Optical excitation and detection of neuronal activity

Optogenetics has emerged as an exciting tool for manipulating neural activity, which in turn, can modulate behavior in live organisms. However, detecting the response to the optical stimulation requires electrophysiology with physical contact or fluorescent imaging at target locations, which is often limited by photobleaching and phototoxicity. In this paper, we show that phase imaging can report the intracellular transport induced by optogenetic stimulation. We developed a multimodal instrument that can both stimulate cells with high spatial resolution and detect optical pathlength changes with nanometer scale sensitivity. We found that optical pathlength fluctuations following stimulation are consistent with active organelle transport. Furthermore, the results indicate a broadening in the transport velocity distribution, which is significantly higher in stimulated cells compared to optogenetically inactive cells. It is likely that this label-free, contactless measurement of optogenetic response will provide an enabling approach to neuroscience.Comment: 20 pages, 5 figure

Diesel exhaust particles exert acute effects on airway inflammation and function in murine allergen provocation models

Background: Epidemiologic studies show that sudden surges in ambient particulate matter (PM) levels can trigger acute asthma exacerbations. Although diesel exhaust particles (DEPs) act as an adjuvant for allergic sensitization, this is a delayed response and does not explain acute PM effects on airway hyperreactivity (AHR). Objective: Our aim was to determine the acute effects of DEPs on AHR using a mouse model. Methods: Three protocols were developed, 2 of which require OVA sensitization, whereas the third was OVA independent. In the mild sensitization protocol BALB/c mice receive intraperitoneal OVA without alum and are then challenged with aerosolized OVA with or without DEPs. In the postchallenge model DEPs are delivered after OVA challenge to animals sensitized by intraperitoneal OVA plus alum. In the third protocol nebulizer DEPs were also delivered to IL-5-overexpressing mice that exhibit constitutive airway inflammation. Animals were subjected to whole-body plethysmography (WBP) and then killed for performance of bronchoalveolar lavage, histology, and serology. Results: DEP delivery concomitant with OVA challenge or after the induction of airway inflammation with this allergen induced increased AHR in models 1 and 2, respectively. Although these animals showed DEP-induced inflammation and mucus production in the intermediary airways, there was no effect on OVA-specific IgE or TH2 cytokine production. In the IL-5 transgenic mice it was possible to induce similar effects with DEPs in the absence of an allergen. Conclusion: We demonstrate that DEPs induced AHR independent of their adjuvant effects, suggesting the use of these models to study the mechanism or mechanisms of acute asthma exacerbation by means of PM

Optimization of Clostridium tyrobutyricum encapsulation by extrusion method and characterization of the formulation

Purpose: To optimize the process parameters for the encapsulation of Clostridium tyrobutyricum (Ct) and to determine its in vitro characteristics.Methods: The process parameters, including the concentration of the wall and hardening material, Ct to gelatin ratio and hardening time, were studied by single factor analysis, while optimization was performed by orthogonal experimental design for the encapsulation rate of Ct.Results: Optimal conditions exhibited by orthogonal experimental design at a 92.17 % encapsulation rate with a viable count of 9.61 ± 0.06 lgCFU/g were: 6 % modified starch, 3 % sodium alginate, and 2 % CaCl2 at a Ct to gelatin ratio of 1:1 with a hardening time of 30 min. The survival rates of encapsulated Ct were higher than free Ct in simulated gastric (6.22 %) and intestinal juices (15.55 %). Reduction in viable counts of Ct at 90 °C were higher for free cells (44.76 %) than encapsulated cells (28.09 %) after 30 min of heat treatment. Correspondingly, encapsulation boosted the capacity of Ct to withstand the strong acidic conditions of the stomach and improved the storage properties of Ct.Conclusion: The results suggested that extrusion is a good technique for the encapsulation of Ct, as it enhances the viability of Ct during their transit through the gastrointestinal tract. Furthermore, encapsulation is favorable for Ct if planned for use in formulations where high temperature treatment is required

Bidirectional regulation of angiogenesis and miR-18a expression by PNS in the mouse model of tumor complicated by myocardial ischemia

BACKGROUND: Panax Notoginseng Saponins (PNS) is the major class of active constituents of notoginseng, a natural product extensively used as a therapeutic agent in China. Tumor when accompanied by cardiovascular disorders poses a greater challenge for clinical management given the paradoxical involvement of angiogenesis, therefore gaining increased research attention. This study aim to investigate effects of PNS and its activity components in the mouse model of tumor complicated with myocardial ischemia. METHODS: Tumor complexed with myocardial ischemia mouse model was first established, which was followed by histological and immunohistochemistry examination to assess the effect of indicated treatments on tumor, myocardial ischemia and tissue specific angiogenesis. MicroRNA (miRNA) profiling was further carried out to identify potential miRNA regulators that might mechanistically underline the therapeutic effects of PNS in this complex model. RESULTS: PNS and its major activity components Rg1, Rb1 and R1 suppressed tumor growth and simultaneously attenuated myocardial ischemia. PNS treatment led to decreased expression of CD34 and vWF in tumor and increased expression of these vascular markers in heart. PNS treatment resulted in reduced expression of miR-18a in tumor and upregulated expression of miR-18a in heart. CONCLUSIONS: Our data demonstrated for the first time that PNS exerts tissue specific regulatory effects on angiogenesis in part through modulating the expression of miR-18a, which could be responsible for its bidirectional effect on complex disease conditions where paradoxical angiogenesis is implicated. Therefore, our study provides experimental evidence warranting evaluation of PNS and related bioactive component as a rational therapy for complex disease conditions including co-manifestation of cancer and ischemic cardiovascular disease

A Comprehensive Education and Prevention Program for Student-Athletes: A Life Skills/Experiential Learning Model

The purpose of this longitudinal drug prevention program sponsored by the NCAA was to provide a unique experiential learning approach for student-athletes. Data were obtained from freshman student-athletes before and after a fall semester drug education course via a questionnaire measuring self-esteem, knowledge, attitudes, frequency of usage, risk factors, and demographic variables. In this program, freshman student-athletes were required to enroll in a one-credit health education "Values and Health" course during the fall semester. Topics included stress management skills, sports nutrition, eating disorders, sexuality, date rape, and, most importantly, five session on alcohol use and abuse. The authors collecgted 158 freshman drug questionnaires prior to the start of the program, and collected 43 post-tests after the course for matched data. They also collected data from 33 senior track athletes. For a control group, they also surveyed 60 club sport athletes and 87 non-athletes. The data for all groups was the Student-Athlete Service Questionnaire which included questions from the Rosenberg Self-Esteem Scale. MANOVAs were computed for four dependent measures (self-esteem, knowledge, attitude, and risk factors) and independent variables (drug user/non-user, subject sex, sprot type, parental income cateogry, financial aid status, and time) were examined for each drug category. The effectiveness of the freshman program was analyzed, and further comparisons were made with other student-athlete and non-athlete groups. Alcohol was found to be the most widely used drug, while use of performance and societal drugs was extremely low. The freshman program was found to have a significant impact on enhancing drug knowledge, as findings indicated freshman athletes (especially in non-contact sports) are at a higher risk for recreational drug use than other athletes and non-athletes. Additional multivariate analyses examined other attitudinal and psychological variables

Comparison of Digital Signal Processing Approaches for Subcarrier Multiplexed 5G and Beyond Analog Fronthaul

Analog fronthaul transport architectures with digital signal processing at the end stations are promising as they have the potential to achieve high spectral efficiencies, increased flexibility and reduced latency. In this paper, two digital techniques for frequency domain multiplexing/de-multiplexing large numbers of channels are contrasted: one operates on the pre-Inverse Fast Fourier Transform (IFFT) “frequency-domain” samples while the other does so on the post-IFFT “time-domain” samples. Performance criteria including computational complexity and sampling rate requirements are used in the comparison. Following modeling and simulation of the techniques, implemented within a radio-over-fiber transport architecture, error vector magnitude performance estimates are obtained. These results show that each technique has performance advantages under specific channel transport scenarios

Compounds purified from edible fungi fight against chronic inflammation through oxidative stress regulation

Chronic inflammation is associated with various chronic diseases, including cardiovascular disease, neurodegenerative disease, and cancer, which severely affect the health and quality of life of people. Oxidative stress induced by unbalanced production and elimination of reactive oxygen species (ROS) is one of the essential risk factors for chronic inflammation. Recent studies, including the studies of mushrooms, which have received considerable attention, report that the antioxidant effects of natural compounds have more advantages than synthetic antioxidants. Mushrooms have been consumed by humans as precious nourishment for 3,000 years, and so far, more than 350 types have been identified in China. Mushrooms are rich in polysaccharides, peptides, polyphenols, alkaloids, and terpenoids and are associated with several healthy biological functions, especially antioxidant properties. As such, the extracts purified from mushrooms could activate the expression of antioxidant enzymes through the Keap1/Nrf2/ARE pathway to neutralize excessive ROS and inhibit ROS-induced chronic inflammation through the NF-κB pathway. Recently, the antioxidant properties of mushrooms have been successfully applied to treating cardiovascular disease (CAD), neurodegenerative diseases, diabetes mellitus, and cancer. The present review summarizes the antioxidant properties and the mechanism of compounds purified from mushrooms, emphasizing the oxidative stress regulation of mushrooms to fight against chronic inflammation