Enzyme-mediated one-pot synthesis of hydrogel with the polyphenol cross-linker for skin regeneration.

Polyphenols can trigger immunity that activates intracellular anti-inflammatory signaling and prevents external infections. In this study, we report the fabrication of chitosan-based hydrogels with epigallocatechin gallate (EGCG) using enzyme-mediated one-pot synthesis. The tyrosinase-mediated oxidative reaction of the phenolic rings of EGCG with the primary amines on chitosan results in stable EGCG-chitosan hydrogels. The EGCG concentrations contributed to the cross-linking density and physical properties of EGCG-chitosan hydrogels. Furthermore, EGCG-chitosan hydrogels maintained intrinsic properties such as antibacterial and antioxidant effects. When endotoxin-activated RAW 264.7 macrophage cells were cultured with EGCG-chitosan hydrogels, the hydrogels reduced the inflammatory response of the RAW 264.7 cells. Furthermore, subcutaneous implantation of EGCG-chitosan hydrogels reduced endogenous macrophage and monocyte activation. When the EGCG-chitosan hydrogels were applied to a full-skin defect wound, they facilitated skin regeneration. Our study demonstrates that the one-pot synthesized EGCG-chitosan hydrogels can be applied in broad tissue regeneration applications that require immune modulation.

Febrile neutropenia and its associated hospitalization in breast cancer patients on docetaxel-containing regimen: A retrospective cohort study on duration of prophylactic GCSF administration.

PURPOSE: To compare febrile neutropenia (FN) incidence and hospitalization among breast cancer patients on docetaxel with no granulocyte colony-stimulating factors (GCSF) primary prophylaxis (PP), 4/5-day PP, or 7-day PP. METHODS: We identified 3916 breast cancer patients using docetaxel-cyclophosphamide (TC), doxorubicin-cyclophosphamide then docetaxel (AC-T), fluorouracil-epirubicin-cyclophosphamide then docetaxel (FEC-T), docetaxel-carboplatin-trastuzumab (TJH), or docetaxel-doxorubicin-cyclophosphamide (TAC) from a hospital pharmacy dispensing database in Hong Kong between 2014 and 2016. Patients were offered GCSF within 5 days since administering docetaxel. Outcomes included FN incidence, time to first hospitalization, hospitalization rate, and duration. RESULTS: In TC regimen, FN incidence (with odds ratio, OR) of patients with no PP, 4/5-day PP, and 7-day PP was 21.69%, 7.95% (OR 0.31, p < 0.001), and 5.33% (OR 0.20, p < 0.001), respectively. In TJH regimen, FN incidence of patients with no PP, 4/5-day PP, and 7-day PP was 38.26%, 8.33% (OR 0.15, p < 0.001), and 8.57% (OR 0.15, p < 0.001), respectively. FN incidence of patients on AC-T regimen with no PP and 4/5-day PP was 20.93% and 6.84%, respectively (OR 0.28, p = 0.005); with FEC-T regimen, the incidence was 9.91% and 4.77%, respectively (OR 0.46, p = 0.035). Only 3.27% FN cases were not hospitalized. Mean (±standard deviation, SD) time to first hospitalization was 8.21 ± 2.44 days. Mean (±SD) duration of hospitalization for patients with no PP, 4/5-day PP, and 7-day PP was 4.66 ± 2.60, 4.37 ± 2.85, and 5.12 ± 2.97 days, respectively. CONCLUSION: GCSF prophylaxis in breast cancer patients on docetaxel could reduce FN incidence and hospitalization. 4/5-day PP demonstrated similar efficacy to 7-day PP with superior saving benefits on healthcare expenditure.

The regulation of oxytocin receptor gene expression during adipogenesis.

Although it has been reported that oxytocin stimulates lipolysis in adipocytes, changes in the expression of oxytocin receptor (OTR) mRNA in adipogenesis are still unknown. The present study aimed to investigate the expression of OTR mRNA during adipocyte differentiation and fat accumulation in adipocytes. OTR mRNA was highly expressed in adipocytes prepared from mouse adipose tissues compared to stromal-vascular cells. OTR mRNA expression was increased during the adipocyte differentiation of 3T3-L1 cells. OTR expression levels were higher in subcutaneous and epididymal adipose tissues of 14-week-old male mice compared to 7-week-old male mice. Levels of OTR mRNA expression were higher in adipose tissues at four different sites of mice fed a high-fat diet than in those of mice fed a normal diet. The OTR expression level was also increased by refeeding for 4 h after fasting for 16 h. Oxytocin significantly induced lipolysis in 3T3-L1 adipocytes. In conclusion, a new regulatory mechanism is demonstrated for oxytocin to control the differentiation and fat accumulation in adipocytes via activation of OTR as a part of the hypothalamic-pituitary-adipose axis.

The Regulation of Chemerin and CMKLR1 Genes Expression by TNF-α, Adiponectin, and Chemerin Analog in Bovine Differentiated Adipocytes.

Adipokines, adipocyte-derived protein, have important roles in various kinds of physiology including energy homeostasis. Chemerin, one of adipocyte-derived adipokines, is highly expressed in differentiated adipocytes and is known to induce macrophage chemotaxis and glucose intolerance. The objective of the present study was to investigate the changes of chemerin and the chemokine-like-receptor 1 (CMKLR1) gene expression levels during differentiation of the bovine adipocyte and in differentiated adipocytes treated with tumor necrosis factor-α (TNF-α), adiponectin, leptin, and chemerin (peptide analog). The expression levels of the chemerin gene increased at d 6 and 12 of the differentiation period accompanied by increased cytoplasm lipid droplets. From d 6 onward, peroxisome proliferator-activated receptor-γ2 (PPAR-γ2) gene expression levels were significantly higher than that of d 0 and 3. In contrast, CMKLR1 expression levels decreased at the end of the differentiation period. In fully differentiated adipocytes (i.e. at d 12), the treatment of TNF-α and adiponectin upregulated both chemerin and CMKLR1 gene expression levels, although leptin did not show such effects. Moreover, chemerin analog treatment was shown to upregulate chemerin gene expression levels regardless of doses. These results suggest that the expression of chemerin in bovine adipocyte might be regulated by chemerin itself and other adipokines, which indicates its possible role in modulating the adipokine secretions in adipose tissues.

Effect of ultrasonic treatment on swine wastewater solubilization.

In order to accelerate hydrolysis known to be the rate-limiting step of the overall digestion process for swine wastewater, an ultrasonic treatment process was tested for the solubilization of the swine wastewater. The effectiveness of ultrasonic solubilization of the swine wastewater under various operational conditions was compared by means of an increment of soluble organics in the treated swine wastewater and the hydrolysis rate constant. Ultrasonic treatment resulted in the high degree of solubilization of particulate organics in the swine wastewater and the degree of solubilization increased with increasing supplied energy. The highest extent of an increment of SCOD concentration and SCOD/TCOD ratio at the end of the operation time of 60 min was 109.7 and 117.5%, respectively, under 120 W power output and 20(o)C operating temperature conditions. The observed highest hydrolysis rate constant described by pseudo-first order rate constant was 2.94 h(-1) under the same conditions. Based on the estimated activation energy from modeling using the Arrhenius equation, ultrasonic solubilization of the swine wastewater under higher supplied energy conditions was more dependent on the operating temperature, which was consistent with the experimentally obtained results. Based on the investigation into the effect of gas type and gas delivery methods for ultrasonic solubilization of the swine wastewater, oxygen gas bubbling through the liquid showed the highest degree of an increment of soluble organics possibly attributed to the influent of oxygen in an increase of radicals during the sonolysis.

Purification and properties of ß-amylase from Bacillus circulans S31.

A thermotolerant ß-amylase was purified from Bacillus circulans S31 isolated from soil in Hong Kong. The purified enzyme has an M r of 64 kDa and was stable at 50°C and pH 7.0 for 30 min. Its K m for starch was 0.9 mg/ml with a V max of 0.3 mg/min. It was not activated by any metal ion although sulphydrys reagents were inhibitory.

Production of thermotolerant ß-amylase byBacillus circulans.

An isolate from a Hong Kong soil sample which produced ß-amylase was identified as a thermotolerant strain ofBacillus circulans with a growth range of 35 to 55δC. The ß-amylase was stable at 45°C for 30 min but lost half of its activity after 30 min at 50°C. Maximum specific activity of ß-amylase (36.2 units/mg protein) in the culture broth was detected after 36 h of cultivation at 45°C in a medium containing soluble starch, beef extract, coconut water and inorganic salts.