Influence of cellulose nanofiber fluid on flow instability and heat transfer of two-phase closed thermosyphon.

In this research, the geyser phenomenon occurring in a small-diameter two-phase closed thermosyphon (TPCT) was observed and the instability of the device was discussed. Geyser phenomena interfere with the natural circulation of internal working fluids, increasing the thermal resistance of the system and contributing to the instability of the device. This study attempts to improve the thermal performance and stability of the system using cellulose nanofiber (CNF) fluid as the working fluid. The use of CNF fluid was observed to reduce the magnitude of temperature change inside the evaporator of the TPCT significantly. Moreover, it improved the local boiling heat transfer coefficient by 3.1 %, 87.3 %, and 181.2 % on average when the filling ratios are 0.25, 0.5, and 0.75, respectively. Studying the local heat transfer performance and instability will be helpful in designing a more stable TPCT efficiently. Additionally, the findings of this study can be applied to solar thermal power generation or heat pipe research for cooling strategies in computing servers, depending on the input heat load.

Efficacy of a traditional Korean medicine, Chung-Sang-Bo-Ha-Tang, in a murine model of chronic asthma.

Traditional herbal medicines may be viable alternatives to corticosteroid therapy for treatment of asthma. However, the therapeutic mechanisms of herbal compounds remain a matter of considerable debate. This study was performed to evaluate the effects of Chung-Sang-Bo-Ha-Tang (CSBHT), a herbal compound administrated therapeutically to asthma patients for centuries, on airway inflammation and remodeling in a murine model of chronic asthma. BALB/c mice sensitized to ovalbumin (OVA) were chronically challenged with aerosolized OVA for 6 weeks. During the last 2 weeks, some mice were treated daily with CSBHT by intragastric feeding. Dexamethasone (Dex)-treated, phosphate-buffered saline (PBS)-treated, and naive mice served as controls. The effects of CSBHT on airway inflammation, lung pathology, and cytokine production were evaluated. Mice exposed to recurrent airway challenge with OVA had chronic inflammation and characteristics of airway remodeling, including subepithelial fibrosis, epithelial hypertrophy, and goblet cell hyperplasia. CSBHT was as effective as Dex at moderately reducing these changes compared to the PBS-treated mice. In addition, IL-5 and IFN-gamma levels in supernatants of Concanavalin A (Con A)-activated splenocyte cultures were reduced in mice treated with CSBHT. Treatment with CSBHT during the last 2 weeks of challenge modulated airway inflammation and remodeling in a murine model of chronic asthma. Thus, CSBHT may effectively delay the progression of airway inflammation and remodeling.

Proteome analysis of differential protein expression in allergen-induced asthmatic mice lung after dexamethasone treatment.

Asthma has become substantially more prevalent in recent decades and is one of the foremost contributors to morbidity and mortality in industrialized countries. Corticosteroids are among the most effective medications for the treatment of asthma, but some patients do not respond well to corticosteroid treatment. In this study, we characterized the responses to an allergen and identified potential molecular targets of dexamethasone (Dex) treatment in acute asthma. Female BALB/c mice sensitized to ovalbumin (OVA) were challenged with aerosolized OVA for 1 week. During the challenge period, mice were treated daily with Dex by intraperitoneal injection. Phosphate-buffered saline treated and non-challenged mice served as control. Histological evaluation of OVA-induced mice revealed airway inflammation and goblet cell hyperplasia. In addition, interleukin 4 levels and interferon-gamma levels were increased and decreased, respectively. These changes were moderated by Dex treatment. Protein expression profiles were compared in each experimental group by two-dimensional gel electrophoresis and identified using matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry. Some proteins were increased, while others were decreased by Dex treatment. These results indicated that the regulation of protein expression might play a role in the immunological and pathological development of asthma and could be targeted for therapeutic intervention. These results may assist in the development of quantitative diagnostic markers to monitor disease progression or responses to therapy using proteomic approaches.

Quantitative profiling of plasma peptides in asthmatic mice using liquid chromatography and mass spectrometry.

Asthma is increasing in prevalence worldwide as a result of factors associated with a Western lifestyle. However, simple and reliable diagnostic and prognostic markers are yet to be found. In an attempt to identify protein biomarker profiles among small molecular weight ranges, we employed an approach combining liquid chromatography with mass spectrometry, instead of two-dimensional gel electrophoresis (2-DE), which has previously been used to analyze protein expression patterns. Here we described its application to compare plasma peptides from control and chronic asthma mice. Peptides were quantitatively profiled as a multidimensional peptide mass fingerprint by a combination of reverse-phase high-performance liquid chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. They were identified by peptide mass fingerprinting using matrix-assisted laser desorption/ionization time-of-flight/time-of-flight tandem mass spectrometry. In this study, we quantitatively identified the fragment f of complement 3 (C3f), which is important in inflammation. C3f was significantly higher in controls than chronic asthma mice. Our strategy allowed the detection and identification of different plasma peptides between control and chronic asthma mice on a proteomic scale. Therefore, these results suggest that native small peptides detected by non-2-DE techniques may be useful and specific biomarkers of disease.