Comparison of protective effects of safflor injection and extract of Ginkgo biloba on lung ischemia/reperfusion injury in rabbits.

OBJECTIVE: To observe the protective effects of safflor Injection (SI) and extract of Ginkgo biloba (EGB) on lung ischemia-reperfusion injury (LIRI) and investigate its mechanism. METHODS: In vivo rabbit model of LIRI was reconstructed. Forty rabbits were randomly and equally divided into four groups: sham-operation group (sham group), ischemia-reperfusion group (model group), ischemia-reperfusion plus SI group (safflor group) and ischemia-reperfusion plus EGB injection group (EGB group). Malondialdehyde (MDA) content, superoxide dismutase (SOD) and xanthine oxidase (XO) activity in serum were measured. The wet/dry weight ratio (W/D) of the lung tissue and activity of myeloperoxidase (MPO) were also tested. Ultrastructure change of the lung tissue was observed by the electron microscope. The expression of intercellular adhesion molecule-1 (ICAM-1) was measured by immunohistochemistry (IHC). RESULTS: In the model group, MDA and XO increased and SOD decreased in serum compared with the sham group (P<0.01). The values of W/D, MPO and ICAM-1 of the model group were higher than those of the sham group (P<0.01), but those of the safflor group and EGB group were significantly lower than those of the model group (P<0.01). The IHC demonstrated that ICAM-1 expression in lung tissue of the model group was significantly higher than those of the safflor group (P<0.01). Compared with safflor group, in the EGB group MDA, XO, MPO decreased, SOD and ICAM-1 expression increased (P<0.05), but the change of W/D was not statistically significant (P>0.05). CONCLUSIONS: SI and EGB may attenuate LIRI through antioxidation, inhibition of neutrophil aggregation and down-regulation of ICAM-1 expression. But EGB had more effect on the antioxidation, while SI did better on regulating ICAM-1 expression.

Unbalanced MMP/TIMP-1 expression during the development of experimental pulmonary fibrosis with acute paraquat poisoning.

Paraquat (PQ)-induced pulmonary toxicity is known to result in pulmonary edema, infiltration of inflammatory cells and damage to the alveolar epithelium, which may progress to severe fibrosis. Matrix metalloproteinases (MMPs) and their physiological inhibitors, tissue inhibitors of matrix metalloproteinases (TIMPs), which degrade and remodel the excess extracellular matrix, are believed to play an important role in the development of fibrotic tissue. In this study, we examined the sequential expression of MMP-2, MMP-9 and TIMP-1 in a rat model of pulmonary fibrosis induced by PQ. Adult male Sprague-Dawley rats were treated intraperitoneally with PQ (20 mg/kg) and saline (control group). Rats were sacrificed at days 1, 3, 7 and 21 after the PQ treatment. Lungs were excised for histological evaluation and immunohistochemical analyses, as well as the determination of collagen content, gene expression by fluorimeter-based quantitive RT-PCR assay and gelatinolytic activity by zymography. Lung MMP-2 and -9 mRNA expression progressively increased and reached a peak on day 7 after PQ treatment, while TIMP-1 mRNA levels in the PQ-treated lungs reached a peak on day 21 after modeling. Lung zymography revealed an increase in progelatinase B, progelatinase A and their active forms. In conclusion, unbalanced MMP/TIMP-1 expression and excessive gelatinolytic activity contribute to PQ-induced pulmonary fibrosis. Their precise role should be studied in depth as they may represent relevant therapeutic targets for PQ poisoning-induced pulmonary fibrosis.

A thermostat chip of indium tin oxide glass substrate for static polymerase chain reaction and in situ real time fluorescence monitoring.

A thermostat chip of indium-tin oxide glass substrate for static chip polymerase chain reaction (PCR) is, for the first time, introduced in this paper. The transparent conductive layer was used as an electro-heating element. Pulse width modulation and fuzzy proportional integration-differentiation algorithm were adopted in the temperature programming of the chip. The temperature distribution was investigated, and a dynamic control precision within +/-2 degrees C was achieved. The highest ramping rates were 37 degrees Cs(-1) for heating and 8 degrees Cs(-1) for cooling with an electric fan. The PCR reaction vials were constructed with polyethylene tubes or poly(dimethylsiloxane) directly on the thermostat chip; the chip had a typical size of 25 mm x 25 mm and a thickness of 1.1mm. Static chip PCR was successfully demonstrated either in a single vial or in an up to 8-parallel array vials. In situ real time fluorescence monitoring during PCR of a lambda DNA fragments (236bp) with SYBR Green I was demonstrated using a blue light emission diode as a light source and a photomultiplier as a detector. The method proposed here is characterized by open access, easy fabrication and low cost. This work could be the basis for developing a portable real time PCR system with disposable chips for point of care tests.

Optimization of direct whole blood PCR amplification with applications on a static thermostat chip.

In this paper, direct whole blood PCR amplifications on a static chip thermostat without sample purifications are demonstrated; in these amplifications, problems such as cross-interferences and contaminations could be avoided. The amplification conditions, such as the compositions of reagents and thermal programs, were investigated systematically by a GeneAmp PCR system with a native p53 gene segment (about 543 bp) of human genome and an exterior lambda DNA segment (about 500 bp) as targets. Direct amplifications of p53 and K-ras (about 157 bp) gene segments from 0.5 microL blood samples were successfully demonstrated by a static PCR chip with an indium tin oxide glass substrate. The chip thermostat has a typical size of 25 mm x 25 mm, and a polyethylene tube was used as the PCR vial on the glass surface of the chip. Fuzzy proportional integration-differentiation algorithms were adopted in temperature controls of the chip with an aid of a micro-Pt100 sensor. In the direct PCR with the thermostat chip, the whole process only involves automatic thermal programs. This work demonstrated that a chip PCR for field test without desktop facilities is possible either for a point of care test or for forensic analysis.