Demonstration of laser biospeckle method for speedy in vivo evaluation of plant-sound interactions with arugula.

In recent years, it is becoming clearer that plant growth and its yield are affected by sound with certain sounds, such as seedling of corn directing itself toward the sound source and its ability to distinguish stuttering of larvae from other sounds. However, methods investigating the effects of sound on plants either take a long time or are destructive. Here, we propose using laser biospeckle, a non-destructive and non-contact technique, to investigate the activities of an arugula plant for sounds of different frequencies, namely, 0 Hz or control, 100 Hz, 1 kHz, 10 kHz, including rock and classical music. Laser biospeckles are generated when scattered light from biological tissues interfere, and the intensities of such speckles change in time, and these changes reflect changes in the scattering structures within the biological tissue. A leaf was illuminated by light from a laser light of wavelength 635 nm, and the biospeckles were recorded as a movie by a CMOS camera for 20 sec at 15 frames per second (fps). The temporal correlation between the frames was characterized by a parameter called biospeckle activity (BA)under the exposure to different sound stimuli of classical and rock music and single-frequency sound stimuli for 1min. There was a clear difference in BA between the control and other frequencies with BA for 100 Hz being closer to control, while at higher frequencies, BA was much lower, indicating a dependence of the activity on the frequency. As BA is related to changes from both the surface as well as from the internal structures of the leaf, LSM (laser scanning microscope) observations conducted to confirm the change in the internal structure revealed more than 5% transient change in stomatal size following exposure to one minute to high frequency sound of 10kHz that reverted within ten minutes. Our results demonstrate the potential of laser biospeckle to speedily monitor in vivo response of plants to sound stimuli and thus could be a possible screening tool for selecting appropriate frequency sounds to enhance or delay the activity of plants. (337 words).

Mice Deficient in NOX2 Display Severe Thymic Atrophy, Lymphopenia, and Reduced Lymphopoiesis in a Zymosan-Induced Model of Systemic Inflammation.

Patients with chronic granulomatous disease (CGD) who have mutated phagocyte NADPH oxidase are susceptible to infections due to reduced reactive oxygen species production and exhibit autoimmune and inflammatory diseases in the absence of evident infection. Neutrophils and macrophages have been extensively studied since phagocyte NADPH oxidase is mainly found only in them, while the impact of its deficiency on lymphocyte cellularity is less well characterized. We showed herein a zymosan-induced systemic inflammation model that CGD mice deficient in the phagocyte NADPH oxidase gp91phox subunit (NOX2) exhibited more severe thymic atrophy associated with peripheral blood and splenic lymphopenia and reduced lymphopoiesis in the bone marrow in comparison with the wild-type mice. Conversely, the zymosan-exposed CGD mice suffered from more remarkable neutrophilic lung inflammation, circulating and splenic neutrophilia, and enhanced granulopoiesis compared with those in zymosan-exposed wild-type mice. Overall, this study provided evidence that NOX2 deficiency exhibits severe thymic atrophy and lymphopenia concomitant with enhanced neutrophilic inflammation in a zymosan-induced systemic inflammation model.

Genetic Phagocyte NADPH Oxidase Deficiency Enhances Nonviable Candida albicans-Induced Inflammation in Mouse Lungs.

Patients with chronic granulomatous disease (CGD) have mutated phagocyte NADPH oxidase, resulting in reduced production of reactive oxygen species (ROS). While the mechanism underlying hyperinfection in CGD is well understood, the basis for inflammatory disorders that arise in the absence of evident infection has not been fully explained. This study aimed to evaluate the effect of phagocyte NADPH oxidase deficiency on lung inflammation induced by nonviable Candida albicans (nCA). Mice deficient in this enzyme (CGD mice) showed more severe neutrophilic pneumonia than nCA-treated wild-type mice, which exhibited significantly higher lung concentrations of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and keratinocyte-derived chemokine (KC). Neutralization of these proinflammatory mediators significantly reduced neutrophil infiltration. In vitro, production of IL-1ß and TNF-α from neutrophils and that of KC from macrophages was enhanced in nCA-stimulated neutrophils from CGD mice. Expression of IL-1ß mRNA was higher in the stimulated CGD neutrophils than in the stimulated wild-type cells, concomitant with upregulation of nuclear factor (NF)-κB and its upstream regulator extracellular-signal regulated kinase (ERK) 1/2. Pretreatment with an NADPH oxidase inhibitor significantly enhanced IL-1ß production in the wild-type neutrophils stimulated with nCA. These results suggest that lack of ROS production because of NADPH oxidase deficiency results in the production of higher levels of proinflammatory mediators from neutrophils and macrophages, which may at least partly contribute to the exacerbation of nCA-induced lung inflammation in CGD mice.

Myeloperoxidase negatively regulates the expression of proinflammatory cytokines and chemokines by zymosan-induced mouse neutrophils.

OBJECTIVE: We have previously reported that myeloperoxidase-deficient (MPO(-/-)) neutrophils produce greater amounts of macrophage inflammatory protein-2 (MIP-2) upon in vitro stimulation with zymosan than wild-type neutrophils. This study aimed to examine the effect of MPO deficiency on the expression of other cytokines and chemokines. METHODS: Wild-type and MPO(-/-) neutrophils isolated from peritoneal cavity were stimulated with zymosan in vitro. Secretion of MIP-1α, MIP-1ß, interleukin (IL)-1α, IL-1ß, and tumor necrosis factor (TNF)-α by neutrophils was quantified by ELISA. mRNA expression in the neutrophils was analyzed by real-time reverse transcription-PCR, and the phosphorylation of extracellular-signal regulated kinase (ERK) 1/2 and p38 mitogen activated protein kinase (MAPK) in neutrophils was analyzed by western blot. For in vivo studies, mice were inoculated with zymosan intranasally, and the levels of these cytokines and chemokines were measured in the lungs. RESULTS: The MPO(-/-) neutrophils stimulated by zymosan expressed and secreted significantly higher levels of MIP-1α, MIP-1ß, IL-1α, IL-1ß, and TNF-α than the stimulated wild-type cells. Expression of all of these inflammatory mediators was blocked by pre-treatment with BAY11-7082, U0126, and SB203580, which are inhibitors of nuclear factor (NF)-κB, ERK1/2, and p38 MAPK, respectively. Enhanced expression of these inflammatory mediators is associated with elevated activation of ERK1/2 in stimulated MPO(-/-) neutrophils. In vivo, MPO(-/-) mice had significantly higher numbers of alveolar neutrophils and increased production of MIP-1α, MIP-1ß, IL-1α, IL-1ß, and TNF-α relative to the responses seen in wild-type mice within 24 h of zymosan administration. CONCLUSION: MPO deficiency upregulates the expression of several proinflammatory cytokines and chemokines in mouse neutrophils.

Oscillatory instability in slow crack propagation in rubber under large deformation.

We performed experiments to investigate slow fracture in thin rubber films under uniaxial tension using high-viscosity oils. In this system we observed an oscillating instability in slowly propagating cracks for small applied strains. The transition between oscillatory and straight patterns occurred near the characteristic strain at which rubber exhibits a nonlinear stress-strain relation. This suggests that nonlinear elasticity plays an important role in the formation of the observed pattern. This was confirmed by numerical simulation for neo-Hookean and linear elasticity models.