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In view of the characteristics of ultrasound image acquisition and speckle noise statistics, this paper proposes an despeckling algorithm based on polar coordinate system and Monte Carlo estimation scheme. Firstly, it took logarithmic transformation to noisy images in polar coordinate system. Then, it acquired a set of samples in any radial direction with the estimated point in global spatial domain, and constructed weighting factor according to speckle noise model and the spatial correlation between sample point and estimated point. Consequently, the algorithmused the Monte Carlo method to achieve speckle noise likelihood-weighted estimate. Experimental results demonstrate that, the presented algorithm can better remove speckle noise while preserving image structures and details. [ABSTRACT FROM AUTHOR]

Objectives: To observe the effect of electroacupuncture (EA) stimulation of "Dazhui"(GV14) and "Mingmen" (GV4) of the Governor Vessel (GV) on the apoptosis of neurons in rats with spinal cord injury (SCI) by regulating the expression of glycogen synthase kinase-3β (GSK-3β) protein and its phosphorylation level, so as to reveal partial mechanism for the treatment of SCI with EA of GV., Methods: A total of 45 male SD rats were randomly divided into sham-operation, model and EA groups, 15 rats in each group. The SCI model was established by using the modified Allen's percussion device. EA stimulation (2 Hz, 1 mA) was applied to GV14 and GV4 for 20 min, once daily for 28 days. Basso-Beattie-Bresnahan (BBB) locomotor rating scale was used to assess the rat's hind limb motor function at the 1 st , 7 th , 14 th , 21 th and 28 th day after modeling. H.E. staining was used to observe the histopathological changes of the injured spinal cord tissue. The expressions of GSK-3β and its phosphorylation at Ser9 site in the spinal cord were detected by immunohistochemistry and Western blot, respectively. The TUNEL staining was used to observe the apoptosis of neuron in the spinal cord., Results: In comparison with the control group, the BBB scores from day 1 to day 28, and the expression and immunoactivity of p-GSK-3β were significantly decreased ( P <0.01), while the expression and immunoactivity of GSK-3β and the apoptosis index were significantly increased ( P <0.01) in the model group. In contrast to the model group, the EA group had a remarkable increase in the BBB score from day 7 to day 28, and the expression and immunoactivity of p-GSK-3β ( P <0.05, P <0.01), and an obvious decrease ( P <0.05, P <0.01) in the expression and immunoactivity of GSK-3β and the apoptosis index. H.E. staining showed that in the model group, the spinal cord structure of the SCI region was disorganized, with tissue cavity, blurred gray matter boundary, severe inflammatory infiltration, reduction of normal neurons, loss of cytoplasm, and nuclear contraction, which was relatively milder in the EA group., Conclusions: EA at GV14 and GV4 can improve the symptoms of neurological function injury and reduce the apoptosis of neurons in rats with SCI, which may be achieved by regulating GSK-3β protein and its phosphorylation level.

Objectives: To investigate the effect of "Tongdu Qishen" acupuncture［dredging the Govern Vessel and normalizing mental activities, electroacupuncture (EA) of "Baihui" (GV20), "Yintang" (EX-HN3) and "Shuigou" (GV26) needling］on the learning-memory ability and the mechanism of ferroptosis in Alzheimer's disease (AD) mice., Methods: Twenty-four male APPswe/PS1dE9 mice were randomly and equally divided into model group and EA group, and 12 normal C57BL/6 mice were used as the control group. In the EA group, EA (2 Hz/100 Hz, 20 min) was applied to GV20 and EX-HN3 in combination with manual acupuncture stimulation of GV26. The treatment was performed once a day, for a total of 28 days. The mice in the three groups were given the same fixation and grasping operation. Morris water maze swimming tests were used to assess the mice's learning-memory ability. Nissl staining and transmission electron microscopy were used to observe the morphological changes of neurons in the hippocampus. The activity of superoxide dismutase (SOD) in the hippocampus tissue was detected by superoxide anionic colorimetric assay kit (WST-1), and malondialdehyde (MDA) contents were detected by thiobarbituric acid (TBA) method. The expression levels of prostaglandin endoperoxide synthase 2 (ptgs2) and glutathione peroxidase 4 (GPX4) mRNA in the hippocampus were detected by fluorescent quantitative real-time PCR., Results: Behavioral results showed that compared with the control group, the escape latencies at the 2 nd , 3 rd , 4 th and 5 th day of Morris water maze swimming test were significantly increased ( P <0.05), and the swimming time in the original platform quadrant and the times of cros-sing the original platform were considerably decreased ( P <0.05) in the model group. In comparison with the model group, the escape latencies at the 4 th and 5 th day were strikingly decreased ( P <0.05), and the swimming time in the original platform quadrant and times of crossing the original platform significantly increased ( P <0.05) in the EA group. Following modeling, the SOD activity and the expression of GPX4 mRNA were obviously down-regulated ( P <0.05), and the content of MDA and the expression of ptgs2 mRNA significantly up-regulated ( P <0.05) in the model group rele-vant to the control group. The SOD activity and the expression of GPX4 mRNA were apparently increased ( P <0.05), and the content of MDA and the expression of ptgs2 mRNA remarkably down-regulated ( P <0.05) in the EA group rele-vant to the model group. Histopathological and ultrastructural results showed scattered arrangement of cells, widened space among cells, reduction in the number of cells, and many shrunk of dissolved nucleoli, shrunking and incomplete mitochondria, and high membrane electron density in the hippocampus of the model group, which was relatively milder in the EA group., Conclusions: "Tongdu Qishen" acupuncture can improve the learning-memory ability of AD mice, which may be related to its functions in up-regulating SOD activity and GPX4 mRNA expression, and down-regulating MDA content and ptgs2 mRNA expression to reduce the lipid peroxidation in the process of ferroptosis.

Objective: To observe the effect of electroacupuncture(EA) on activities of A2 type astrocytes(A2s)and A1 type astrocytes (A1s) , expressions of neurofilament protein 200 (NF-200, a marker of axon regeneration), nexin 1(NL1, a marker of synaptic regeneration), and regeneration of Nissl bodies in rats with spinal cord injury (SCI), so as to explore its mechanisms underlying improvement of SCI., Methods: A total of 75 male SD rats were rando-mized into sham operation, model, antibody neutralizing (AN), EA and EA+AN groups, with 15 rats in each group. The SCI model was established by using an infinite field impactor to deliver an about 200 k dyne weight onto the exposed spinal cord after making a dorsal laminectomy at vertebral level T10. EA (2 Hz, 1 mA) was applied to"Dazhui"(GV14) and "Mingmen"(GV4) for 20 min, once daily for 28 days. After modeling, intraspinal injection of neutralizing antibodies IL-1α, TNF-α and complement 1q (C1q, 2 μL) to the injured spinal locus for inhibition of A1 type astrocytes (A1s) was conducted on the 1 st , 7 th , 14 th and 21 st day for rats of AN and EA+AN groups. BBB rating scale was used to evaluate hindlimb locomotor function on day 1, 7, 14, 21 and 28 after modeling. The activation of A2s (its specific marker S100a10), astrocyte (its specific marker glial fibrillary acidic protein, GFAP), and A1s (its specific marker C3) in the spinal cord was detected by immunofluorescence, and the protein expressions of NF-200 and NL1 in the spinal cord detected by Western blot and immunohistochemistry, separately, and the neuronal regeneration was observed after Nissl staining., Results: After SCI, the BBB scores at 1 , 7, 14, 21 and 28 day, and the immunoactivity of NL1 and NF-200 were significantly decreased ( P <0.01), and the fluorescence intensity of double labelled S100a10 (A2s)/GFAP and C3, and the expression of NF-200 were considerably increased in the model group ( P <0.05, P <0.01). In contrast to the model group, the BBB scores at 7, 14, 21 and 28 day, and the immunoactivity of NL1 and NF-200, and the fluorescence intensity of A2s/GFAP in the AN, EA and AN+EA groups, and the expressions of NL1 in the EA and AN+EA groups, and expression of NF-200 protein in the AN+EA group were evidently increased ( P <0.05, P <0.01), and the fluorescence intensity of C3 was strikingly decreased in the EA group ( P <0.01). The effect of AN+EA was significantly superior to that of single AN and EA in increasing BBB scores at 14, 21 and 28 day, and in up-regulating the immunoactivity of NF-200( P <0.01, P <0.05). Nissl staining showed damaged structure of the gray matter of the spinal cord, atrophy of the Nissl body, and pyknosis of neurons, which was milder in the AN and EA groups, particularly in the AN+EA group., Conclusion: EA at GV14 and GV4 may promote activation of A2s and promote regeneration of axons and synapses in SCI model rats.

Members of the plant-specific WOX transcription factor family have been reported to play important roles in cell to cell communication as well as other physiological and developmental processes. In this study, ten members of the WOX transcription factor family were identified in Solanum lycopersicum with HMMER. Neighbor-joining phylogenetic tree, maximum-likelihood tree and Bayesian-inference tree were constructed and similar topologies were shown using the protein sequences of the homeodomain. Phylogenetic study revealed that the 25 WOX family members from Arabidopsis and tomato fall into three clades and nine subfamilies. The patterns of exon-intron structures and organization of conserved domains in Arabidopsis and tomato were consistent based on the phylogenetic results. Transcriptome analysis showed that the expression patterns of SlWOXs were different in different tissue types. Gene Ontology (GO) analysis suggested that, as transcription factors, the SlWOX family members could be involved in a number of biological processes including cell to cell communication and tissue development. Our results are useful for future studies on WOX family members in tomato and other plant species.

The present research was planned to develop a method for species concentration measurements under high temperature and pressure environments. The characteristics of CO2 spectrum at high temperature and pressure were studied at first. Based on the research above, tunable diode-laser absorption of CO2 near 2.0 microm incorporating fixed-wavelength modulation spectroscopy with second-harmonic detection was used to provide a method for sensitive and accurate measurements of gas temperature and CO2 concentration at high temperature and pressure. Measurements were performed in a well-controlled high temperature and pressure static cell. The results show that the average error of the CO2 concentration measurements at 5 atm, 500 K and 10 atm, 1000 K is 4. 49%. All measurements show the accuracy and potential utility of the method for high temperature and pressure diagnostics.

The wild resources of Dendrobium officinale in Anhui province were studied by textural research, data collection, interview survey and regional survey, in order to investigate the resources distribution and ecological characters and provide the reference for Anhui Dendrobium industry. In this paper, a part of producing areas of wild D. officinale in Anhui province was selected to analyze the ecological characters. As a result, we find that the wild resources of D. officinale in Anhui distributed only sporadic and the conditions of growth environment were harsh. Our findings may provide some suggestions on wild resources protection and artificial cultivation in suitable environments because the wild resources of D. officinale in Anhui are decreasing rapidly and facing an endangered situation.

In the present paper, the authors focus on the effect of the resonance frequency shift due to the changes in temperature and humidity on the PA signal, present several methods to control the noise derived form gas flow and vibration from the sampling pump. Based on the efforts mentioned above, a detection limit of 1.4 x 10(-8) W x cm(-1) x Hz(-1/2) was achieved for the measurement of atmospheric aerosols absorption coefficient. During the experiments, the PA cell was calibrated with the absorption of standard NO2 gas at 532 nm and the atmospheric aerosols were measured continuously. The measurement results show that the PAS is suitable for the real-time measurement of the absorption coefficient of atmospheric aerosols in their natural suspended state.

A homemade low-temperature T shape photoacoustic system (PAS) in the range from 0 to - 100 degrees C is well established. The mode distribution, the temperature dependence of the resonant frequency, Q-factor and the sensitivity of the PAS were investigated. The measurement of the carbon dioxide in the range from 0 to -100 degrees C showed that the system can be used in trace gas detection under low-temperature. The results show that the PAS can be used to study the atmospheric molecules continuous absorption at low-temperature.

A new cryogenic cell was developed and could operate at any stabilized temperature ranging from room temperature down to 100 K with temperature fluctuation less than +/- 1 K. The structure and performance of the cryogenic cell was given in detail and the temperature stability of the sample cell was evaluated. The methane low temperature absorption spectra at 1.65 microm were recorded at 296, 248, 198 and 176 K and while the characteristic of methane low temperature absorption spectra at 6 039.70 cm(-1) was given. According to the characteristic of our cryogenic cell, we measured the temperature-dependent exponent n of self-broadening coefficient at 6 039. 657 9 cm(-1).

The spectrum of carbon monoxide was obtained around 1. 573 microm using a tunable distributed feedback semiconductor laser with a high-finesse cavity at room temperature via off-axis cavity enhanced absorption (CEA) spectroscopic technique. The absorption line of carbon monoxide at 6 357. 311 6 cm(-1) was chosen for trace detection. Meanwhile, in order to get more accurate measurements, absorption path length of the cavity calibration methods was studied, and a simple and practical calibration method was given. The results show that, the equivalent absorption path length of high-precision optical resonator was -1 195.73 m. At last, we got the concentration of carbon monoxide in the real atmosphere to be -388.346 ppm (S/N = 22), and the detection limit of carbon monoxide was 17.65 ppm. By combination of wavelength modulation technology and OA-CEAS technology, a minimum detectable concentration of 0.36 ppm (S/N = 1 064) was achieved eventually.

In the CH4 absorption spectroscopy measurement, especially the measurements at low temperature, the accurate values of the absorption spectral parameters are very important. The absorption spectral parameters are especially important when the authors use parameters to sense and model the atmospheres of the earth and the outer planets. Sometimes the CH4 parameters listed in the HITRAN 2008 database are uncertain to some extent. In order to measure the low temperature absorption spectroscopy of methane, the authors used a cryogenic cell newly developed by ourselves in combination with a distributed feedback (DFB) diode laser as the light source and measured the low stated energy and the rotational angular momentum. And while the authors compared our data with HITRAN 2008, the authors modeled the line intensity changing with the temperature. The authors' measured parameters will be helpful for sensing and modelling the atmospheres of the earth and the outer planets.

In the present paper the authors designed a vehicle-based remote sensing system using simulated platform and presented a new method of concentration calibration of natural gas pipeline leakage remote sensing. By investigating the performance of different distance, different material, different angle of topographic back scatter and different scan speed, a good coincidence was achieved between experimental results and theoretical results. The system can realize the remote detection of low-level methane concentration at a velocity of 53.3 km x h(-1), and the detecting distance is about 70 m with the minimum detectable sensitivity being 28.9 ppm x m. The research result shows the feasibility in the application.

The high resolution spectrum of methane was obtained around 1.65 microm using a tunable DFB diode laser with a long adjustable optical path white * cell (46.36-1 158.90 m) at room temperature through the direct absorption technique. The typical line width of the DFB diode laser is about 10 MHz and the wavelength of DFB laser was calibrated by an optical wavemeter. A total of 259 new absorption lines were studied from 6 043.00 to 6 053.72 cm(-1) at five different pressures and optical lengths. All the data were fitted by Gaussian profile, the line intensities, positions and the percent of the statistical standard deviation (sigmaS/ S) % of the line intensities were obtained, and the absorption lines which are hard to be distinguished were analyzed in this paper. The weakest absorption line is 4.3 x 10(-27) cm(-1) x (mol x cm(-2))(-1), while the lines stronger than 3.0 x 10(-24) cm(-1) x (mol x cm(-2))(-1) were ignored for their saturated absorption due to the long absorption optical length(788-1 000 m). Meantime, the spectrum shows the abundance of methane weak lines and its extremely complex structure around 1.65 microm. All the lines cannot be found in HITRAN2004 database, and as to our knowledge, they were not reported before by other papers.

A compact instrument based on the off-axis integrated-cavity output spectroscopy (ICOS) technology was developed for sensitive measurements of gas mixing ratios (ammonia in air) at room temperature by using fiber-coupled distributed feedback (DFB) diode laser operating at 1.531 microm. The absorption line of ammonia at 6 528.764 cm(-1) was chosen for trace detection. The mirrors' effective reflectivity R2 of 0.996 9 was first calibrated by carbon dioxide under this condition, and the cavity 35.8 cm in length as an absorption cell could yield an optical path of presumably 115.46 m. As a result, a minimum detectable concentration of approximately 2.66 ppmv (S/N-3) at the total pressure of 100 torr was obtained. Then the lock-in amplifier was added in the system to acquire the second harmonic signal by combination of wavelength modulation technology, which could better suppress background noise and improve the signal-to-noise ratio, and a detection limit of 0.293 ppmv (S/N-3) was achieved eventually. This work demonstrated the potential of the system for a range of atmospheric species sensing in the future.

Stable-isotope ratio analysis of water is an important tool for geology, meteorology, and earth sciences. Measurements of water vapor isotopes are very helpful to explaining stratospheric aridity and related issues in atmospheric sciences. The absorption of water vapor near 2.7 microm is very strong so it is suitable for measuring high sensitivity spectra. Based on difference frequency generation and quasi-phase matching, by mixing an Nd : YAG laser with Ti : Sapphire tunable from 750 to 840 nm in a 50 mm long periodically poled lithium niobate (PPLN) crystal, a widely tunable CW laser source was generated for the mid-infrared spectral range from 2.5 to 4 microm. We chose lambda = 20 microm for PPLN crystal, the generated laser was around 2.7 microm. This laser is widely tunable and of inherent narrow linewidth based on difference-frequency generation. Using this idler laser and 100 m multi-pass cell, and direct absorption the water vapor isotopes were measured in the laboratory air. The authors measured isotopes ratios and delta17O, delta18O and deltaD. The values were found to be in excellent agreement with the standard value for three individual lines.

Measurements strategies based on absorption spectroscopy techniques, especially the measurements in high temperature, require accurate values of important spectroscopic parameters of the probed species. Sometimes the parameters listed in widely used HITRAN and HITEMP2004 database are uncertain to some extent. In order to validate the spectroscopic parameters of 9 selected CO2 lines which should be used in combustion diagnosis, spectra of those lines were recorded in a high temperature experiment setup as a function of temperature (in the range of 300-800 K) and pressure (in the range of 9-450 torr) using a distributed feed-back (DFB) diode laser. The recorded absorption spectra were fitted to Voigt profile. Line intensity, air-broadening coefficient and temperature exponent of each line were deduced from those data. Through comparison of experimental results and those listed in HITRAN and HITEMP2004 database, the discrepancies of most line intensities, air-broadening coefficients and their temperature exponents are less than 3%, 5% and 2% respectively. Those results show good consistency between the experimental data and that in HITRAN and HITEMP2004 database. The discrepancy in line intensities may be caused by the fitting of absorption spectra, the reading of thermocouple and pressure gage, uniformity of temperature in the heated cell, and uncertainty of the optical path. Those factors also cause the discrepancy in air-broadening coefficients and their temperature exponent. CO2 contained in air also introduces error in air-broadening coefficients and their temperature exponent beside those factors. Though we have deducted them in data-processing, the little change of CO2 in partial region also exists. Those results will be helpful to the measurement of CO2 concentration in combustion diagnosis in the future.

Objective: To investigate the effects of ischemic postconditioning (IPost) in protecting hypertrophic myocardium subjected to ischemic-reperfusion (I/R) and to study the role of extracellular regulated protein kinase (ERK1/2) in mediating such protection., Methods: Transverse aortic constriction (TAC) operation was performed on 12-week-old C57/BL mice to establish left ventricular hypertrophy models. Sixty-four isolated TAC mouse hearts were mounted onto the Langendorff perfusion system and randomly divided into 4 equal group: (1) I/R group undergoing stable perfusion for 30 min, ischemia for 30 min, and re-perfusion for 120 min (an I/R cycle) to cause hypertrophic myocardium I/R injury, (2) IPost group undergoing ischemia for 10s and reperfusion for 10s, totally 3 cycles (60s) before reperfusion for 120 min, (3) I/R+ PD98059 (an ERK1/2 inhibitor) group undergoing perfusion of Krebs-Henseleit (KH) buffer with PD98059 10(-5)mol/L for 15 min and perfusion of KH buffer without PD98059 at the beginning of re-perfusion, and (4) IPost + PD98059 group undergoing 3 cycles of IPost and perfusion of KH buffer with PD98059 10(-5)mol/L for 15 min at the beginning of re-perfusion. Hemodynamic examination was conducted 120 min after re-perfusion to measure the left ventricular systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), maximal uprising velocity of left ventricle pressure (dp/dt(max)), and minimal uprising velocity of left ventricle pressure (dp/dt(min)). After the I/R procedure the myocardium of the left ventricle was isolated to detect the infarction size (IS). Western blotting was used to detect the protein expression of extracellular signal-regulated kinase (ERK) 1/2, phosphorylated ERK1/2, Bcl-2, Bax, and mitochondrial and cytosolic cytochrome (Cyt). C. TUNEL was used to detect the apoptotic rate., Results: The LVSP and dp/dt(max) levels of the IPost group were (85 +/- 4) mm Hg and (3811 +/- 230) mm Hg/s, both significantly higher than those of the I/R group [(68 +/- 5) mm Hg and (2830 +/- 230) mm Hg/s respectively, both P < 0.05]. Compared with the I/R group, the protein levels of phosphorylated ERK1/2, Bcl-2, mitochondrial CytC of the IPost group were all significantly higher, the protein levels of Bax and cytosolic CytC, and apoptosis index were significantly lower (all P < 0.05), and the IS was smaller (P < 0.05). I/R + PD98059 showed no effects on the above-mentioned parameters. However, the results of the IPost + PD98059 group showed that in the first 15 min of reperfusion addition of PD98059 reversed all changes observed in the IPost group and eliminated the IPost protection by increasing IS to a level similar to that in the I/R group., Conclusion: IPost has protective effect in hypertrophic myocardium with I/R injury in vitro. ERK1/2 signaling pathway is involved in the protection of IPost by regulating the myocyte apoptosis.

High sensitivity incoherent broadband cavity enhanced absorption spectroscopy based on high power LED was developed. The detection sensitivity was demonstrated by measuring the absorption of NO2 over the wavelength range of 472. 3-479. 3 nm. A broadband incoherent light (emitting from high power LED peaked at 457 nm) was coupled to a 92.5 cm long high finesse optical cavity consisting of two 30 mm diameter plano-concave mirrors (1.0 m radius of curvature) with reflectivity of -0.997 (provided by manufacturer). The light leaked out of the cavity was collected by a compact CCD spectrometer (HR 2000). The cavity mirror reflectivity over the wavelength range of 472.3-479.3 nm was determined from the absorption of O2-O2 collisional pair. A series of concentrations of NO2 samples at high dilution were retrieved using differential spectral fitting techniques, with statistical uncertainties approaching 3.1 ppb (ng x mL(-1)) for a 80 s averaging period.

Photoacoustic spectroscopy (PAS) based on tunable diode laser (TDLPAS) is a widely recognised method for its excellent performance in trace gas monitoring and spectral analysis. This spectral technique provides many advantages such as high selectivity and sensitivity, on-line, real time and contactless measurements in a compact experimental arrangement. In the present paper, a resonant PA spectrometer based on a low-power near infrared distributed feedback (DFB) diode laser and a home-made resonant PA cell operating on its first longitudinal mode is developed, and the PA system has the advantage of simple experimental setup, easy operation, and low-cost, room temperature operating, etc. By investigating the performances of the PA cell at first, a good agreement was achieved between experimental and theoretical results; we have systematically investigated the influence of molecular relaxation effect on the PA detection of CO2 molecule near 1.573 microm, and presented the relevant analysis in theory. The research result shows that the detection sensitivity of the system based on PAS technique can be effectively improved by using the molecular relaxation effect.

Objective: To explore the effects of ischemia postconditioning (IPC) on ischemia-reperfusion (I/R) injury and associated reperfusion injury salvage kinase (RISK) signal transduction pathways changes in isolated mouse hearts., Methods: Langendorff perfused C57/BL mouse hearts were divided to 6 groups: (1) control: 30 min global ischemia and 2 h reperfusion (I/R); (2) IPC with 3 episodes, IPC with 3 episodes of 10 s of ischemia and 10 s reperfusion after 30 min ischemia and before 2 h reperfusion; (3) IPC with 6 episodes, IPC with six episodes of 10 s of ischemia and 10 s reperfusion after 30 min ischemia and before 2 h reperfusion; (4) delayed IPC, IPC with 3 episodes of 10 s of ischemia and 10 s reperfusion after 30 min ischemia and at one minute after reperfusion; (5) IPC + ERK1/2 inhibitor PD98059 (10(-5) mol/L for 15 min); (6) I/R + ERK1/2 inhibitor PD98059 (10(-5) mol/L for 15 min). The effects of IPC on hemodynamics, coronary artery flow, creatine kinase (CK) and lactate dehydrogenase (LDH) release, myocardial SOD, MDA, phospho-protein kinase (P-ERK1/2) and phospho-protein kinase B (P-Akt) as well as myocardial infarction size were measured., Results: IPC with 3 episodes and IPC with 6 episodes significantly and equally improved myocardial function, increased myocardial SOD, reduced CK and LDH release and myocardial infarction size compared with IR group (all P < 0.01) while these parameters were similar between I/R hearts and delayed IPC hearts. IPC significantly increased myocardial ERK1/2 phosphorylation, PD98059 inhibited the phosphorylation of ERK1/2 and abolished the cardioprotective effects induced by IPC., Conclusions: IPC obviously attenuated I/R injury in isolated mouse hearts, the cardioprotection of IPC was not enhanced because of increasing of IPC episodes and disappeared in delayed IPC. The cardioprotective effects of IPC were mediated through ERK1/2-MAPK signal transduction pathway.

The continuously tunable laser source has been realized in a periodically poled LiNO3 crystal based on difference frequency generation and quasi-phase-matching technique. The pump laser is an 1 W tunable Ti: Sapphire laser with a tunable region from 770 to 870 nm. The signal laser is an 1 W diode-pumped monolithic Nd : YAG laser. When the grating period is 20 microm and the temperature is tuned between room temperature and 200 degrees C, the generated wavelength of idler laser is around 2. 8 microm with the general power of .1-2 microW. The direct absorption spectra of (001 <-- 000) band of water in laboratory air were measured based on the laser source. The concentration of water vapor in the laboratory air was estimated with an absorption optical path of 8. 5 cm in open air.

The leak of natural gas is not only an economic loss, but also the fountain of danger. Conventional detection techniques of natural gas pipe leak have low efficiency and slow respond time, therefore, it is difficult for them to suit practice application. Optical sensors based on NIR tunable diode laser absorption spectroscopy were widely used because of high sensitivity, small volume and less maintenance. In the present paper, a portable remote sensor of natural gas pipeline leak was reported. The sensor used a ratio of second to first harmonic signals as calibration method, and the results show a good consistency between the concentrations and the ratios of second to first harmonic signals. The effect of different topographic scattering targets on the ratio detection was measured and analyzed. The results show that the ratio of second to first harmonic signals can be used in practical application.

Fifteen new absorption lines were observed when studying CO2 absorption spectroscopy by wavelength modulation (WM) technique with a DFB laser. The line intensity we can detect is 2.251 63 x 10(-27) cm(-1) x (moleculecm(-2))(-1) at 6.67 x 10(2) Pa pressure, corresponding to an absorbance of 3. 88 x 10(-8). The overtone spectra of CO2 around 1.31 microm have been measured with a tunable diode laser and the corresponding spectral parameters (positions, intensities, and self-broadening coefficients) are presented.

Cavity enhanced absorption spectroscopy (CEAS) is a new spectral technology that is based on the cavity ring down absorption spectroscopy. In the present paper, a DFB encapsulation narrow line width tunable diode laser (TDL) was used as the light source. At the center output, the TDL radiation wavelength was 1.573 microm, and an optical cavity, which consisted of two high reflectivity mirrors (near 1.573 microm, the mirror reflectivity was about 0.994%), was used as a sample cell. A wavemeter was used to record the accurate frequency of the laser radiation. In the experiment, the method of scanning the optical cavity to change the cavity mode was used, when the laser frequency was coincident with one of the cavity mode; the laser radiation was coupled into the optical cavity and the detector could receive the light signals that escaped the optical cavity. As a result, the absorption spectrum of carbon dioxide weak absorption at low pressure was obtained with an absorption intensity of 1.816 x 10(-23) cm(-1) x (molecule x cm(-2)(-1) in a sample cell with a length of only 33.5 cm. An absorption sensitivity of about 3.62 x 10(-7) cm(-1) has been achieved. The experiment result indicated that the cavity enhanced absorption spectroscopy has the advantage of high sensivity, simple experimental setup, and easy operation.

Objective: Autoreactive T cells play a critical role in pathogenesis of systemic lupus erythematosus (SLE). Immunization with inactivated autoreactive T cells (T cell vaccination) may activate the idiotype anti-idiotypic network to deplete specific subsets of autoreactive T cells involved in SLE. We conducted a pilot clinical trial of T cell vaccination to investigate the efficiency and safety of T cell vaccination in treatment of SLE., Methods: Autoreactive T cell clones were derived from peripheral blood mononuclear cells of 6 SLE patients. After irradiated with 80 Gy gamma radiation, 1 x 10(7) T cells were inoculated subcutaneously at 0, 2, 6, 8 week respectively. The patients were followed up for 20-27 months, and monitored for clinical characteristics and side effects from the vaccination., Results: The clinical manifestations and laboratory abnormalities were improved after inoculation without increasing the dose of corticosteroids and immunosuppressants in most patients. SLEDAI score were decreased remarkably. Proliferative responses against the T cell vaccine were observed in 4/6 patients. No side effect was noticed and CD3+, CD4+ and CD8+ T cell were all in normal ranges after the vaccination and during the follow-up period., Conclusion: The results of this pilot study indicate that T cell vaccination is a safe and effective treatment in SLE patients.

Objective: To compare the sensitivity and specificity of four kits for detection of anti-severe acute respiratory syndrome (SARS)-CoV IgG in sera of SARS patients., Methods: Anti-SARS-CoV IgG was detected in 99 serial sera from 18 SARS patients and in 123 negative reference sera, using two enzyme linked immunosorbent assays (EIA No. A and No. B) and two indirect immunofluorescence assays (Australian IFA and Euroimmun IFA)., Results: Anti-SARS-CoV IgG was not detected in sera collected from SARS patients at the first week after onset by any of the four kits, however, it was detectable in sera obtained at the second week of illness by EIA No. B, and two IFA, but not by EIA No. A, with the positive rates of 57.1% (4/7), 57.1% (4/7) and 42.9% (3/7), respectively. The anti-SARS-CoV IgG was first determined in sera on the 9th day by Euroimmun IFA, 12th day by EIA No. B, 13th day by Australian IFA, and 16th day by EIA No. A. The positive rates of antibody on the 3rd week after onset were 84.2% (16/19), 94.7% (18/19), 78.9% (15/19) and 52.6% (10/19) respectively. They were identical since the 4th week after the disease onset. Through detection of 123 negative reference sera, the specificity of EIA No. A and two IFA was 100%, with exception of 94.9% for EIA No. B., Conclusion: The sensitivity and specificity of the two IFAs were relatively higher than that of the two EIAs. The quality of the two homemade EIAs should be improved.

Objective: To study the pathologic characteristics and pathogenesis of circulating blood leucocytes infected by severe acute respiratory syndrome associated coronavirus (SARS CoV or SCV) in SARS patients., Methods: Blood samples of 22 SARS patients were studied, and 4 healthy blood samples were observed as negative controls. The white blood cells were collected from whole blood. The ultrastructural characteristics were observed by transmission electron microscopy. CD45RO antibody was used for pre-embedding immunoelectron microscopy. The SARS viral sequence was detected with real-time polymerase chain reaction (RT-PCR)., Results: Coronavirus-like particles were founded in the leukocytes in 6 of the 22 blood samples. Five of them gave positive results in the real-time PCR. The number of granulocytes was increased (P < 0.05) and that of lymphocytes was decreased (P < 0.05) respectively. Immunoelectron microscopy showed that CD45RO positive T lymphocyte decreased to 6% - 7%. Circulating lymphocytes had the highest percentage of infection. The morphologic characteristics of coronavirus-like particles were spherical or oval in shape, about 80 - 120 nm in diameter, with a dense round core and a clear halo around the core. A distinct membrane and club-shaped surface projections were seen in the periphery. The particles were located in the cytoplasm, the cisternae of endoplasmic reticulum, Golgi apparatus and vesicles. Virus entered cells by endocytosis or membrane fusion and was released through a budding process., Conclusion: Our data suggested that lymphocytes, particularly T cells, were probably the target cells of SARS CoV. The viruses may actively infected the immune cells during SARS CoV acute infection phase and the destruction of target cells may be one of the important reasons for the death of the circulating leukocytes in SARS.