoern; Weimer, Katja; Muth, Eric R; Enck, Paul

    2015-09-01

    The long-standing question of who responds to placebo and who does not is of great theoretical and clinical relevance and has received increasing attention in recent years. We therefore performed a post hoc analysis of one of our previously published studies on placebo responses (PRs). In the analysis, fourteen potential predictors for the PR on experimentally induced motion sickness in 32 healthy volunteers were explored using moderated multiple regression. Generalized self-efficacy, generalized self, internal locus of control and cognitive flexibility were significantly associated with symptom improvement in the placebo group, as compared to the untreated control group. Notably, the directions of the associations were such that the "unfavorable" side of the constructs (e.g. low self-efficacy) predicted a higher PR. Instead, the "favorable" side predicted symptom improvement in the control group. Results fit well with prior research into psychological influences on motion sickness. Although PRs in motion sickness are not well established, it is suggested to include the identified constructs in future research involving motion sickness-related symptoms such as nausea and vertigo. Concerning PRs in general, the results may have implications for clinical as well as experimental research on other symptoms and disorders, such as pain or depression. PMID:25912825

  7. Experimentally induced life-history evolution in a killifish in response to the introduction of guppies.

    PubMed

    Walsh, Matthew R; Reznick, David N

    2011-04-01

    Life-history theory predicts that increased predation on juvenile age/size-classes favors delayed maturation and decreased reproductive investment. Although this theory has received correlative support, experimental tests in nature are rare. In 1976 and 1981, guppies (Poecilia reticulata) were transplanted into localities that previously only contained a killifish, Rivulus hartii. This situation presents an opportunity to experimentally test this life-history prediction because guppies prey upon young Rivulus. We evaluated the response to selection in Rivulus by measuring phenotypic and genotypic divergence between introduction and upstream "control" localities that lack guppies. Contrary to expectations, Rivulus from the introduction sites evolved earlier maturation and increased reproductive investment within 25 years. Such evolutionary changes parallel previous investigations on natural communities of Rivulus, but do not comply with predictions of age/size-specific theory. Guppies also caused reduced densities and increased growth rates of Rivulus, which are hypothesized indirect effects of predation. Additional life-history theories show that changes in density and growth can interact with predator-induced mortality to alter the predicted trajectory of evolution. We discuss how these latter frameworks improve the fit between theory and evolution in Rivulus. PMID:21062280

  8. Innate immune response in experimentally induced bovine intramammary infection with Staphylococcus simulans and S. epidermidis

    PubMed Central

    2011-01-01

    Coagulase-negative staphylococci (CNS) are in several countries the most common bacteria isolated in subclinical mastitis. To investigate the innate immune response of cows to infections with two common mastitis-causing CNS species, Staphylococcus epidermidis and Staphylococcus simulans, experimental intramammary infection was induced in eight cows using a crossover design. The milk somatic cell count (SCC), N-acetyl-β-D-glucosaminidase (NAGase) activity, milk amyloid A (MAA), serum amyloid A (SAA) and proinflammatory cytokines interleukin (IL)-1β, IL-8, and tumor necrosis factor α (TNF-α) were determined at several time points before and after challenge. All cows became infected and showed mild to moderate clinical signs of mastitis. The spontaneous elimination rate of the 16 infections was 31.3%, with no difference between species. Infections triggered a local cytokine response in the experimental udder quarters, but cytokines were not detected in the uninfected control quarters or in systemic circulation. The innate local immune response for S. simulans was slightly stronger, with significantly higher concentrations of IL-1β and IL-8. The IL-8 response could be divided into early, delayed, or combined types of response. The CNS species or persistency of infection was not associated with the type of IL-8 response. No significant differences were seen between spontaneously eliminated or persistent infections. PMID:21414189

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

    PubMed Central

    Martinez, María del Carmen; Ruspini, Silvina Fernanda; Afonso, Susana Graciela; Meiss, Roberto; Buzaleh, Ana Maria

    2015-01-01

    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. PMID:25945334

  10. Experimental confirmation of the scaling theory for noise-induced crises

    SciTech Connect

    Sommerer, J.C.; Ditto, W.L.; Grebogi, C.; Ott, E.; Spano, M.L. Applied Physics Laboratory, Laurel, Maryland 20723 Naval Surface Warfare Center, Silver Spring, Maryland 20903)

    1991-04-15

    We investigate experimentally the scaling of the average time {tau} between intermittent, noise-induced bursts for a chaotic mechanical system near a crisis. The system studied is a periodically driven (frequency {ital f}) magnetoelastic ribbon. Theory predicts that for deterministic crises where {tau} scales as {tau}{similar to}{vert bar}{ital f}{minus}{ital f}{sub {ital c}}{vert bar}{sup {minus}{gamma}} ({ital f}{lt}{ital f}{sub {ital c}}, {ital f}={ital f}{sub {ital c}} at crisis), the characteristic time between noise-induced bursts ({ital f}{ge}{ital f}{sub {ital c}}) should scale as {tau}{similar to}{sigma}{sup {minus}{gamma}}{ital g}({vert bar}{ital f}{minus}{ital f}{sub {ital c}}{vert bar}/{sigma}), where {sigma} is the noise strength and {gamma} is the same in both cases. We determine {gamma} for the low-noise ( deterministic'') system, then add noise and observe that the scaling for {tau} is as predicted.

  11. Cell-specific regulation of Ferroportin transcription following experimentally-induced acute anemia in mice.

    PubMed

    Chiabrando, Deborah; Fiorito, Veronica; Marro, Samuele; Silengo, Lorenzo; Altruda, Fiorella; Tolosano, Emanuela

    2013-01-01

    Ferroportin (FPN), the sole characterized iron exporter, is mainly controlled by the peptide hormone hepcidin in response to iron, erythroid factors, hypoxia, and inflammation. In addition, intracellular iron level controls FPN translation by modulating the binding of Iron Responsive Proteins at the 5'UTR of FPN mRNA. Recently, hypoxia inducible factor (HIF)2α has been shown to regulate FPN expression in intestinal cells. Here we show that, during experimentally-induced acute anemia in mice, FPN is regulated at transcriptional level in a cell-specific manner. FPN mRNA level increases in duodenum and spleen macrophages, whereas it does not change in liver and is strongly down-regulated in erythroid precursors. These results were confirmed in Caco2, Raw264.7 and K562 cells treated with a hypoxic stimulus. Moreover, we found a differential expression of HIF1α and HIF2α in cells and tissues that might account for the specificity of FPN regulation. Thus, hypoxia, by directly controlling hepcidin and its target FPN, orchestrates a complex regulatory network aimed at ensuring rapid iron recovery from the periphery and efficient iron utilization in the erythroid compartment.

  12. Antitussive effect of naringin on experimentally induced cough in Guinea pigs.

    PubMed

    Gao, Sen; Li, Peibo; Yang, Hongliang; Fang, Siqi; Su, Weiwei

    2011-01-01

    The mechanism of action of naringin has been investigated in different models of experimentally induced cough in guinea pigs. In contrast to codeine phosphate (6 mg/kg, intravenous administration [i. v.]), naringin (15, 30, and 60 mg/kg, i. v.) had no central antitussive effect on cough elicited by electrical stimulation of the superior laryngeal nerve. Naringin (0.5, 1.0, and 2.0 µmol) could not prevent the cough reflex induced by stimulation of the trachea after intracerebroventricular injection (i. c. v.), while codeine phosphate (0.5 µmol) was highly effective. Further characterizing the peripheral mechanism of naringin, we found that its effect (50 mg/kg, i. v.) was not affected by the depletion of sensory neuropeptides, whereas levodropropizine (10 mg/kg, i. v.) lost its capacity to prevent cough in the capsaicin-desensitized guinea pig. Furthermore, pretreatment with glibenclamide (10 mg/kg, intraperitoneal [i. p.]) significantly reduced the antitussive effect of pinacidil (5 mg/kg, subcutaneous [s. c.]), but could not antagonize the antitussive effect of naringin (30 mg/kg, s. c.). Our present results suggest that naringin is not a central antitussive drug. And naringin does not exert its peripheral antitussive effect through either the sensory neuropeptides system or the modulation of ATP-sensitive K (+) channels.

  13. Low-Dose IL-2 Induces Regulatory T Cell-Mediated Control of Experimental Food Allergy.

    PubMed

    Bonnet, Benjamin; Vigneron, James; Levacher, Béatrice; Vazquez, Thomas; Pitoiset, Fabien; Brimaud, Faustine; Churlaud, Guillaume; Klatzmann, David; Bellier, Bertrand

    2016-07-01

    Regulatory T cells (Tregs) are pivotal for maintenance of immune self-tolerance and also regulate immune responses to exogenous Ags, including allergens. Both decreased Treg number and function have been reported in allergic patients, offering new therapeutic perspectives. We previously demonstrated that Tregs can be selectively expanded and activated by low doses of IL-2 (ld-IL-2) inducing immunoregulation without immunosuppression and established its protective effect in autoimmune diseases. In this study, we evaluated the ability of ld-IL-2 to control allergy in an experimental model of food allergy. Ld-IL-2 induced Treg expansion and activation that elicited protection against clinical manifestations of food allergy in two mouse models with OVA and peanut. This clinical effect was lost in Treg-depleted mice, demonstrating the major contribution of Tregs in ld-IL-2 efficacy. Mechanistic studies further indicated that protection from allergy could be explained by a Treg-dependent local modification of the Th1/Th2 balance and an inhibition of mast cell recruitment and activation. Preventive and therapeutic effects of ld-IL-2 were observed over a 7-mo-period, highlighting its long-term efficacy. This study demonstrated that ld-IL-2 is efficient to prevent and to treat allergic immune responses, and thus represents a promising therapeutic strategy for managing allergic diseases. PMID:27259854

  14. Plasmepsin 4-Deficient Plasmodium berghei Are Virulence Attenuated and Induce Protective Immunity against Experimental Malaria

    PubMed Central

    Spaccapelo, Roberta; Janse, Chris J.; Caterbi, Sara; Franke-Fayard, Blandine; Bonilla, J. Alfredo; Syphard, Luke M.; Di Cristina, Manlio; Dottorini, Tania; Savarino, Andrea; Cassone, Antonio; Bistoni, Francesco; Waters, Andrew P.; Dame, John B.; Crisanti, Andrea

    2010-01-01

    Plasmodium parasites lacking plasmepsin 4 (PM4), an aspartic protease that functions in the lysosomal compartment and contributes to hemoglobin digestion, have only a modest decrease in the asexual blood-stage growth rate; however, PM4 deficiency in the rodent malaria parasite Plasmodium berghei results in significantly less virulence than that for the parental parasite. P. berghei Δpm4 parasites failed to induce experimental cerebral malaria (ECM) in ECM-susceptible mice, and ECM-resistant mice were able to clear infections. Furthermore, after a single infection, all convalescent mice were protected against subsequent parasite challenge for at least 1 year. Real-time in vivo parasite imaging and splenectomy experiments demonstrated that protective immunity acted through antibody-mediated parasite clearance in the spleen. This work demonstrates, for the first time, that a single Plasmodium gene disruption can generate virulence-attenuated parasites that do not induce cerebral complications and, moreover, are able to stimulate strong protective immunity against subsequent challenge with wild-type parasites. Parasite blood-stage attenuation should help identify protective immune responses against malaria, unravel parasite-derived factors involved in malarial pathologies, such as cerebral malaria, and potentially pave the way for blood-stage whole organism vaccines. PMID:20019192

  15. In vivo microtubule dynamics during experimentally induced conversions between tubulin assembly states in Allogromia laticollaris.

    PubMed

    Welnhofer, E A; Travis, J L

    1996-01-01

    A distinctive property of foraminiferan tubulin is that, in addition to microtubules (MTs), it exists in an alternate assembly state, helical filaments. Here, we have examined in vivo MT dynamics during experimentally induced conversions between these two assembly states in the reticulopods of the marine foraminiferan Allogromia laticollaris. Exposure to high extracellular concentrations of Mg2+ (165 mM) resulted in a complete conversion of MTs into helical filaments. However, Mg2+ treatment also induced a retrograde movement of organelles and cytoplasm, and it was necessary to inhibit this response in order to assess the effects of assembly state changes on individual MTs. This was accomplished by simultaneous treatment with high extracellular Mg2+ and 2,4-dinitrophenol (DNP). The resulting loss in MTs was detected by video enhanced DIC (VEC-DIC) microscopy as either an endwise MT shortening (at an average rate of 474 microns/min) or transformation into one or more irregularly shaped fibrils, which we termed residual fibrils. Correlative immunofluorescence and video microscopy showed residual fibrils to be composed of helical filaments. Removal of extracellular Mg2+/DNP initiated a reversal in assembly state, from helical filaments into MTs, which was completed within 5 min. VEC-DIC microscopy showed that MTs reformed by an endwise lengthening at an average rate of 216 microns/min. These results suggest that conversion between alternate tubulin assembly states provides a more rapid means to build and dismantle MTs than conventional subunit-driven pathways.

  16. Critical role of activation induced cytidine deaminase in experimental autoimmune encephalomyelitis.

    PubMed

    Sun, Yonglian; Peng, Ivan; Senger, Kate; Hamidzadeh, Kajal; Reichelt, Mike; Baca, Miriam; Yeh, Ronald; Lorenzo, Maria N; Sebrell, Andrew; Dela Cruz, Christopher; Tam, Lucinda; Corpuz, Racquel; Wu, Jiansheng; Sai, Tao; Roose-Girma, Merone; Warming, Søren; Balazs, Mercedesz; Gonzalez, Lino C; Caplazi, Patrick; Martin, Flavius; Devoss, Jason; Zarrin, Ali A

    2013-03-01

    Multiple Sclerosis (MS) is a neurodegenerative autoimmune disorder caused by chronic inflammation and demyelination within the central nervous system (CNS). Clinical studies in MS patients have demonstrated efficacy with B cell targeted therapies such as anti-CD20. However, the exact role that B cells play in the disease process is unclear. Activation Induced cytidine deaminase (AID) is an essential enzyme for the processes of antibody affinity maturation and isotype switching. To evaluate the impact of affinity maturation and isotype switching, we have interrogated the effect of AID-deficiency in an animal model of MS. Here, we show that the severity of experimental autoimmune encephalomyelitis (EAE) induced by the extracellular domain of human myelin oligodendrocyte glycoprotein (MOG1-125) is significantly reduced in Aicda deficient mice, which, unlike wild-type mice, lack serum IgG to myelin associated antigens. MOG specific T cell responses are comparable between wild-type and Aicda knockout mice suggesting an active role for antigen experienced B cells. Thus affinity maturation and/or class switching are critical processes in the pathogenesis of EAE. PMID:23167594

  17. Critical role of activation induced cytidine deaminase in Experimental Autoimmune Encephalomyelitis

    PubMed Central

    2013-01-01

    Multiple Sclerosis (MS) is a neurodegenerative autoimmune disorder caused by chronic inflammation and demyelination within the central nervous system (CNS). Clinical studies in MS patients have demonstrated efficacy with B cell targeted therapies such as anti-CD20. However, the exact role that B cells play in the disease process is unclear. Activation Induced cytidine deaminase (AID) is an essential enzyme for the processes of antibody affinity maturation and isotype switching. To evaluate the impact of affinity maturation and isotype switching, we have interrogated the effect of AID-deficiency in an animal model of MS. Here, we show that the severity of experimental autoimmune encephalomyelitis (EAE) induced by the extracellular domain of human myelin oligodendrocyte glycoprotein (MOG1-125) is significantly reduced in Aicda deficient mice, which, unlike wild-type mice, lack serum IgG to myelin associated antigens. MOG specific T cell responses are comparable between wild-type and Aicda knockout mice suggesting an active role for antigen experienced B cells. Thus affinity maturation and/or class switching are critical processes in the pathogenesis of EAE. PMID:23167594

  18. Exploring the electron density in plasma induced by EUV radiation: I. Experimental study in hydrogen

    NASA Astrophysics Data System (ADS)

    van der Horst, R. M.; Beckers, J.; Osorio, E. A.; Astakhov, D. I.; Goedheer, W. J.; Lee, C. J.; Ivanov, V. V.; Krivtsum, V. M.; Koshelev, K. N.; Lopaev, D. V.; Bijkerk, F.; Banine, V. Y.

    2016-04-01

    Plasmas induced by EUV radiation are unique since they are created without the need of any discharge. Moreover, it is essential to characterize these plasmas to understand and predict their long term impact on highly delicate optics in EUV lithography tools. In this paper we study plasmas induced by 13.5 nm EUV radiation in hydrogen gas. The electron density is measured temporally resolved using a non-invasive technique known as microwave cavity resonance spectroscopy. The influence of the EUV pulse energy and gas pressure on the temporal evolution of the electron density has been explored over a parameter range relevant for industry. Our experimental results show that the maximum electron density is in the order of 1014 m-3 and depends linearly on the EUV pulse energy. Furthermore, the maximum electron density depends quadratically on the pressure; the linear term is caused by photoionization and the quadratic term by subsequent electron impact ionization. The decay of the plasma is governed by ambipolar diffusion and, hence, becomes slower at elevated pressures. Similarities and differences of the same processes in argon are highlighted in this paper.

  19. Extract of Sesbania grandiflora Ameliorates Hyperglycemia in High Fat Diet-Streptozotocin Induced Experimental Diabetes Mellitus

    PubMed Central

    Panigrahi, Ghanshyam; Panda, Chhayakanta; Patra, Arjun

    2016-01-01

    Background. Sesbania grandiflora has been traditionally used as antidiabetic, antioxidant, antipyretic, and expectorant and in the management of various ailments. Materials and Methods. The study evaluates the antidiabetic activity of methanolic extract of Sesbania grandiflora (MESG) in type 2 diabetic rats induced by low dose streptozotocine and high fat diet. Diabetic rats were given vehicle, MESG (200 and 400 mg/kg, p.o.), and the standard drug, metformin (10 mg/kg), for 28 days. During the experimental period, body weight, abdominal girth, food intake, fasting serum glucose, urine analyses were measured. Insulin tolerance test was carried out on 25th day of drug treatment period. Serum analyses for lipid profile and SGOT and SGPT and serums creatinine, urea, protein, SOD, and MDA were also carried out. At the end of the experiment, animals were euthanized, the liver and pancreas were immediately dissected out, and the ratio of pancreas to body weight and hepatic glycogen were calculated. Results. MESG (200 and 400 mg/kg, p.o.) induced significant reduction (P < 0.05) of raised blood glucose levels in diabetic rats and also restored other parameters to normal level. Conclusion. Therefore, it is concluded that MESG has potential antihyperglycemic and antihyperlipemic activities and alleviate insulin resistance conditions. PMID:27313954

  20. Ocimum sanctum Linn. leaf extracts inhibit acetylcholinesterase and improve cognition in rats with experimentally induced dementia.

    PubMed

    Giridharan, Vijayasree Vayalanellore; Thandavarayan, Rajarajan Amirthalingam; Mani, Vasudevan; Ashok Dundapa, Taranalli; Watanabe, Kenichi; Konishi, Tetsuya

    2011-09-01

    Cognitive disorders such as dementia, attention deficits, and Alzheimer's disease (AD) have been well investigated. However, effective interventions for the promotion and progression of AD are unavailable to date. The present work was undertaken to investigate the effects of the aqueous (300 and 500 mg/kg) and alcoholic (300 and 500 mg/kg) extracts of Ocimum sanctum Linn. leaves as an antidementic and anticholinesterase agent and also as an immunostimulant in rats. Maximal electroshock, atropine, and cyclosporine were used to induce dementia. The passive avoidance task was used for assessing memory. Acetylcholinesterase (AChE) activity was estimated in different parts of the brain, and immune status was studied using dinitrochlorobenzene (DNCB) skin sensitivity tests. In all the three models both aqueous and alcoholic O. sanctum extracts decreased the time taken to reach the shock-free zone and the number of mistakes and significantly decreased the AChE activity in rats. O. sanctum treatment significantly increased the induration in the DNCB skin test. Therefore, O. sanctum was shown to be useful for the management of experimentally induced cognitive dysfunctions in rats.

  1. Prevention of chemically induced diabetes mellitus in experimental animals by virgin argan oil.

    PubMed

    Bellahcen, Said; Mekhfi, Hassane; Ziyyat, Abderrahim; Legssyer, Abdelkhaleq; Hakkou, Abdelkader; Aziz, Mohammed; Bnouham, Mohamed

    2012-02-01

    The argan tree plays an important socioeconomic and ecologic role in South Morocco. Moreover, there is much evidence for the beneficial effects of virgin argan oil (VAO) on human health. Thus, this study investigated whether administering VAO to rats can prevent the development of diabetes. VAO extracted by a traditional method from the almonds of Argania spinosa (2 mL/kg) was administered orally (for 7 consecutive days) to rats before and during intraperitoneal alloxan administration (75 mg/kg for 5 consecutive days). An alloxan diabetic-induced untreated group and treated by table oil were used as control groups. Body mass, blood glucose and hepatic glycogen were evaluated. In the present study, subchronic treatment with VAO at a dose of 2 mL/kg, before the experimental induction of diabetes, prevented the body mass loss, induced a significant reduction of blood glucose and a significant increase of hepatic glycogen level (p < 0.001) compared with the untreated diabetic group. In conclusion, the present study shows that argan oil should be further investigated in a human study to clarify its possible role in reducing weight loss in diabetics, and even in inhibiting the development or progression of diabetes. This antidiabetic effect could be due to the richness of VAO in tocopherols, phenolic compounds and unsaturated fatty acids. PMID:21584872

  2. Effect of Gmelina arborea Roxb in experimentally induced inflammation and nociception

    PubMed Central

    Kulkarni, Yogesh A.; Panjabi, Ritesh; Patel, Vishvas; Tawade, Aditi; Gokhale, Alok

    2013-01-01

    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. PMID:24250144

  3. Prevention of chemically induced diabetes mellitus in experimental animals by virgin argan oil.

    PubMed

    Bellahcen, Said; Mekhfi, Hassane; Ziyyat, Abderrahim; Legssyer, Abdelkhaleq; Hakkou, Abdelkader; Aziz, Mohammed; Bnouham, Mohamed

    2012-02-01

    The argan tree plays an important socioeconomic and ecologic role in South Morocco. Moreover, there is much evidence for the beneficial effects of virgin argan oil (VAO) on human health. Thus, this study investigated whether administering VAO to rats can prevent the development of diabetes. VAO extracted by a traditional method from the almonds of Argania spinosa (2 mL/kg) was administered orally (for 7 consecutive days) to rats before and during intraperitoneal alloxan administration (75 mg/kg for 5 consecutive days). An alloxan diabetic-induced untreated group and treated by table oil were used as control groups. Body mass, blood glucose and hepatic glycogen were evaluated. In the present study, subchronic treatment with VAO at a dose of 2 mL/kg, before the experimental induction of diabetes, prevented the body mass loss, induced a significant reduction of blood glucose and a significant increase of hepatic glycogen level (p < 0.001) compared with the untreated diabetic group. In conclusion, the present study shows that argan oil should be further investigated in a human study to clarify its possible role in reducing weight loss in diabetics, and even in inhibiting the development or progression of diabetes. This antidiabetic effect could be due to the richness of VAO in tocopherols, phenolic compounds and unsaturated fatty acids.

  4. Role of neurosteroids in experimental 3-nitropropionic acid induced neurotoxicity in rats.

    PubMed

    Kumar, Pushpender; Kumar, Puneet; Khan, Aamir; Deshmukh, Rahul; Lal Sharma, Pyare

    2014-01-15

    Huntington's disease is an autosomal dominant, progressive, and fatal neurodegenerative disease characterized by motor and non-motor symptoms. Systemic administration of 3-nitropropionic acid, a complex II inhibitor of the electron transport chain induces selective striatal lesions in rodents. Neurosteroids are synthesized in central nervous system, able to modulate GABAA receptor function and has been reported to have neuroprotective action. The present study has been designed to investigate the role of neurosteroids such as progesterone and pregnenolone which are positive and negative modulators of GABA respectively against 3-nitropropionic acid induced experimental Huntington's disease. Systemic administration of 3-nitropropionic acid (10mg/kg i.p.) for 14 days significantly reduced body weight, locomotor activity, motor coordination, balance beam walk performance, antioxidant defense enzymes (reduced glutathione and catalase) and significantly increase oxidative stress markers (lipid peroxidation and nitrite level) in striatum and cortex. 3-Nitropropionic acid treatment also increases pro-inflammatory cytokines (TNF-α and IL-1β) level in striatum. Progesterone (10, 20mg/kg/day i.p.) treatments for 14 days significantly reversed the behavioral, antioxidant defense enzymes, oxidative stress marker and pro-inflammatory cytokines as compared to the 3-Nitropropionic acid treated group. Pregnenolone (1 and 2mg/kg i.p.), a negative modulator of GABAA pretreatment significantly reversed the protective effect of progesterone on behavioral and biochemical parameters. The results of the present study suggest that the positive GABAergic modulation may be beneficial for the treatment of motor disorder. PMID:24333475

  5. Extract of Sesbania grandiflora Ameliorates Hyperglycemia in High Fat Diet-Streptozotocin Induced Experimental Diabetes Mellitus.

    PubMed

    Panigrahi, Ghanshyam; Panda, Chhayakanta; Patra, Arjun

    2016-01-01

    Background. Sesbania grandiflora has been traditionally used as antidiabetic, antioxidant, antipyretic, and expectorant and in the management of various ailments. Materials and Methods. The study evaluates the antidiabetic activity of methanolic extract of Sesbania grandiflora (MESG) in type 2 diabetic rats induced by low dose streptozotocine and high fat diet. Diabetic rats were given vehicle, MESG (200 and 400 mg/kg, p.o.), and the standard drug, metformin (10 mg/kg), for 28 days. During the experimental period, body weight, abdominal girth, food intake, fasting serum glucose, urine analyses were measured. Insulin tolerance test was carried out on 25th day of drug treatment period. Serum analyses for lipid profile and SGOT and SGPT and serums creatinine, urea, protein, SOD, and MDA were also carried out. At the end of the experiment, animals were euthanized, the liver and pancreas were immediately dissected out, and the ratio of pancreas to body weight and hepatic glycogen were calculated. Results. MESG (200 and 400 mg/kg, p.o.) induced significant reduction (P < 0.05) of raised blood glucose levels in diabetic rats and also restored other parameters to normal level. Conclusion. Therefore, it is concluded that MESG has potential antihyperglycemic and antihyperlipemic activities and alleviate insulin resistance conditions. PMID:27313954

  6. Antitussive effect of naringin on experimentally induced cough in Guinea pigs.

    PubMed

    Gao, Sen; Li, Peibo; Yang, Hongliang; Fang, Siqi; Su, Weiwei

    2011-01-01

    The mechanism of action of naringin has been investigated in different models of experimentally induced cough in guinea pigs. In contrast to codeine phosphate (6 mg/kg, intravenous administration [i. v.]), naringin (15, 30, and 60 mg/kg, i. v.) had no central antitussive effect on cough elicited by electrical stimulation of the superior laryngeal nerve. Naringin (0.5, 1.0, and 2.0 µmol) could not prevent the cough reflex induced by stimulation of the trachea after intracerebroventricular injection (i. c. v.), while codeine phosphate (0.5 µmol) was highly effective. Further characterizing the peripheral mechanism of naringin, we found that its effect (50 mg/kg, i. v.) was not affected by the depletion of sensory neuropeptides, whereas levodropropizine (10 mg/kg, i. v.) lost its capacity to prevent cough in the capsaicin-desensitized guinea pig. Furthermore, pretreatment with glibenclamide (10 mg/kg, intraperitoneal [i. p.]) significantly reduced the antitussive effect of pinacidil (5 mg/kg, subcutaneous [s. c.]), but could not antagonize the antitussive effect of naringin (30 mg/kg, s. c.). Our present results suggest that naringin is not a central antitussive drug. And naringin does not exert its peripheral antitussive effect through either the sensory neuropeptides system or the modulation of ATP-sensitive K (+) channels. PMID:20645246

  7. Experimentally induced sickness decreases food intake, but not hoarding, in Siberian hamsters (Phodopus sungorus).

    PubMed

    Durazzo, Alfredo; Proud, Kevin; Demas, Gregory E

    2008-11-01

    A wide range of physiological and behavioral alterations occur in response to sickness. Sickness behaviors, rather than incidental by-products or side-effects of acute illness, serve as adaptive functional responses that allow animals to cope with a pathogenic challenge. Among the more salient sickness behaviors is a reduction in food intake; virtually all sick animals display marked decreases in this behavior. Food intake, however, is only one component of the food-related behavioral repertoire. For many mammalian species, food hoarding represents a substantial portion of the total energetic budget. Here we tested the effects of experimental sickness on food hoarding and food intake in a naturally food hoarding species, Siberian hamsters (Phodopus sungorus). Adult male and female hamsters received injections of lipopolysaccharide (LPS) to induce sickness or control injections. LPS-induced sickness resulted in a marked decrease in food intake in both males and females, but did not decrease hoarding in either sex. These results support previous findings suggesting that food hoarding and food intake appear to be differentially regulated at the physiological level.

  8. Changes and significance of IL-25 in chicken collagen II-induced experimental arthritis (CIA).

    PubMed

    Kaiwen, Wang; Zhaoliang, Su; Yinxia, Zhao; Siamak, Sandoghchian Shotorbani; Zhijun, Jiao; Yuan, Xue; Heng, Yang; Dong, Zheng; Yanfang, Liu; Pei, Shen; Shengjun, Wang; Qixiang, Shao; Xinxiang, Huang; Liwei, Lu; Huaxi, Xu

    2012-08-01

    Rheumatoid arthritis (RA) is an autoimmune inflammatory disease. It is a systemic inflammatory disease, characterized by chronic, symmetrical, multi-articular synovial arthritis. IL-25 (IL-17E) is a member of the recently emerged cytokine family (IL-17s), which is expressed in Th2 cells and bone marrow-derived mast cells. Unlike the other members of this family, IL-25 is capable of inducing Th2-associated cytokines (IL-4, IL-5, and IL-13) and also promotes the release of some pro-immune factors (IL-6 and IL-8). IL-25 is also a pleiotropic factor, which constitutes a tissue-specific pathological injury and chronic inflammation. In this study, we used chicken collagen II-induced experimental arthritis (CIA) model in DBA/1 mice to investigate the relationship between IL-25 and other inflammatory factors, revealing the possible mechanism in CIA. Our results showed that the expression level of IL-25 was enhanced in the late stage of CIA, and IL-17 was increased in the early stage of the disease. It is well known that IL-17 has a crucial role in the development of RA pathogenesis, and IL-25 plays a significant role in humoral immune. For reasons given above, we suggested that the IL-25 inhibited IL-17 expression to some extent, while enhancing the production of IL-4. It was confirmed that IL-25 not only regulated the cellular immune, but also involved the humoral immune in rheumatoid arthritis.

  9. Clinical and hematologic variables in ponies with experimentally induced equine ehrlichial colitis (Potomac horse fever).

    PubMed

    Ziemer, E L; Whitlock, R H; Palmer, J E; Spencer, P A

    1987-01-01

    The clinical and hematologic variables of 10 ponies with experimentally induced equine ehrlichial colitis (EEC; syn: Potomac horse fever) were studied for a 30-day period (6 ponies) or until death (4 ponies). The earliest clinical sign indicative of EEC was fever (rectal temperature exceeding 39 C). All ponies became depressed (CNS) at various times during the disease, and 90% of the ponies developed diarrhea between 9 and 15 days after infection was induced. The most significant hematologic change was an increase in plasma protein concentration after the onset of fever (P less than 0.05). The PCV in all ponies became increased above base line during the diarrheic phase of EEC. Forty percent of the ponies developed anemia (PCV less than or equal to 23%) during the study. White blood cell counts were highly variable, with 80% of the ponies developing leukopenia (WBC less than 5,000/microliters) during the illness and 60% of the ponies developing leukocytosis (WBC greater than 14,000/microliters) after leukopenia was observed. Differential WBC changes varied widely and included neutropenia with a left shift, lymphopenia, and eosinopenia. Serial thrombocyte counts, which were done for only 1 pony, identified the development of marked thrombocytopenia. Some hematologic changes in ponies with EEC were similar to those reported in canine monocytic and equine granulocytic ehrlichioses. These data are discussed in the context of the pathogenesis and differential diagnosis of EEC.

  10. The Complement Anaphylatoxin C5a Induces Apoptosis in Adrenomedullary Cells during Experimental Sepsis

    PubMed Central

    Flierl, Michael A.; Rittirsch, Daniel; Chen, Anthony J.; Nadeau, Brian A.; Day, Danielle E.; Sarma, J. Vidya; Huber-Lang, Markus S.; Ward, Peter A.

    2008-01-01

    Sepsis remains a poorly understood, enigmatic disease. One of the cascades crucially involved in its pathogenesis is the complement system. Especially the anaphylatoxin C5a has been shown to have numerous harmful effects during sepsis. We have investigated the impact of high levels of C5a on the adrenal medulla following cecal ligation and puncture (CLP)-induced sepsis in rats as well as the role of C5a on catecholamine production from pheochromocytoma-derived PC12 cells. There was significant apoptosis of adrenal medulla cells in rats 24 hrs after CLP, as assessed by the TUNEL technique. These effects could be reversed by dual-blockade of the C5a receptors, C5aR and C5L2. When rats were subjected to CLP, levels of C5a and norepinephrine were found to be antipodal as a function of time. PC12 cell production of norepinephrine and dopamine was significantly blunted following exposure to recombinant rat C5a in a time-dependent and dose-dependent manner. This impaired production could be related to C5a-induced initiation of apoptosis as defined by binding of Annexin V and Propidium Iodine to PC12 cells. Collectively, we describe a C5a-dependent induction of apoptotic events in cells of adrenal medulla in vivo and pheochromocytoma PC12 cells in vitro. These data suggest that experimental sepsis induces apoptosis of adrenomedullary cells, which are responsible for the bulk of endogenous catecholamines. Septic shock may be linked to these events. Since blockade of both C5a receptors virtually abolished adrenomedullary apoptosis in vivo, C5aR and C5L2 become promising targets with implications on future complement-blocking strategies in the clinical setting of sepsis. PMID:18648551

  11. Computational and experimental analysis of TMS-induced electric field vectors critical to neuronal activation

    NASA Astrophysics Data System (ADS)

    Krieg, Todd D.; Salinas, Felipe S.; Narayana, Shalini; Fox, Peter T.; Mogul, David J.

    2015-08-01

    Objective. Transcranial magnetic stimulation (TMS) represents a powerful technique to noninvasively modulate cortical neurophysiology in the brain. However, the relationship between the magnetic fields created by TMS coils and neuronal activation in the cortex is still not well-understood, making predictable cortical activation by TMS difficult to achieve. Our goal in this study was to investigate the relationship between induced electric fields and cortical activation measured by blood flow response. Particularly, we sought to discover the E-field characteristics that lead to cortical activation. Approach. Subject-specific finite element models (FEMs) of the head and brain were constructed for each of six subjects using magnetic resonance image scans. Positron emission tomography (PET) measured each subject’s cortical response to image-guided robotically-positioned TMS to the primary motor cortex. FEM models that employed the given coil position, orientation, and stimulus intensity in experimental applications of TMS were used to calculate the electric field (E-field) vectors within a region of interest for each subject. TMS-induced E-fields were analyzed to better understand what vector components led to regional cerebral blood flow (CBF) responses recorded by PET. Main results. This study found that decomposing the E-field into orthogonal vector components based on the cortical surface geometry (and hence, cortical neuron directions) led to significant differences between the regions of cortex that were active and nonactive. Specifically, active regions had significantly higher E-field components in the normal inward direction (i.e., parallel to pyramidal neurons in the dendrite-to-axon orientation) and in the tangential direction (i.e., parallel to interneurons) at high gradient. In contrast, nonactive regions had higher E-field vectors in the outward normal direction suggesting inhibitory responses. Significance. These results provide critical new

  12. Differential effects of experimentally induced chronic pancreatitis on neuropeptide immunoreactivities in the feline pancreas.

    PubMed

    De Giorgio, R; Sternini, C; Widdison, A L; Alvarez, C; Brecha, N C; Reber, H A; Go, V L

    1993-11-01

    The distribution and concentration of calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY), and gastrin-releasing peptide (GRP) immunoreactivities in the pancreas of cats with experimentally induced chronic pancreatitis and of age- and sex-matched controls were investigated. By narrowing the main pancreatic duct between the head and the body to approximately 25% of its normal diameter, we induced within 5 weeks chronic pancreatitis restricted to the body and tail. In control animals, peptide immunoreactive nerves were distributed to the islets, acini, and ducts; the latter were predominantly innervated by fibers immunoreactive for NPY, VIP, or CGRP. The vasculature received an abundant supply of NPY-, CGRP-, and, to a lesser extent, SP-containing axons. Within intrapancreatic ganglia, peptide immunoreactivities were identified in fibers and ganglion cells, with the exception of CGRP and SP immunostaining, which could be visualized only in fibers. In animals with chronic pancreatitis, the innervation pattern of each peptidergic system was comparable to that described in controls. However, there was a remarkable increase in the density and staining intensity of VIP and NPY immunoreactive fibers in the exocrine parenchyma and fibrous septa of the body and tail, where chronic pancreatitis developed. Fibers immunoreactive for CGRP and SP also were moderately denser than in controls, whereas those containing GRP immunoreactivity did not show any detectable changes. In addition, a marked increase of the immunostaining for VIP and, to a much lesser extent, for NPY and GRP, was observed in neurites supplying the head of the pancreas, which appeared devoid of histologically detectable pathological alterations. Radioimmunoassay analysis confirmed the immunohistochemical observations. The increased density of distinct peptidergic nerves in the pancreas with induced chronic pancreatitis might be the result of

  13. Androgen- and Estrogen-Receptor Content in Spontaneous and Experimentally Induced Canine Prostatic Hyperplasia

    PubMed Central

    Trachtenberg, John; Hicks, L. Louise; Walsh, Patrick C.

    1980-01-01

    To gain insight into the mechanism by which steroidal hormones influence the development of canine prostatic hyperplasia, nuclear and cytosolic androgen- and estrogen-receptor content, as measured under exchange conditions by the binding of [3H]R1881 (methyltrienolone) and [3H]estradiol, respectively, were quantitated in the prostates of purebred beagles of known age. In young dogs with spontaneously arising and experimentally induced (androstanediol plus estradiol treatment) prostatic hyperplasia, nuclear, but not cytosolic, prostatic androgen-receptor content was significantly greater than that determined in the normal prostates of age-matched dogs (3,452±222 and 4,035±274 fmol/mg DNA vs. 2,096±364 fmol/mg DNA, respectively). No differences were observed between the androgen-receptor content of the normal prostates of young dogs and the hyperplastic prostates of old dogs. The cytosolic and nuclear estrogen-receptor content of spontaneously arising prostatic hyperplasia in both young and old animals was similar to that found in normal prostates. The administration of estradiol plus androstanediol to castrate dogs significantly increased the prostatic nuclear androgen-receptor content over that found in dogs treated only with androstanediol. This estradiol-associated increase in nuclear androgen-receptor content was accompanied by the development of benign prostatic hyperplasia. Estradiol treatment of castrate dogs resulted in an increase in prostatic nuclear estrogen-receptor content, in the appearance of a putative prostatic cytosolic progesterone receptor, and in an alteration of the epithelium of the prostate to one characterized by squamous metaplasia. Treatment of castrate dogs with both estradiol and androstanediol resulted in a reduction in prostatic nuclear estrogen-receptor content, disappearance of the progesterone receptor, and loss of squamous metaplasia. An increase in nuclear androgen-receptor content, thus, appears to be an important event in the

  14. The effect of spinal manipulative therapy on experimentally induced pain: a systematic literature review

    PubMed Central

    2012-01-01

    Background Although there is evidence that spinal manipulative therapy (SMT) can reduce pain, the mechanisms involved are not well established. There is a need to review the scientific literature to establish the evidence-base for the reduction of pain following SMT. Objectives To determine if SMT can reduce experimentally induced pain, and if so, if the effect is i) only at the level of the treated spinal segment, ii) broader but in the same general region as SMT is performed, or iii) systemic. Design A systematic critical literature review. Methods A systematic search was performed for experimental studies on healthy volunteers and people without chronic syndromes, in which the immediate effect of SMT was tested. Articles selected were reviewed blindly by two authors. A summary quality score was calculated to indicate level of manuscript quality. Outcome was considered positive if the pain-reducing effect was statistically significant. Separate evidence tables were constructed with information relevant to each research question. Results were interpreted taking into account their manuscript quality. Results Twenty-two articles were included, describing 43 experiments, primarily on pain produced by pressure (n = 27) or temperature (n = 9). Their quality was generally moderate. A hypoalgesic effect was shown in 19/27 experiments on pressure pain, produced by pressure in 3/9 on pain produced by temperature and in 6/7 tests on pain induced by other measures. Second pain provoked by temperature seems to respond to SMT but not first pain. Most studies revealed a local or regional hypoalgesic effect whereas a systematic effect was unclear. Manipulation of a “restricted motion segment” (“manipulable lesion”) seemed not to be essential to analgesia. In relation to outcome, there was no discernible difference between studies with higher vs. lower quality scores. Conclusions These results indicate that SMT has a direct local/regional hypoalgesic effect on

  15. Experimental and Numerical Study of Laser-Induced Forward Transfer Printing of Liquids

    NASA Astrophysics Data System (ADS)

    Brown, Matthew S.

    Laser-induced forward transfer (LIFT) is an emerging high-resolution printing technique, which can deposit a wide range of fluid materials without a nozzle. In this process, a pulsed laser initiates the highly directed expulsion of fluid from a thin donor ink film onto a confined region of an acceptor substrate. Despite being validated as a versatile technique for printing devices, the fundamental mechanisms of the deposition process are still not fully understood. Further investigation of the laser-induced ejection dynamics is necessary in order to motivate new ways in which to optimize and control the printing process. Additionally, the LIFT configuration presents a unique laboratory in which to study novel regimes of fluid dynamics. This thesis presents an in-depth study of the LIFT printing process using a balance of experimental measurement and computational modeling. In the first part, time-resolved imaging is used to investigate the mechanisms responsible for the laser-induced ejection of ink. Fluid ejections driven by a rapidly expanding gas cavity within the ink film are observed and analyzed within the context of similar work on cavitation bubble formation, revealing that the unique geometry and size scale of LIFT invokes novel flow behavior. An alternative mechanism is also observed in which the fluid is ejected by the rapid formation of blister on a polymer layer adjacent to the ink film. The dynamics of the blister expansion and associated ink ejection are analyzed as a function of system properties and processing parameters. In the second part, a computational model of the blister-actuated ejection process is developed and used to study the novel regime of free-surface jetting from thin liquid films. The model is first validated against experimental results. It is then used to develop a fundamental understanding of the ejection process as well as conduct a detailed parametric study on the influence of system parameters on printing performance. These

  16. Comparison of assisted ventilator modes on triggering, patient effort, and dyspnea.

    PubMed

    Leung, P; Jubran, A; Tobin, M J

    1997-06-01

    In 11 ventilator-dependent patients, we undertook a head-to-head comparison of patient-ventilator interaction during four ventilator modes: assist-control ventilation (ACV), intermittent mandatory ventilation (IMV), pressure support (PS), and a combination of IMV and PS. Progressive increases in IMV rate and PS level each decreased inspiratory pressure-time product (PTP) (p < 0.0001). These reductions in PTP were greater with PS than with IMV at lower but proportional levels of maximal assistance (p < 0.005). When PS 10 cm H2O was added to a given level of IMV, greater reductions in PTP were achieved not only during intervening (PS) breaths (p < 0.001), but also during mandatory (volume-assisted) breaths (p < 0.0005); this additional unloading during mandatory breaths was proportional to the decrease in respiratory drive (dP/dt) during intervening breaths (r = 0.67, p < 0.0001). Maximal unloading occurred with ACV, achieving more than a fivefold decrease in PTP compared with unassisted breathing. Decreases in PTP were confined to the post-trigger phase, and PTP of the post-trigger phase correlated with dP/dt (r = 0.78, p < 0.0001). Effort during the trigger phase remained constant despite marked changes in drive and intrinsic positive end-expiratory pressure (PEEPi). Ineffective triggering occurred with all modes, and wasted PTP increased with increasing levels of assistance as a result of the accompanying decrease in drive and increase in volume. Breaths preceding nontriggering efforts had shorter respiratory cycle times (p < 0.0005) and expiratory times (p < 0.0001) and higher PEEPi (p < 0.0001), indicating that neural-mechanical asynchrony resulted from inspiratory activity commencing prematurely before elastic recoil pressure had fallen to a level that could be overcome by a patient's muscular effort. Thus, increases in the level of ventilator assistance produced progressive decreases in inspiratory muscle effort and dyspnea,which were accompanied by increases

  17. Experimental and predicted cavitation performance of an 80.6 deg helical inducer in high temperature water

    NASA Technical Reports Server (NTRS)

    Kovich, G.

    1972-01-01

    The cavitating performance of a stainless steel 80.6 degree flat-plate helical inducer was investigated in water over a range of liquid temperatures and flow coefficients. A semi-empirical prediction method was used to compare predicted values of required net positive suction head in water with experimental values obtained in water. Good agreement was obtained between predicted and experimental data in water. The required net positive suction head in water decreased with increasing temperature and increased with flow coefficient, similar to that observed for a like inducer in liquid hydrogen.

  18. Prognostic Importance of Dyspnea for Cardiovascular Outcomes and Mortality in Persons without Prevalent Cardiopulmonary Disease: The Atherosclerosis Risk in Communities Study

    PubMed Central

    Santos, Mario; Kitzman, Dalane W.; Matsushita, Kunihiro; Loehr, Laura; Sueta, Carla A.; Shah, Amil M.

    2016-01-01

    Background The relationship between dyspnea and incident heart failure (HF) and myocardial infarction (MI) among patients without previously diagnosed cardiopulmonary disease is unclear. We studied the prognostic relevance of self-reported dyspnea for cardiovascular outcomes and all-cause mortality in persons without previously diagnosed cardiopulmonary disease. Methods and Results We studied 10 881 community-dwelling participants (mean age 57±6, 56% women, 25% black) who were free of prevalent cardiopulmonary disease from Atherosclerosis Risk in Communities Study. Dyspnea status at study entry using the modified Medical Research Council (mMRC) scale. The primary outcomes were time to HF, MI or all-cause death. Dyspnea prevalence was 22%, and was mild (mMRC grade 1 or 2) in 21% and moderate-to-severe (mMRC 3 or 4) in 1%. The main correlates of dyspnea were older age, female sex, higher BMI and active smoking. Over a follow-up of 19±5 years, greater self-reported dyspnea severity was associated with worse prognosis. Mild dyspnea was associated with significantly heightened risk of HF (adjusted Hazard Ratio, HR,1.30; 95% CI: 1.16–1.46), MI (adjusted HR 1.34; 95%CI: 1.20–1.50), and death (adjusted HR 1.16; 95%CI: 1.06–1.26), with moderate/severe dyspnea associated with an even greater risk (adjusted HR 2.14, 95%CI: 1.59–2.89; 1.93, 95%CI: 1.41–2.56; 1.96, 95%CI: 1.55–2.48, respectively). Conclusion In community-dwelling persons free of previously diagnosed cardiopulmonary disease, self-reported dyspnea is common and, even when of mild intensity, it is independently associated with a greater risk of incident HF, MI, and death. Our data emphasize the prognostic importance of even mild self-reported dyspnea for cardiovascular outcomes. PMID:27780208

  19. Expectation-induced placebo responses fail to accelerate wound healing in healthy volunteers: results from a prospective controlled experimental trial.

    PubMed

    Vits, Sabine; Dissemond, Joachim; Schadendorf, Dirk; Kriegler, Lisa; Körber, Andreas; Schedlowski, Manfred; Cesko, Elvir

    2015-12-01

    Placebo responses have been shown to affect the symptomatology of skin diseases. However, expectation-induced placebo effects on wound healing processes have not been investigated yet. We analysed whether subjects' expectation of receiving an active drug accelerates the healing process of experimentally induced wounds. In 22 healthy men (experimental group, n = 11; control group, n = 11) wounds were induced by ablative laser on both thighs. Using a deceptive paradigm, participants in the experimental group were informed that an innovative 'wound gel' was applied on one of the two wounds, whereas a 'non-active gel' was applied on the wound of the other thigh. In fact, both gels were identical hydrogels without any active components. A control group was informed to receive a non-active gel on both wounds. Progress in wound healing was documented via planimetry on days 1, 4 and 7 after wound induction. From day 9 onwards wound inspections were performed daily accompanied by a change of the dressing and a new application of the gel. No significant differences could be observed with regard to duration or process of wound healing, either by intraindividual or by interindividual comparisons. These data document no expectation-induced placebo effect on the healing process of experimentally induced wounds in healthy volunteers. PMID:24373522

  20. Expectation-induced placebo responses fail to accelerate wound healing in healthy volunteers: results from a prospective controlled experimental trial.

    PubMed

    Vits, Sabine; Dissemond, Joachim; Schadendorf, Dirk; Kriegler, Lisa; Körber, Andreas; Schedlowski, Manfred; Cesko, Elvir

    2015-12-01

    Placebo responses have been shown to affect the symptomatology of skin diseases. However, expectation-induced placebo effects on wound healing processes have not been investigated yet. We analysed whether subjects' expectation of receiving an active drug accelerates the healing process of experimentally induced wounds. In 22 healthy men (experimental group, n = 11; control group, n = 11) wounds were induced by ablative laser on both thighs. Using a deceptive paradigm, participants in the experimental group were informed that an innovative 'wound gel' was applied on one of the two wounds, whereas a 'non-active gel' was applied on the wound of the other thigh. In fact, both gels were identical hydrogels without any active components. A control group was informed to receive a non-active gel on both wounds. Progress in wound healing was documented via planimetry on days 1, 4 and 7 after wound induction. From day 9 onwards wound inspections were performed daily accompanied by a change of the dressing and a new application of the gel. No significant differences could be observed with regard to duration or process of wound healing, either by intraindividual or by interindividual comparisons. These data document no expectation-induced placebo effect on the healing process of experimentally induced wounds in healthy volunteers.

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

    PubMed Central

    Suojala, Leena; Orro, Toomas; Järvinen, Hanna; Saatsi, Johanna; Pyörälä, Satu

    2008-01-01

    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 induction of the same animals

  2. Schistosoma mansoni Tegument (Smteg) Induces IL-10 and Modulates Experimental Airway Inflammation

    PubMed Central

    2016-01-01

    Background Previous studies have demonstrated that S. mansoni infection and inoculation of the parasite eggs and antigens are able to modulate airways inflammation induced by OVA in mice. This modulation was associated to an enhanced production of interleukin-10 and to an increased number of regulatory T cells. The S. mansoni schistosomulum is the first stage to come into contact with the host immune system and its tegument represents the host-parasite interface. The schistosomula tegument (Smteg) has never been studied in the context of modulation of inflammatory disorders, although immune evasion mechanisms take place in this phase of infection to guarantee the persistence of the parasite in the host. Methodology and Principal Findings The aim of this study was to evaluate the Smteg ability to modulate inflammation in an experimental airway inflammation model induced by OVA and to characterize the immune factors involved in this modulation. To achieve the objective, BALB/c mice were sensitized with ovalbumin (OVA) and then challenged with OVA aerosol after Smteg intraperitoneal inoculation. Protein extravasation and inflammatory cells were assessed in bronchoalveolar lavage and IgE levels were measured in serum. Additionally, lungs were excised for histopathological analyses, cytokine measurement and characterization of the cell populations. Inoculation with Smteg led to a reduction in the protein levels in bronchoalveolar lavage (BAL) and eosinophils in both BAL and lung tissue. In the lung tissue there was a reduction in inflammatory cells and collagen deposition as well as in IL-5, IL-13, IL-25 and CCL11 levels. Additionally, a decrease in specific anti-OVA IgE levels was observed. The reduction observed in these inflammatory parameters was associated with increased levels of IL-10 in lung tissues. Furthermore, Smteg/asthma mice showed high percentage of CD11b+F4/80+IL-10+ and CD11c+CD11b+IL-10+ cells in lungs. Conclusion Taken together, these findings

  3. Effect of sildenafil citrate in nicotine-induced ischemia: An experimental study using a rat model

    PubMed Central

    Baykan, Halit; Ozyazgan, Irfan; Selçuk, Caferi Tayyar; Altiparmak, Mehmet; Özköse, Mehmet; Özyurt, Kemal

    2013-01-01

    Recent experimental and clinical studies have demonstrated the negative effects of nicotine on the viability of skin flaps. Necrotic damage to skin flaps can result in significant complications including delayed wound healing, dehiscence and wound contraction. Phosphodiesterase type 5 inhibitors, such as sildenafil citrate, have a protective effect in ischemic injuries of the brain, kidney, myocardium, spinal cord, ileum and testes. In the present study, the authors evaluated the effect of sildenafil citrate on the viability of skin exposed to nicotine-induced ischemia in Sprague Dawley rats. In the preoperative period, the rats were divided into three groups of 10 rats each. Group C was treated with subcutaneous saline and group S and group N were treated with 2 mg/kg nicotine, administered subcutaneously twice per day for 28 days. McFarlane flaps were created in all experimental animals using an incision measuring 7 cm × 3 cm. Postoperative treatment varied among the groups: group S was treated with 20 mg/kg/day sildenafil citrate, while group C and group N were treated with equivalent doses of saline for seven days. A laser Doppler flow meter was used to monitor the microvasculature. Preoperative measurements of the microvasculature revealed decreased blood flow in group N and group S, both of which were treated with subcutaneous nicotine. During the postoperative evaluation, a trend toward increased blood flow was observed in group S compared with the group with nicotine-induced ischemia treated with saline alone postoperatively (group N). A visual fluorescein dye test was used to predict skin viability and demonstrated diminished skin viability in group N and group S (P<0.05) during the preoperative period. Following treatment with sildenafil for seven days, a statically significant improvement in skin viability was observed in group S (P<0.05). Nicotine decreased blood flow within the skin and impaired skin viability, while postoperative application of

  4. Effect of sildenafil citrate in nicotine-induced ischemia: An experimental study using a rat model.

    PubMed

    Baykan, Halit; Ozyazgan, Irfan; Selçuk, Caferi Tayyar; Altiparmak, Mehmet; Ozköse, Mehmet; Ozyurt, Kemal

    2013-01-01

    Recent experimental and clinical studies have demonstrated the negative effects of nicotine on the viability of skin flaps. Necrotic damage to skin flaps can result in significant complications including delayed wound healing, dehiscence and wound contraction. Phosphodiesterase type 5 inhibitors, such as sildenafil citrate, have a protective effect in ischemic injuries of the brain, kidney, myocardium, spinal cord, ileum and testes. In the present study, the authors evaluated the effect of sildenafil citrate on the viability of skin exposed to nicotine-induced ischemia in Sprague Dawley rats. In the preoperative period, the rats were divided into three groups of 10 rats each. Group C was treated with subcutaneous saline and group S and group N were treated with 2 mg/kg nicotine, administered subcutaneously twice per day for 28 days. McFarlane flaps were created in all experimental animals using an incision measuring 7 cm × 3 cm. Postoperative treatment varied among the groups: group S was treated with 20 mg/kg/day sildenafil citrate, while group C and group N were treated with equivalent doses of saline for seven days. A laser Doppler flow meter was used to monitor the microvasculature. Preoperative measurements of the microvasculature revealed decreased blood flow in group N and group S, both of which were treated with subcutaneous nicotine. During the postoperative evaluation, a trend toward increased blood flow was observed in group S compared with the group with nicotine-induced ischemia treated with saline alone postoperatively (group N). A visual fluorescein dye test was used to predict skin viability and demonstrated diminished skin viability in group N and group S (P<0.05) during the preoperative period. Following treatment with sildenafil for seven days, a statically significant improvement in skin viability was observed in group S (P<0.05). Nicotine decreased blood flow within the skin and impaired skin viability, while postoperative application of

  5. Detection of endothelial nitric oxide synthase and NADPH-diaphorase in experimentally induced hyperoxaluric animals.

    PubMed

    Pragasam, Viswanathan; Sakthivel, Ramasamy; Kalaiselvi, Periyandavan; Rajesh, Nachiappa Ganesh; Varalakshmi, Palaninathan

    2005-08-01

    Nitrosative stress plays a role in calcium oxalate stone formation, as nitrosated proteins have been identified in stone formers. Nitric oxide (NO(*)), the common precursor for reactive nitrogen species, is synthesized in the juxtaglomerular apparatus of the kidneys. The present study is aimed to determine the role of nitric oxide synthase (NOS) in an experimental hyperoxaluric condition by histological and biochemical techniques. Hyperoxaluria was induced by 0.75% ethylene glycol in drinking water. L-arginine (L-arg) was supplemented at a dose of 1.25 g/kg body weight orally for 28 days. Nitric oxide metabolites (NOx), protein content in the urine and lipid peroxidation in the kidney were determined at the end of the experimental period. Histopathological examination of the rat kidneys was then carried out. NADPH-diaphorase and eNOS expression studies were carried out in control and hyperoxaluric rat kidneys using histochemical and immunohistochemical techniques. Significant amounts of NOx were present in the urine of hyperoxaluric animals when compared to control rats. Histopathological examinations revealed membrane injury, tubular dilatation and edema in the hyperoxaluric rats, whereas co-supplementation of L-arg to the hyperoxaluric rats significantly reduced these changes. The results of histochemical analysis for NADPH-diaphorase staining demonstrate the role of NOS in hyperoxaluric rats. Hyperoxaluric rats showed intense staining for NADPH-diaphorase when compared to control and L-arg co-supplemented hyperoxaluric rats. Immunohistochemical demonstration confirmed that eNOS expression was markedly increased in L-arg supplemented rats, when compared to EG treated rat kidney sections. Thus, from the present study, we conclude that supplementation of L-arg to the hyperoxaluric animals minimizes the cellular injury mediated by ethylene glycol, prevents oxidative/nitrosative damage to the membranes and reduces the incidence of calcium oxalate stone formation.

  6. Cellular Mechanisms and Behavioral Outcomes in Blast-Induced Neurotrauma: Comparing Experimental Setups.

    PubMed

    Bailey, Zachary S; Hubbard, W Brad; VandeVord, Pamela J

    2016-01-01

    Blast-induced neurotrauma (BINT) has increased in incidence over the past decades and can result in cognitive issues that have debilitating consequences. The exact primary and secondary mechanisms of injury have not been elucidated and appearance of cellular injury can vary based on many factors, such as blast overpressure magnitude and duration. Many methodologies to study blast neurotrauma have been employed, ranging from open-field explosives to experimental shock tubes for producing free-field blast waves. While there are benefits to the various methods, certain specifications need to be accounted for in order to properly examine BINT. Primary cell injury mechanisms, occurring as a direct result of the blast wave, have been identified in several studies and include cerebral vascular damage, blood-brain barrier disruption, axonal injury, and cytoskeletal damage. Secondary cell injury mechanisms, triggered subsequent to the initial insult, result in the activation of several molecular cascades and can include, but are not limited to, neuroinflammation and oxidative stress. The collective result of these secondary injuries can lead to functional deficits. Behavioral measures examining motor function, anxiety traits, and cognition/memory problems have been utilized to determine the level of injury severity. While cellular injury mechanisms have been identified following blast exposure, the various experimental models present both concurrent and conflicting results. Furthermore, the temporal response and progression of pathology after blast exposure have yet to be detailed and remain unclear due to limited resemblance of methodologies. This chapter summarizes the current state of blast neuropathology and emphasizes the need for a standardized preclinical model of blast neurotrauma.

  7. System dynamic instabilities induced by sliding contact: A numerical analysis with experimental validation

    NASA Astrophysics Data System (ADS)

    Brunetti, J.; Massi, F.; Saulot, A.; Renouf, M.; D`Ambrogio, W.

    2015-06-01

    Mechanical systems present several contact surfaces between deformable bodies. The contact interface can be either static (joints) or in sliding (active interfaces). The sliding interfaces can have several roles and according to their application they can be developed either for maximizing the friction coefficient and the energy dissipation (e.g. brakes) or rather to allow the relative displacement at joints with a maximum efficiency. In both cases the coupling between system and local contact dynamics can bring to system dynamics instabilities (e.g. brake squeal or squeaking of hip prostheses). This results in unstable vibrations of the system, induced by the oscillation of the contact forces. In the literature, a large number of works deal with such kind of instabilities and are mainly focused on applied problems such as brake squeal noise. This paper shows a more general numerical analysis of a simple system constituted by two bodies in sliding contact: a rigid cylinder rotating inside a deformable one. The parametrical Complex Eigenvalue Analysis and the transient numerical simulations show how the friction forces can give rise to in-plane dynamic instabilities due to the interaction between two system modes, even for such a simple system characterized by one deformable body. Results from transient simulations highlight the key role of realistic values of the material damping to have convergence of the model and, consequently, reliable physical results. To this aim an experimental estimation of the material damping has been carried out. Moreover, the simplicity of the system allows for a deeper analysis of the contact instability and a balance of the energy flux among friction, system vibrations and damping. The numerical results have been validated by comparison with experimental ones, obtained by a specific test bench developed to reproduce and analyze the contact friction instabilities.

  8. Cellular Mechanisms and Behavioral Outcomes in Blast-Induced Neurotrauma: Comparing Experimental Setups.

    PubMed

    Bailey, Zachary S; Hubbard, W Brad; VandeVord, Pamela J

    2016-01-01

    Blast-induced neurotrauma (BINT) has increased in incidence over the past decades and can result in cognitive issues that have debilitating consequences. The exact primary and secondary mechanisms of injury have not been elucidated and appearance of cellular injury can vary based on many factors, such as blast overpressure magnitude and duration. Many methodologies to study blast neurotrauma have been employed, ranging from open-field explosives to experimental shock tubes for producing free-field blast waves. While there are benefits to the various methods, certain specifications need to be accounted for in order to properly examine BINT. Primary cell injury mechanisms, occurring as a direct result of the blast wave, have been identified in several studies and include cerebral vascular damage, blood-brain barrier disruption, axonal injury, and cytoskeletal damage. Secondary cell injury mechanisms, triggered subsequent to the initial insult, result in the activation of several molecular cascades and can include, but are not limited to, neuroinflammation and oxidative stress. The collective result of these secondary injuries can lead to functional deficits. Behavioral measures examining motor function, anxiety traits, and cognition/memory problems have been utilized to determine the level of injury severity. While cellular injury mechanisms have been identified following blast exposure, the various experimental models present both concurrent and conflicting results. Furthermore, the temporal response and progression of pathology after blast exposure have yet to be detailed and remain unclear due to limited resemblance of methodologies. This chapter summarizes the current state of blast neuropathology and emphasizes the need for a standardized preclinical model of blast neurotrauma. PMID:27604716

  9. Human mesenchymal stem cells attenuate experimental bronchopulmonary dysplasia induced by perinatal inflammation and hyperoxia

    PubMed Central

    Chou, Hsiu-Chu; Li, Yuan-Tsung; Chen, Chung-Ming

    2016-01-01

    Background: Systemic maternal inflammation and neonatal hyperoxia arrest alveolarization in neonates. The aims were to test whether human mesenchymal stem cells (MSCs) reduce lung inflammation and improve lung development in perinatal inflammation- and hyperoxia-induced experimental bronchopulmonary dysplasia. Methods: Pregnant Sprague-Dawley rats were intraperitoneally injected with lipopolysaccharide (LPS, 0.5 mg/kg/day) on Gestational Days 20 and 21. Human MSCs (3×105 and 1×106 cells) in 0.03 ml normal saline (NS) were administered intratracheally on Postnatal Day 5. Pups were reared in room air (RA) or an oxygen-enriched atmosphere (O2) from Postnatal Days 1 to 14, and six study groups were obtained: LPS+RA+NS, LPS+RA+MSC (3×105 cells), LPS+RA+MSC (1×106 cells), LPS+O2+NS, LPS+O2+MSC (3×105 cells), and LPS+O2+MSC (1×106 cells). The lungs were excised for cytokine, vascular endothelial growth factor (VEGF) and connective tissue growth factor (CTGF) expression, and histological analyses on Postnatal Day 14. Results: Body weight was significantly lower in rats reared in hyperoxia than in those reared in RA. The LPS+O2+NS group exhibited a significantly higher mean linear intercept (MLI) and collagen density and a significantly lower vascular density than the LPS+RA+NS group did. Administering MSC to hyperoxia-exposed rats improved MLI and vascular density and reduced tumor necrosis factor-α and interleukin-6 levels and collagen density to normoxic levels. This improvement in lung development and fibrosis was accompanied by an increase and decrease in lung VEGF and CTGF expression, respectively. Conclusion: Human MSCs attenuated perinatal inflammation- and hyperoxia-induced defective alveolarization and angiogenesis and reduced lung fibrosis, likely through increased VEGF and decreased CTGF expression. PMID:27158330

  10. Gastroprotective Efficacy and Safety Evaluation of Scoparone Derivatives on Experimentally Induced Gastric Lesions in Rodents

    PubMed Central

    Son, Dong Ju; Lee, Gyung Rak; Oh, Sungil; Lee, Sung Eun; Choi, Won Sik

    2015-01-01

    This study investigated the gastroprotective efficacy of synthesized scoparone derivatives on experimentally induced gastritis and their toxicological safety. Six scoparone derivatives were synthesized and screened for gastroprotective activities against HCl/ethanol- and indomethacin-induced gastric ulcers in rats. Among these compounds, 5,6,7-trimethoxycoumarin and 6,7,8-trimethoxycoumarin were found to have gastroprotective activity greater than the standard drug rebamipide; 6-methoxy-7,8-methylenedioxycoumarin, 6-methoxy-7,8-(1-methoxy)-methylenedioxycoumarin, 6,7-methylenedioxycoumarin, and 6,7-(1-methoxy)-methylenedioxycoumarin were found to be equipotent or less potent that of rebamipide. Pharmacological studies suggest that the presence of a methoxy group at position C-5 or C-8 of the scoparone’s phenyl ring significantly improves gastroprotective activity, whereas the presence of a dioxolane ring at C-6, C-7, or C-8 was found to have decreased activity. In order to assess toxicological safety, two of the potent gastroprotective scoparone derivatives—5,6,7-trimethoxycoumarin and 6,7,8-trimethoxycoumarin—were examined for their acute toxicity in mice as well as their effect on cytochrome P450 (CYP) enzyme activity. These two compounds showed low acute oral toxicity in adult male and female mice, and caused minimal changes to CYP3A4 and CYP2C9 enzyme activity. These results indicate that compared to other scoparone derivatives, 5,6,7-trimethoxycoumarin and 6,7,8-trimethoxycoumarin can improve gastroprotective effects, and they have low toxicity and minimal effects on drug-metabolizing enzymes. PMID:25781220

  11. Effect of a lipid-rich emollient containing ceramide 3 in experimentally induced skin barrier dysfunction.

    PubMed

    Kucharekova, M; Schalkwijk, J; Van De Kerkhof, P C M; Van De Valk, P G M

    2002-06-01

    In the present study we compared the effect of a ceramide 3-containing emollient (Locobase(R) Repair) with a control emollient (vaselinum album/cremor lanette ana) and untreated damaged skin using clinical, bioengineering and immunohistochemical methods in two different models of experimentally induced skin barrier dysfunction. In model A (n = 13) skin barrier dysfunction was inflicted at three investigation sites by tape stripping. In model B (n = 13) the volunteers were patch tested at three investigation sites with sodium dodecyl sulphate (0.2%) for 4 h a day for 4 consecutive days. The investigation sites were treated once a day with the above-mentioned agents. Irritant reaction was assessed daily by erythema scoring and measurements of transepidermal water loss (TEWL). After 5D, punch biopsies were taken from all sites. Immunohistochemical assessment was carried out with respect to epidermal proliferation, epidermal differentiation and Langerhans cells. Tape stripping resulted in an erythematous reaction and an increase of TEWL associated with up-regulation of cycling cells, involucrin and expression of cytokeratin 16. At day 4, ceramide 3-containing emollient significantly decreased (p < 0.03) the erythema score, TEWL and cycling cells in comparison with the untreated site. Repetitive exposure to SDS induced a variable degree of erythema, gradual increase of TEWL, an increase of cycling cells, and up-regulation of involucrin, E-FABP and SKALP. The treatment with the control emollient significantly prevented erythema, increase of TEWL and cycling cells at day 4 compared to the untreated site. In summary, the present study demonstrated that both tested emollients improve skin barrier in different conditions compared to the untreated skin. There is some indication that formulations containing skin-related lipids might be of benefit in barrier disruption following tape stripping. Different models and clinical trials are needed to establish the usefulness in

  12. The tick saliva immunosuppressor, Salp15, contributes to Th17-induced pathology during Experimental Autoimmune Encephalomyelitis

    PubMed Central

    Juncadella, Ignacio J.; Bates, Tonya C.; Suleiman, Reem; Monteagudo-Mera, Andrea; Olson, Chris M.; Navasa, Nicolás; Olivera, Elias R.; Osborne, Barbara A.; Anguita, Juan

    2010-01-01

    Summary Salp15 is a tick saliva protein that inhibits CD4+ T cell differentiation through its interaction with CD4. The protein inhibits early signaling events during T cell activation and IL-2 production. Because murine experimental autoimmune encephalomyelitis development is mediated by central nervous system-infiltrating CD4+ T cells that are specific for myelin-associated proteins, we sought to determine whether the treatment of mice with Salp15 during EAE induction would prevent the generation of proinflammatory T cell responses and the development of the disease. Surprisingly, Salp15-treated mice developed more severe EAE than control animals. The treatment of EAE-induced mice with the tick saliva protein did not result in increased infiltration of T cells to the central nervous system, indicating that Salp15 had not affected the permeability of the blood-brain barrier. Salp15 treatment did not affect the development of antibody responses against the eliciting peptide or the presence of IFNγ in the sera. The treatment with Salp15 resulted, however, in the increased differentiation of Th17 cells in vivo, as evidenced by higher IL-17 production from PLP139-151-specific CD4+ T cells isolated from the central nervous system and the periphery. In vitro, Salp15 was able to induce the differentiation of Th17 cells in the presence of IL-6 and the absence of TGFβ These results suggest that a conductive milieu for the differentiation of Th17 cells can be achieved by restriction of the production of IL-2 during T cell differentiation, a role that may be performed by TGFβ and other immunosuppressive agents. PMID:20920474

  13. Methylglyoxal-induced neuroinflammatory response in in vitro astrocytic cultures and hippocampus of experimental animals.

    PubMed

    Chu, John M T; Lee, Dicky K M; Wong, Daniella P K; Wong, Gordon T C; Yue, Kevin K M

    2016-10-01

    Diabetes mellitus is characterized by chronic hyperglycemia and its diverse complications. Hyperglycemia is associated with inflammatory responses in different organs and diabetic patients have a higher risk of developing neurodegenerative disorders. Methylglyoxal is a reactive advanced glycation end product precursor that accumulates in diabetic patients. It induces various stress responses in the central nervous system and causes neuronal dysfunction. Astrocytes are actively involved in maintaining neuronal homeostasis and possibly play a role in protecting the brain against neurodegeneration. However it is not clear whether methylglyoxal exerts any adverse effects towards these astrocytes. In the present study we investigated the effects of methylglyoxal in astrocytic cultures and hippocampi of experimental animals. The cells from the astrocytic line DITNC1 were treated with methylglyoxal for 1 to 24 h. For the in vivo model, 3 months old C57BL/6 mice were treated with methylglyoxal solution for 6 weeks by intraperitoneal injection. Following the treatment, both astrocytes and hippocampi were harvested for MTT assay, Western blot and real time PCR analyses. We found that methylglyoxal induced astrogliosis in DITNC1 astrocytic cultures and C57BL/6 mice. Further, activation of the pro-inflammatory JNK signaling pathway and its downstream effectors c-Jun were observed. Furthermore, increased gene expression of pro-inflammatory cytokines and astrocytic markers were observed from real time PCR analyses. In addition, inhibition of JNK activities resulted in down-regulation of TNF-α gene expression in methylglyoxal treated astrocytes. Our results suggest that methylglyoxal may contribute to the progression of diabetes related neurodegeneration through JNK pathway activation in astrocytes and the subsequent neuroinflammatory responses in the central nervous system. PMID:27250968

  14. Tracking anti-fibrotic pathways of nilotinib and imatinib in experimentally induced liver fibrosis: an insight.

    PubMed

    Shiha, Gamal E; Abu-Elsaad, Nashwa M; Zalata, Khaled R; Ibrahim, Tarek M

    2014-10-01

    The tyrosine kinase inhibitors imatinib and nilotinib have been suggested to have promising antifibrotic activity in experimental models of liver fibrosis. The aim of the present study was to investigate new pathways underlying this beneficial effect. Hepatic injury was induced in male Wistar rats by intraperitoneal injection of CCl4 for 12 weeks. During the last 8 weeks of treatment, rats were also injected daily intraperitoneally with 20 mg/kg imatinib or 20, 10 or 5 mg/kg nilotinib. At the end of treatment, effects on fibrosis were assessed by measuring serum fibrotic markers and profibrogenic cytokines, as well as by histopathological examination. Possible anti-inflammatory effects were estimated by measuring levels of inflammatory cytokines in liver tissue. Liver expression of α-smooth muscle actin, transforming growth factor (TGF)-β1 antibodies and platelet-derived growth factor receptor β (PDGFRβ) was evaluated by immunohistochemical staining techniques. Nilotinib (5 and 10 mg/kg) significantly (P < 0.05) decreased all serum fibrotic markers measured, but 20 mg/kg of either nilotinib or imatinib had limited effects. At all doses tested, nilotinib significantly (P < 0.05) decreased the CCl4 -induced increases in tissue inflammatory cytokines. Furthermore, 5 and 10 mg/kg nilotinib significantly decreased TGF-β1 levels and tissue expression of its antibody, as well expression of PDGFRβ. In conclusion, low doses (5 and 10 but not 20 mg/kg) of nilotinib, rather than imatinib, can control hepatic fibrosis by regulating levels of proinflammatory cytokines, primarily interleukin (IL)-1 and IL-6. Nilotinib also controls the signalling pathways of profibrogenic cytokines by lowering TGF-β1 levels and decreasing expression of PDGFRβ.

  15. Effect of pioglitazone, quercetin and hydroxy citric acid on extracellular matrix components in experimentally induced non-alcoholic steatohepatitis

    PubMed Central

    Mohan, Surapaneni Krishna; Veeraraghavan, Vishnu Priya; Jainu, Mallika

    2015-01-01

    Objective(s): Non-alcoholic steatohepatitis (NASH), is an important component of Non-alcoholic fatty liver disease (NAFLD) spectrum, which progresses to the end stage liver disease, if not diagnosed and treated properly. The disproportionate production of pro- and anti-inflammatory adipokines secreted from fat contributes to the pathogenesis of NASH. In this study, the comparative effect of pioglitazone, quercetin and hydroxy citric acid on extracellular matrix (ECM) component levels were studied in experimentally induced NASH. Materials and Methods: The experimental protocol consists of using 48 male Wister rats, which were divided into 8 groups. The levels of hyaluronic acid, leptin and adiponectin were monitored in experimental NASH. Results: The experimental NASH rats treated with pioglitazone showed significant decrease in the levels of hyaluronic acid and significant increase in adiponectin levels when compared to experimentally induced NASH group, but did not show any effect on the levels of leptin. Contrary to these two drugs, viz. pioglitazone and hydroxy citric acid, the group treated with quercetin showed significant decrease in the levels of hyaluronic acid and leptin and significant decrease in adiponectin levels compared with that of experimentally induced NASH NASH group, offering maximum protection against NASH. Conclusion: Considering our findings, it could be concluded that quercetin may offer maximum protection against NASH by significantly increasing the levels of adiponectin, when compared to pioglitazone and hydroxy citric acid. PMID:26557974

  16. Ultrasound stimulation attenuates resorption of tooth root induced by experimental force application.

    PubMed

    Inubushi, Toshihiro; Tanaka, Eiji; Rego, Emanuel B; Ohtani, Junji; Kawazoe, Aki; Tanne, Kazuo; Miyauchi, Mutsumi; Takata, Takashi

    2013-04-01

    Root resorption is an adverse outcome of orthodontic tooth movement. However, there have been no available approaches for the protection and repair of root resorption. The aim of this study was to evaluate the effects of low-intensity pulsed ultrasound (LIPUS) on root resorption during experimental tooth movement and the effects of LIPUS in the RANKL/OPG mechanism in osteoblasts and cementoblasts in vitro. Twenty four Wistar strain male rats of 12-week-old were used in this study. The upper first molars were subjected to experimental movement in the mesial direction for 1-3weeks. Through the experimental periods, the right upper first maxillary molar was exposed to LIPUS (LIPUS group) every day for 1, 2 or 3weeks. The nature of root resorption was observed and then quantified by histomorphometric analysis. In the 2weeks period, significantly greater amount of tooth movement was observed in the LIPUS group (p<0.05). In addition, LIPUS group showed less root resorption lacunae and lower number of odontoclasts. In the period of 3weeks, LIPUS group presented significantly shorter length of root resorption lacunae and smaller amount of root resorption area (p<0.01). The number of odontoclasts and osteoclasts was also significantly lower in the LIPUS group (p<0.01 and p<0.05, respectively). However, no significant differences could be found regarding the amount of tooth movement. It is shown that LIPUS exposure significantly reduced the degree of root resorption during tooth movement without interrupting tooth movement. In vitro experiments showed that MC3T3-1 constitutively expressed higher levels of RANKL and RANTES mRNA comparing to OCCM-30. However, OPG mRNA expression was much higher in OCCM-30. LIPUS stimulation significantly increased the mRNA expression of RANKL in MC3T3-E1 at 4 (p<0.01) and 12h (p<0.05), although OPG mRNA expression was not affected by LIPUS. In contrast, the expression of RANKL and OPG mRNAs were both significantly increased by LIPUS in OCCM-30

  17. [Experimental detection of integration of mTDNA in the nuclear genome induced by ionizing radiation].

    PubMed

    Abdullaev, S A; Fomenko, L A; Kuznetsova, E A; Gaziev, A I

    2013-01-01

    Transfer of mtDNA in the nuclear genome is usually regarded as a continued and dynamic process of forming numt-pseudogenes or numt-insertions. They can be regarded not only as a neutral polymorphism, but may be involved in oncogenesis, aging and genetic diseases. Experimental identification of numt-insertions arising de novo is limited due to the presence of numerous homology mtDNA constitutively existing in the nuclear genomes of eukaryotes. It is known that the chick nuclear DNA (nDNA) constitutively contains 12 numt-pseudogenes. We attempted to experimentally detect the formation of numt-insertions de novo in the nDNA of chick embryos (Gallus gallus) from the eggs exposed to X-rays. Free mtDNAs were removed from preparations of nDNA of liver embryos through double gel electrophoresis. Numt-inserts in nDNA of control and survival embryos (from irradiated eggs) were revealed by PCR using 11 pairs of primers flanking the region of mtDNA of about 300-400 bp. PCR analysis with nDNA of control group showed no presence of homology mtDNA amplified with selected primers. PCR assays of nDNA of eight embryos from irradiated eggs showed that nDNA of two embryos contained new sites of mtDNA. PCR amplification of 3 loci of mtDNA is stably detected in nDNA from one embryo and 4 loci of mtDNA in nDNA from another embryo. Sequencing of PCR amplicons synthesized on templates of these nDNA showed that their sequences are identical to mtDNA and accurately cover the sites of several genes and the site of mtDNA D-loop. Thus, the experimental results indicate that ionizing radiation can induce integration of mtDNA fragments in the nuclear genome, apparently, through the mechanism of nonhomologous end-joining repair of double-strand breaks of nDNA.

  18. Cardiac isoenzymes in healthy Holstein calves and calves with experimentally induced endotoxemia

    PubMed Central

    Peek, Simon F.; Apple, Fred S.; Murakami, Mary Ann; Crump, Peter M.; Semrad, Susan D.

    2008-01-01

    This paper describes a controlled study designed to establish normal values for cardiac troponins I and T (cTnI and cTnT) and CK-MB mass in healthy newborn Holstein calves, and to compare values for cTnI, cTnT, CK-MB and total creatine kinase (CK) with age-matched calves experiencing experimentally induced endotoxemia. Nineteen healthy Holstein bull calves, 48 to 72 h of age were used. Baseline cTnI, cTnT, CK-MB and total CK measurements were obtained from control (n = 9) and experimental (n = 10) calves. Controls then received physiological saline and experimental calves received endotoxin (O55:B5 Escherichia coli LPS) intravenously after which cardiac biomarkers and total CK were measured at 3 h, 6 h, 12 h, and 24 h post-initiation of infusion. Measured values were analyzed and compared using analysis of variance (ANOVA) by repeated measure design, with statistical significance set at P < 0.05. The cardiac biomarker cTnT was not detected in any calf at any time point, and CK-MB was only detected in 5 of 95 samples. The cTnI was significantly increased compared to baseline and controls, 3 h post lipopolysaccharide (LPS) infusion. Total CK was significantly increased in LPS administered calves at 18 and 24 h post infusion. The mean, standard deviation, and range for cTnI in healthy controls were 0.023 ng/mL (s = 0.01), and 0.01 to 0.05 ng/mL, respectively. In conclusion, LPS administration was associated with rapid and significant increases in cTnI but CK-MB and cTnT were not detected in the plasma of healthy calves. Total CK values increased significantly following LPS administration. Biochemical evidence of myocardial injury occurs within 3 h following LPS administration to neonatal Holstein calves. PMID:18783025

  19. Experimental study on impact-induced seismic wave propagating through quartz sand simulating asteroid regolith

    NASA Astrophysics Data System (ADS)

    Matsue, Kazuma; Arakawa, Masahiko; Yasui, Minami; Matsumoto, Rie; Tsujido, Sayaka; Takano, Shota; Hasegawa, Sunao

    2015-08-01

    Introduction: Recent spacecraft surveys clarified that asteroid surfaces were covered with regolith made of boulders and pebbles such as that found on the asteroid Itokawa. It was also found that surface morphologies of asteroids formed on the regolith layer were modified. For example, the high-resolution images of the asteroid Eros revealed the evidence of the downslope movement of the regolith layer, then it could cause the degradation and the erasure of small impact crater. One possible process to explain these observations is the regolith layer collapse caused by seismic vibration after projectile impacts. The impact-induced seismic wave might be an important physical process affecting the morphology change of regolith layer on asteroid surfaces. Therefore, it is significant for us to know the relationship between the impact energy and the impact-induced seismic wave. So in this study, we carried out impact cratering experiments in order to observe the seismic wave propagating through the target far from the impact crater.Experimental method: Impact cratering experiments were conducted by using a single stage vertical gas gun set at Kobe Univ and a two-stage vertical gas gun set at ISAS. We used quartz sands with the particle diameter of 500μm, and the bulk density of 1.48g/cm3. The projectile was a ball made of polycarbonate with the diameter of 4.75mm and aluminum, titan, zirconia, stainless steel, cupper, tungsten carbide projectile with the diameter of 2mm. These projectiles were launched at the impact velocity from 0.2 to 7km/s. The target was set in a vacuum chamber evacuated below 10 Pa. We measured the seismic wave by using a piezoelectric uniaxial accelerometer.Result: The impact-induced seismic wave was measured to show a large single peak and found to attenuate with the propagation distance. The maximum acceleration of the seismic wave was recognized to have a good relationship with the normalized distance x/R, where x is the propagation distance

  20. The pathogenesis of experimentally induced amebic liver abscess in the gerbil (Meriones unguiculatus).

    PubMed Central

    Chadee, K.; Meerovitch, E.

    1984-01-01

    Sequential development and pathology of experimentally induced amebic liver abscess in the gerbil (Meriones unguiculatus) were studied from 1 to 60 days after inoculation. Early lesions were characterized by an acute inflammatory response, which became granulomatous at 5 days. Early granulomas were discrete, with well-defined fibrohistiocytic walls. Trophozoite dissemination as a result of fibrolysis of granuloma wall was confined to the liver parenchyma. The granulomatous cellular infiltrate (less than 20 days) was characterized by granulocytes and histiocytes; older granulomas (greater than 30 days) were composed of lymphocytic infiltrate, plasma cells, and a few granulocytes, and were characterized by the absence of epithelioid histiocytes. The degree of pathologic change adjacent to liver granulomas followed the sequential development of the amebic liver abscess. Severe changes observed were portal canal lymphocytic infiltration, the presence of foreign body giant cells, periportal fibrosis, proliferation of bile duct epithelium, and hepatocyte anisonucleosis and ballooning degeneration. The pathogenesis of the infection and the usefulness of the gerbil model for the study of human amebiasis are discussed. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 PMID:6385727

  1. Induced Cannibalism in Experimental Populations of the Forensic Indicator Chrysomya putoria Wiedemann (Diptera: Calliphoridae).

    PubMed

    Botteon, V W; Fernandes, F S; Godoy, W A C

    2016-04-01

    We analyzed the behavior of third-instars of Chrysomya putoria as potential cannibals in experimental populations. Cannibalism rates were evaluated in three settings observed for 3, 6, 9, and 24 h, placing injured and uninjured larvae of C. putoria together. Our data heavily support that C. putoria larvae behave as cannibals when induced by a wound in another larva, and also after starving for 24 h. The probability of cannibalism increased as a function of time, both in no-choice and in choice experiments evidencing that time is a determining factor for cannibalism induction in C. putoria. However, the treatment combining injured with uninjured larvae showed the highest probability of cannibalism. These results suggest that C. putoria larvae may cannibalize under scarcity of food over long time or the presence of injured larvae. This study is useful to understand the behavior of C. putoria feeding on ephemeral substrates such as carrion or corpses and brings relevant and significant contribution to population ecology of blowflies and also forensic entomology. PMID:26698866

  2. Quantitative evaluation of an experimental inflammation induced with Freund's complete adjuvant in dogs.

    PubMed

    Botrel, M A; Haak, T; Legrand, C; Concordet, D; Chevalier, R; Toutain, P L

    1994-10-01

    A chronic inflammation model in dogs was induced by intraarticular injection of Freund's Complete Adjuvant in the stifle. After a primary, acute response during the first 24 hr, a secondary subacute response was observed after a delay of approximately 3 weeks and persisted for several weeks. To evaluate the time course of the inflammatory process quantitatively, we tested more than 100 different parameters. Finally, only four parameters were selected based on practicability and metrological properties, namely, the body temperature, difference in skin temperature, difference in stifle diameter and vertical force exerted by arthritic hind limb measured using a force plate. The main results of the experimentation were the demonstration that these four parameters were sufficiently repeatable, reproducible, and appropriate to be used for quantitative evaluation of the inflammatory process, and that training of both animals and investigators was required. Finally, it was illustrated that an adjuvant periarthritis in dogs can be used to carry out a pharmacokinetic/pharmacodynamic modelling of an antiinflammatory drug. PMID:7865864

  3. Illusions and Delusions: Relating Experimentally-Induced False Memories to Anomalous Experiences and Ideas

    PubMed Central

    Corlett, Philip R.; Simons, Jon S.; Pigott, Jennifer S.; Gardner, Jennifer M.; Murray, Graham K.; Krystal, John H.; Fletcher, Paul C.

    2009-01-01

    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 that has not previously been presented is falsely remembered. 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. PMID:19956402

  4. Two randomized controlled trials of zinc gluconate lozenge therapy of experimentally induced rhinovirus colds.

    PubMed Central

    Farr, B M; Conner, E M; Betts, R F; Oleske, J; Minnefor, A; Gwaltney, J M

    1987-01-01

    The therapeutic efficacy of zinc gluconate lozenge therapy in experimentally induced rhinovirus infection was assessed in two randomized controlled trials in susceptible adult volunteers. In trial 1, lozenges containing either zinc gluconate (23 mg of elemental zinc) or placebo were given 36 h after nasal inoculation of rhinovirus type 39 and administered eight times per day for 5 days. All of the volunteers had early cold symptoms at the time that treatment was begun. In trial 2, the same lozenge regimen was used, beginning 2 h after nasal inoculation with rhinovirus type 13, and continued for 7 days. Zinc therapy did not reduce the severity or duration of cold symptoms or the frequency or duration of viral shedding in either trial. Viral titers were measured in trial 2 and were shown to be unaffected by zinc therapy. Nasal mucus weights and the numbers of paper tissues used were slightly higher in zinc recipients. A statistically significant increase in levels of zinc in serum was documented in zinc recipients after 5 days of therapy. These data suggest that zinc gluconate lozenge therapy is not therapeutically useful in the treatment of rhinovirus colds. PMID:2820298

  5. Activity of cathepsins in rat's spleen due to experimentally induced pancreatitis.

    PubMed

    Maciejewski, R; Burdan, F; Madej, B; Kiś, G; Szkodziak, P; Burski, K

    The aim of this study was to establish and quantify the changes of the level of cathepsin B, D and L in the spleen during experimental pancreatitis. The experiment was carried out in 115 male Wistar rats, randomly divided into three groups: intact (n = 15), injected with 0.9% NaCl solution into the common bile pancreatic duct (n = 50) and injected with 5% sodium taurocholate into this duct to induce acute pancreatitis (n = 50). After 2, 6, 12, 24 and 48 hours rats were anaesthetised, and blood was taken for amylase determination from the heart, and the spleen was removed. Alpha-amylase level in the blood serum samples was measured by enzymatic method. Cathepsin activity was established by spectrophotometric methods using substrates which form coloured complexes when they react with these proteases. The specific free fraction activity of cathepsin B, D and L in the spleen changed during the course of experiment, but there was no correlation between their activity and the intensity of pancreatitis established by serum amylase level.

  6. Blockade of Extracellular ATP Effect by Oxidized ATP Effectively Mitigated Induced Mouse Experimental Autoimmune Uveitis (EAU)

    PubMed Central

    Zhao, Ronglan; Liang, Dongchun; Sun, Deming

    2016-01-01

    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. PMID:27196432

  7. Collision induced dissociation study of azobenzene and its derivatives: computational and experimental results

    NASA Astrophysics Data System (ADS)

    Rezaee, Mohammadreza; Compton, Robert

    2015-03-01

    Experimental and computational investigation have been performed in order to study the bond dissociation energy of azobenzene and its derivatives using collision induced dissociation method as well as other energy and structural characteristics. The results have been verified by comparing with results obtained from computational quantum chemistry. We used different density functional methods as well as the Möller-Plesset perturbation theory and the coupled cluster methods to explore geometric, electronic and the spectral properties of the sample molecules. Geometries were calculated and optimized using the 6-311 + + G(2d,2p) basis set and the B3LYP level of theory and these optimized structures have been subjected to the frequency calculations to obtain thermochemical properties by means of different density functional, Möller-Plesset, and coupled cluster theories to obtain a high accuracy estimation of the bond dissociation energy value. The results from experiments and the results obtained from computational thermochemistry are in close agreement. Physics and Astronomy Department

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

    SciTech Connect

    Thiyagarajan, Magesh; Scharer, John

    2008-07-01

    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 {mu}m 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{sub 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.

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

    NASA Astrophysics Data System (ADS)

    Thiyagarajan, Magesh; Scharer, John

    2008-07-01

    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 N2C-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.

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

    NASA Technical Reports Server (NTRS)

    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.

  11. Experimental characterization of fire-induced response of rigid polyurethane foam

    SciTech Connect

    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.

  12. Experimental evidence for drought induced alternative stable states of soil moisture

    NASA Astrophysics Data System (ADS)

    Robinson, David. A.; Jones, Scott B.; Lebron, Inma; Reinsch, Sabine; Domínguez, María T.; Smith, Andrew R.; Jones, Davey L.; Marshall, Miles R.; Emmett, Bridget A.

    2016-01-01

    Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ~10%. However, intense summer drought, superimposed on the experiment, that began in 2003 and peaked in 2005 caused an unexpected erosion of resilience and a shift to an ASS; both for the experimental drought manipulation and control plots, impairing the soil from rewetting in winter. Measurements outside plots, with vegetation removal, showed no evidence of moisture shifts. Further independent evidence supports our findings from historical soil moisture monitoring at a long-term upland hydrological observatory. The results herald the need for a new paradigm regarding our understanding of soil structure, hydraulics and climate interaction.

  13. Experimental evidence for drought induced alternative stable states of soil moisture

    PubMed Central

    Robinson, David. A.; Jones, Scott B.; Lebron, Inma; Reinsch, Sabine; Domínguez, María T.; Smith, Andrew R.; Jones, Davey L.; Marshall, Miles R.; Emmett, Bridget A.

    2016-01-01

    Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ~10%. However, intense summer drought, superimposed on the experiment, that began in 2003 and peaked in 2005 caused an unexpected erosion of resilience and a shift to an ASS; both for the experimental drought manipulation and control plots, impairing the soil from rewetting in winter. Measurements outside plots, with vegetation removal, showed no evidence of moisture shifts. Further independent evidence supports our findings from historical soil moisture monitoring at a long-term upland hydrological observatory. The results herald the need for a new paradigm regarding our understanding of soil structure, hydraulics and climate interaction. PMID:26804897

  14. Experimental evidence for drought induced alternative stable states of soil moisture.

    PubMed

    Robinson, David A; Jones, Scott B; Lebron, Inma; Reinsch, Sabine; Domínguez, María T; Smith, Andrew R; Jones, Davey L; Marshall, Miles R; Emmett, Bridget A

    2016-01-01

    Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ~10%. However, intense summer drought, superimposed on the experiment, that began in 2003 and peaked in 2005 caused an unexpected erosion of resilience and a shift to an ASS; both for the experimental drought manipulation and control plots, impairing the soil from rewetting in winter. Measurements outside plots, with vegetation removal, showed no evidence of moisture shifts. Further independent evidence supports our findings from historical soil moisture monitoring at a long-term upland hydrological observatory. The results herald the need for a new paradigm regarding our understanding of soil structure, hydraulics and climate interaction. PMID:26804897

  15. Gamma interferon is a major mediator of antiviral defense in experimental measles virus-induced encephalitis.

    PubMed Central

    Finke, D; Brinckmann, U G; ter Meulen, V; Liebert, U G

    1995-01-01

    Measles virus infection of the central nervous system in the murine model of experimental measles virus-induced encephalitis is successfully controlled by virus-specific T-helper lymphocytes. T cells from BALB/c mice that are resistant to measles virus encephalitis proliferate well against measles virus in vitro, and bulk cultures recognize viral nucleocapsid and hemagglutinin as well as fusion proteins. The measles virus-specific T cells secrete large amounts of interleukin 2 (IL-2), gamma interferon (IFN-gamma), and tumor necrosis factor alpha (TNF-alpha) but no IL-4, IL-6, or IL-10, and hence the cytokine pattern is consistent with that of subtype 1 T-helper lymphocytes. In contrast, cells obtained from measles virus-infected susceptible C3H mice recognize measles virus proteins only weakly and secrete little IFN-gamma and TNF-alpha. Treatment of infected mice with anti-TNF-alpha antibodies has no effect on survival or virus clearance from the brain. Upon neutralization of IFN-gamma in vivo, the phenotype of measles virus-specific T-helper cells isolatable from BALB/c mice is reversed from subtype 1 to subtype 2-like. Anti-IFN-gamma antibody-treated BALB/c mice are susceptible to measles virus encephalitis, and viral clearance from the central nervous system is impaired. These results indicate that IFN-gamma plays a significant role in the control of measles virus infection of the central nervous system. PMID:7636992

  16. Circulating and localized immune complexes in experimental mycoplasma-induced arthritis-associated ocular inflammation.

    PubMed Central

    Thirkill, C E; Tyler, N K; Roth, A M

    1992-01-01

    Ocular deposits of immune complexes are believed to contribute to the anterior segment inflammations observed in association with the human arthritides. Arthritis-related ocular inflammations may be reproduced in animals by infection with certain species of mycoplasma. To evaluate the role of immune complexes in the production of ocular lesions, we studied their involvement in the rodent model of experimental arthritis-associated ocular inflammation induced by Mycoplasma arthritidis. Sprague-Dawley rats were infected with viable concentrates of M. arthritidis and monitored for the production of related circulating and intraocular immune complexes. Circulating immune complexes were monitored by antigen capture systems, and localized intraocular complexes were identified by indirect immunohistochemistry. Polyacrylamide gel immunoblot analysis of captured complexes confirmed the antigen(s) involved as proteins derived from M. arthritidis. Indirect immunofluorescence revealed localized complexes containing mycoplasma antigens within the ciliary-iris vasculature. Concentrations of the generated complexes diminished rapidly over a 30-day period. While complex deposits within ocular tissues could represent a contributing cause to the localized anterior segment inflammation reported in this rodent model, secondary challenge with viable M. arthritidis, which reproduced high concentrations of intraocular and circulating immune complexes, failed to elicit any ocular response. Images PMID:1730469

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

    NASA Astrophysics Data System (ADS)

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

    2010-10-01

    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.

  18. Modeling and simulation of organophosphate-induced neurotoxicity: Prediction and validation by experimental studies.

    PubMed

    Greget, Renaud; Dadak, Selma; Barbier, Laure; Lauga, Fabien; Linossier-Pierre, Sandra; Pernot, Fabien; Legendre, Arnaud; Ambert, Nicolas; Bouteiller, Jean-Marie; Dorandeu, Frédéric; Bischoff, Serge; Baudry, Michel; Fagni, Laurent; Moussaoui, Saliha

    2016-05-01

    Exposure to organophosphorus (OP) compounds, either pesticides or chemical warfare agents, represents a major health problem. As potent irreversible inhibitors of cholinesterase, OP may induce seizures, as in status epilepticus, and occasionally brain lesions. Although these compounds are extremely toxic agents, the search for novel antidotes remains extremely limited. In silico modeling constitutes a useful tool to identify pharmacological targets and to develop efficient therapeutic strategies. In the present work, we developed a new in silico simulator in order to predict the neurotoxicity of irreversible inhibitors of acetyl- and/or butyrylcholinesterase (ChE) as well as the potential neuroprotection provided by antagonists of cholinergic muscarinic and glutamate N-methyl-d-aspartate (NMDA) receptors. The simulator reproduced firing of CA1 hippocampal neurons triggered by exposure to paraoxon (POX), as found in patch-clamp recordings in in vitro mouse hippocampal slices. In the case of POX intoxication, it predicted a preventing action of the muscarinic receptor antagonist atropine sulfate, as well as a synergistic action with the non-competitive NMDA receptor antagonist memantine. These in silico predictions relative to beneficial effects of atropine sulfate combined with memantine were recapitulated experimentally in an in vivo model of POX in adult male Swiss mice using electroencephalic (EEG) recordings. Thus, our simulator is a new powerful tool to identify protective therapeutic strategies against OP central effects, by screening various combinations of muscarinic and NMDA receptor antagonists. PMID:27108687

  19. Experimental evidence for drought induced alternative stable states of soil moisture.

    PubMed

    Robinson, David A; Jones, Scott B; Lebron, Inma; Reinsch, Sabine; Domínguez, María T; Smith, Andrew R; Jones, Davey L; Marshall, Miles R; Emmett, Bridget A

    2016-01-25

    Ecosystems may exhibit alternative stable states (ASS) in response to environmental change. Modelling and observational data broadly support the theory of ASS, however evidence from manipulation experiments supporting this theory is limited. Here, we provide long-term manipulation and observation data supporting the existence of drought induced alternative stable soil moisture states (irreversible soil wetting) in upland Atlantic heath, dominated by Calluna vulgaris (L.) Hull. Manipulated repeated moderate summer drought, and intense natural summer drought both lowered resilience resulting in shifts in soil moisture dynamics. The repeated moderate summer drought decreased winter soil moisture retention by ~10%. However, intense summer drought, superimposed on the experiment, that began in 2003 and peaked in 2005 caused an unexpected erosion of resilience and a shift to an ASS; both for the experimental drought manipulation and control plots, impairing the soil from rewetting in winter. Measurements outside plots, with vegetation removal, showed no evidence of moisture shifts. Further independent evidence supports our findings from historical soil moisture monitoring at a long-term upland hydrological observatory. The results herald the need for a new paradigm regarding our understanding of soil structure, hydraulics and climate interaction.

  20. Experimental investigation on vortex-induced vibration of steel catenary riser

    NASA Astrophysics Data System (ADS)

    Fan, Yu-ting; Mao, Hai-ying; Guo, Hai-yan; Liu, Qing-hai; Li, Xiao-min

    2015-10-01

    Steel catenary riser (SCR) is the transmission device between the seabed and the floating production facilities. As developments move into deeper water, the fatigue life of the riser can become critical to the whole production system, especially due to the vortex-induced vibration (VIV), which is the key factor to operational longevity. As a result, experimental investigation about VIV of the riser was performed in a large plane pool which is 60 m long, 36 m wide and 6.5 m deep. Experiments were developed to study the influence of current speed and seabed on VIV of SCR. The results show that amplitudes of strain and response frequencies increase with the current speed both in cross-flow (CF) and in-line (IL). When the current speed is high, multi-mode response is observed in the VIV motion. The amplitudes of strain in IL direction are not much smaller than those in CF direction. The seabed has influence on the response frequencies of riser and the positions of damage for riser.

  1. Gravity-induced coating flows of vaginal gel formulations: in vitro experimental analysis.

    PubMed

    Kieweg, Sarah L; Geonnotti, Anthony R; Katz, David F

    2004-12-01

    Efficacy of topical microbicidal drug delivery formulations against HIV depends in part on their coating distributions and retention on vaginal epithelium. This study focused on gravity-induced coating flows of vaginal gels, and effects of formulation composition and surface wettability on coating. We hypothesized that presence of a yield stress, and surface wettability, affect coating. Experiments imaged and analyzed coating flows of gels on inclined model hydrophilic or hydrophobic surfaces. The in vitro wettability conditions bracket those believed to exist on vaginal epithelium in vivo. Six commercial vaginal gels were studied: three polyacrylic acid-based (PAA) and three cellulose-based. Our research group uses these gels in complementary human in vivo studies and other in vitro experimental analyses; this study is a first step in linking the in vivo and in vitro measurements. Coating by PAA gels was different from cellulose-based gels: the former exhibited yield stresses, which prevented initial gel shape from deforming during sliding. Coating flows of cellulose gels depended upon surface wettability. The slipping rates of the PAA gels ranked inversely with fitted yield stress values. The coating flow rates of the cellulose gels (hydrophilic surface) did not correlate with consistency index, but ranked inversely with the shear-thinning index. This study introduces a simple methodology for comparing trial formulations and relating their flows to gel constituents and physical properties. It also suggests differences in coating by current commercial gels.

  2. [A study of epidermal alterations induced by PCDF on experimental carcinogenesis].

    PubMed

    Hirose, R; Hori, M; Toyoshima, H; Shukuwa, T; Udono, M; Yoshida, H

    1991-05-01

    An effect of 2,3,4,7,8-pentachlorodibenzofuran (PCDF) as a promoter on a course of experimental skin carcinogenesis in mice by chemicals 20-methylcholanthrene (MC) has been proved by our previous studies. Details of ultrastructural epidermal alterations induced by MC and PCDF were observed and an attempt to differentiate benign tumor from malignant one in which a combined application of MC and PCDF on mice skin resulted was done electron microscopically. Four significant findings as follows were detected. First of all even the epidermal cells without tumor had some atypicality. Secondly both of benign tumor and normal-appeared skin without tumor had giant and round-shaped keratohyalin granules (KHGs) which show a tendency of less keratinization. Thirdly cytoplasmic projections of epidermal cells increased in number and sparse tonofilaments scattered in the cytoplasm of benign tumor. This is also an appearance of mucous metaplasia of keratinocytes as well as the form of KHGs mentioned above. Finally benign tumor had thick horny cells including numerous lipid droplets, and that is a sign of acceleration of epidermal turn over. Since epidermal cells have little chance to be exposed to carcinogens when they quickly keratinize, they rarely form a cancer. When epidermal cells have such tendency as less keratinization or more keratinization, they are supposed to be less sensitive to any stimuli of carcinogens, and consequently they incline to be benign tumor instead of malignant one. PMID:1916594

  3. Numerical and experimental study of the thermal stress of silicon induced by a millisecond laser

    SciTech Connect

    Wang Xi; Qin Yuan; Wang Bin; Zhang Liang; Shen Zhonghua; Lu Jian; Ni Xiaowu

    2011-07-20

    A spatial axisymmetric finite element model of single-crystal silicon irradiated by a 1064 nm millisecond laser is used to investigate the thermal stress damage induced by a millisecond laser. The transient temperature field and the thermal stress field for 2 ms laser irradiation with a laser fluence of 254 J/cm{sup 2} are obtained. The numerical simulation results indicate that the hoop stresses along the r axis on the front surface are compressive stress within the laser spot and convert to tensile stress outside the laser spot, while the radial stresses along the r axis on the front surface and on the z axis are compressive stress. The temperature of the irradiated center is the highest temperature obtained, yet the stress is not always highest during laser irradiation. At the end of the laser irradiation, the maximal hoop stress is located at r=0.5 mm and the maximal radial stress is located at r=0.76 mm. The temperature measurement experiments are performed by IR pyrometer. The numerical result of the temperature field is consistent with the experimental result. The damage morphologies of silicon under the action of a 254 J/cm{sup 2} laser are inspected by optical microscope. The cracks are observed initiating at r=0.5 mm and extending along the radial direction.

  4. Numerical and experimental study of the thermal stress of silicon induced by a millisecond laser.

    PubMed

    Wang, Xi; Qin, Yuan; Wang, Bin; Zhang, Liang; Shen, Zhonghua; Lu, Jian; Ni, Xiaowu

    2011-07-20

    A spatial axisymmetric finite element model of single-crystal silicon irradiated by a 1064 nm millisecond laser is used to investigate the thermal stress damage induced by a millisecond laser. The transient temperature field and the thermal stress field for 2 ms laser irradiation with a laser fluence of 254 J/cm(2) are obtained. The numerical simulation results indicate that the hoop stresses along the r axis on the front surface are compressive stress within the laser spot and convert to tensile stress outside the laser spot, while the radial stresses along the r axis on the front surface and on the z axis are compressive stress. The temperature of the irradiated center is the highest temperature obtained, yet the stress is not always highest during laser irradiation. At the end of the laser irradiation, the maximal hoop stress is located at r=0.5 mm and the maximal radial stress is located at r=0.76 mm. The temperature measurement experiments are performed by IR pyrometer. The numerical result of the temperature field is consistent with the experimental result. The damage morphologies of silicon under the action of a 254 J/cm(2) laser are inspected by optical microscope. The cracks are observed initiating at r=0.5 mm and extending along the radial direction. PMID:21772353

  5. Protective effects of D-002 on experimentally induced gastroesophageal reflux in rats

    PubMed Central

    Zamora, Zullyt; Molina, Vivian; Mas, Rosa; Ravelo, Yazmin; Perez, Yohany; Oyarzabal, Ambar

    2014-01-01

    AIM: To investigate the effects of beeswax alcohols (D-002) on the esophageal damage induced by gastroesophageal reflux (GER) in rats. METHODS: Sixty male rats were randomized into six groups (10 rats/group): a negative control and five groups with experimentally induced GER: a positive vehicle control, three treated with D-002 (25, 100 and 200 mg/kg, respectively), and one with omeprazole 10 mg/kg. All treatments were given by gastric gavage. One hour after dosing, GER was produced by simultaneous ligation of the pyloric end and the forestomach. Esophageal lesions index (ELI), gastric secretion volume and acidity, and esophageal malondialdehyde (MDA) and sulfhydryl (SH) group concentrations were measured. Statistical significance was considered at P < 0.05. RESULTS: As compared to the negative control, the positive control group exhibited increased ELI (5.2 ± 0.33 vs 0 ± 0, P = 0.0003), gastric secretion volume (2.69 ± 0.09 vs 0.1 ± 0.0, P = 0.0003) and acidity (238 ± 19.37 vs 120.0 ± 5.77, P = 0.001), and esophageal concentrations of MDA (2.56 ± 0.1 vs 1.76 ± 0.28, P = 0.001) and SH groups (1.02 ± 0.05 vs 0.56 ± 0.08, P = 0.0003). D-002 (25, 100 and 200 mg/kg) reduced ELI (3.36 ± 0.31, 2.90 ± 0.46 and 2.8 ± 0.23, respectively) vs the positive control (5.2 ± 0.33) (P = 0.004; P = 0.002; P = 0.001, respectively). There were no significant changes in acidity with D-002 treatment, and only the highest dose reduced the volume of the gastric secretion (1.92 ± 0.25) vs the positive control (2.69 ± 0.09, P = 0.013). D-002 (25, 100 and 200 mg/kg) lowered the esophageal MDA (2.05 ± 0.16, 1.98 ± 0.22 and 1.93 ± 0.22, respectively) (P = 0.01; P = 0.03; P = 0.03, respectively) and SH group concentration (0.87 ± 0.06, 0.79 ± 0.08 and 0.77 ± 0.06, respectively) (P = 0.04; P = 0.04; P = 0.02) vs the positive control (2.56 ± 0.10 and 1.02 ± 0.05, respectively). Omeprazole decreased ELI (2.54 ± 0.47), gastric secretion volume (1.97 ± 0.14) and acidity

  6. Defining the Minimal Important Difference for the Visual Analogue Scale Assessing Dyspnea in Patients with Malignant Pleural Effusions

    PubMed Central

    Mishra, Eleanor K.; Corcoran, John P.; Hallifax, Robert J.; Stradling, John; Maskell, Nicholas A.; Rahman, Najib M.

    2015-01-01

    Background The minimal important difference (MID) is essential for interpreting the results of randomised controlled trials (RCTs). Despite a number of RCTs in patients with malignant pleural effusions (MPEs) which use the visual analogue scale for dyspnea (VASD) as an outcome measure, the MID has not been established. Methods Patients with suspected MPE undergoing a pleural procedure recorded their baseline VASD and their post-procedure VASD (24 hours after the pleural drainage), and in parallel assessed their breathlessness on a 7 point Likert scale. Findings The mean decrease in VASD in patients with a MPE reporting a ‘small but just worthwhile decrease’ in their dyspnea (i.e. equivalent to the MID) was 19mm (95% CI 14-24mm). The mean drainage volume required to produce a change in VASD of 19mm was 760ml. Interpretation The mean MID for the VASD in patients with a MPE undergoing a pleural procedure is 19mm (95% CI 14-24mm). Thus choosing an improvement of 19mm in the VASD would be justifiable in the design and analysis of future MPE studies. PMID:25874452

  7. Activation of adenosine A2A receptors by polydeoxyribonucleotide increases vascular endothelial growth factor and protects against testicular damage induced by experimental varicocele in rats.

    PubMed

    Minutoli, Letteria; Arena, Salvatore; Bonvissuto, Giulio; Bitto, Alessandra; Polito, Francesca; Irrera, Natasha; Arena, Francesco; Fragalà, Eugenia; Romeo, Carmelo; Nicotina, Piero Antonio; Fazzari, Carmine; Marini, Herbert; Implatini, Alessandra; Grimaldi, Silvia; Cantone, Noemi; Di Benedetto, Vincenzo; Squadrito, Francesco; Altavilla, Domenica; Morgia, Giuseppe

    2011-03-15

    In rat experimental varicocele, polydeoxyribonucleotide (PDRN) induces vascular endothelial growth factor (VEGF) production, thereby enhancing testicular function. This may point to a new therapeutic approach in human varicocele.

  8. COMPARISON OF LUNG ATTENUATION AND HETEROGENEITY BETWEEN CATS WITH EXPERIMENTALLY INDUCED ALLERGIC ASTHMA, NATURALLY OCCURRING ASTHMA AND NORMAL CATS.

    PubMed

    Masseau, Isabelle; Banuelos, Alina; Dodam, John; Cohn, Leah A; Reinero, Carol

    2015-01-01

    Airway remodeling is a prominent feature of feline allergic asthma but requires biopsy for characterization. Computed tomography (CT) has appeal as a minimally invasive diagnostic test. The purpose of this prospective case-control study was to compare indices of airway remodeling between cats with experimentally induced, spontaneous asthma and healthy unaffected cats using CT. We hypothesized that experimental and spontaneous feline asthma would have similar CT airway remodeling characteristics and that these would be significantly different in healthy cats. Experimentally induced asthmatic research cats (n = 5), spontaneously asthmatic pet cats (n = 6), and healthy research cats (n = 5) were scanned unrestrained using a 64-detector row CT scanner. Inspiratory breath-hold CT scans were also performed in experimentally induced asthmatic and healthy cats. Mean ± extent variation of lung attenuation for each cat was determined using an airway inspector software program and CT images were scored for lung heterogeneity by a board-certified veterinary radiologist who was unaware of cat group status. Groups were compared using one-way ANOVA (unrestrained scans) and the Student's t-test (anesthetized scans) with significance defined as P < 0.10. Experimentally asthmatic and spontaneously asthmatic cats had significantly (P = 0.028 and P = 0.073, respectively) increased lung attenuation compared to healthy cats. Heterogeneity scores were higher in experimentally induced asthmatic cat than in healthy cats. Objective quantification of lung heterogeneity and lung volume did not differ among the three groups (P = 0.311, P = 0.181, respectively). Findings supported our hypothesis. Inspiratory breath-hold anesthetized CT scans facilitated discrimination between asthmatic and healthy cats in comparison to unrestrained CT scans.

  9. The influence of age and genetics on natural resistance to experimentally induced feline infectious peritonitis.

    PubMed

    Pedersen, Niels C; Liu, Hongwei; Gandolfi, Barbara; Lyons, Leslie A

    2014-11-15

    Naturally occurring feline infectious peritonitis (FIP) is usually fatal, giving the impression that immunity to the FIP virus (FIPV) is extremely poor. This impression may be incorrect, because not all cats experimentally exposed to FIPV develop FIP. There is also a belief that the incidence of FIP may be affected by a number of host, virus, and environmental cofactors. However, the contribution of these cofactors to immunity and disease incidence has not been determined. The present study followed 111 random-bred specific pathogen free (SPF) cats that were obtained from a single research breeding colony and experimentally infected with FIPV. The cats were from several studies conducted over the past 5 years, and as a result, some of them had prior exposure to feline enteric coronavirus (FECV) or avirulent FIPVs. The cats were housed under optimized conditions of nutrition, husbandry, and quarantine to eliminate most of the cofactors implicated in FIPV infection outcome and were uniformly challenge exposed to the same field strain of serotype 1 FIPV. Forty of the 111 (36%) cats survived their initial challenge exposure to a Type I cat-passaged field strains of FIPV. Six of these 40 survivors succumbed to FIP to a second or third challenge exposure, suggesting that immunity was not always sustained. Exposure to non-FIP-inducing feline coronaviruses prior to challenge with virulent FIPV did not significantly affect FIP incidence but did accelerate the disease course in some cats. There were no significant differences in FIP incidence between males and females, but resistance increased significantly between 6 months and 1 or more years of age. Genetic testing was done on 107 of the 111 infected cats. Multidimensional scaling (MDS) segregated the 107 cats into three distinct families based primarily on a common sire(s), and resistant and susceptible cats were equally distributed within each family. Genome-wide association studies (GWAS) on 73 cats that died of FIP

  10. Experimental investigation of flow-induced vibration on isolated and tandem circular cylinders fitted with strakes

    NASA Astrophysics Data System (ADS)

    Korkischko, I.; Meneghini, J. R.

    2010-05-01

    The effect of varying the geometric parameters of helical strakes on vortex-induced vibration (VIV) is investigated in this paper. The degree of oscillation attenuation or even suppression is analysed for isolated circular cylinder cases. How a cylinder fitted with strakes behaves when immersed in the wake of another cylinder in tandem arrangement is also investigated and these results are compared to those with a single straked cylinder. The experimental tests are conducted at a circulating water channel facility and the cylindrical models are mounted on a low-damping air bearing elastic base with one degree-of-freedom, restricted to oscillate in the transverse direction to the channel flow. Three strake pitches (p) and heights (h) are tested: p=5, 10, 15d, and h=0.1, 0.2, 0.25d. The mass ratio is 1.8 for all models. The Reynolds number range is from 1000 to 10 000, and the reduced velocity varies up to 21. The cases with h=0.1d strakes reduce the amplitude response when compared to the isolated plain cylinder, however the oscillation still persists. On the other hand, the cases with h=0.2, 0.25d strakes almost completely suppress VIV. Spanwise vorticity fields, obtained through stereoscopic digital particle image velocimetry (SDPIV), show an alternating vortex wake for the p=10d and h=0.1d straked cylinder. The p=10d and h=0.2d cylinder wake has separated shear layers with constant width and no roll-up close to the body. The strakes do not increase the magnitude of the out-of-plane velocity compared to the isolated plain cylinder. However, they deflect the flow in the out-of-plane direction in a controlled way, which can prevent the vortex shedding correlation along the span. In order to investigate the wake interference effect on the strake efficiency, an experimental arrangement with two cylinders in tandem is employed. The centre-to-centre distance for the tandem arrangement varies from 2 to 6. When the downstream p=10d and h=0.2d cylinder is immersed in the

  11. Experimental Animal Models for Studies on the Mechanisms of Blast-Induced Neurotrauma

    PubMed Central

    Risling, Mårten; Davidsson, Johan

    2012-01-01

    A blast injury is a complex type of physical trauma resulting from the detonation of explosive compounds and has become an important issue due to the use of improvised explosive devices (IED) in current military conflicts. Blast-induced neurotrauma (BINT) is a major concern in contemporary military medicine and includes a variety of injuries that range from mild to lethal. Extreme forces and their complex propagation characterize BINT. Modern body protection and the development of armored military vehicles can be assumed to have changed the outcome of BINT. Primary blast injuries are caused by overpressure waves whereas secondary, tertiary, and quaternary blast injuries can have more varied origins such as the impact of fragments, abnormal movements, or heat. The characteristics of the blast wave can be assumed to be significantly different in open field detonations compared to explosions in a confined space, such an armored vehicle. Important parameters include peak pressure, duration, and shape of the pulse. Reflections from walls and armor can make the prediction of effects in individual cases very complex. Epidemiological data do not contain information of the comparative importance of the different blast mechanisms. It is therefore important to generate data in carefully designed animal models. Such models can be selective reproductions of a primary blast, penetrating injuries from fragments, acceleration movements, or combinations of such mechanisms. It is of crucial importance that the physical parameters of the employed models are well characterized so that the experiments can be reproduced in different laboratory settings. Ideally, pressure recordings should be calibrated by using the same equipment in several laboratories. With carefully designed models and thoroughly evaluated animal data it should be possible to achieve a translation of data between animal and clinical data. Imaging and computer simulation represent a possible link between experiments

  12. The influence of age and genetics on natural resistance to experimentally induced feline infectious peritonitis.

    PubMed

    Pedersen, Niels C; Liu, Hongwei; Gandolfi, Barbara; Lyons, Leslie A

    2014-11-15

    Naturally occurring feline infectious peritonitis (FIP) is usually fatal, giving the impression that immunity to the FIP virus (FIPV) is extremely poor. This impression may be incorrect, because not all cats experimentally exposed to FIPV develop FIP. There is also a belief that the incidence of FIP may be affected by a number of host, virus, and environmental cofactors. However, the contribution of these cofactors to immunity and disease incidence has not been determined. The present study followed 111 random-bred specific pathogen free (SPF) cats that were obtained from a single research breeding colony and experimentally infected with FIPV. The cats were from several studies conducted over the past 5 years, and as a result, some of them had prior exposure to feline enteric coronavirus (FECV) or avirulent FIPVs. The cats were housed under optimized conditions of nutrition, husbandry, and quarantine to eliminate most of the cofactors implicated in FIPV infection outcome and were uniformly challenge exposed to the same field strain of serotype 1 FIPV. Forty of the 111 (36%) cats survived their initial challenge exposure to a Type I cat-passaged field strains of FIPV. Six of these 40 survivors succumbed to FIP to a second or third challenge exposure, suggesting that immunity was not always sustained. Exposure to non-FIP-inducing feline coronaviruses prior to challenge with virulent FIPV did not significantly affect FIP incidence but did accelerate the disease course in some cats. There were no significant differences in FIP incidence between males and females, but resistance increased significantly between 6 months and 1 or more years of age. Genetic testing was done on 107 of the 111 infected cats. Multidimensional scaling (MDS) segregated the 107 cats into three distinct families based primarily on a common sire(s), and resistant and susceptible cats were equally distributed within each family. Genome-wide association studies (GWAS) on 73 cats that died of FIP

  13. Experimental animal models for studies on the mechanisms of blast-induced neurotrauma.

    PubMed

    Risling, Mårten; Davidsson, Johan

    2012-01-01

    A blast injury is a complex type of physical trauma resulting from the detonation of explosive compounds and has become an important issue due to the use of improvised explosive devices (IED) in current military conflicts. Blast-induced neurotrauma (BINT) is a major concern in contemporary military medicine and includes a variety of injuries that range from mild to lethal. Extreme forces and their complex propagation characterize BINT. Modern body protection and the development of armored military vehicles can be assumed to have changed the outcome of BINT. Primary blast injuries are caused by overpressure waves whereas secondary, tertiary, and quaternary blast injuries can have more varied origins such as the impact of fragments, abnormal movements, or heat. The characteristics of the blast wave can be assumed to be significantly different in open field detonations compared to explosions in a confined space, such an armored vehicle. Important parameters include peak pressure, duration, and shape of the pulse. Reflections from walls and armor can make the prediction of effects in individual cases very complex. Epidemiological data do not contain information of the comparative importance of the different blast mechanisms. It is therefore important to generate data in carefully designed animal models. Such models can be selective reproductions of a primary blast, penetrating injuries from fragments, acceleration movements, or combinations of such mechanisms. It is of crucial importance that the physical parameters of the employed models are well characterized so that the experiments can be reproduced in different laboratory settings. Ideally, pressure recordings should be calibrated by using the same equipment in several laboratories. With carefully designed models and thoroughly evaluated animal data it should be possible to achieve a translation of data between animal and clinical data. Imaging and computer simulation represent a possible link between experiments

  14. Biological studies on the effect of estrogen on experimentally induced asthma in mice.

    PubMed

    El-Desouki, Nabila I; Tabl, Ghada A; Elkhodary, Yasmin A A

    2016-01-01

    This study evaluates the influence of estrogen hormone on the experimentally induced asthma in male mice. The animals were divided into four groups, with 20 mice in each group; group I (control mice) included mice that received no treatment, group II included mice that received intraperitoneal estrogen injection (0.25 mg/kg body weight (bw), twice on day 28 of the experiment), group III (asthmatic mice) included asthmatic mice that received intraperitoneal injection of two doses of ovalbumin (OVA; 2 µg of OVA mixed with 100 µg of aluminum potassium sulfate) on days 1 and 14 of the experiment and then challenged intranasally with a single dose of OVA (50 µg dissolved in 0.05 ml phosphate-buffered saline; PBS) on day 28 of the experiment, and group IV (asthmatic mice treated with estrogen) included asthma model male mice that received the estrogen (0.5 mg/kg bw in 40 ml PBS, twice on the day 28 of the experiment). The immunohistochemical studies observed a marked intensity of CD15 immunoreactivity in the lung tissues of asthma model mice. Physiological results recorded that the total and differential count of leukocytes in bronchoalveolar lavage fluid (BALF) of asthma model mice recorded a significant increase in the number of leukocytes especially in the number of eosinophil cells. The BALF of asthma model mice showed high levels of interleukins 4 and 5 (IL-4 and IL-5), and there was a significant decrease in both the levels of IL-4 and IL-5 in BALF of asthma model mice treated with estrogen. In conclusion, the obtained results indicated that the asthma is responsible for certain immunohistochemical and physiological alterations induced in lung tissues of mice. The administration of estrogen to asthmatic male mice could improve these changes. For this reason, the present findings support the possible role of estrogen in modulating the inflammatory effects caused by asthma in male mice and may be helpful to cure many asthmatic progressions.

  15. The role of Allium cepa on aluminum-induced reproductive dysfunction in experimental male rat models

    PubMed Central

    Ige, Serah F; Akhigbe, Roland E

    2012-01-01

    AIM: Reproductive toxicity is a major challenge associated with aluminum (Al) exposure. Studies that associated Al with reproductive dysfunction did not account for the possible influence of Allium cepa extract. This study, therefore, investigates the influence of A. cepa on aluminum-induced reproductive dysfunction. MATERIALS AND METHODS: Six male rats per group were assigned to one of the following four treatment groups: The control animals were on control diet. A. cepa-treated rats received 1 ml of the extract/100 g body weight (BW), Al-treated rats received 100 mg AlCl3 /kg BW, and A.cepa+Al received 1 ml of the extract/100 g BW plus 100 mg AlCl3 /kg BW. Rats were orally administered their respective doses. A. cepa treatment was for 8 weeks, while Al treatment was for the last 3 days of the experimental period. RESULTS: Results obtained showed that Al significantly decreased (P < 0.05) plasma testosterone, follicular stimulating hormone (FSH), luteinizing hormone (LH), sperm count, motility, morphology and viability, superoxide dismutase (SOD) and catalase (CAT) activities, while lipid peroxidation index [malondialdehyde (MDA)] was significantly (P < 0.05) increased. Reproductive hormones (except testosterone), sperm qualities, and enzymatic antioxidants were significantly (P < 0.05) increased in A. cepa-treated rats and A. cepa plus Al-treated rats, while MDA was significantly (P < 0.05) improved. Weights of testes were comparable in all groups. CONCLUSION: It is thus suggested that Al exerts reproductive dysfunction by oxidative damage. A. cepa antagonizes the toxic effects of AlCl3 and improves the antioxidant status and sperm quality of male rat. However, testosterone level did not increase with A. cepa treatment. PMID:23162360

  16. Entamoeba histolytica calreticulin: an endoplasmic reticulum protein expressed by trophozoites into experimentally induced amoebic liver abscesses.

    PubMed

    González, Enrique; de Leon, Maria del Carmen García; Meza, Isaura; Ocadiz-Delgado, Rodolfo; Gariglio, Patricio; Silva-Olivares, Angelica; Galindo-Gómez, Silvia; Shibayama, Mineko; Morán, Patricia; Valadez, Alicia; Limón, Angelica; Rojas, Liliana; Hernández, Eric G; Cerritos, René; Ximenez, Cecilia

    2011-02-01

    Entamoeba histolytica calreticulin (EhCRT) is remarkably immunogenic in humans (90-100% of invasive amoebiasis patients). Nevertheless, the study of calreticulin in this protozoan is still in its early stages. The exact location, biological functions, and its role in pathogenesis are yet to be fully understood. The aim of the present work is to determine the location of EhCRT in virulent trophozoites in vivo and the expression of the Ehcrt gene during the development of experimentally induced amoebic liver abscesses (ALA) in hamsters. Antibodies against recombinant EhCRT were used for the immunolocalization of EhCRT in trophozoites through confocal microscopy; immunohistochemical assays were also performed on tissue sections of ALAs at different times after intrahepatic inoculation. The expression of the Ehcrt gene during the development of ALA was estimated through both in situ RT-PCR and real-time RT-PCR. Confocal assays of virulent trophozoites showed a distribution of EhCRT in the cytoplasmic vesicles of different sizes. Apparently, EhCRT is not exported into the hepatic tissue. Real-time RT-PCR demonstrated an over-expression of the Ehcrt gene at 30 min after trophozoite inoculation, reaching a peak at 1-2 h; thereafter, the expression fell sharply to its original levels. These results demonstrate for the first time in an in vivo model of ALA, the expression of Ehcrt gene in E. histolytica trophozoites and add evidence that support CRT as a resident protein of the ER in E. histolytica species. The in vivo experiments suggest that CRT may play an important role during the early stages of the host-parasite relationship, when the parasite is adapting to a new environment, although the protein seems to be constitutively synthesized. Moreover, trophozoites apparently do not export EhCRT into the hepatic tissue in ALA.

  17. Glycyrrhizin ameliorates metabolic syndrome-induced liver damage in experimental rat model.

    PubMed

    Sil, Rajarshi; Ray, Doel; Chakraborti, Abhay Sankar

    2015-11-01

    Glycyrrhizin, a major constituent of licorice (Glycyrrhiza glabra) root, has been reported to ameliorate insulin resistance, hyperglycemia, dyslipidemia, and obesity in rats with metabolic syndrome. Liver dysfunction is associated with this syndrome. The objective of this study is to investigate the effect of glycyrrhizin treatment on metabolic syndrome-induced liver damage. After induction of metabolic syndrome in rats by high fructose (60%) diet for 6 weeks, the rats were treated with glycyrrhizin (50 mg/kg body weight, single intra-peritoneal injection). After 2 weeks of treatment, rats were sacrificed to collect blood samples and liver tissues. Compared to normal, elevated activities of serum alanine transaminase, alkaline phosphatase and aspartate transaminase, increased levels of liver advanced glycation end products, reactive oxygen species, lipid peroxidation, protein carbonyl, protein kinase Cα, NADPH oxidase-2, and decreased glutathione cycle components established liver damage and oxidative stress in fructose-fed rats. Activation of nuclear factor κB, mitogen-activated protein kinase pathways as well as signals from mitochondria were found to be involved in liver cell apoptosis. Increased levels of cyclooxygenase-2, tumor necrosis factor, and interleukin-12 proteins suggested hepatic inflammation. Metabolic syndrome caused hepatic DNA damage and poly-ADP ribose polymerase cleavage. Fluorescence-activated cell sorting using annexin V/propidium iodide staining confirmed the apoptotic hepatic cell death. Histology of liver tissue also supported the experimental findings. Treatment with glycyrrhizin reduced oxidative stress, hepatic inflammation, and apoptotic cell death in fructose-fed rats. The results suggest that glycyrrhizin possesses therapeutic potential against hepatocellular damage in metabolic syndrome. PMID:26400710

  18. Alterations of testosterone metabolism in microsomes from rats with experimental colitis induced by dextran sulfate sodium.

    PubMed

    Huang, Yanjuan; Hu, Nan; Gao, Xuejiao; Yan, Zhixiang; Li, Sai; Jing, Wanghui; Yan, Ru

    2015-05-01

    Down-regulation of some hepatic cytochrome P450s (CYP450s) was observed in patients and animals with ulcerative colitis (UC). This study examined changes of CYP450s activities in microsomes of liver (RLMs), intestine (RIMs) and kidney (RRMs) from rats with experimental acute colitis induced by 5% dextran sulfate sodium (DSS) for 7days and those receiving DSS treatment followed by 7-d cessation through measuring 6α-(CYP1A1), 7α-(CYP2A1), 16α-(CYP2C11) and 2β-/6β-(CYP3A2) hydroxytestosterone (OHT) formed from testosterone. Both pro-(IL-1β, IL-6, TNF-α) and anti-(IL-4, IL-10) inflammatory cytokines were elevated in acute colitis, while the production of the former was enhanced and that of the latter declined by DSS withdrawal. In RLMs, the CYP2A1 activity was significantly increased at DSS stimulation and partially returned to normal level when DSS treatment was terminated. Activity of other CYP450s were decreased by acute colitis and remained after DSS withdrawal. In RRMs, formations of 6α-, 16α- and 2β-OHT significantly declined in acute colitis and DSS termination further potentiated the down-regulation, while 7α-OHT formation was suppressed at DSS stimulation and remained after DSS withdrawal. The formation of 6β-OHT only showed significant decrease after DSS withdrawal. Two metabolites (6α- and 6β-OHT) formed in RIMs and 6β-OHT formation was significantly decreased by DSS stimulation and continued after DSS treatment halted. These findings indicate that the alterations of CYP450s activities vary with organ, CYP isoforms and colitis status, which arouse cautions on efficacy and toxicity of drug therapy during disease progression.

  19. A new modified animal model of myosin-induced experimental autoimmune myositis enhanced by defibrase

    PubMed Central

    Wen-Jing, Luo; Hong-Hua, Li; Xiang-Hui, Lu; Jie-Xiao, Liu

    2015-01-01

    Introduction We investigated the effect of defibrase (a proteolytic enzyme extraction of Agkistrodon halys venom) on experimental autoimmune myositis (EAM) in guinea pigs and explored the option of using a modified pig model of EAM to enhance the study of this disease. Material and methods Guinea pigs were divided into 3 groups: group A (control group) was immunized with complete Freund adjuvant (CFA), then received 6 injections of saline weekly; group B (EAM group) was immunized with partially purified rabbit myosin emulsified with CFA, then received an injection of saline; group C (EAM + defibrase group) was immunized with purified rabbit myosin emulsified with CFA, then received an injection of defibrase. The animals were observed for their general health condition and the body weight was measured daily. Plasma levels of fibrinogen and creatine kinase (CK) were determined. Muscle tissues were examined histologically. Results After immunizations for 6 weeks, incidence of EAM in groups A, B and C was 0 (0/7), 83.3% (10/12) and 100% (15/15), respectively. Guinea pigs with EAM presented angeitis symptoms of muscle weakness. Histological analysis revealed a significant difference. Muscles with EAM had scattered or diffuse inflammatory manifestations, which are also common pathological features of human idiopathic polymyositis (IPM). Defibrase-treated animals displayed extensive inflammation and fiber necrosis compared with the EAM group (histological score: 2.80 ±1.15 vs. 1.88 ±1.32, p < 0.05). Severity of inflammation of group B was mainly mild to moderate; 16.7% (2/12) of animals developed severe inflammation. Incidence of severe inflammation with a score up to 4 in group C was 40% (6/15). Conclusions Defibrase can exacerbate myosin-induced EAM; thus a new modified model was generated. PMID:26788090

  20. Experimental study of the Richtmyer-Meshkov instability induced by a Mach 3 shock wave

    SciTech Connect

    BP Puranik; JG Oakley; MH Anderson; R Bonaazza

    2003-11-12

    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.

  1. Temperature dependence of spectral induced polarization data: experimental results and membrane polarization theory

    NASA Astrophysics Data System (ADS)

    Bairlein, Katharina; Bücker, Matthias; Hördt, Andreas; Hinze, Björn

    2016-04-01

    Spectral induced polarization measurements are affected by temperature variations due to a variety of temperature-dependent parameters that control the complex electrical conductivity. Most important is the influence of the ion mobility, which increases with increasing temperature. It is responsible for the increase of the conductivity of the fluid in the pores with temperature and influences the electrical double layer on the mineral surface. This work is based on laboratory measurements of 13 sandstone samples from different sources with different geological and petrophysical characteristics. We measured the complex impedance in a frequency range from 0.01 to 100 Hz and a temperature range from 0 to 40 °C. The main observation is a decrease of the characteristic time (defined by the inverse of the frequency, at which the phase shift is maximum) with increasing temperature. The strength of this decrease differs from one sample to another. The temperature dependence of the phase shift magnitude cannot easily be generalized, as it depends on the particular sample. The experimental findings suggest that neglecting the influence of temperature on complex conductivity may lead to significant errors when estimating hydraulic conductivity from relaxation time. We also simulate the temperature dependence with a theoretical model of membrane polarization and review some of the model properties, with an emphasis on the temperature dependence of the parameters. The model reproduces several features characterizing the measured data, including the temperature dependence of the characteristic times. Computed tomography and microscope images of the pore structure of three samples also allow us to associate differences in the geometrical parameters used in the modelling with pore scale parameters of the actual samples.

  2. Psychological and cortisol reactivity to experimentally induced stress in adults with ADHD.

    PubMed

    Raz, Sivan; Leykin, Dmitry

    2015-10-01

    Individuals with ADHD suffer from increased vulnerability to environmental and mental stressors and may be at increased risk for chronic stress in everyday life. The Hypothalamic-Pituitary-Adrenal (HPA) axis is a critical physiological system that mediates responses to stress. The present study seeks to examine test performance, test anxiety, self-reported psychological stress and cortisol reactivity to mental-cognitive stress in adults with ADHD when compared with healthy controls. Stress was induced by an arithmetic ability test. Psychological stress was assessed repeatedly throughout the experimental session. Salivary cortisol, an indicator of the HPA axis function, was evaluated immediately upon arrival, as well as 1 min and 20 min post-test completion. Results revealed higher levels of test anxiety and poorer performance on the test in the ADHD group. The ADHD and control groups showed no difference in base-line levels of subjective stress and in subjective stress levels 20 min after the test. In contrast, individuals with ADHD reported significantly higher levels of stress at the test anticipation phase and 1 min post-test completion. Cortisol response to stress differed according to group: in the ADHD group, 20 min post-test cortisol levels were significantly higher than base-line cortisol levels. This was not evident in the control group. These results suggest greater activation of the HPA axis in response to stress in adults with ADHD when compared with healthy controls. Adults with ADHD do not differ from controls in basal levels of subjective stress and cortisol, but do have stronger psychophysiological reactions in response to stressful challenges. The present findings are among the first to demonstrate significant alterations in cortisol reactivity to stress in adults with ADHD.

  3. Contractile profile of esophageal and gastric fundus strips in experimental doxorubicin-induced esophageal atresia.

    PubMed

    Capeto, F A; Lima, F J B; Okoba, W; Ramos, F L; Messias, T F A; Rigonatto, G A; Sbragia, L; Magalhães, P J C; Melo-Filho, A A

    2015-05-01

    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 (P<0.05). The maximum effect values (Emax) for DOXO+EA and DOXO-EA were significantly lower than control (P<0.05), but the half-maximal effective concentration (EC50) values were not significantly different when the three groups were compared (P>0.05). 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.

  4. Contractile profile of esophageal and gastric fundus strips in experimental doxorubicin-induced esophageal atresia

    PubMed Central

    Capeto, F.A.; Lima, F.J.B.; Okoba, W.; Ramos, F.L.; Messias, T.F.A.; Rigonatto, G.A.; Sbragia, L.; Magalhães, P.J.C.; Melo-Filho, A.A.

    2015-01-01

    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 (P<0.05). The maximum effect values (Emax) for DOXO+EA and DOXO-EA were significantly lower than control (P<0.05), but the half-maximal effective concentration (EC50) values were not significantly different when the three groups were compared (P>0.05). 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. PMID:25760030

  5. Restoration of micturition using microelectric current in experimentally induced spastic urinary bladder in rabbits.

    PubMed

    Karoutas, G; Karacostas, D; Artemis, N; Liapis, J; Tzotzoras, T; Andreou, A; Tsitsopoulos, P

    1988-12-01

    The 29 rabbits used in this study were divided into three groups, A (A1 and A2), B, and C. In subgroup A1, 4 animals were used in order to verify whether the contact of an electrode to the sacral nerves results in some abnormality of voiding reflex. In subgroups A1 and A2 (4 animals each) we further studied the micturition function using three parameters: (i) urinary bladder fluoroscopy and radiography, (ii) cystomanometry, and (iii) electromyography of the pelvic floor muscles (external sphinter). In group B (9 rabbits) spastic paraplegia and micturition disturbances resulted from spinal cord compression that was induced by inserting a balloon catheter into the T11-T12 intervertebral foramen. In this group the parameters studied revealed a spastic urinary bladder in all animals. Finally, the 12 animals of group C were rendered paraplegic as described in group B, and microelectrodes were placed over the sacral nerves as in subgroup A1. By applying a specific sequence of sacral nerve stimulation we succeeded in satisfactory urinary bladder emptying as confirmed by the micturition parameters studied: The urinary bladder pressure decreased from 65 +/- 3 to 28 +/- 3 mm Hg. The pelvic floor muscle amplitude was lowered from 130 +/- 7 to 20 +/- 3 microV, and finally the radiological bladder size also decreased from 38 cm2 before voiding to 18 +/- 3 cm2 after voiding. These results indicate that microelectric current stimulation of the sacral nerves, when applied under a specific sequence, could rather satisfactorily restore micturition disturbances, at least in this experimental animal.

  6. Computational and experimental study of flow-induced vibration of the SSME main injector post

    SciTech Connect

    Chen, S.S.; Jendrzejczyk, J.A.; Wambsganss, M.W.

    1986-01-01

    The Space Shuttle Main Engine (SSME) liquid-oxygen (LOX) posts are subjected to high-velocity turbulent flow from the transfer ducts. In a preliminary assessment of the vibration problem, it was determined that the two potential excitation mechanisms for LOX post vibration are fluidelastic instability and turbulent buffeting. A fundamental study is being conducted to understand the problem and to develop techniques to avoid detrimental vibrational effects with the objective of improving engine life. This paper summarizes the results of an analytical model for fluidelastic instability and test results for turbulent buffeting of a tube array in crossflow. A general theory of fluidelastic instability for a tube array in crossflow is presented. Various techniques to obtain the motion-dependent fluid-force coefficients are discussed and the general instability characteristics are summarized. The theory is also used to evaluate the results of other mathematical models for crossflow-induced instability. The fluid excitation forces acting on a tube array are presented as a function of Reynolds number, incoming flow conditions, and tube location in an array. The experimental data show the general characteristics of flow across a tube array. As the flow passes through each row of tubes, the fluid is subjected to resistance, the effect of which is to convert some of the fluid pressure energy to turbulent energy. In the first few rows, the transformation of energy occurs in a somewhat orderly manner. As the flow reaches the interior tubes, unsteadiness of the flow increases and, usually, a randomness of the flow and its pressure fluctuation exists in the flow field.

  7. Respiratory syncytial virus promotes Moraxella catarrhalis-induced ascending experimental otitis media.

    PubMed

    Brockson, M Elizabeth; Novotny, Laura A; Jurcisek, Joseph A; McGillivary, Glen; Bowers, Martha R; Bakaletz, Lauren O

    2012-01-01

    Otitis media (OM) is a polymicrobial disease wherein prior or concurrent infection with an upper respiratory tract virus plays an essential role, predisposing the middle ear to bacterial invasion. In episodes of acute bacterial OM, respiratory syncytial virus (RSV) is the most commonly isolated virus and thus serves as an important co-pathogen. Of the predominant bacterial agents of OM, the pathogenesis of disease due to Moraxella catarrhalis is the least well understood. Rigorous study of M. catarrhalis in the context of OM has been significantly hindered by lack of an animal model. To bridge this gap, we assessed whether co-infection of chinchillas with M. catarrhalis and RSV would facilitate ascension of M. catarrhalis from the nasopharynx into the middle ear. Chinchillas were challenged intranasally with M. catarrhalis followed 48 hours later by intranasal challenge with RSV. Within 7 days, 100% of nasopharynges were colonized with M. catarrhalis and homogenates of middle ear mucosa were also culture-positive. Moreover, within the middle ear space, the mucosa exhibited hemorrhagic foci, and a small volume of serosanguinous effusion was present in one of six ears. To improve upon this model, and based on epidemiologic data, nontypeable Haemophilus influenzae (NTHI) was included as an additional bacterial co-pathogen via intranasal administration four days before M. catarrhalis challenge. With this latter protocol, M. catarrhalis was cultured from the nasopharynx and middle ear homogenates of a maximum of 88% and 79% animals, respectively, for up to 17 days after intranasal challenge with M. catarrhalis. Additionally, hemorrhagic foci were observed in 79% of middle ears upon sacrifice. Thus, these data demonstrated that co-infection with RSV and NTHI predisposed to M. catarrhalis-induced ascending experimental OM. This model can be used both in studies of pathogenesis as well as to investigate strategies to prevent or treat OM due to M. catarrhalis.

  8. Combination treatment of lycopene and hesperidin protect experimentally induced ulcer in laboratory rats

    PubMed Central

    Jain, Dilpesh; Katti, Neha

    2015-01-01

    Aim: Lycopene, a carotenoid and hesperidin, a flavonoid are naturally occurring in vegetables and fruits. Synergistic effect of a combination of carotenoid and flavonoid has been reported due to its antioxidant activity. Therefore, the present study was aimed to evaluate the protective effect of this combination on pylorus ligation induced ulcers in rats. Materials and Methods: Thirty Wistar albino rats were divided into five groups (n = 6). Rats were fasted for 24 h before pylorus ligation. After 24 h of fasting the rats were treated with hesperidin (100 mg/kg) and lycopene (2 mg/kg) and their combination 1h prior to surgery. After an hour under ether anesthesia pylorus ligation was performed, after 5 h the animals were sacrificed, stomach was dissected, and gastric contents were collected and measured. Total acidity and pH of gastric content was estimated. Ulcer index was calculated, and macroscopic examination of the stomach was carried out. Results: The sham operated rats showed a significant increase in pH, volume of gastric content and total acidity and ulcer index. The rats pretreated with lycopene and hesperidin showed significant improvement in the ulcer conditions. However, rats treated with a combination of lycopene and hesperidin showed more significant restoration of gastric function as compared to sham operated rats. Moreover, a significant difference was also noted in rats treated with a combination as compared to lycopene and hesperidin treatment alone. Conclusion: Thus experimentally the combination was seen to treat ulcers by anti-secretory, neutralizing, cytoprotective and mainly due to its antioxidant property. PMID:26401402

  9. Silymarin ameliorates memory deficits and neuropathological changes in mouse model of high-fat-diet-induced experimental dementia.

    PubMed

    Neha; Kumar, Amit; Jaggi, Amteshwar S; Sodhi, Rupinder K; Singh, Nirmal

    2014-08-01

    A huge body evidences suggest that obesity is the single great risk factor for the development of dementia. Recently, silymarin, a flavonoid, clinically in use as a hepatoprotectant, has been reported to prevent amyloid beta-induced memory impairment by reducing oxidative stress and inflammation in mice brain. However, its potential in high-fat-diet (HFD)-induced dementia has not yet been investigated. Therefore, the present study is designed to explore the role of silymarin in HFD-induced experimental dementia in mice. Morris water maze test was employed to assess learning and memory. Various biochemical estimations including brain acetylcholinerstarse activity (AchE), thiobarbituric acid-reactive species (TBARS) level, reduced glutathione level (GSH), nirate/nitrite, and myeloperoxidase (MPO) activity were measured. Serum cholesterol level was also determined. HFD significantly impaired the cognitive abilities, along with increasing brain AchE, TBARS, MPO, nitrate/nitrite, and serum cholesterol levels. Marked reduction of brain GSH levels was observed. On the contrary, silymarin significantly reversed HFD-induced cognitive deficits and the biochemical changes. The present study indicates strong potential of silymarin in HFD-induced experimental dementia.

  10. Body mass index, airflow obstruction and dyspnea and body mass index, airflow obstruction, dyspnea scores, age and pack years-predictive properties of new multidimensional prognostic indices of chronic obstructive pulmonary disease in primary care

    PubMed Central

    Ansari, Khalid; Keaney, Niall; Kay, Andrea; Price, Monica; Munby, Joan; Billett, Andrew; Haggerty, Sharon; Taylor, Ian K.; Al Otaibi, Hajed

    2016-01-01

    BACKGROUND: The assessment of the severity of chronic obstructive pulmonary disease (COPD) should involve a multidimensional approach that is now clearly shown to be better than using spirometric impairment alone. The aim of this study is to validate and compare novel tools without an exercise test and to extend prognostic value to patients with less severe impairment of Forced expiratory volume 1 s. METHODS: A prospective, observational, primary care cohort study identified 458 eligible patients recruited from the primary care clinics in the northeast of England in 1999–2002. A new prognostic indicator – body mass index, airflow obstruction and dyspnea (BOD) together with the conventional prognostic indices age, dyspnea and airflow obstruction (ADO), global initiative for chronic obstructive lung disease (GOLD) and new GOLD matrix were studied. We also sought to improve prognostication of BOD by adding age (A) and smoking history as pack years (S) to validate BODS (BOD with smoking history) and BODAS (BOD with smoking history and age) as prognostic tools and the predictive power of each was analyzed. RESULTS: The survival of the 458 patients was assessed after a median of 10 years when the mortality was found to be 33.6%. The novel indices BOD, BODS, and BODAS were significantly predictive for all-cause mortality in our cohort. Furthermore with ROC analysis the C statistics for BOD, BODS, and BODAS were 0.62, 0.66, and 0.72, respectively (P < 0.001 for each), whereas ADO and GOLD stages had a C statistic of 0.70 (P < 0.001) and 0.56 (P < 0.02), respectively. GOLD Matrix was not significant in this cohort. CONCLUSION: BOD, BODS, and BODAS scores are validated predictors of all-cause mortality in a primary care cohort with COPD. PMID:27803752

  11. Experimental Assessment and Enhancement of Planar Laser-Induced Fluorescence Measurements of Nitric Oxide in an Inverse Diffusion Flame

    NASA Technical Reports Server (NTRS)

    Partridge, William P.; Laurendeau, Normand M.

    1997-01-01

    We have experimentally assessed the quantitative nature of planar laser-induced fluorescence (PLIF) measurements of NO concentration in a unique atmospheric pressure, laminar, axial inverse diffusion flame (IDF). The PLIF measurements were assessed relative to a two-dimensional array of separate laser saturated fluorescence (LSF) measurements. We demonstrated and evaluated several experimentally-based procedures for enhancing the quantitative nature of PLIF concentration images. Because these experimentally-based PLIF correction schemes require only the ability to make PLIF and LSF measurements, they produce a more broadly applicable PLIF diagnostic compared to numerically-based correction schemes. We experimentally assessed the influence of interferences on both narrow-band and broad-band fluorescence measurements at atmospheric and high pressures. Optimum excitation and detection schemes were determined for the LSF and PLIF measurements. Single-input and multiple-input, experimentally-based PLIF enhancement procedures were developed for application in test environments with both negligible and significant quench-dependent error gradients. Each experimentally-based procedure provides an enhancement of approximately 50% in the quantitative nature of the PLIF measurements, and results in concentration images nominally as quantitative as LSF point measurements. These correction procedures can be applied to other species, including radicals, for which no experimental data are available from which to implement numerically-based PLIF enhancement procedures.

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

    SciTech Connect

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

    2009-05-15

    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.

  13. Experimental measurement of surface temperatures during flame-jet induced thermal spallation

    NASA Astrophysics Data System (ADS)

    Wilkinson, M. A.; Tester, J. W.

    1993-01-01

    temperature measurements and heat flux determination during laser and flame-jet induced thermal spallation are used to provide appropriate values of the “Weibull parameters” that statistically describe the size-strength relationship in granite. Use of these parameters allows one to accurately estimate surface temperatures required by the numerical simulation model to calculate heat and mass transport rates occurring in the flow field above the spalling rock surface. Based on the results of this experimental study, we concluded that mechanically-determined Weibull parameters are not directly applicable to describe spallation failure phenomena caused by thermal stress. Under the extreme rapid heating conditions of flame-jet drilling, local overheating and possibly stress relief lead to higher temperatures than predicted using room temperature Weibull parameters. Nonetheless, the Weibull-based statistical model of failure can be utilized by empirically fitting the m and σ0 Weibull parameters to match experimental measurements of spalling surface temperature as a function of applied heat flux. Correlations for steady state and onset spallation conditions were established with consistent results obtained for both laser and propane-oxygen flame jet heating.

  14. Arsenic-induced phosphate limitation under experimental Early Proterozoic oceanic conditions

    NASA Astrophysics Data System (ADS)

    Chi Fru, Ernest; Hemmingsson, Christoffer; Holm, Mikaela; Chiu, Beverly; Iñiguez, Enrique

    2016-01-01

    Comparison of phosphorus concentrations associated with modern hydrothermal Fe(III)(oxyhydr)oxides and ancient Fe(III) oxide-rich iron formations, is used to estimate bioavailable Precambrian marine phosphorus (P) concentrations. This led to the proposition of a low dissolved P budget of ˜10-25% of present-day levels, before ˜1.9 billion years ago. Estimates incorporating ancient marine Si levels ≥ 0.67 mM instead suggested global dissolved P levels greater than today. Here we unite current experimental models that have considered NaCl solutions containing elevated dissolved Fe(II), Si, Ca2+ and Mg2+ ions in the incorporation of P in Precambrian marine Fe(III)(oxyhydr)oxides, in addition to arsenic as a hydrothermal proxy. We show that the coprecipitation of dissolved P and Fe(III)(oxyhydr)oxides from arsenic-rich marine waters produces an average P distribution coefficient of ˜0.072 (± 0.01) μM-1. This is comparable to the ˜ 0.07 μM-1 predicted for Fe(III)(oxyhydr)oxides in modern arsenic-rich, submarine hydrothermal settings, from which the lower Early Proterozoic dissolved marine P concentrations were predicted. As/P molar ratios below modern seawater ratios removed the negative feedback effect high Si impose on P scavenging by Fe(III)(oxyhydr)oxides. The binding of As(III) to Fe(III)(oxyhydr)oxides exhibits a lower competitive influence on P fixation. As(V) that likely became prominent in the surficially oxidized Early Proterozoic oceans induced dissolved P limitation because of preferential P sequestration at the expense of dissolved As(V) enrichment. The control of As on P scavenging by the precipitating Fe(III)(oxyhydr)oxides is strong regardless of common seawater cations (Mg2+ and Ca2+). The data suggest that the application of Si and Fe(III)(oxyhydr)oxides as an ancient seawater P proxy should consider chemical variability between depositional basins, taking into account the rather strong role hydrothermal arsenic has on the distribution of P in

  15. Experimental study of blast-induced traumatic brain injury using a physical head model.

    PubMed

    Zhang, Jiangyue; Pintar, Frank A; Yoganandan, Narayan; Gennarelli, Thomas A; Son, Steven F

    2009-11-01

    This study was conducted to quantify intracranial biomechanical responses and external blast overpressures using physical head model to understand the biomechanics of blast traumatic brain injury and to provide experimental data for computer simulation of blast-induced brain trauma. Ellipsoidal-shaped physical head models, made from 3-mm polycarbonate shell filled with Sylgard 527 silicon gel, were used. Six blast tests were conducted in frontal, side, and 45 degrees oblique orientations. External blast overpressures and internal pressures were quantified with ballistic pressure sensors. Blast overpressures, ranging from 129.5 kPa to 769.3 kPa, were generated using a rigid cannon and 1.3 to 3.0 grams of pentaerythritol tetranitrate (PETN) plastic sheet explosive (explosive yield of 13.24 kJ and TNT equivalent mass of 2.87 grams for 3 grams of material). The PETN plastic sheet explosive consisted of 63% PETN powder, 29% plasticizer, and 8% nitrocellulose with a density of 1.48 g/cm3 and detonation velocity of 6.8 km/s. Propagation and reflection of the shockwave was captured using a shadowgraph technique. Shockwave speeds ranging from 423.3 m/s to 680.3 m/s were recorded. The model demonstrated a two-stage response: a pressure dominant (overpressure) stage followed by kinematic dominant (blast wind) stage. Positive pressures in the brain simulant ranged from 75.1 kPa to 1095 kPa, and negative pressures ranged from -43.6 kPa to -646.0 kPa. High- and normal-speed videos did not reveal observable deformations in the brain simulant from the neutral density markers embedded in the midsagittal plane of the head model. Amplitudes of the internal positive and negative pressures were found to linearly correlate with external overpressure. Results from the current study suggested a pressure-dominant brain injury mechanism instead of strain injury mechanism under the blast severity of the current study. These quantitative results also served as the validation and calibration

  16. An evaluation of the clinical pathologic findings in experimentally induced urinary bladder rupture in pre-ruminant calves.

    PubMed Central

    Wilson, D G; MacWilliams, P S

    1998-01-01

    The purpose of this project was to study the biochemical abnormalities that develop over time in preruminant calves with experimentally induced uroperitoneum. Uroperitoneum was produced by incising the bladder via a standing left flank laparotomy. Serum and peritoneal concentrations sodium, chloride, potassium, phosphate and creatinine were determined at 0, 2, 4, 8, 24, and 40 h. Serum creatinine concentration was increased by 8 h post-bladder rupture. Peritoneal concentrations of potassium and phosphate were significantly elevated 2 h after bladder rupture and peritoneal creatinine was significantly elevated by 4 h. Serum to peritoneal fluid ratios for potassium, phosphate and creatinine exceeded 2:1 within 2 h of bladder rupture. Pre-ruminant calves with experimentally induced uroperitoneum did not become hyperkalemic during the 40 h experiment. PMID:9553714

  17. Experimental investigation of effects of jet decay rate on jet-induced pressures on a flat plate: Tabulated data

    NASA Technical Reports Server (NTRS)

    Kuhlman, J. M.; Ousterhout, D. S.; Warcup, R. W.

    1978-01-01

    Tabular data are presented for an experimental study of the effects of jet decay rate on the jet-induced pressure distribution on a flat plate for a single jet issuing at right angle to the flat plate into a uniform crossflow. The data are presented in four sections: (1) presents the static nozzle calibration data; (2) lists the plate surface static pressure data and integrated loads; (3) lists the jet centerline trajectory data; and (4) lists the centerline dynamic pressure data.

  18. Evaluation of safety and protective effects of Potentilla fulgens root extract in experimentally induced diarrhea in mice

    PubMed Central

    Tangpu, Vareishang; Deori, Khirod; Yadav, Arun Kumar

    2014-01-01

    Aim: The roots of Potentilla fulgens Wall. ex Hook. (Rosaceae) have been used in the indigenous system of medicine in Northeast India to treat diarrhea. The aim of this study was to investigate the safety and protective effects of P. fulgens root extract in experimentally induced diarrhea in mice. Materials and Methods: The protective effects of P. fulgens root extract was investigated against experimentally induced diarrhea in mice, using four experimental models, that is the measurement of fecal 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 (100-3200 mg/kg). In addition, the serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, 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 antidiarrheal tests, administration of 800 mg/kg dose of extract to mice showed 50% protection from diarrhea evoked by castor oil. In addition, the extract also showed 29.27% reduction in PGE2-induced intestinal secretion as compared with 30.31% recorded for loperamide, a standard antidiarrheal drug. Conclusions: The results of this study indicate that P. fulgens root extract possesses significant antidiarrheal properties. Therefore, the roots of this plant can be an effective traditional medicine for protection from diarrhea. PMID:26401356

  19. Changes in urinary bone resorption markers (pyridinoline, deoxypyridinoline) resulting from experimentally-induced osteoarthritis in the temporomandibular joint of rats.

    PubMed

    Imada, Masae; Tanimoto, Kotaro; Ohno, Shigeru; Sasaki, Akiko; Sugiyama, Hiroki; Tanne, Kazuo

    2003-01-01

    The purpose of this study was to quantify the urinary bone resorption markers, pyridinoline (Pyr) and deoxypyridinoline (Dpyr), excreted from experimentally-induced osteoarthritis (OA) in the temporomandibular joint (TMJ) of rats. Osteoarthritic lesions were induced by intra-articular injection of collagenase into the right TMJs of 16-week-old male rats. The whole day's urine was collected from each animal one day before the injection and 5, 7, 11 and 14 days after the injection. Urine samples were analyzed by high-perfomance liquid chromatography and fluorescence spectroscopy. Histological changes in condyle were examined by using paraffin sections with toluidine blue staining. Degenerative changes were observed in the articular cartilage of the experimental group on day 7 and day 14 after the injection of collagenase. The concentration of Pyr was remarkably high in the experimental group, and consequently the Pyr to Dpyr ratio was significantly higher (p<0.05) in the experimental group than in the control group from 7-14 days after the injection. These findings suggest that a urinary Pyr/Dpyr ratio would be available for the detection of degenerative changes in condyle relevant to temporomandibular joint osteoarthritis (TMJ OA). PMID:12555930

  20. Numerical and experimental study on flow-induced noise at blade-passing frequency in centrifugal pumps

    NASA Astrophysics Data System (ADS)

    Yang, Jun; Yuan, Shouqi; Yuan, Jianping; Si, Qiaorui; Pei, Ji

    2014-05-01

    With the increasing noise pollution, low noise optimization of centrifugal pimps has become a hot topic. However, experimental study on this problem is unacceptable for industrial applications due to unsustainable cost. A hybrid method that couples computational fluid dynamics (CFD) with computational aeroacoustic software is used to predict the flow-induced noise of pumps in order to minimize the noise of centrifugal pumps in actual projects. Under Langthjem's assumption that the blade surface pressure is the main flow-induced acoustic source in centrifugal pumps, the blade surface pressure pulsation is considered in terms of the acoustical sources and simulated using CFX software. The pressure pulsation and noise distribution in the near-cutoff region are examined for the blade-passing frequency (BPF) noise, and the sound pressure level (SPL) reached peaks near the cutoff that corresponded with the pressure pulsation in this region. An experiment is performed to validate this prediction. Four hydrophones are fixed to the inlet and outlet ports of the test pump to measure the flow-induced noise from the four-port model. The simulation results for the noise are analyzed and compared with the experimental results. The variation in the calculated noise with changes in the flow agreed well with the experimental results. When the flow rate was increased, the SPL first decreased and reached the minimum near the best efficient point (BEP); it then increased when the flow rate was further increased. The numerical and experimental results confirmed that the BPF noise generated by a blade-rotating dipole roughly reflects the acoustic features of centrifugal pumps. The noise simulation method in current study has a good feasibility and suitability, which could be adopted in engineering design to predict and optimize the hydroacoustic behavior of centrifugal pumps.

  1. Systemic administration of antigen-pulsed dendritic cells induces experimental allergic asthma in mice upon aerosol antigen rechallenge.

    PubMed

    Graffi, Sebastian J; Dekan, Gerhard; Stingl, Georg; Epstein, Michelle M

    2002-05-01

    Antigen-pulsed dendritic cells (DCs) have been used extensively as cellular vaccines to induce a myriad of protective immune responses. Adoptive transfer of antigen-pulsed DCs is especially effective at generating Th1 and CD8 immune responses. However, recently this strategy has been shown to induce Th2 cells when DCs are administered locally into the respiratory tract. We sought to address whether systemic rather than local antigen-pulsed DC administration could induce Th2 experimental allergic asthma. We found that OVA-pulsed splenic DCs injected intraperitoneally induced polarized Th2 allergic lung disease upon secondary OVA aerosol challenge. Disease was characterized by eosinophilic lung inflammation, excess mucus production, airway hyperresponsiveness, and OVA-specific IgG1 and IgE. In addition, unusual pathology characterized by macrophage alveolitis and multinucleated giant cells was observed. These data show that systemic administration of antigen-pulsed DCs and subsequent aeroantigen challenge induces Th2 immunity. These findings have important implications for the development of DC-based vaccines.

  2. Effect of the Angiotensin I Converting Enzyme Inhibitor, MK-421, on Experimentally Induced Drinking

    NASA Technical Reports Server (NTRS)

    Fregley, Melvin J.; Fater, Dennis C.; Greenleaf, John E.

    1982-01-01

    MK-421, the ethyl ester maleate salt of N-(S)-1-(ethoxycarbonyl)-3-phenyl-propyl- Ala-L-Pro, is an angiotensin I converting enzyme inhibitor. An initial objective was to determine whether MK-421, administered at 0, 2.5, 5.0, 10.0, 20.0 and 40.0 mg/kg, ip to 96 female rats 15 min prior to administration of the beta-adrenergic agonist, isoproterenol (25 microgram/kg, ip), would inhibit the drinking induced by isoproterenol during 2 h after its administration. The water intake induced by isoproterenol was inhibited significantly by 2.5 mg MK-421/kg. When a similar experiment was performed using Angiotensin I (AI) (200 microgram/kg, ip) as the dipsogenic agent, MK-421 (5 mg/kg, ip), administered 15 min prior to AI, inhibited significantly both the dipsogenic and the diuretic effect of AI. However, administration of angiotensin II (AII, 200 microgram/kg, ip) 15 min after MK-421 (5mg/kg) was accompanied by a water intake that did not differ from AII alone. The drink induced by ip administration of 1.0 m NaCl solution (1% of body wt, ip) was not inhibited by administration of MK-421 (5 mg/kg) 15 min prior to allowing access to water while the drink induced by a 24 h dehydration was partially inhibited. Thus, the drinks induced by administraition of either isoproterenol or AI are dependent on formation of AII. That induced by dehydration is partially dependent, while that induced by hypertonic siilinc is independent of the formation of AII.

  3. Nicorandil inhibits neutrophil recruitment in carrageenan-induced experimental pleurisy in mice.

    PubMed

    Matsui, Tamires C; Coura, Giovanna M E; Melo, Ivo S F; Batista, Carla R A; Augusto, Paulo Sérgio A; Godin, Adriana M; Araújo, Débora P; César, Isabela C; Ribeiro, Lucas S; Souza, Danielle G; Klein, André; de Fátima, Ângelo; Machado, Renes R; Coelho, Márcio M

    2015-12-15

    Nicorandil is a drug characterized by the coupling of a nitric oxide (NO) donor to nicotinamide. We have previously demonstrated that nicotinamide exhibits activity in different models of pain and inflammation. Now, we investigated the effects induced by per os (p.o.) administration of nicorandil (25, 50 or 100mg/Kg) on neutrophil recruitment in a carrageenan-induced model of pleurisy in mice. Effects induced by nicorandil (100mg/kg) were compared with those induced by equimolar doses of nicotinamide (58mg/kg) and N-(2-hydroxyethyl)-nicotinamide (NHN; 79mg/kg). We also investigated whether effects on the production of inflammatory mediators play a role in the activity of nicorandil. P.o. nicorandil, 0.5h before and 1h after the i.pl. injection of carrageenan, reduced neutrophil recruitment. However, equimolar doses of nicotinamide or NHN failed to induce such effect. Single treatment (previous or late) with nicorandil (100mg/Kg, p.o.) also reduced neutrophils recruitment, although to a lesser extent when compared to the double treatment. Nicorandil reduced the concentrations of interleukin-1β, CXCL-1 and prostaglandin E2 in the pleural exudate. Concluding, we demonstrated the activity of nicorandil in a model of pleurisy induced by carrageenan. This activity was characterized by reduction of the neutrophil accumulation and inhibition of production of inflammatory mediators. The effects induced by nicorandil on the leukocytes recruitment and production of inflammatory mediators contribute to a better understanding of its clinical benefits and indicate that these benefits may be due to its vasodilating and anti-inflammatory activities. PMID:26607465

  4. Nondestructive prediction of point source pyroshock response spectra based on experimental conditioning of laser-induced shocks

    NASA Astrophysics Data System (ADS)

    Jang, Jae-Kyeong; Lee, Jung-Ryul

    2014-09-01

    Pyroshock can easily cause failures in electronic and optical components that are sensitive to high-frequency energy. Pyroshock is generated during explosive-based pyrotechnical events, such as the separation of boosters from a space shuttle and the separation of satellites from a space launcher. Therefore, the prediction of high-frequency structural response, particularly the shock response spectrum (SRS), is important for safe operation of pyrotechnical devices. In general, real explosive testing using distributed accelerometers is widely used. This paper proposes a technology to replace the expensive, dangerous, low-repeatability explosive test with a laser-induced shock test based on a laser beam and in-line filter conditioning. This method does not use any special numerical signal processing. Two different experiments based on explosive and laser excitation were performed with a 2-mm thick aluminum plate. The optimum laser-induced shock experimental conditions to predict real pyroshock were investigated while considering the size, energy, and fluence of the laser beam as parameters. The similarity of the SRS of the laser-induced shock to that of the real explosive pyroshock was evaluated based on the mean acceleration difference (MAD, %). The experimentally determined optimal conditions were also applied to four points on the path of a pyroshock propagation. To match the SRS at each point, the laser-induced shock was amplified, for which three different gain concepts are proposed: the initial gain, optimized gain, and constant gain. The proposed technology enables nondestructive pyro SRS prediction by conditioning the laser-induced shock to obtain an SRS with high similarity to the real pyroshock.

  5. [Experimental study on the fabrication of bioactive membrane for inducing bone regeneration].

    PubMed

    Tian, Weidong; Bao, Chongyun; Liu, Lei; Tang, Wei; Zheng, Xiaohui; Li, Shengwei; Xiong, Chengdong

    2004-10-01

    The aim of this study was to develop a bioactive membrane for inducing bone regeneration. The membrane was composed of polylactic acid, collagen, recombinant human bone morphogenetic protein-2 (rhBMP-2). The PLA + collagen + rhBMP-2 membrane was fabricated by solvent-casting and cool-drying. The mechanic properties of this compound membrane were tested. The two surfaces of membrane were observed by SEM. Degradability of PLA was evaluated by SEM observation and molecular weight measure in vitro and in vivo. The compound membranes were implanted in rabbit muscles. The samples were obtained when animals were sacrificed at different periods: 2 weeks, 1, 2, 3, 6 months after surgery. The biodegradability and biocompatibility of the membrane were evaluated. The heterotopic bone inducing activity of BMP was identified. The results indicated that the strength at extension to failure of the compound membrane was 36.4MPa at 2.3% strain. The compound membrane was found bearing active factor on its coarse side, which can induce bone regeneration. After implantation in vivo, the membrane maintained the structure for three months and degraded in 6 months. Based on histological analysis, there was no obvious inflammation. Heterotopic bone was induced. We could conclude that the PLA + collagen + rhBMP-2 membrane is an absorbable compound membrane that possesses good biocompatibility, adequate mechanic properties and excellent property of bone induction. It could be applied as an ideal membrane for inducing bone regeneration. PMID:15553872

  6. Experimental investigation of film cooling flow induced by shaped holes on a turbine blade.

    PubMed

    Barthet, S; Bario, F

    2001-05-01

    The present study is the second half of a piece of work carried out in collaboration with SNECMA. It investigates shaped hole film cooling, numerically and experimentally. The aim of this paper is the experimental analysis of shaped hole film cooling on a large scale turbine blade (1.4 m chord). The test section is a large scale turbine inlet guide vane cascade. The test airfoil is equipped with a row of nine 50 degrees sloped shaped holes. They are located on the suction side at 20% of the curvilinear length of the blade from the stagnation point. The inlet film cooling hole diameter is 12 mm. The jet flow is heated to 55 degrees C above the crossflow temperature. Velocity and temperature field measurements have been done to obtain mean and fluctuating values. The results are compared to those obtained by Béral on the same experimental apparatus and in the same test conditions, for a row of cylindrical holes.

  7. Effect of rosiglitazone in sodium arsenite-induced experimental vascular endothelial dysfunction.

    PubMed

    Kaur, Tajpreet; Goel, Rajesh Kumar; Balakumar, Pitchai

    2010-04-01

    The present study has been designed to investigate the effect of rosiglitazone, a peroxisome proliferator activated receptor gamma agonist in sodium arsenite-induced vascular endothelial dysfunction (VED) in rats. The rats were administered sodium arsenite (1.5 mg/kg/day, i.p., 2 weeks) to induce VED. The development of VED was assessed by employing isolated aortic ring preparation and estimating serum nitrite/nitrate concentration. Further, the integrity of the aortic endothelium was assessed histologically using haematoxylin-eosin staining. Moreover, the oxidative stress was assessed by estimating serum thiobarbituric acid reactive substances, aortic reactive oxygen species and reduced form of glutathione. The administration of sodium arsenite produced VED by impairing acetylcholine-induced endothelium dependent relaxation, diminishing the integrity of vascular endothelium and decreasing the serum nitrite/nitrate concentration. In addition, sodium arsenite was noted to produce oxidative stress as it increased serum thiobarbituric acid reactive substances and aortic reactive oxygen species and consequently decreased glutathione. Treatment with rosiglitazone (3 mg/kg/day, p.o., 2 weeks and 5 mg/kg/day, p.o., 2 weeks) significantly prevented sodium arsenite-induced VED by enhancing acetylcholine-induced endothelium dependent relaxation, improving the integrity of vascular endothelium, increasing the nitrite/nitrate concentration and decreasing the oxidative stress. However, the vascular protective effect of rosiglitazone was markedly abolished by co-administration of nitric oxide synthase inhibitor, N-Omega-Nitro-L-Arginine Methyl Ester (L-NAME) (25 mg/kg/day, i.p., 2 weeks). Thus, it may be concluded that rosiglitazone reduces oxidative stress, activates eNOS and enhances the generation of nitric oxide to prevent sodium arsenite-induced VED in rats. PMID:20422371

  8. Thalidomide ameliorates cisplatin-induced nephrotoxicity by inhibiting renal inflammation in an experimental model.

    PubMed

    Amirshahrokhi, Keyvan; Khalili, Ali-Reza

    2015-04-01

    Cisplatin is a platinum-based chemotherapy drug. However, its chemotherapeutic use is restricted by serious side effects, especially nephrotoxicity. Inflammatory mechanisms have a significant role in the pathogenesis of cisplatin-induced nephrotoxicity. Thalidomide is an immunomodulatory and anti-inflammatory agent and is used for the treatment of various inflammatory diseases. The purpose of this study was to investigate the potential nephroprotective effect of thalidomide in a mouse model of cisplatin-induced nephrotoxicity. Nephrotoxicity was induced in mice by a single injection of cisplatin (15 mg/kg, i.p.) and treated with thalidomide (50 and 100 mg/kg/day, orally) for 4 days, beginning 24 h prior to the cisplatin injection. Renal toxicity induced by cisplatin was demonstrated by increasing plasma levels of creatinine and blood urea nitrogen (BUN). Cisplatin increased the renal production of the proinflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and transforming growth factor (TGF)-β1. In addition, kidney levels of malondialdehyde (MDA), myeloperoxidase (MPO), and nitric oxide (NO) were increased by cisplatin. Biochemical results showed that thalidomide reduced cisplatin-induced increase in plasma creatinine and BUN. Thalidomide treatment also significantly reduced tissue levels of the proinflammatory cytokines, MDA, MPO, and NO and increased anti-inflammatory cytokine IL-10. Furthermore, histological examination indicated that thalidomide ameliorated renal damage caused by cisplatin. These data suggest that thalidomide attenuates cisplatin-induced nephrotoxicity possibly by inhibition of inflammatory reactions. Taken together, our findings indicate that thalidomide might be a valuable candidate for the prevention of nephrotoxicity in patients receiving cisplatin.

  9. Experimentally Induced Increases in Early Gesture Lead to Increases in Spoken Vocabulary

    ERIC Educational Resources Information Center

    LeBarton, Eve Sauer; Goldin-Meadow, Susan; Raudenbush, Stephen

    2015-01-01

    Differences in vocabulary that children bring with them to school can be traced back to the gestures they produced at the age of 1;2, which, in turn, can be traced back to the gestures their parents produced at the same age (Rowe & Goldin-Meadow, 2009a). We ask here whether child gesture can be experimentally increased and, if so, whether the…

  10. Exogenous surfactant suppresses inflammation in experimental endotoxin-induced lung injury.

    PubMed

    Mittal, Neha; Sanyal, Sankar Nath

    2009-01-01

    Our objective was to evaluate the anti-inflammatory effects of exogenous surfactant and surfactant phospholipids on the lipopolysaccharide (LPS)-induced lung injury. Exogenous surfactant (porcine surfactant) and surfactant phospholipid (dipalmitoyl phospholipid DPPC, hexadecanol, tylaxopol) were instilled intratracheally with LPS in rats. Expression of surfactant apoproteins (SP-A) and the cyclooxygenase enzymes (COX-1 and -2) was studied by immunohistochemistry, and apoptosis was analyzed by in situ terminal dUTP nick end labeling TUNEL assay. The intracellular reactive oxygen species (ROS) was measured in the isolated macrophages by fluorescence measurement with dichlorofluorescein diacetate (DCFH-DA). LPS-induced oxidative burst and apoptosis at 72 hours were reduced by both porcine and synthetic surfactant. SP-A as well as COX-1 and -2 expressions were suppressed with synthetic surfactant treatment, whereas with porcine surfactant (P-SF) the SP-A expression was enhanced in response to LPS administration. These results indicate that exogenous surfactant inhibits LPS-induced inflammation. This anti-inflammatory activity may be an important outcome of surfactant therapy in endotoxin-induced respiratory distress.

  11. Histological Experimental Study on the Effect of Stem Cell Therapy on Adriamycin Induced Chemobrain

    PubMed Central

    El Aziz, Dalia Hussein Abd; Metwally, Hala Gabr

    2013-01-01

    Background and Objectives: Negative consequences of chemotherapy on brain function were suggested and were addressed in animal models as the clinical phenomenon of chemobrain .It was postulated that adriamycin (ADR) induce changes in behaviour and in brain morphology. Human umbilical cord mesenchymal stem cells (HUCMSCs) could be induced to differentiate into neuron-like cells .The present study aimed at investigating the possible therapeutic effect of HUCMSC therapy on adriamycin induced chemobrain in rat. Methods and Results: Twenty five female albino rats were divided into control group, ADR group where rats were given single intraperitoneal (IP) injection of 5 mg/kg ADR. The rats were sacrificed two and four weeks following confirmation of brain damage. In stem cell therapy group, rats were injected with HUCMSCs following confirmation of brain damage and sacrificed two and four weeks after therapy. Brain sections were exposed to histological, histochemical, immunohistochemical and morphometric studies. In ADR group, multiple shrunken neurons exhibiting dark nuclei and surrounded by vacuoles were seen .In response to SC therapy ,multiple normal pyramidal nerve cells were noted. The area of shrunken nerve cells exhibiting dark nuclei, Prussion blue and CD105 positive cells were significantly different in ADR group in comparison to SC therapy group. Conclusions: ADR induced progressive duration dependant cerebral degenerative changes. These changes were ameliorated following cord blood human mesenchymal stem cell therapy. A reciprocal relation was recorded between the extent of regeneration and the existence of undifferentiated mesenchymal stem cells. PMID:24386554

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

    SciTech Connect

    Marcel, Christian P.; Rohde, M.; Van Der Hagen, T.H.J.J.

    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)

  13. In Vitro and in Vivo Experimental Studies on Trabecular Meshwork Degeneration Induced by Benzalkonium Chloride (An American Ophthalmological Society Thesis)

    PubMed Central

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

    2012-01-01

    Purpose: 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. Methods: 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. Results: 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. Conclusion: 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

  14. Inclusion body disease of cranes: comparison of pathologic findings in cranes with acquired vs. experimentally induced disease

    USGS Publications Warehouse

    Schuh, J.C.; Sileo, L.; Siegfried, L.M.; Yuill, Thomas M.

    1986-01-01

    Inclusion body disease of cranes was the cause of death in 17 immature and mature cranes of 5 different species in Wisconsin. A herpesvirus of unknown origin was the apparent cause. An isolate of this herpesvirus was used to experimentally infect 3 species of cranes. Macroscopic and microscopic lesions associated with naturally acquired and experimentally induced disease were essentially identical. Multifocal hepatic and splenic necrosis was found in all cranes evaluated. Necrosis of the gastrointestinal tract, thymus, and bursa of Fabricius also was seen in some of the cranes. Eosinophilic intranuclear inclusion bodies often were commonly associated with hepatic lesions, sometimes with the splenic lesions, and rarely with the thymic or gastrointestinal tract lesions. The lesions of this inclusion body disease were similar to those reported for cranes in Austria from which a crane herpesvirus was isolated.

  15. Minimal involvement of the circumventricular organs in the pathogenesis of spontaneously arising and experimentally induced classical bovine spongiform encephalopathy.

    PubMed

    Sisó, S; Martin, S; Konold, T; Hawkins, S A C; Thurston, L; Simmons, M M; Stack, M J; Jeffrey, M; González, L

    2012-01-01

    In sheep infected experimentally with the bovine spongiform encephalopathy (BSE) agent, amplification of infectivity in peripheral organs during early preclinical stages is thought to contribute to high titres of the agent being detected in blood, with subsequent haematogenous neuroinvasion through the circumventricular organs (CVOs). In contrast, little disease-associated prion protein (PrP(d)) or infectivity is detected in the peripheral tissues of cattle during the preclinical and clinical stages of BSE. The aim of this study was to investigate immunohistochemically the role of haematogenous neuroinvasion in cattle with spontaneously arising and experimentally induced BSE. There was almost complete absence of PrP(d) in the peripheral organs of BSE infected cattle. Additionally, there was minimal involvement of the CVOs during preclinical disease and there was progressive caudorostral accumulation of PrP(d) in the brain. These findings do not support haematogenous neuroinvasion in the bovine disease.

  16. Experimentally induced pigment changes in small African 'Barbus' (Teleostei: Cyprinidae): Synonymy of 'Barbus' amphigramma and 'Barbus' taitensis with 'Barbus' paludinosus

    USGS Publications Warehouse

    Farm, Brian P.

    2001-01-01

    Pigmentation in fishes is known to be variable both among individuals of a species and within individuals over time. Use of pigment characters for taxonomic diagnoses must, therefore, be carefully considered. I present experimental evidence showing that pigment characters previously considered diagnostic for three small African 'Barbus' species may differ between living and preserved specimens and that lasting changes in these characters can be induced experimentally by placing fishes in a different, less turbid environment. Lateral line pigmentation and presence of a spot on the caudal peduncle showed significant changes that resulted in different species identifications before and after the experiment. These pigment patterns are thereby shown to be labile, nontrenchant characters having little or no diagnostic utility. 'Barbus' amphigramma Boulenger, 1903, and 'Barbus' taitensis Gu??nther, 1894, are thus shown to be junior synonyms of 'Barbus' paludinosus Peters, 1852.

  17. Metabolic regulation as a control for lipid disorders. I. Influence of (--)-hydroxycitrate on experimentally induced obesity in the rodent.

    PubMed

    Sullivan, C; Triscari, J

    1977-05-01

    The feasibility of treating obesity by metabolic regulation has been explored in this study by examining the effect of (--)-hydroxycitrate on three types of experimentally induced obesity in the rodent.(--)-Hydroxycitrate was utilized because it depressed fatty acid and cholesterol synthesis in vivo through its activity as a potent competitive inhibitor of APT citrate lyase. In all models, the mature rat, the goldthioglucose-induced obese mouse, and the ventromedial hypothalmic lesioned obese rat, food intake and body weight gain were reduced signficantly by the chronic oral administration of a nontoxic dose of (--)-hydroxcitrate. Body composition analyses of mature rats treated with (--)-hydroxycitrate demonstrated a significant depression of body lipid levels and an unaltered body protein content. However, a citrate administration produced no significant effects on weight gain, food intake, or body lipid or protein levels when compared to controls. PMID:324261

  18. Long-pulse laser-induced damage in an optical anti-reflective film: II. Experimental research

    NASA Astrophysics Data System (ADS)

    Li, Changli; Ma, Yao; Wang, Di; Wang, Zhiyang; Zhang, Xihe; Liu, Haiming

    2014-12-01

    In order to verify the result of theoretical analysis about long-pulse flat-topped multi-Gaussian laser-induced damage in an optical anti-reflection film with HfO2/SiO2 composite film coating on a BK7 substrate (BK7:HfO2/SiO2), an experimental system was built, which carried out the experiment and analysis, focusing on the pulse-length 1.0 ms, flat-topped laser-induced damage. The result shows that the thermal effect is the main reason for damage under the long-pulse flat-topped laser. Moreover, the stripping and shedding occur because of the heating stress of the film happening at an early stage of the laser irradiation. However, the crack happens at laser irradiation termination. The correctness of the theoretical analysis results is verified.

  19. Effect of topical preparation of mycophenolic acid on experimental allergic contact dermatitis of guinea-pigs induced by dinitrofluorobenzene.

    PubMed

    Shoji, Y; Fukumura, T; Kudo, M; Yanagawa, A; Shimada, J; Mizushima, Y

    1994-08-01

    The effects of a topical preparation of mycophenolic acid on the experimental allergic contact dermatitis induced by dinitrofluorobenzene was investigated. Visual assessment of skin reactions showed significant efficacy of a topical preparation of mycophenolic acid. This efficacy appeared from the early stage and endured up to 3 days. Morphological changes in the epidermis and dermis layers of animals treated with a mycophenolic acid cream were moderate compared with that in animals treated with vehicle only. In particular, hyperkeratosis was strongly suppressed. Since suppression of inflammatory cell infiltration was also observed, this efficacy might reach to the epidermis and dermis layer.

  20. Experimental demonstration of coupled-resonator-induced-transparency in silicon-on-insulator based ring-bus-ring geometry.

    PubMed

    Darmawan, S; Tobing, L Y M; Zhang, D H

    2011-08-29

    We experimentally demonstrate coupled-resonator-induced-transparency (CRIT) phenomenon in ring-bus-ring (RBR) geometry synergistically integrated with Mach-Zehnder interferometer (MZI). The RBR consists of two detuned resonators indirectly coupled through a center bus waveguide. The transparency is obtained by increasing the light intercavity interaction through tailoring the RBR phase response while ensuring balanced MZI operation. In this work, a CRIT resonance with a quality factor of ~18,000 is demonstrated with cavity size detuning of ~0.035% and power coupling of ~60%, which are in good agreement with the theory.

  1. Axisymmetric and non-axisymmetric exhaust jet induced effects on a V/STOL vehicle design. Part 3: Experimental technique

    NASA Technical Reports Server (NTRS)

    Schnell, W. C.

    1982-01-01

    The jet induced effects of several exhaust nozzle configurations (axisymmetric, and vectoring/modulating varients) on the aeropropulsive performance of a twin engine V/STOL fighter design was determined. A 1/8 scale model was tested in an 11 ft transonic tunnel at static conditions and over a range of Mach Numbers from 0.4 to 1.4. The experimental aspects of the static and wind-on programs are discussed. Jet effects test techniques in general, fow through balance calibrations and tare force corrections, ASME nozzle thrust and mass flow calibrations, test problems and solutions are emphasized.

  2. Cisplatin-Induced Non-Oliguric Acute Kidney Injury in a Pediatric Experimental Animal Model in Piglets

    PubMed Central

    Lázaro, Alberto; González, Rafael; Urbano, Javier; López, Jorge; Solana, Maria José; Toledo, Blanca; del Castillo, Jimena; Tejedor, Alberto; López-Herce, Jesús

    2016-01-01

    Objective To design an experimental pediatric animal model of acute kidney injury induced by cisplatin. Methods Prospective comparative observational animal study in two different phases. Acute kidney injury was induced using three different doses of cisplatin (2, 3 and 5 mg/kg). The development of nephrotoxicity was assessed 2 to 4 days after cisplatin administration by estimating biochemical parameters, diuresis and renal morphology. Analytical values and renal morphology were compared between 15 piglets treated with cisplatin 3 mg/kg and 15 control piglets in the second phase of the study. Results 41 piglets were studied. The dose of 3 mg/kg administered 48 hours before the experience induced a significant increase in serum creatinine and urea without an increase in potassium levels. Piglets treated with cisplatin 3 mg/kg had significantly higher values of creatinine, urea, phosphate and amylase, less diuresis and lower values of potassium, sodium and bicarbonate than control piglets. Histological findings showed evidence of a dose-dependent increase in renal damage. Conclusions a dose of 3 mg/kg of cisplatin induces a significant alteration in renal function 48 hours after its administration, so it can be used as a pediatric animal model of non-oliguric acute kidney injury. PMID:26871589

  3. Simvastatin ameliorates low-dose streptozotocin-induced type 2 diabetic nephropathy in an experimental rat model.

    PubMed

    Zhang, Siwei; Xu, Huali; Yu, Xiaofeng; Wang, Yuchen; Sun, Fanfan; Sui, Dayuan

    2015-01-01

    The present study aims to study the possible renal protective effect of simvastatin in the development and progression of type 2 diabetic nephropathy. A rat model of T2DN was induced by high-fat diet together with single low-dose of streptozotocin. The diabetic rats were either given treatment or vehicle control for 13 weeks to develop nephropathy. At the end of treatment, parameters of renal function were determined. Kidney samples were collected for histological studies and generated homogenates for biochemical analysis. In T2DN rats, severe hyperglycemia was developed, FBG were markedly elevated. Diabetes induced significant alterations in renal structure, such as severe reduction of glomerular tufts, increase in Bowman's spaces, thickening of GBM. In addition, and SCr, UAER and BUN are elevated, accompanied with reduction in UCr and CCr, indicating obvious renal failure. On the other hand, endogenous antioxidants SOD, GSH-Px were reduced, whereas MDA was increased. However, treatment of T2DN rats with simvastatin restored renal changes in different aspects. Our results showed that STZ-induced T2DN could be attenuated by simvastatin. The renoprotective effects of simvastatin was indicated by improvements in kidney function parameters, and was attributed by its lipid-lowering effect as well as its anti-oxidative stress, anti-inflammatory properties without having noticeable influence on glycemic control. Simvastatin ameliorates low-dose Streptozotocin-induced type 2 diabetic nephropathy in an experimental rat model. PMID:26131264

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

    PubMed

    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. PMID:24115330

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

    PubMed Central

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

    2014-01-01

    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 (PAMPs) and danger-associated molecular patterns (DAMPS). Experimentally, polymethylmethacrylate (PMMA) 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. PMID:24115330

  6. Experimental characterisation and modelling of deformation- induced microstructure in an A6061 aluminium alloy

    NASA Astrophysics Data System (ADS)

    Kreyca, J. F.; Falahati, A.; Kozeschnik, E.

    2016-03-01

    For industry, the mechanical properties of a material in form of flow curves are essential input data for finite element simulations. Current practice is to obtain flow curves experimentally and to apply fitting procedures to obtain constitutive equations that describe the material response to external loading as a function of temperature and strain rate. Unfortunately, the experimental procedure for characterizing flow curves is complex and expensive, which is why the prediction of flow-curves by computer modelling becomes increasingly important. In the present work, we introduce a state parameter based model that is capable of predicting the flow curves of an A6061 aluminium alloy in different heat-treatment conditions. The model is implemented in the thermo-kinetic software package MatCalc and takes into account precipitation kinetics, subgrain formation, dynamic recovery by spontaneous annihilation and dislocation climb. To validate the simulation results, a series of compression tests is performed on the thermo-mechanical simulator Gleeble 1500.

  7. Histopathological and immunohistochemical study of the hepatic lesions experimentally induced by Entamoeba dispar

    PubMed Central

    Costa, C.A.X.; Brito, K.N.O.; Gomes, M.A.; Caliari, M.V.

    2010-01-01

    The sequence of hepatic necrotic-inflammatory events produced by Entamoeba dispar are originally described in this work. For the first time the experimental lesions produced by E. dispar were described in details, as well as the distribution of the trophozoites detected by the immunohistochemistry. Animals experimentally infected with E. dispar presented necrosis, thrombosis and chronic granulomatous inflammation. Immunoreactive products derived from trofozoites were observed close or associated with trophozoites, epithelioid cells, leucocytes and hepatocytes. Few are the articles on the literature about virulence of E. dispar, which is approximately 9 times more frequent than to Entamoeba histolytica (E. histolytica). Variation in the virulence is therefore expected and signalizing the need of the continuity of studies with E. dispar strains from different places in the world. Taking into account that E. dispar is a closely related species to E. histolytica, these studies could determine new elements involved with E. histolytica pathogenesis, helping us to better understand the disease. PMID:20819776

  8. Experimental procedures to mitigate electron beam induced artifacts during in situ fluid imaging of nanomaterials.

    PubMed

    Woehl, Taylor J; Jungjohann, Katherine L; Evans, James E; Arslan, Ilke; Ristenpart, William D; Browning, Nigel D

    2013-04-01

    Scanning transmission electron microscopy of various fluid and hydrated nanomaterial samples has revealed multiple imaging artifacts and electron beam-fluid interactions. These phenomena include growth of crystals on the fluid stage windows, repulsion of particles from the irradiated area, bubble formation, and the loss of atomic information during prolonged imaging of individual nanoparticles. Here we provide a comprehensive review of these fluid stage artifacts, and we present new experimental evidence that sheds light on their origins in terms of experimental apparatus issues and indirect electron beam sample interactions with the fluid layer. A key finding is that many artifacts are a result of indirect electron beam interactions, such as production of reactive radicals in the water by radiolysis, and the associated crystal growth. The results presented here will provide a methodology for minimizing fluid stage imaging artifacts and acquiring quantitative in situ observations of nanomaterial behavior in a liquid environment.

  9. Determining experimentally induced variation in coniferous canopy chemistry with Airborne Imaging Spectrometer data

    NASA Technical Reports Server (NTRS)

    Swanberg, N. A.; Matson, P. A.

    1989-01-01

    Experimental treatments in a Douglas-fir forest in NE New Mexico were carried out to determine whether differences in forest canopy chemistry could be detected using data from the Airborne Imaging Spectrometer (AIS-2). Experimental treatments consisted of nitrogen fertilizer additions, sawdust additions, and control plots. After AIS-2 data were collected, the digital number of a given pixel was extracted from each channel, yielding 128 values that were used to form a spectrum. Four spectra were extracted from each treatment plot. Multiple stepwise linear regressions between first and second difference transformations of AIS-2 spectra and the canopy characteristics of biomass, nitrogen concentration, and nitrogen content were performed. The results showed a coefficient of multiple determination of 0.71 between first-difference AIS-2 spectra and measured nitrogen concentration in foliage, indicating that it may be possible to predict nitrogen concentration in Douglas fir using AIS-2 spectra.

  10. Experimental investigation on dynamic characteristics and strengthening mechanism of laser-induced cavitation bubbles.

    PubMed

    Ren, X D; He, H; Tong, Y Q; Ren, Y P; Yuan, S Q; Liu, R; Zuo, C Y; Wu, K; Sui, S; Wang, D S

    2016-09-01

    The dynamic features of nanosecond laser-induced cavitation bubbles near the light alloy boundary were investigated with the high-speed photography. The shock-waves and the dynamic characteristics of the cavitation bubbles generated by the laser were detected using the hydrophone. The dynamic features and strengthening mechanism of cavitation bubbles were studied. The strengthening mechanisms of cavitation bubble were discussed when the relative distance parameter γ was within the range of 0.5-2.5. It showed that the strengthening mechanisms caused by liquid jet or shock-waves depended on γ much. The research results provided a new strengthening method based on laser-induced cavitation shotless peening (CSP).

  11. Experimental investigation on dynamic characteristics and strengthening mechanism of laser-induced cavitation bubbles.

    PubMed

    Ren, X D; He, H; Tong, Y Q; Ren, Y P; Yuan, S Q; Liu, R; Zuo, C Y; Wu, K; Sui, S; Wang, D S

    2016-09-01

    The dynamic features of nanosecond laser-induced cavitation bubbles near the light alloy boundary were investigated with the high-speed photography. The shock-waves and the dynamic characteristics of the cavitation bubbles generated by the laser were detected using the hydrophone. The dynamic features and strengthening mechanism of cavitation bubbles were studied. The strengthening mechanisms of cavitation bubble were discussed when the relative distance parameter γ was within the range of 0.5-2.5. It showed that the strengthening mechanisms caused by liquid jet or shock-waves depended on γ much. The research results provided a new strengthening method based on laser-induced cavitation shotless peening (CSP). PMID:27150764

  12. Hybrid predictions of railway induced ground vibration using a combination of experimental measurements and numerical modelling

    NASA Astrophysics Data System (ADS)

    Kuo, K. A.; Verbraken, H.; Degrande, G.; Lombaert, G.

    2016-07-01

    Along with the rapid expansion of urban rail networks comes the need for accurate predictions of railway induced vibration levels at grade and in buildings. Current computational methods for making predictions of railway induced ground vibration rely on simplifying modelling assumptions and require detailed parameter inputs, which lead to high levels of uncertainty. It is possible to mitigate against these issues using a combination of field measurements and state-of-the-art numerical methods, known as a hybrid model. In this paper, two hybrid models are developed, based on the use of separate source and propagation terms that are quantified using in situ measurements or modelling results. These models are implemented using term definitions proposed by the Federal Railroad Administration and assessed using the specific illustration of a surface railway. It is shown that the limitations of numerical and empirical methods can be addressed in a hybrid procedure without compromising prediction accuracy.

  13. Experimental study of induced inflammation in the Brazilian Boa (Boa constrictor constrictor).

    PubMed

    Tucunduva, M; Borelli, P; Silva, J R

    2001-01-01

    The objective of this work was to identify the cellular types present in inflammatory processes in the Brazilian snake, Boa constrictor constrictor. Blood smears were first made from three normal snakes and stained by several methods to identify the cell types present, thus facilitating the identification of cells in inflammatory processes induced in 16 further snakes by the subcutaneous implantation of cotton suture threads and circular coverslips. Implanted threads induced migration of heterophils and monocytes after 4 h, more intense monocyte migration after 24 h, an intense granulocytic migration inside and around the thread after 48 h, heterophilic granulocytes, macrophages and giant cells after 7 days, and giant cells with a typical granuloma response and persistence of heterophilic cells after 15, 69 and 117 days. The cell population attached to the implanted coverslips after 4 h was composed of heterophils, thrombocytes, erythrocytes and macrophages; after 24 and 48 h heterophils predominated, and after 7 days heterophils, macrophages and giant cells predominated.

  14. Experimental study of radiation induced electromotive force effects on mineral insulated cables

    NASA Astrophysics Data System (ADS)

    Van Nieuwenhove, R.; Vermeeren, L.

    2003-11-01

    Measurements of radiation induced electromotive force (RIEMF) effects on mineral insulated cables in a pure gamma field and in a combined neutron and gamma field are presented and compared to model calculations. The effect of materials in the immediate surroundings of the cable, as predicted by the model calculations, is clearly demonstrated. In a fission reactor environment, delayed current contributions due to the neutron activation and subsequent beta emission in base materials as well as in impurities such as Mn are clearly observed and are well reproduced by model calculations. The prediction of the gamma induced current component was severely complicated by its strong sensitivity to the detailed geometry and the spectrum and the directivity of the gamma field. Although the RIEMF effect on MI cables can therefore in general not be completely eliminated, some guidelines are provided to minimize them.

  15. Experimental evidence on removing copper and light-induced degradation from silicon by negative charge

    SciTech Connect

    Boulfrad, Yacine Lindroos, Jeanette; Yli-Koski, Marko; Savin, Hele; Wagner, Matthias; Wolny, Franziska

    2014-11-03

    In addition to boron and oxygen, copper is also known to cause light-induced degradation (LID) in silicon. We have demonstrated previously that LID can be prevented by depositing negative corona charge onto the wafer surfaces. Positively charged interstitial copper ions are proposed to diffuse to the negatively charged surface and consequently empty the bulk of copper. In this study, copper out-diffusion was confirmed by chemical analysis of the near surface region of negatively/positively charged silicon wafer. Furthermore, LID was permanently removed by etching the copper-rich surface layer after negative charge deposition. These results demonstrate that (i) copper can be effectively removed from the bulk by negative charge, (ii) under illumination copper forms a recombination active defect in the bulk of the wafer causing severe light induced degradation.

  16. Influenza A virus-induced polymorphonuclear leukocyte dysfunction in the pathogenesis of experimental pneumococcal otitis media.

    PubMed Central

    Abramson, J S; Giebink, G S; Quie, P G

    1982-01-01

    The role of influenza A virus-induced polymorphonuclear leukocyte and eustachian tube dysfunction in the pathogenesis of acute purulent otitis media was studied in chinchillas. Polymorphonuclear leukocyte function, middle ear pressure, and the incidence of pneumococcal otitis media were observed after intranasal inoculation with influenza A virus, Streptococcus pneumoniae, or both. Results showed that depressed negative middle ear pressure and polymorphonuclear leukocyte chemiluminescence and chemotactic activity occurred after influenza inoculation, but not after inoculation with pneumococcus alone. The greatest incidence of pneumococcal otitis media occurred when the pneumococcus was inoculated just before the time of influenza-induced polymorphonuclear leukocyte dysfunction and negative middle ear pressure. Animals that had unilateral tympanostomy tubes placed before inoculation of influenza with pneumococcus showed no difference in the occurrence of pneumococcal otitis media in ventilated and nonventilated ears, suggesting that polymorphonuclear leukocyte dysfunction contributes more to the pathogenesis of pneumococcal otitis media than does negative middle ear pressure in this animal model. PMID:7076299

  17. Experimental Evaluation of Neutron Induced Noise on Gated X-ray Framing Cameras

    SciTech Connect

    Izumi, N; Stone, G; Hagmann, C; Sorce, C; Bradley, D K; Moran, M; Landen, O L; Stoeffl, W; Springer, P; Tommasini, R; Hermann, H W; Kyrala, G A; Glebov, V Y; Sangster, T C; Koch, J A

    2009-10-08

    A micro-channel plate based temporally-gated x-ray camera (framing camera) is one of the most versatile diagnostic tools of inertial confinement fusion experiments; particularly for observation of the shape of x-ray self emission from compressed core of imploded capsules. However, components used in an x-ray framing camera have sensitivity to neutrons induced secondary radiations. On early low-yield capsule implosions at the National Ignition Facility (NIF), the expected neutron production is about 5 x 10{sup 14}. Therefore, the expected neutron fluence at a framing camera located {approx} 150 cm from the object is 2 x 10{sup 9} neutrons/cm{sup 2}. To obtain gated x-ray images in such harsh neutron environments, quantitative understanding of neutron-induced backgrounds is crucial.

  18. Experimental study on light induced influence model to mice using support vector machine

    NASA Astrophysics Data System (ADS)

    Ji, Lei; Zhao, Zhimin; Yu, Yinshan; Zhu, Xingyue

    2014-08-01

    Previous researchers have made studies on different influences created by light irradiation to animals, including retinal damage, changes of inner index and so on. However, the model of light induced damage to animals using physiological indicators as features in machine learning method is never founded. This study was designed to evaluate the changes in micro vascular diameter, the serum absorption spectrum and the blood flow influenced by light irradiation of different wavelengths, powers and exposure time with support vector machine (SVM). The micro images of the mice auricle were recorded and the vessel diameters were calculated by computer program. The serum absorption spectrums were analyzed. The result shows that training sample rate 20% and 50% have almost the same correct recognition rate. Better performance and accuracy was achieved by third-order polynomial kernel SVM quadratic optimization method and it worked suitably for predicting the light induced damage to organisms.

  19. Natural breeding with bulls experimentally infected with Neospora caninum failed to induce seroconversion in dams.

    PubMed

    Osoro, K; Ortega-Mora, L M; Martínez, A; Serrano-Martínez, E; Ferre, I

    2009-03-01

    Four bulls and 56 heifers seronegative to Neospora caninum were used to determine the feasibility of venereal transmission in bovine neosporosis under natural conditions. Bulls were experimentally infected with 10(8) live N. caninum tachyzoites. Two of them with the Nc-1 isolate and the other two with the Nc-Spain-7 isolate. After 13 months of initial infection, each bull was re-infected with the same isolate and dose. The experiments were carried out from March to September during 2006 and 2007 where groups of cyclic heifers were naturally mated by the experimentally infected bulls. In year 2006, two bulls infected with different N. caninum isolate serviced 12 heifers each. In year 2007, the same bulls serviced the same heifers a second time (now primiparous) and six new heifers were also added to each group. In addition, the other two bulls serviced 10 additional heifers each. Experimental animals were monitored for 30 weeks and serum samples were collected weekly and fortnightly in years 2006 and 2007, respectively to evaluate the presence of specific antibodies to N. caninum. Experimentally infected bulls showed a significant increase of specific IgG antibodies from 13 (Nc-SP-7) and 21 (Nc-1) days post-infection. Serum IgG antibody responses of individual animals were similar in kinetics but slightly different in magnitude. Serum samples from heifers were all negative. Pregnant rates were 100% in heifers and 91% in primiparous animals. Calves did not show precolostral specific antibodies to N. caninum. Venereal transmission of bovine neosporosis under natural grazing conditions is unlikely to occur.

  20. Experimental investigation of lateral forces induced by flow through model labyrinth glands

    NASA Technical Reports Server (NTRS)

    Leong, Y. M. M. S.; Brown, R. D.

    1984-01-01

    The lateral forces induced by flow through model labyrinth glands were investigated. Circumferential pressure distributions, lateral forces and stiffness coefficients data obtained are discussed. The force system is represented as a negative spring and a tangential force orthogonal to eccentricity. The magnitude of these forces are dependent on eccentricity, entry swirl, rotor peripheral velocity and seal size. A pressure equalization chamber at midgland tests should in significantly reduced forces and stiffness coefficients.

  1. Solute induced relaxation in glassy polymers: Experimental measurements and nonequilibrium thermodynamic model

    SciTech Connect

    Minelli, Matteo; Doghieri, Ferruccio

    2014-05-15

    Data for kinetics of mass uptake from vapor sorption experiments in thin glassy polymer samples are here interpreted in terms of relaxation times for volume dilation. To this result, both models from non-equilibrium thermodynamics and from mechanics of volume relaxation contribute. Different kind of sorption experiments have been considered in order to facilitate the direct comparison between kinetics of solute induced volume dilation and corresponding data from process driven by pressure or temperature jumps.

  2. Effect of Scutellariae Radix extract on experimental dextran-sulfate sodium-induced colitis in rats

    PubMed Central

    Chung, Ho-Lam; Yue, Grace Gar-Lee; To, Ka-Fai; Su, Ya-Lun; Huang, Yu; Ko, Wing-Hung

    2007-01-01

    AIM: To investigate the effect of Scutellariae Radix extract (SRE) on ulcerative colitis (UC) in rats induced by dextran-sulfate sodium (DSS). METHODS: Colitis was induced in male Sprague-Dawley (SD) rats (170-180 g) by 4% dextran sulfate sodium (DSS, wt/v; MW 54000) in drinking water for 8 d. The treated rats received 4% DSS and SRE orally (100 mg/kg per day). Control rats received either tap water or SRE only. Macroscopic assessment which included body weight changes, fecal occult blood and stool consistency were determined daily. At the appointed time, the rats were sacrificed and the entire colons were removed. The colon length and the myeloperoxidase (MPO) activity were measured. The severity of colitis was graded by morphological and histological assessments. The ion transport activity of the colonic mucosa was assessed by electrophysiological technique. RESULTS: Rats treated with oral administration of 4% DSS regularly developed clinical and macroscopic signs of colitis. Treatment with SRE relieved the symptoms, including the reduction in body weight, shortening and ulceration of the colon. Administration of SRE also significantly reduced the histological damage induced by DSS. Moreover, the ISC responses of the colonic mucosa to forskolin were suppressed after the induction of colitis. The stimulated ion transport activity of DSS-rats treated with SRE displayed significant improvement in the secretory responsiveness. CONCLUSION: SRE was effective in treating acute DSS-induced ulcerative colitis, as gauged by reduced clinical disease, improved macroscopic and histological damage scores, and enhanced recovery of normal colonic secretory function. PMID:17948935

  3. Experimental investigation on the flow-induced noise under variable conditions for centrifugal pumps

    NASA Astrophysics Data System (ADS)

    Yuan, Shouqi; Yang, Jun; Yuan, Jianping; Luo, Yin; Pei, Ji

    2012-05-01

    With extensively using of centrifugal pumps, noise generation in these pumps is increasingly receiving research attention in recent years. The noise sources in centrifugal pumps are mainly composed of mechanical noise and flow-induced noise. And the study of flow-induced noise has become a hotspot and important domain in the field. The flow-induced noise closely related to the inner pressure pulses and vibration of volute in pumps, therefore, it is necessary to research the interaction and mechanism among them. To investigate the relationships, a test system is designed which includes a test loop and a measurement system. The hydrophones and pressure sensors are installed on the outlet of the pump and vibration acceleration sensors are disposed on the pump body. Via these instruments, the signals of noise, pressure pulses and vibration are collected and analyzed. The results show that the level of flow-induced noise becomes smaller as the flow increment during low flow rate operations, and it is steadily close to the design point, then it increases with the growing of flow rate in high flow rate conditions. Furthermore, there are some similar peak points in the power spectrum charts of noise, pressure pulses and vibration. The broadband noise at low flow rate is mostly focused on the region of 0-40 times shaft frequency, which is mostly made by rotating stall and vortex; while the noise at high flow rate conditions is focused on the region of 60-100 times shaft frequency, which may be mostly made by cavitations. The proposed research is of practical and academic significance to the study of noise reduction for centrifugal pumps.

  4. Fractal Dimension in Quantifying Experimental-Pulmonary-Hypertension-Induced Cardiac Dysfunction in Rats

    PubMed Central

    Pacagnelli, Francis Lopes; Sabela, Ana Karênina Dias de Almeida; Mariano, Thaoan Bruno; Ozaki, Guilherme Akio Tamura; Castoldi, Robson Chacon; do Carmo, Edna Maria; Carvalho, Robson Francisco; Tomasi, Loreta Casquel; Okoshi, Katashi; Vanderlei, Luiz Carlos Marques

    2016-01-01

    Background Right-sided heart failure has high morbidity and mortality, and may be caused by pulmonary arterial hypertension. Fractal dimension is a differentiated and innovative method used in histological evaluations that allows the characterization of irregular and complex structures and the quantification of structural tissue changes. Objective To assess the use of fractal dimension in cardiomyocytes of rats with monocrotaline-induced pulmonary arterial hypertension, in addition to providing histological and functional analysis. Methods Male Wistar rats were divided into 2 groups: control (C; n = 8) and monocrotaline-induced pulmonary arterial hypertension (M; n = 8). Five weeks after pulmonary arterial hypertension induction with monocrotaline, echocardiography was performed and the animals were euthanized. The heart was dissected, the ventricles weighed to assess anatomical parameters, and histological slides were prepared and stained with hematoxylin/eosin for fractal dimension analysis, performed using box-counting method. Data normality was tested (Shapiro-Wilk test), and the groups were compared with non-paired Student t test or Mann Whitney test (p < 0.05). Results Higher fractal dimension values were observed in group M as compared to group C (1.39 ± 0.05 vs. 1.37 ± 0.04; p < 0.05). Echocardiography showed lower pulmonary artery flow velocity, pulmonary acceleration time and ejection time values in group M, suggesting function worsening in those animals. Conclusion The changes observed confirm pulmonary-arterial-hypertension-induced cardiac dysfunction, and point to fractal dimension as an effective method to evaluate cardiac morphological changes induced by ventricular dysfunction. PMID:27223643

  5. Temperature-induced shifts in hibernation behavior in experimental amphibian populations.

    PubMed

    Gao, Xu; Jin, Changnan; Llusia, Diego; Li, Yiming

    2015-06-23

    Phenological shifts are primary responses of species to recent climate change. Such changes might lead to temporal mismatches in food webs and exacerbate species vulnerability. Yet insights into this phenomenon through experimental approaches are still scarce, especially in amphibians, which are particularly sensitive to changing thermal environments. Here, under controlled warming conditions, we report a critical, but poorly studied, life-cycle stage (i.e., hibernation) in frogs inhabiting subtropical latitudes. Using outdoor mesocosm experiments, we examined the effects of temperature (ambient vs. + ~2.2/2.4 °C of pre-/post-hibernation warming) and food availability (normal vs. 1/3 food) on the date of entrance into/emergence from hibernation in Pelophylax nigromaculatus. We found temperature was the major factor determining the hibernation period, which showed a significant shortening under experimental warming (6-8 days), with delays in autumn and advances in spring. Moreover, the timing of hibernation was not affected by food availability, whereas sex and, particularly, age were key factors in the species' phenological responses. Specifically, male individuals emerged from hibernation earlier, while older individuals also entered and emerged from hibernation earlier. We believe that this study provides some of the first experimental evidence for the effect of climate warming on the timing of amphibian hibernation.

  6. Temperature-induced shifts in hibernation behavior in experimental amphibian populations

    PubMed Central

    Gao, Xu; Jin, Changnan; Llusia, Diego; Li, Yiming

    2015-01-01

    Phenological shifts are primary responses of species to recent climate change. Such changes might lead to temporal mismatches in food webs and exacerbate species vulnerability. Yet insights into this phenomenon through experimental approaches are still scarce, especially in amphibians, which are particularly sensitive to changing thermal environments. Here, under controlled warming conditions, we report a critical, but poorly studied, life-cycle stage (i.e., hibernation) in frogs inhabiting subtropical latitudes. Using outdoor mesocosm experiments, we examined the effects of temperature (ambient vs. + ~2.2/2.4 °C of pre-/post-hibernation warming) and food availability (normal vs. 1/3 food) on the date of entrance into/emergence from hibernation in Pelophylax nigromaculatus. We found temperature was the major factor determining the hibernation period, which showed a significant shortening under experimental warming (6–8 days), with delays in autumn and advances in spring. Moreover, the timing of hibernation was not affected by food availability, whereas sex and, particularly, age were key factors in the species’ phenological responses. Specifically, male individuals emerged from hibernation earlier, while older individuals also entered and emerged from hibernation earlier. We believe that this study provides some of the first experimental evidence for the effect of climate warming on the timing of amphibian hibernation. PMID:26100247

  7. Temperature-induced shifts in hibernation behavior in experimental amphibian populations.

    PubMed

    Gao, Xu; Jin, Changnan; Llusia, Diego; Li, Yiming

    2015-01-01

    Phenological shifts are primary responses of species to recent climate change. Such changes might lead to temporal mismatches in food webs and exacerbate species vulnerability. Yet insights into this phenomenon through experimental approaches are still scarce, especially in amphibians, which are particularly sensitive to changing thermal environments. Here, under controlled warming conditions, we report a critical, but poorly studied, life-cycle stage (i.e., hibernation) in frogs inhabiting subtropical latitudes. Using outdoor mesocosm experiments, we examined the effects of temperature (ambient vs. + ~2.2/2.4 °C of pre-/post-hibernation warming) and food availability (normal vs. 1/3 food) on the date of entrance into/emergence from hibernation in Pelophylax nigromaculatus. We found temperature was the major factor determining the hibernation period, which showed a significant shortening under experimental warming (6-8 days), with delays in autumn and advances in spring. Moreover, the timing of hibernation was not affected by food availability, whereas sex and, particularly, age were key factors in the species' phenological responses. Specifically, male individuals emerged from hibernation earlier, while older individuals also entered and emerged from hibernation earlier. We believe that this study provides some of the first experimental evidence for the effect of climate warming on the timing of amphibian hibernation. PMID:26100247

  8. SPATIAL MEMORY IMPAIRMENT AND HIPPOCAMPAL CELL LOSS INDUCED BY OKADAIC ACID (EXPERIMENTAL STUDY).

    PubMed

    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.

  9. Experimental determination of the relationship between permeability and microfracture-induced damage in bedded salt

    SciTech Connect

    Pfeifle, T.W.

    1998-03-01

    The development of deep underground structures (e.g., shafts, mines, storage and disposal caverns) significantly alters the stress state in the rock near the structure or opening. The effect of such an opening is to concentrate the far-field stress near the free surface. For soft rock such as salt, the concentrating effect of the opening induces deviatoric stresses in the salt that may be large enough to initiate microcracks which then propagate with time. The volume of rock susceptible to damage by microfracturing is often referred to as the disturbed rock zone and, by its nature, is expected to exhibit high permeability relative to that of the native, far-field rock. This paper presents laboratory data that characterize microfracture-induced damage and the effect this damage has on permeability for bedded salt from the Waste Isolation Pilot Plant located in southeastern New Mexico. Damage is induced in the salt through a series of tertiary creep experiments and quantified in terms of dilatant volumetric strain. The permeability of damaged specimens is then measured using nitrogen gas as the permeant. The range in damage investigated included dilatant volumetric strains from less than 0.03 percent to nearly 4.0 percent. Permeability values corresponding to these damage levels ranged from 1 {times} 10{sup {minus}18} m{sup 2} to 1 {times} 10{sup {minus}12} m{sup 2}. Two simple models were fitted to the data for use in predicting permeability from dilatant volumetric strain.

  10. Cognitive performance and convulsion risk after experimentally-induced febrile-seizures in rat.

    PubMed

    Rajab, Ebrahim; Abdeen, Zahra; Hassan, Zuhair; Alsaffar, Yousif; Mandeel, Mohammad; Al Shawaaf, Fatima; Al-Ansari, Sali; Kamal, Amer

    2014-05-01

    Many reports indicated that small percentage of children with febrile seizures develop epilepsy and cognitive disorders later in adulthood. In addition, the neuronal network of the hippocampus was reported to be deranged in adult animals after being exposed to hyperthermia-induced seizures in their neonatal life. The aims of this study were to investigate (1) latency and probability of seizures, (2) spatial learning and memory, in adult rats after neonatal hyperthermia-induced febrile seizures (FS). Prolonged FS were elicited in 10-day old, male Sprague Dawleys (n=11/group) by exposure to heated air (48-52 °C) for 30 min; control rats were exposed to 30 °C air. After 1.5 months the animal's cognitive performance was assessed by 5 day trial in the Morris water maze. In another experiment the latency and probability of seizures were measured in response to pentylenetetrazole (PTZ) injections (increased doses ranged from 7 to 140 mg/kg; i.p.). In water maze, both groups showed improvements in escape latency and distance swam to reach the platform; effects were significantly greater in control versus hyperthermia-treated animals on days 3 and 4. Latency and probability of PTZ-induced seizures were shorter and higher respectively, in hyperthermia-treated animals compared to controls. We concluded that FS in neonatal rats leads to enhanced susceptibility for seizures, as well as cognitive deficits in adults.

  11. 3D experimental investigation of the interplay between dielectrophoresis and induced-charge electroosmosis

    NASA Astrophysics Data System (ADS)

    Boymelgreen, Alicia; Zehavi, Matan; Yossifon, Gilad

    2014-11-01

    It is well-known that the advent non-linear electrokinetic flows, such as induced-charge electroosmosis, are strongly dependent on the frequency of the applied field. However, to date, there exists no unifying theory which can exactly predict both the strength and frequency dispersion of such electrokinetic flows. Using microPIV and temperature sensitive dyes we demonstrate the presence of a number of competing non-linear effects including dielectrophoresis, electrothermal flow and wall effects which compete with induced-charge electrokinetic flow, potentially causing a distortion of both the strength and frequency dispersion predicted for pure induced-charge effects. In terms of the wall effects, we investigate the differences between channels in which the walls are conducting (the field is perpendicular to the wall) and insulating (the field is parallel to the wall). This work is of both fundamental and practical importance and may be used to further refine non-linear electrokinetic theory and optimize the flow parameters of electroosmotic pumps and the mobility of electrokinetically driven micromotors or carriers in lab-on-a-chip analysis systems.

  12. Evaluation of the antipsychotic potential of Panax quinquefolium in ketamine induced experimental psychosis model in mice.

    PubMed

    Chatterjee, Manavi; Singh, Seema; Kumari, Reena; Verma, Anil Kumar; Palit, Gautam

    2012-04-01

    The search for novel pharmacotherapy from medicinal plants for psychiatric illnesses has progressed significantly from the past few decades and their therapeutic potential has been assessed in a variety of animal models. The aim of our study was to screen one such plant, Panax quinquefolium (PQ), with significant neuroactive properties for its antipsychotic potential. A graded dose study with PQ at 12.5-200 mg/kg, p. o. showed differential effects against the ketamine induced hyperactivity in the Digiscan animal activity monitor. Nevertheless at 100 mg/kg, p.o., PQ blocked ketamine induced memory impairment in the passive avoidance paradigm. In the chronic studies, PQ reduced the ketamine induced enhanced immobility in the forced swim test and did not show extra-pyramidal side effects in bar test and wood block test of catalepsy. These behavioural effects were compared with standard drugs haloperidol and clozapine. Further PQ reduced DA and 5-HT content after chronic treatment, but not after acute administration. In addition, PQ extract reduced acetylcholinesterase activity and nitrate levels, however increased glutamate levels in hippocampus. Overall our findings suggest that PQ possess antipsychotic like properties, which may leads to future studies with its specific constituents which may particularly be beneficial in predominant negative and cognitive symptoms of schizophrenia. PMID:22189635

  13. Degree of Immunity Induced by Killed Vaccines to Experimental Salmonellosis in Mice

    PubMed Central

    Herzberg, Mendel; Nash, Peter; Hino, Sharon

    1972-01-01

    Killed vaccines, deoxycholate-extracted or heated, were shown to induce an effective degree of immunity which protected against death (100%), prevented extensive multiplication, and left the mice with low residual salmonella populations in spleen and liver after intravenous (iv) or intraperitoneal (ip) challenge with virulent Salmonella typhimurium. Protection was most effective against the ip challenge route and less effective against the iv route. A study of the kinetics of the population of bacteria in the spleens and livers of immunized animals showed that after ip challenge there was an initial reduction of 99% at 6 hr after challenge, maintenance of levels of less than 103 bacteria per organ, and a final population of 102 to 103 per organ at 21 days. With iv challenge, after an initial reduction of 90% at 6 hr, growth ensued to levels above 106 bacteria per organ until 8 days, followed by a steady decline yielding residual populations of 103 to 104 in some cases. Organ hypertrophy correlated with bacterial population. Morbidity was prevented (as measured by gain in body weight) by immunization against ip challenge but not against iv challenge. Killed vaccines protected by their ability to induce an immune state which reduced the initial challenge population, prevented extensive multiplication, yet allowed “cellular immunity” to develop due to response to the living challenge infection itself. The consequence was a low-level carrier state similar to that induced by recovery from sublethal virulent infection. PMID:4570987

  14. Experimental Advances Towards Neural Regeneration from Induced Stem Cells to Direct In Vivo Reprogramming.

    PubMed

    Dametti, Sara; Faravelli, Irene; Ruggieri, Margherita; Ramirez, Agnese; Nizzardo, Monica; Corti, Stefania

    2016-05-01

    Neuronal loss is a common substrate of many neurological diseases that still lack effective treatments and highly burden lives of affected individuals. The discovery of self-renewing stem cells within the central nervous system (CNS) has opened the doors to the possibility of using the plasticity of CNS as a potential strategy for the development of regenerative therapies after injuries. The role of neural progenitor cells appears to be crucial, but insufficient in reparative processes after damage. In addition, the mechanisms that regulate these events are still largely unknown. Stem cell-based therapeutic approaches have primarily focused on the use of either induced pluripotent stem cells or induced neural stem cells as sources for cell transplantation. More recently, in vivo direct reprogramming of endogenous CNS cells into multipotent neural stem/progenitor cells has been proposed as an alternative strategy that could overcome the limits connected with both the invasiveness of exogenous cell transplantation and the technical issues of in vitro reprogramming (i.e., the time requested and the limited available amount of directly induced neuronal cells). In this review, we aim to highlight the recent studies on in vivo direct reprogramming, focusing on astrocytes conversion to neurons or to neural stem/precursors cells, in the perspective of future therapeutic purposes for neurological disorders.

  15. Cardiovascular effects of black tea and nicotine alone or in combination against experimental induced heart injury.

    PubMed

    Joukar, Siyavash; Bashiri, Hamideh; Dabiri, Shahriar; Ghotbi, Payam; Sarveazad, Arash; Divsalar, Kouros; Joukar, Farzin; Abbaszadeh, Mahsa

    2012-06-01

    The present study was designed to elucidate the outcome of subchronic co-administration of black tea and nicotine on cardiovascular performance and whether these substances could modulate the isoproterenol-induced cardiac injury. Animal groups were control, black tea, nicotine and black tea plus nicotine. Test groups received nicotine (2 mg/kg s.c.) and black tea brewed (p.o.) each alone and in combination for 4 weeks. On the 28th day, myocardial damage was induced by isoproterenol (50 mg/kg i.p.), and blood samples were taken. On day 29, after hemodynamic parameters recording, hearts were removed for histopathological evaluation. Tea or nicotine consumption had no significant effects on hemodynamic indices of animals without heart damage. When the cardiac injury was induced, tea consumption maintained the maximum dp/dt, and nicotine significantly decreased the pressure-rate product. Moreover, severity of heart lesions was lower in the presence of nicotine or black tea. Concomitant use of these materials did not show extra effects on mentioned parameters more than the effect of each of them alone. The results suggest that subchronic administration of black tea or nicotine for a period of 4 weeks may have a mild cardioprotective effect, while concomitant use of these materials cannot intensify this beneficial effect.

  16. Cholecystokinin-induced anxiety in rats: relevance of pre-experimental stress and seasonal variations.

    PubMed Central

    Kõks, S; Männistö, P T; Bourin, M; Shlik, J; Vasar, V; Vasar, E

    2000-01-01

    OBJECTIVE: To examine the influence of pre-experimental stress on the anxiogenic-like action of caerulein, an agonist of cholecystokinin (CCK) receptors. Differences in the anxiety levels of rats in summer and winter, and the role of CCK in these behavioural alterations, were also examined. DESIGN: Prospective animal study. INTERVENTIONS: Male Wistar rats were injected with the CCK agonist caerulein, or the CCK antagonists L-365,260 or devazepide, after being exposed to pre-experimental stress (handling and isolation). OUTCOME MEASURES: Performance in the plus-maze model of anxiety; serum levels of prolactin, thyrotropin and growth hormone; brain density and affinity of dopamine D2, serotonin 5-HT2 and CCK receptors. RESULTS: Caerulein (5 micrograms/kg, subcutaneous injection) caused the strongest action in animals brought to the experimental room immediately before the experiment and kept in isolation after the administration of caerulein. Caerulein did not cause any reduction of exploratory activity in rats made familiar with the experimental room and kept in the home-cage after the injection of the CCK agonist. The anti-exploratory action of caerulein in stressed rats was reversed by the CCK antagonist L-365,260 (100 micrograms/kg, intraperitoneal injection), demonstrating the involvement of the CCKB receptor subtype. In addition, seasonal fluctuations occur in the exploratory activity of rats; such activity was much lower in July than in November. The rats displaying the reduced exploratory activity had an increased number of CCK receptors in the frontal cortex and hippocampus. Simultaneously, the density of serotonin 5-HT2 receptors in the frontal cortex, but not that of dopamine D2 receptors in the striatum, was elevated. The blood level of growth hormone was also higher in July. CONCLUSIONS: The anti-exploratory action of caerulein appears to be dependent on the pre-experimental stress of rats. Moreover, the seasonal variations of exploratory behaviour of

  17. Ruptured giant mitral valve aneurysm: an unexpected finding in a diabetic patient with dyspnea and new-onset atrial fibrillation.

    PubMed

    Trifunovic, Danijela; Vujisic-Tesic, Bosiljka; Bozic, Vesna; Petrovic, Milan; Ostojic, Miodrag

    2014-07-01

    Mitral valve aneurysm (MVA) is a rare valve disease. The case is reported of pathologically proven MVA in a 61-year-old diabetic male with chronic alcoholic liver disease who presented with dyspnea and new-onset atrial fibrillation, without clinical elements of current or recent infection. Transthoracic echocardiography revealed a 'cystic' formation of the anterior mitral leaflet (AML) with mild mitral regurgitation (MR) and aortic regurgitation (AR) hitting the AML. Transesophageal echocardiography (TEE) showed clearly that the formation on the AML was a valve aneurysm, and depicted the site of aneurysm rupture with an additional jet of MR through the rupture. Following mitral valve replacement, pathology of the excised valve showed chronic bacterial endocarditis with calcified bacterial colonies, myxomatous changes with fibrinoid dissection of lamina fibrosa, and neovascularization of the leaflet. The mechanisms of MVA formation are discussed, together with its potential complications, diagnostic modalities and therapeutic strategies. The present case emphasizes that MVA is often a remnant of endocarditis, even when the latter is clinically silent and undiagnosed. The importance of chronic AR directed towards the AML as a predisposing condition for MVA formation is also underlined in this case. The superiority of TEE in providing a full exploration of the mitral valve morphology is verified. PMID:25803977

  18. An 80-Year-Old Man With Dyspnea and Bilateral Pleural Effusions After Partial Nephrectomy for Renal Cell Carcinoma.

    PubMed

    Gupta, Anupam; Farokhi, Mahsan; Shah, Sapna; McGarry, Terence; Warshawsky, Martin; Epelbaum, Oleg

    2016-05-01

    An 80-year-old man presented because of superficial head trauma sustained after falling from bed. On review of systems, he reported worsening dyspnea on exertion, nonproductive cough, and weight loss over the preceding 2 to 3 months. There was no report of chest pain or leg swelling. He had a past medical history of hypertension, coronary artery disease, subclinical hypothyroidism, and renal cell carcinoma treated with partial right nephrectomy approximately 1 year before this presentation. Two months earlier he had been evaluated in the dermatology clinic for painful, dystrophic fingernails. At that time he was diagnosed with acropachy with onycholysis and suspected superinfection, and after failing to improve with vinegar soaks and topical antimicrobials, he underwent surgical nail removal on the second and fourth digits of the right hand. Histological examination of the operative specimens revealed dystrophic nails with negative fungal stains. His medications included levothyroxine, hydrochlorothiazide, and clopidogrel. He had never smoked and had done clerical work until retirement. He was originally from Colombia. PMID:27157230

  19. Experimentally induced innovations lead to persistent culture via conformity in wild birds.

    PubMed

    Aplin, Lucy M; Farine, Damien R; Morand-Ferron, Julie; Cockburn, Andrew; Thornton, Alex; Sheldon, Ben C

    2015-02-26

    In human societies, cultural norms arise when behaviours are transmitted through social networks via high-fidelity social learning. However, a paucity of experimental studies has meant that there is no comparable understanding of the process by which socially transmitted behaviours might spread and persist in animal populations. Here we show experimental evidence of the establishment of foraging traditions in a wild bird population. We introduced alternative novel foraging techniques into replicated wild sub-populations of great tits (Parus major) and used automated tracking to map the diffusion, establishment and long-term persistence of the seeded innovations. Furthermore, we used social network analysis to examine the social factors that influenced diffusion dynamics. From only two trained birds in each sub-population, the information spread rapidly through social network ties, to reach an average of 75% of individuals, with a total of 414 knowledgeable individuals performing 57,909 solutions over all replicates. The sub-populations were heavily biased towards using the technique that was originally introduced, resulting in established local traditions that were stable over two generations, despite a high population turnover. Finally, we demonstrate a strong effect of social conformity, with individuals disproportionately adopting the most frequent local variant when first acquiring an innovation, and continuing to favour social information over personal information. Cultural conformity is thought to be a key factor in the evolution of complex culture in humans. In providing the first experimental demonstration of conformity in a wild non-primate, and of cultural norms in foraging techniques in any wild animal, our results suggest a much broader taxonomic occurrence of such an apparently complex cultural behaviour.

  20. Experimental studies in magnetically induced transverse force-frequency effect in thin quartz microresonators

    SciTech Connect

    Hatipoglu, Gokhan; Tadigadapa, Srinivas

    2015-07-21

    In this work, the transverse force-frequency sensitivity of magnetostrictive Metglas{sup ®} (Fe{sub 85}B{sub 5}Si{sub 10}) thin film coated AT-cut thickness shear mode quartz thin plate microresonator (500 μm × 500 μm × 19 μm) is experimentally measured and modeled in Lagrangian formulation by coupling magnetostrictive deformation equations with the basic plate equations from the theory of small deformation. The quartz plate resonator is fabricated by micromachining techniques and released into fixed-free structure using focused ion beam milling. Application of a magnetic field results in the out-of-plane bending of the structure due to elastic coupling between the magnetostrictive Metglas{sup ®} and quartz resonator layers. As a result of the transverse loading and out-of-plane bending, the admittance characteristics of the resonator shifts, and these shifts are recorded in real time utilizing a network analyzer. The sensitivity is experimentally measured to be 162.3 mdeg/Oe for phase, corresponding to a frequency sensitivity of Δf/H = 11 Hz/Oe. The equivalent force-frequency sensitivity can then be calculated as 2.36 μN/Hz using the developed model. The coupled domain analysis fits well with the experimental data. Further reduction of quartz thickness and optimization of the thickness ratio of the magnetostrictive to quartz layers offers the possibility of exploiting the stress sensitivity of plate microresonators as sensitive magnetic field sensors capable of low nanoTesla to picoTesla level magnetic flux densities.

  1. Experimental determination of the light-trapping-induced absorption enhancement factor in DSSC photoanodes.

    PubMed

    Gagliardi, Serena; Falconieri, Mauro

    2015-01-01

    For dye-sensitized solar cells (DSSC), the fundamental process that determines the maximum short-circuit current is the absorption of light. In such devices, this is produced by the concurrent phenomena of light absorption by dye molecules and light trapping in the mesoporous, titania photoanode structure. The decoupling of these two phenomena is important for device characterization and the design of novel photoelectrode geometries with increased optical performance. In this paper, this task is addressed by introducing a spectral absorption enhancement factor as a parameter to quantify the light trapping effect. The experimental value of this parameter was obtained by comparing the experimentally determined fraction of absorbed light by a dye-sensitized photoanode with the light absorbed by the dye without the mesoporous titania structure. In order to gain more insight from this result, the fraction of light absorbed in the photoanode (on the basis of the dye loading capacity of the titania nanospheres) was also calculated by an optical model for the two extreme cases of the absence of light trapping and maximum light trapping. Accordingly, the photocurrent was calculated under the assumption of solar irradiation, which defined two useful boundaries. Using the experimentally derived values of the spectral absorption enhancement factor in the photoanode optical model, the DSSC short-circuit current can be calculated with good agreement with the value measured in practical devices based on the same photoanode structures. Therefore, our approach provides a realistic description of a practical device and can be exploited as an useful tool to assess the optical functionality of novel photoanode structures.

  2. Effect of Experimentally Induced Hepatic and Renal Failure on the Pharmacokinetics of Topiramate in Rats

    PubMed Central

    Matar, Kamal M.; Tayem, Yasin I.

    2014-01-01

    We aimed to investigate the effect of induced hepatic and renal failure on the pharmacokinetics of topiramate (TPM) in rats. Twenty-four Sprague-Dawley rats were used in this study. Renal or hepatic failure was induced by a single i.p. dose of 7.5 mg/kg cisplatin (n = 8) or 0.5 mL/kg carbon tetrachloride (CCl4) (n = 8), respectively. Three days after cisplatin dose or 24 h after CCl4 dose, the rats were administered a single oral dose of 20 mg/kg TPM. The plasma samples were quantified by LC-MS/MS method. Compared to control, plasma concentration-time profile in CCl4-treated and, to a lesser extent, in cisplatin-treated rats decreased more slowly particularly in the elimination phase. TPM oral clearance (CL/F) in CCl4-treated group was significantly lower than that in control (P < 0.001), whereas AUC0−∞, T1/2, and Vd/F were significantly higher in CCl4-treated rats compared to the control (P < 0.01). The CL/F was not significantly different between cisplatin-treated rats and control (P > 0.05). However, in cisplatin-treated rats, the T1/2 and Vd/F were significantly higher than that in the control group (P < 0.01). Both conditions failed to cause a significant effect on Cmax or Tmax. The present findings suggest that induced hepatic or renal failure could modify the pharmacokinetic profile of TPM in the rat. PMID:25009818

  3. Preventive activity of banana peel polyphenols on CCl4-induced experimental hepatic injury in Kunming mice

    PubMed Central

    WANG, RUI; FENG, XIA; ZHU, KAI; ZHAO, XIN; SUO, HUAYI

    2016-01-01

    The aim of the present study was to evaluate the preventive effects of banana peel polyphenols (BPPs) against hepatic injury. Mice were divide into normal, control, 100 mg/kg and 200 mg/kg banana peel polyphenol and silymarin groups. All the mice except normal mice were induced with hepatic damage using CCl4. The serum and tissue levels of mice were determined by a kit and the tissues were further examined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. BPPs reduced the serum levels of aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase in a CCl4-induced mouse model of hepatic injury. Furthermore, BPPs reduced the levels of malondialdehyde and triglyceride, while increasing glutathione levels in the serum and liver tissues of mice. In addition, the effects of 200 mg/kg treatment were more evident, and these effects were comparable to those of the drug silymarin. Serum levels of the cytokines, interleukin (IL)-6, IL-12, tumor necrosis factor (TNF)-α and interferon-γ, were reduced in the mice treated with BPPs compared with injury control group mice, and these levels were comparable to those of the normal and silymarin-treated groups. Histopathological examination indicated that BPPs were able to reduce the extent of CCl4-induced liver tissue injury and protect the liver cells. Furthermore, the mRNA and protein expression levels of the inflammation-associated factors cyclooxygenase-2, nitric oxide synthase, TNF-α and IL-1β were reduced in mice treated with BPPs compared with the control group mice. Mice that received 200 mg/kg BPP exhibited reduced expression levels of these factors compared with mice that received 100 mg/kg BPP. In conclusion, the results of the present study suggested that BPPs exert a good preventive effect against hepatic injury. PMID:27168833

  4. IGF-1R contributes to stress-induced hepatocellular damage in experimental cholestasis.

    PubMed

    Cadoret, Axelle; Rey, Colette; Wendum, Dominique; Elriz, Khaldoun; Tronche, François; Holzenberger, Martin; Housset, Chantal

    2009-08-01

    The insulin-like growth factor type 1 receptor (IGF-1R) controls aging and cellular stress, both of which play major roles in liver disease. Stimulation of insulin-like growth factor signaling can generate cell death in vitro. Here, we tested whether IGF-1R contributes to stress insult in the liver. Cholestatic liver injury was induced by bile duct ligation in control and liver-specific IGF-1R knockout (LIGFREKO) mice. LIGFREKO mice displayed less bile duct ligation-induced hepatocyte damage than controls, while no differences in bile acid serum levels or better adaptation to cholestasis by efflux transporters were found. We therefore tested whether stress pathways contributed to this phenomenon; oxidative stress, ascertained by both malondialdehyde content and heme oxygenase-1 expression, was similar in knockout and control animals. However, together with a lower level of eukaryotic initiation factor-2 alpha phosphorylation, the endoplasmic reticulum stress protein CHOP and its downstream pro-apoptotic target Bax were induced to lesser extents in LIGFREKO mice than in controls. Expression levels of cytokeratin 19, transforming growth factor-beta1, alpha-smooth muscle actin, and collagen alpha1(I) in LIGFREKO mice were all lower than in controls, indicating reduced ductular and fibrogenic responses and increased cholestasis tolerance in these mutants. This stress resistance phenotype was also evidenced by longer post-bile duct ligation survival in mutants than controls. These results indicate that IGF-1R contributes to cholestatic liver injury, and suggests the involvement of both CHOP and Bax in this process. PMID:19628767

  5. Preventive effects of lignan extract from flax hulls on experimentally induced benign prostate hyperplasia.

    PubMed

    Bisson, Jean-François; Hidalgo, Sophie; Simons, Rudy; Verbruggen, Marian

    2014-06-01

    Consumption of diet rich in lignans may decrease the risk of some chronic hormonal conditions such as benign prostatic hyperplasia (BPH). This study investigated whether a lignan-rich extract from flaxseed hulls, LinumLife EXTRA (LLE), could prevent BPH using the testosterone propionate (TP)-induced BPH rat model. Male Wistar-Unilever rats were randomly divided into four groups of 12 rats each: a negative control group fed with control diet and receiving daily subcutaneous injections of corn oil without TP, and three groups fed with control diet (positive control), diet containing 0.5% LLE (LLE 0.5) or 1.0% LLE (LLE 1.0) and receiving daily subcutaneous injections of TP in corn oil. Treatments with diets started 2 weeks before the induction of BPH and were carried out for 5 consecutive weeks. The influence of TP and LLE on body weight (BW), food and water consumptions, and enterolactone (ENL) levels in serum and urine of rats was examined at the end of the 5-week treatment period. TP significantly diminished the mean body weight gain (MBWG) of positive control rats and their food and water consumptions while LLE reduced significantly this MBWG reduction in a dose-dependent manner. The lignan-rich extract significantly inhibited TP-induced prostate size ratio (prostate weight/rat BW) increase in comparison with positive controls (P<.001). This effect was dose dependent. Higher serum and urine levels of ENL correlated well with the dose of extract provided to rats. It was concluded that the lignan-rich flaxseed hull extract prevented the TP-induced BPH indicating it might be beneficial in the prevention of BPH.

  6. Effects of experimentally induced low back pain on the sit-to-stand movement and electroencephalographic contingent negative variation.

    PubMed

    Jacobs, Jesse V; Yaguchi, Chie; Kaida, Chizuru; Irei, Mariko; Naka, Masami; Henry, Sharon M; Fujiwara, Katsuo

    2011-11-01

    It is becoming increasingly evident that people with chronic, recurrent low back pain (LBP) exhibit changes in cerebrocortical activity that associate with altered postural coordination, suggesting a need for a better understanding of how the experience of LBP alters postural coordination and cerebrocortical activity. To characterize changes in postural coordination and pre-movement cerebrocortical activity related to the experience of acutely induced LBP, 14 healthy participants with no history of LBP performed sit-to-stand movements in 3 sequential conditions: (1) without experimentally induced LBP; NoPain1, (2) with movement-associated LBP induced by electrocutaneous stimulation; Pain, and (3) again without induced LBP; NoPain2. The Pain condition elicited altered muscle activation and redistributed forces under the seat and feet prior to movement, decreased peak vertical force exerted under the feet during weight transfer, longer movement times, as well as decreased and earlier peak hip extension. Stepwise regression models demonstrated that electroencephalographic amplitudes of contingent negative variation during the Pain condition significantly correlated with the participants' change in sit-to-stand measures between the NoPain1 and Pain conditions, as well as with the subsequent difference in sit-to-stand measures between the NoPain1 and NoPain2 conditions. The results, therefore, identify the contingent negative variation as a correlate for the extent of an individual's LBP-related movement modifications and to the subsequent change in movement patterns from before to after the experience of acutely induced LBP, thereby providing a direction for future studies aimed to understand the neural mechanisms underlying the development of altered movement patterns with LBP.

  7. Efficacy of herbal coded Hepcon on drug induced hepatitis in experimental animals through histopathological and biochemical analysis.

    PubMed

    Jamil, Muhammad Saim; Mahmood, Zahid; Saeed, Aftab; Jamil, Amir; Usmanghani, Khan; Asif, Hafiz Muhammad; Sajjad-al-Hassan; Roohi, Mahira

    2013-09-01

    Drug-induced liver injury is the leading cause for more than 50 percent of cases of acute liver failure. This study was conducted on herbo-mineral formulation "Hepcon" to evaluate its hepatoprotective effects in drug induced hepatitis in experimental animals. The liver injury was introduced with over dosage of non steroidal anti-inflammatory drugs (NSAIDs) and carbon tetrachloride (CCl4). The herbo-mineral formulations "Hepcon" consist of Zingiber officinale, Piprum nigrum, Ammonium chloride and Arsenic trioxide (Hartal warqi). The aqueous extraction was administered to experimental animals. Thereafter their LFTs, IgG, and tissue pathology was studied. It was observed on the basis of biochemical and histopathological analysis that animals which were subjected to Hepcon became normal in 60 days whereas those as control group did not showed improvements and most of them died. It was concluded that the efficacy of Hepcon to treat liver injury caused by CCl4 and NSAIDs is very effective, and no side effects were noticed.

  8. Efficacy of herbal coded Hepcon on drug induced hepatitis in experimental animals through histopathological and biochemical analysis.

    PubMed

    Jamil, Muhammad Saim; Mahmood, Zahid; Saeed, Aftab; Jamil, Amir; Usmanghani, Khan; Asif, Hafiz Muhammad; Sajjad-al-Hassan; Roohi, Mahira

    2013-09-01

    Drug-induced liver injury is the leading cause for more than 50 percent of cases of acute liver failure. This study was conducted on herbo-mineral formulation "Hepcon" to evaluate its hepatoprotective effects in drug induced hepatitis in experimental animals. The liver injury was introduced with over dosage of non steroidal anti-inflammatory drugs (NSAIDs) and carbon tetrachloride (CCl4). The herbo-mineral formulations "Hepcon" consist of Zingiber officinale, Piprum nigrum, Ammonium chloride and Arsenic trioxide (Hartal warqi). The aqueous extraction was administered to experimental animals. Thereafter their LFTs, IgG, and tissue pathology was studied. It was observed on the basis of biochemical and histopathological analysis that animals which were subjected to Hepcon became normal in 60 days whereas those as control group did not showed improvements and most of them died. It was concluded that the efficacy of Hepcon to treat liver injury caused by CCl4 and NSAIDs is very effective, and no side effects were noticed. PMID:24035958

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

    SciTech Connect

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

    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.

  10. Experimental Study of Synchro-Betatron Coupling Induced By Dipole Modulation

    SciTech Connect

    Syphers, M.; Ball, M.; Brabson, B.; Budnick, J.; Caussyn, D.D.; Chao, A.W.; Collins, J.; Derenchuk, V.; Dutt, S.; East, G.; Ellison, M.; Ellison, T.; Friesel, D.; Gabella, W.; Hamilton, B.; Huang, H.; Jones, W.P.; Lee, S.Y.; Li, D.; Minty, M.G.; Nagaitsev, S.; /Unlisted /Indiana U., IUCF /SLAC /Fermilab /Argonne /Brookhaven

    2011-11-04

    Synchro-betatron coupling in a proton storage ring with electron cooling was studied experimentally by modulating a transverse dipole field close to the synchrotron frequency. The combination of the electron cooling and transverse field modulation on the synchrotron oscillation is equivalent to a dissipative parametric resonant system. The proton bunch was observed to split longitudinally into two pieces, or beamlets, converging toward attractors of the dissipative system. These phenomena might be important in understanding the effect of ground vibration on the Superconducting Super Collider beam, and the effect of power supply ripple on the Relativistic Heavy-Ion Collider beam.

  11. [Pathologic anatomy of experimental pneumoconiosis induced by coal dust in different stages of metamorphism].

    PubMed

    Shkutin, A E; Miakishev, I A

    1978-01-01

    The paper presents the results of investigations of experimental pneumoconiosis caused by inhalational administration of coal dust of the III and IV stages of metamorphism, of the similar petrographic composition without quartz admixtures. Coal dust of the IV stage of metamorphism was found to have more marked fibrogenic properties. Within 6-9 months, fibro-dust foci, destructive bronchites and pulmonary emphysema developed. Coal dust of the III stage of metamorphism within the same period causes only the development of cellular-dust foci, catarrhal bronchitis, and slightly manifest emphysema.

  12. Experimentally induced postinhibitory rebound in rat nucleus ambiguus is dependent on hyperpolarization parameters and membrane potential.

    PubMed

    Dean, J B; Czyzyk-Krzeska, M; Millhorn, D E

    1989-06-01

    Postinhibitory rebound (PIR), a transient depolarization subsequent to release from experimental hyperpolarization, was identified and characterized in 81% of the cells studied in the nucleus ambiguus in slices from medulla of rat. Hyperpolarizing current pulses were administered via the recording microelectrode in the bridge-balanced mode to test for PIR. The voltage trajectory was characterized by a depolarizing sag during the pulse, rebound depolarization (PIR) after the pulse and increased input resistance during rebound. The amplitude and time course of PIR were dependent on prepulse membrane potential, pulse amplitude and pulse duration. These results suggest a potential role of PIR in respiratory rhythmogenesis. PMID:2771207

  13. Experimental analysis of energy harvesting from self-induced flutter of a composite beam

    SciTech Connect

    Zakaria, Mohamed Y. Al-Haik, Mohammad Y.; Hajj, Muhammad R.

    2015-07-13

    Previous attempts to harvest energy from aeroelastic vibrations have been based on attaching a beam to a moving wing or structure. Here, we exploit self-excited oscillations of a fluttering composite beam to harvest energy using piezoelectric transduction. Details of the beam properties and experimental setup are presented. The effects of preset angle of attack, wind speed, and load resistance on the levels of harvested power are determined. The results point to a complex relation between the aerodynamic loading and its impact on the static deflection and amplitudes of the limit cycle oscillations on one hand and the load resistance and level of power harvested on the other hand.

  14. Experimental observation of disorder induced self-focusing in optical fibers

    SciTech Connect

    Leonetti, Marco; Karbasi, Salman; Mafi, Arash; Conti, Claudio

    2014-10-27

    We observed disorder induced focusing nonlinearity activated by a monochromatic light beam in optical fibers composed by two kinds of plastics. The two materials, arranged in disordered fashion, support modes with a degree of localization which increases with the intensity of the optical beam. The temporal response of the optical fiber demonstrates the thermal origin of this nonlinearity. Measurements of the localization length as a function of the input power with broadband and monochromatic inputs show the effectiveness of focusing action with respect to the case of homogeneous fibers.

  15. Experimental study on apoptosis induced by semiconductor laser to hair removal and armpit odor treatment

    NASA Astrophysics Data System (ADS)

    Shi, Hongmin; Yan, Min; Zhang, Meijue

    2005-07-01

    Objective: To observe and explore the effects and mechanism of apoptosis on canine induced by Laser. Try to find a new approach to treat of armpit odor with no traumatism. Method: We used different power of semiconductor Laser to irradiate the black hair canine to observe and evaluate the tissue effects with electroscope, flow cytometry and Tunel technique at different period of time after irradiation. Result: The apoptosis has been observed within the hair follicle cells and apocrine gland cells after irradiation. After repeat irradiation in low power level, more apoptosis has been observed. Conclusion: Apoptosis exists in hair follicle cells and apocrine gland cells after Laser irradiation.

  16. Experimental elaboration of faulting induced by fluid-releasing mineral reactions in subduction zones

    NASA Astrophysics Data System (ADS)

    Green, H.; Zhang, J.; Jung, H.; Dobrzinetskaya, L.

    2003-04-01

    Dehydration embrittlement has been cited repeatedly as a potential mechanism for triggering earthquakes at depths where unassisted brittle failure is impossible due to the normal-stress-dependence of friction. We are investigating two different aspects of this problem in the laboratory: (i) dehydration of antigorite under stress where the ΔV of reaction varies from strongly positive to distinctly negative; (ii) deformation of eclogite in which the nominally anhydrous minerals contain small amounts of dissolved H_2O that can lead to faulting induced by very small amounts of melting stimulated by exsolution of H_2O. (i) Antigorite has the largest stability field of the serpentines and is often cited as potentially being the source of most or all mantle earthquakes to a depth of over 200 km. However, like other low-pressure hydrous phases, the net volume change accompanying antigorite dehydration varies from strongly positive at low P to negative at P > ˜2-2.5 GPa. Fracture mechanics theory predicts that dehydration should not induce shear failure if ΔV<0. To test the effect of ΔV on faulting, we have deformed an extensively-serpentinized peridotite at P = 1-6 GPa. We conducted constant strain rate experiments in a Griggs-type apparatus at P = 1.0 - 3.4 GPa and rapid-pumping experiments in a Walker-type multianvil apparatus, culminating in pressures as high as 6 GPa. Independent of the sign of ΔV, specimens subjected to stress during dehydration yielded extremely thin zones of reaction products with shear offset across them. Some were clearly faults whereas others could be precursors to faulting. Fluid released at grain boundaries between antigorite and relict olivine locally produced Mode I cracks &fluid inclusions. (ii) Deformation of "wet" eclogite at 3 GPa and temperatures between the wet and dry solidi induced exsolution of H_2O and formation of very small amounts (<1%) of melt, leading to faulting. At lower temperature the rock was extremely strong but

  17. Dynamic ocular surface and lacrimal gland changes induced in experimental murine dry eye.

    PubMed

    Xiao, Bing; Wang, Yu; Reinach, Peter S; Ren, Yueping; Li, Jinyang; Hua, Shanshan; Lu, Huihui; Chen, Wei

    2015-01-01

    Dry eye disease can be a consequence of lacrimal gland insufficiency in Sjögren's Syndrome or increased tear film evaporation despite normal lacrimal gland function. To determine if there is a correlation between severity effects in these models and underlying pathophysiological responses, we compared the time dependent changes in each of these parameters that occur during a 6 week period. Dry eye was induced in 6-week-old female C57BL/6 mice by exposing them to an Intelligently Controlled Environmental System (ICES). Sixty mice were housed in ICES for 1, 2, 4 and 6 weeks respectively. Twelve were raised in normal environment and received subcutaneous injections of scopolamine hydrobromide (SCOP) 3 times daily for 5 days. Another sixty mice were housed in a normal environment and received no treatment. Corneal fluorescein staining along with corneal MMP-9 and caspase-3 level measurements were performed in parallel with the TUNEL assay. Interleukin-17(IL-17), IL-23, IL-6, IL-1, TNF-α, IFN-γ and TGF-β2 levels were estimated by real-time PCR measurements of conjunctival and lacrimal gland samples (LGs). Immunohistochemistry of excised LGs along with flow cytometry in cervical lymph nodes evaluated immune cell infiltration. Light and transmission electron microscopy studies evaluated LGs cytoarchitectural changes. ICES induced corneal epithelial destruction and apoptosis peaked at 2 weeks and kept stable in the following 4 weeks. In the ICES group, lacrimal gland proinflammatory cytokine level increases were much lower than those in the SCOP group. In accord with the lower proinflammatory cytokine levels, in the ICES group, lacrimal gland cytosolic vesicular density and size exceeded that in the SCOP group. ICES and SCOP induced murine dry eye effects became progressively more severe over a two week period. Subsequently, the disease process stabilized for the next four weeks. ICES induced local effects in the ocular surface, but failed to elicit lacrimal gland

  18. Dynamic Ocular Surface and Lacrimal Gland Changes Induced in Experimental Murine Dry Eye

    PubMed Central

    Xiao, Bing; Wang, Yu; Reinach, Peter