Estimation of SPAD value in waterlogged winter wheat based on characteristic indices of hyperspectral and digital image.

To explore the optimal monitoring method for soil and plant analyzer development (SPAD) of winter wheat under waterlogging stress based on hyperspectral and digital image techno-logy, the correlations between SPAD of the waterlogged winter wheat and fifteen indices of hyperspectral characteristic and fourteen indices of digital image feature were analyzed under a micro-plot which could be irrigated and drainage separately. Then, the BP neural network models for SPAD estimation were constructed based on the optimal monitoring feature indices. Compared with the normal winter wheat, SPAD and the value of hyperspectral reflectance did not change under short-term waterlogging (less than 7 d), whereas the SPAD was significantly decreased after more than 12 d waterlogging treatment with the value being close to zero at the late stage of growth. The estimation accuracy based on the digital image characteristics of green minus red, excess red index, norma-lized redness index and excess green index showed similar results compared to that using the BP network model based on the characteristics of the corresponding hyperspectral band. The highest R2 between the measured value and the predicted value was 0.86, while the root mean square error (RMSE) was 3.98. Compared with the BP network models built with the digital image feathers, the accuracy of the models based on the four hyperspectral characteristic indices (carotenoid reflex index, yellow edge amplitude, normalized difference vegetation index and structure insensitive pigment index) for SPAD was significantly improved, with the highest R2 of 0.97 and the lowest RMSE of 1.95. Our results suggest that both hyperspectral and digital image technology could be used to estimate SPAD value of waterlogged winter wheat and that the BP network model based on hyperspectral characteristic indices performed better in the estimation accuracy.

Endothelial nitric oxide synthase gene polymorphisms associated with susceptibility to high altitude pulmonary edema in Chinese railway construction workers at Qinghai-Tibet over 4 500 meters above sea level / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To examine whether the polymorphisms of endothelial nitric oxide synthase (eNOS) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Chinese railway construction workers at Qinghai-Tibet where the altitude is over 4 500 m above sea level.</p><p><b>METHODS</b>A case-control study was conducted including 149 HAPE patients in the construction workers and 160 healthy controls randomly recruited from their co-workers, matching the patients in ethnicity, age, sex, lifestyle, and working conditions. Three polymorphisms of eNOS gene, T-786C in promoter, 894G/T in exon 7, and 27bp variable number tandem repeat (VNTR) in intron 4, were genotyped using polymerase chain reaction (PCR) and confirmed with DNA sequencing.</p><p><b>RESULTS</b>The frequencies of 894T allele and heterozygous G/T of the 894G/T variant were significantly higher in HAPE patients group than in the control group (P=0.0028 and P=0.0047, respectively). However, the frequencies of the T-786C in promoter and the 27bp VNTR in intron 4 were not significantly different between the two groups. Haplotypic analysis revealed that the frequencies of two haplotypes (H3,T-T-b, b indicates 5 repeats of 27 bp VNTR; H6, C-G-a, a indicates 4 repeats of 27 bp VNTR) were significantly higher in HAPE patients (both Pü0.0001). On the contrary, the frequencies of H1 (T-G-b) and H2 (T-G-a) were lower in HAPE patients than in healthy controls (both Pü0.001).</p><p><b>CONCLUSIONS</b>Two haplotypes (T-T-b and C-G-a) may be strongly associated with susceptibility to HAPE. Compared with the individual alleles of eNOS gene, the interaction of multiple genetic markers within a haplotype may be a major determinant for the susceptibility to HAPE.</p>

[Effect of alpha-zearalanol on the generation of reactive oxygen species (ROS) and ROS-activated signal transduction in tumor necrosis factor alpha-stimulated human endothelial cells].

OBJECTIVE: To investigate the effects of alpha-zearalanol (alpha-ZAL) on the generation of reactive oxygen species (ROS) and ROS-activated signal transduction in the tumor necrosis factor (TNF-alpha)-stimulated human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were cultured and divided into 4 groups: (1) normal control group, (2) TNF-alpha stimulated group, undergoing TNF-alpha stimulation for 24 h, (3) alpha-ZAL retreatment group, undergoing re-treatment with alpha-ZAL of the concentrations of 1 x 10(-8), 1 x 10(-7), or 1 x 10(-6) mol/L for 1 h, then stimulation of TNF-alpha for 24 h, and (4) plasmid transfection group, transfected with p47(phox) siRNA for 24 h to block the NADPH oxidase protein subunit p47(phox) in the HUVECs, or transfected with blank plasmid as control. The intracellular ROS production was detected by using 2, 7-dichlorofluorescin diacetate as probe. Semi-quantitative RT-PCR and immunocytochemistry were used to detect the mRNA and protein expression of p47(phox). The activation of extracellular signal-regulated kinase (ERK) and nuclear translocation of nuclear factor-kappaB (NF-kappaB), stimulatory protein (SP)-1, and activator protein (AP)-1 were assessed with Western blotting. RESULTS: The ROS level in the HUVECs of the TNF-alpha group was higher than that of the control group by 155.4%, and alpha-ZAL reduced the ROS level dose-dependently. TNF-alpha treatment up-regulated the p47(phox) mRNA expression by 212.8%, and obviously increased the p47(phox) protein expression; and alpha-ZAL pretreatment attenuated the TNF-alpha-induced p47(phox) mRNA expression by 63.0%, and also markedly inhibited the p47(phox) protein expression. No obvious ROS was found in the HUVECs stimulated by TNF-alpha after the transfection of p47(phox) siRNA. The ERK activation and nuclear translocation of transcription factors SP-1 and NF-kappaB induced by TNF-alpha were abolished or markedly inhibited by alpha-ZAL pretreatment. CONCLUSION: alpha-ZAL has a potent inhibitory effect on the ROS production and ROS-activated signaling pathway in the TNF-alpha stimulated endothelial cells, mainly through the inhibition of NADPH oxidase.

Inhibitory effects of alpha-zearalenol on angiotensin II-induced integrin beta3 mRNA via suppression of nuclear factor-kappaB.

OBJECTIVE: To investigate the effect of alpha-zearalenol on angiotensin II-induced beta3 integrin mRNA expression in human umbilical vein endothelial cells (HUVECs). METHODS: The mRNA level in integrin beta3 was determined by reverse transcription-polymerase chain reaction. Endothelial NF-kappaB activity was determined by the luciferase activity assay of plasmid NF-kappaB-LUC. RESULTS: The angiotensin II-induced beta3 integrin mRNA expression was inhibited by alpha-zearalenol and 17beta-estradiol (10 nmol/L -1 micromol/L), but not influenced by ICI 182, 780, a pure competitive antagonist for estrogen receptor or a nitric oxide inhibitor Nomega-Nitro-L-arginine methyl ester hydrochloride. Alpha-zearalenol and 17beta-estradiol suppressed the angiotensin II-induced activation of NF-kappaB in endothelial cells. CONCLUSION: Alpha-zearalenol inhibits angiotensin II-induced integrin beta3 mRNA expression by suppressing NF-kappaB activation in endothelial cells.

[mRNA expression of muscarinic receptors in spinal cord and brainstem in morphine dependent rats].

AIM: To observe mRNA expression of muscarinic acetylcholine receptors in spinal cord and brainstem in morphine dependent or withdrawal rats. METHODS: The mRNA expression level of m1, m2, m3, m4 and m5 were determined by RT-PCR, the beta-actin mRNA expression was used as internal control. RESULTS: The mRNA level of m1, m2, m3, m4 and m5 in spinal cord and m1 and m2 in brainstem were increased significantly during morphine dependence, and the levels of m1, m2, m3 and m4 in spinal cord and m1 in brainstem were decreased 1 h after the injection of naloxone (4 mg.kg-1, i.p.) in morphine dependent rats. Either scopolamine (0.5 mg.kg-1) or pirenzepine (10 mg.kg-1) was shown to significantly decrease the morphine withdrawal symptoms in rats. The levels of m1, m2, m3 and m5 in spinal cord were increased by pretreatment with pirenzepine and the levels of m2, m3 and m4 in spinal cord were increased by pretreatment with scopolamine. CONCLUSION: The adaptive expression of muscarinic receptors at spinal and supraspinal levels play important role in mediating morphine dependence and withdrawal in rats.