Scientific experiment exploration course of biomedical engineering specialty / 医疗卫生装备

Objective To study the teaching innovation of the scientific experiment exploration course in biomedical engineering specialty based on its characteristics involving in animal physiological parameters acquisition, circuit system design, signal processing and etc. Methods The course aimed to guide the student in observation learning, practice and inquiry with considerations on course significance,basic principles for designing the course,implementation scheme of course teaching, suggestions for course improvement, instances of practical teaching and etc. Results Four basic principles were proposed for course teaching. An implementation scheme was determined with emphases on teaching materials, theory, practice, discussion and exploration. The course had the rule being inquiry, and some suggestions were put forward about student feedback, scientific research progress, experiment platform renewal and etc. Conclusion Teaching practice proves that the improved course contributes to enhancing the student's understanding of experiment exploration of biomedical engineering specialty and to promoting multi-discipline fusion and cross-over personnel training, and thus is of great reference for other universities.

Effects of crocetin on VCAM-1 expression in human umbilical vein endothelial cells and monocyte-endothelial cell adhesion / 药学学报

Crocetin, a naturally occurring carotenoid, possesses antioxidant and antiatherosclerotic properties, of which the underlying mechanism remains unclear. In the present study, we examined the effects of crocetin (0.1, 1, 10 μmol·L(-1)) on angiotensin II (Ang II, 0.1 μmol·L(-1)) induced expression of vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVECs) and monocyte-endothelial cell adhesion. The effects of crocetin on the activation of nuclear factor kappa B (NF-κB) and intracellular reactive oxygen species (ROS) were also observed. The results demonstrated that crocetin notably suppressed Ang II induced NF-κB activation (P<0.01) and VCAM-1 expression (P<0.05, P<0.01) in HUVECs, accompanied by a markedly reduced monocyte-endothelial cell adhesion (P<0.05, P<0.01). In addition, preincubation with crocetin resulted in a significant enhancement of cellular antioxidant capacity (P<0.05, P<0.01), while Ang II induced intracellular ROS decreased markedly (P<0.05, P<0.01). These results indicated that crocetin was capable of suppressing Ang II induced VCAM-1 expression and monocyte-endothelial cell adhesion by suppression of NF-κB activation, which might be derived from the enhancement of antioxidant capacity and subsequent reduction of intracellular ROS.

Preliminary study of wireless biofeedback therapy for treatment of bruxism / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To access the effect of wireless biofeedback therapy on bruxism.</p><p><b>METHODS</b>Ten voluntary bruxers (seven female and three male, mean age 26.1 years) were invited to participate in this clinical research. An electric resistance strain gauge was embedded in the position of canine of a maxillary splint for monitoring the abnormal clenching or grinding movement of teeth during sleep. The relevant details of bruxism events, including value of relative force, occurring time and duration were recorded and analyzed by the receiver device and monitoring program respectively. Meanwhile, for the purpose of nerve system and muscle relaxation, a watch-style device around the patient's wrist will vibrate to alert the patient of teeth grinding or clenching if the value of biting force and duration exceed the threshold. Total average episodes of bruxism and duration was observed during eight hours sleep, and was analyzed with one-way analysis of variance in SPSS 19.0 by the end of 6th week and three months following biofeedback therapy.</p><p><b>RESULTS</b>The average episodes of bruxism has declined dramatically from (9.8 ± 2.2) times to (3.0 ± 1.2) times during one night (P < 0.05), and the average duration of bruxism events was reduced from (20.7 ± 12.2) s to (10.0 ± 3.4) s (P < 0.05) after six weeks biofeedback therapy. By the end of three months, the average episodes declined to (2.9 ± 1.2) times (P < 0.05), and the average duration decline to (9.2 ± 2.9) s (P < 0.05) with contrast to preliminary night.</p><p><b>CONCLUSIONS</b>The pressure-based wireless biofeedback device is able to monitoring clenching and grinding of bruxism. The results suggest that biofeedback therapy may be an effective, novel and convenient measure for treatment of bruxism according to several months therapy.</p>

Effects of triptolide on the production of interferon-gamma in human peripheral blood mononuclear cell and phosphorylation of signal transducer and activator of transcription-1 and production of interleukin-8 / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the effects of triptolide on the production of interferon-gamma (IFN-gamma) in human peripheral blood mononuclear cell (PBMC) and interleukin-8 (IL-8) in HaCaT keratinocytes and phosphorylation of signal transducer and activator of transcription-1 (STAT1) of IFN-gamma signal transduction pathways in HaCaT cells.</p><p><b>METHODS</b>Human PBMC was induced by phytohaemagglutinin (PHA-L) and HaCaT cells were stimulated by recombinant human IFN-gamma (rhIFN-gamma). The productions of IFN-gamma and IL-8 in cells were detected by ELISA. The expression of STAT1 and its phosphorylation were analyzed by Western blot.</p><p><b>RESULTS</b>Triptolide inhibited the production of IFN-gamma in human PBMC induced by PHA-L in a dose-dependent manner (P < 0.05, P < 0.01, P < 0.001) and the 50% inhibitory concentration (IC50) value was 5.96 x 10(-11) mol/L. IL-8 production in HaCaT cells induced by rhIFN-gamma in vitro was also inhibited by triptolide (P < 0.001) and the IC50 value was about 1.15 x 10(-13) mol/L. The expressions of phosphorylated STAT1 in HaCaT cells stimulated by rhIFN-gamma was inhibited by triptolide (P < 0.01) and the IC50 value was about 9.45 x 10(-11) mol/L.</p><p><b>CONCLUSION</b>Triptolide can inhibit the production of IFN-gamma in human PBMC and downregulate IL-8 level in HaCaT keratinocytes induced by rhIFN-gamma. Triptolide can inhibit the phosphorylations of STAT1 of IFN-gamma signal pathway in HaCaT keratinocytes stimulated by IFN-gamma.</p>

Effect of crocetin on cardiac hypertrophy induced by overloading pressure in rats / 药学学报

<p><b>AIM</b>To study the influence of crocetin on cardiac hypertrophy induced by overloading pressure in rats.</p><p><b>METHODS</b>The model of cardiac hypertrophy was produced by overloading pressure in rats. The animals were divided into five groups: sham-operation group (0.5% CMC-Na, ig), model group (operation + 0.5% CMC-Na, ig), captopril group (operation + 50 mg x kg(-1), ig), crocetin I (100 mg x kg(-1), ig) and crocetin II (50 mg x kg(-1), ig). All animals were treated for 30 d by ig. Then, cardiac indexes were examined. The activity of ATPase and the hydroxyproline content in heart were assayed by colorimetric analysis. Matrix metalloproteinases (MMPs) activity was assayed by SDS-PAGE zymography.</p><p><b>RESULTS</b>Compared with the model group, crocetin was found to significantly reduce the cardiac indexes and the content of hydroxyproline in heart, increase the activity of Na+ , K+ -ATPase, Ca2+, Mg2+ -ATPase and inhibit MMPs activity.</p><p><b>CONCLUSION</b>The activity of MMPs may play a key role in the cardiac hypertrophy induced by overloading pressure, and proprably as a result of decreasing the activity of MMPs. Crocetin was shown to prevent remodeling of cardiac hypertrophy induced by overloading pressure.</p>

Effect of crocin on intracellular calcium concentration in cultured bovine aortic smooth muscle cells / 药学学报

<p><b>AIM</b>To study the effect of crocin on intracellular calcium concentration ([Ca2+]i) in cultured bovine aortic smooth muscle cells (BASMCs).</p><p><b>METHODS</b>Cells were loaded with fluorescence probe Fluo-3/AM and [Ca2+]i was measured by laser scanning confocal microscope (LSCM).</p><p><b>RESULTS</b>In the presence or absence of extracellular Ca2+, crocin (1 x 10(-8), 1 x 10(-7), 1 x 10(-6) mol x L(-1)) concentration-dependently inhibited the [Ca2+]i elevation induced by 1 x 10(-2) mol x L(-1) H2O2 (for the former, the inhibition rates were 34.1%, 57.1% and 74.3%, while for the latter were 26.2%, 32.1%, 50.0%). In the absence of extracellular Ca2+, crocin (1 x 10(-8), 1 x 10(-7), 1 x 10(-6) mol x L(-1)) could inhibit the [Ca2+]i elevation induced by 70 mmol x L(-1) CHCl3, the inhibition rates were 27.8%, 27.8% and 50.0% respectively.</p><p><b>CONCLUSION</b>Crocin could inhibit the extracellular Ca2+ influx and release of intracellular Ca2+ stores in endoplasmic reticulum.</p>

Protective effect of crocetin on primary culture of cardiac myocyte treated with noradrenaline in vitro / 药学学报

<p><b>AIM</b>To investigate the cardio-protective effect of crocetin on primary culture of cardiac myocyte treated with noradrenaline.</p><p><b>METHODS</b>After adding crocetin, the primary culture of cardiac myocyte was injured by 1.0 micromol x L(-1) noradrenaline. The activity of lactic dehydrogenase (LDH), mitochondrion succinic dehydrogenase (MSDH) and ATPase were assayed. The mitochondrion membrane potential was detected by Rh123. The percentage of cardiac myocyte apoptosis was observed by flow cytometry.</p><p><b>RESULTS</b>Crocetin significantly decreased the activity of LDH in culture supernatant, increased the activity of MSDH, ATPase (Na+-K+ ATPase, Ca2+ ATPase) and mitochondrion membrane potential.</p><p><b>CONCLUSION</b>Crocetin could alleviate the disturbance of energy metabolism and decrease the percentage of apoptosis of cardiac myocyte treated with noradrenaline.</p>

Pharmacokinetics of crocetin in rats / 药学学报

<p><b>AIM</b>To develop an HPLC method for the determination of crocetin in rat plasma and study the pharmacokinetics in rats.</p><p><b>METHODS</b>Hypersil C18 column (5 microns, 4.6 mm x 200 mm) was used at column temperature 30 degrees C. The mobile phase consisted of methanol-water-acetic acid (75:24.5:0.5) at the flow rate of 1.0 mL.min-1. The UV detection wave length was 423 nm.</p><p><b>RESULTS</b>The calibration curve was linear (gamma = 0.9996) in the range from 0.49 microgram.mL-1 to 7.87 micrograms.mL-1 for crocetin. The mean recovery was 105.2%. The lowest detectable concentration of crocetin was 0.14 microgram.mL-1 (S/N = 3). The RSDs of within-day and between-day were all less than 5%. The plasma crocetin was steady. The HPLC method of determination of crocetin in the plasma was established. After single dose of 50 mg.kg-1 ig in 10 rats, the main pharmacokinetic parameters were estimated as follows: T1/2 alpha (30 +/- 6) min, Tmax(65 +/- 16) min, Cmax(5.0 +/- 1.0) microgram.mL-1, AUC0-T(845 +/- 109) microgram.min.mL-1, Vd(5.0 +/- 0.8) L.kg-1. Crocetin was shown to be absorbed into the blood through the gastrointestinal tract.</p><p><b>CONCLUSION</b>This method is quick, precise and reliable. Crocetin was shown to be quickly absorbed in rats.</p>