[Long-term Changes and Drivers of Ecological Security in Shahe Reservoir, China].

Monthly datasets of ecological indicators from 2010 to 2020 in Shahe Reservoir, Tianmuhu, China, were examined to reveal the long-term variations in water ecological security and its driving factors. The results of Secchi disk depth(SD) measurements revealed significantly spatial variation(P<0.05) within the reservoir. The highest SD was recorded in the downstream-linked reservoir, and the lowest SD was recorded in the upstream tributaries. In contrast, the values of other water ecological indicators were higher in the upstream tributaries than in the transition region and the downstream-linked reservoir area. In summer and autumn, the SD was low, while the concentrations of total phosphorous(TP), chlorophyll a(Chl-a), the permanganate index, and cyanobacterial biomass(BMc) were high. During the thermal stratification period from May to September, the concentrations of 2-methylisoborneol(MIB) and Chl-a were highest at a depth of 4 m, while diatom biomass(BMb) and BMc reached their maximum at depths of 2 m and 0.5 m, respectively. Therefore, spatial and temporal variations should be fully considered when evaluating aquatic ecological security. Focusing on spring and summer, when the risk of water ecological security was high, Chl-a combined with SD and MIB along with their correlation with other water quality indexes, was used to evaluate and optimize the ecological security of Shahe Reservoir. The evaluation results showed that the aquatic ecological security of the reservoir was excellent over the last 10 years; however, annual fluctuations have been large and the evaluation scores were spatially variable. While seasonal sampling strategies focusing on three layers depths are economical and reliable for lake regions with thermal stratification, our results indicate that tailored monitoring may be required to determine the aquatic ecological security of lakes and reservoirs. In Shahe Reservoir, the decrease in the SD and the increase in MIB caused by high TP and algal blooms were the most important drivers of ecological service function in the reservoir. Furthermore, hydrometeorological factors may also play important roles in the aquatic ecological security of reservoirs.

[Effect of Electroacupuncture Stimulation of Heart and Lung Meridians on Expression of Myocardial HCN 2 in Acute Myocardial Ischemia Rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) stimulation of Heart and Lung meridians on the expression of hyperpolarization-activated cyclic nucleotide gated potassium channel 2 (HCN 2) mRNA and protein in the myocar-dium of the left ventricle in acute myocardial ischemia (AMI) rats, so as to underlying its mechanism in improving ischemic myocardial injury. METHODS: A total of 120 male SD rats were randomly divided into normal control, model, EA-Heart Meridian (HT) and EA-Lung Meridian (LU) groups (n＝30 rats in each group). The AMI model was established by occlusion of the anterior descending branch of coronary artery. EA (1 mA, 10 Hz) was applied to bilateral "Shenmen" (HT 7) or "Taiyuan" (LU 9) and the spot about 1 mm apart from the HT 7 or LU 9 on the axopetal end for 15 min on the second day after modeling, once a day for 7 days. The left ventricular myocardium tissue was sampled for determining the expression levels of HCN 2 mRNA and protein with qPCR and Western blot, separately. RESULTS: After AMI, both HCN 2 mRNA and protein expression levels in the model group were significantly decreased in comparison with the normal control group (P<0.01). Following EA intervention, the expression levels of HCN 2 mRNA and protein expressions were significantly up-regulated relevant to the model group (P<0.01)．The effects were more obvious in the EA-HT group than in the EA-LU group, and the expression levels were higher in the left ventricular myocardium tissue sampled on the next day after the treatment than those in the tissue sampled immediately after the treatment (P<0.01). CONCLUSION: Both EA stimulation of Heart Meridian and Lung Meridian can improve the expression of HCN 2 mRNA and protein in the myocardium in AMI rats, which existing a delayed effect and meridian specificity.

[Effect of Different Concentrations of Moxa-smoke on Lung Function and TNF-α and IL-1 ß Levels in Serum and Lung Tissues in Normal Rats].

OBJECTIVE: To study the effect of moxa-smoke inhaling on the respiratory system, so as to provide experimental data and theoretical basis for evaluating the safety of moxa-smoke inhaling during moxibustion treatment. METHODS: A total of 48 SD rats were randomized into control, low, medium and high moxa-smoke-concentration groups (n＝12 in each group). The low, medium and high concentrations of smoke were controlled in (0.11±0.05) mg/m3, (0.23±0.05) mg/m3 and (0.53±0.05) mg/m3 respectively in each of 3 glass boxes (with reference to the level of PM 2.5). The smoking was conducted 4 hours each time, twice a day for 100 days. The normal group did not receive any moxa-smoke inhaling. The histopathological changes of lung and bronchial tissues were detected by H．E. stainning, and the contents of TNF-α and IL-1 ß of plasma, bronchoalveolar la-vage fluid (BALF) and lung tissue detected by ELISA. The levels of forced vital capacity (FVC), forced expiratory volume (FEV), FEV 0.3/FVC (0.3＝ the 0.3rd second), maximal mid-expiratory flow rate(MMEF), peak expiratory flow(PEF) were detected by animal pulmonary function analysis system. RESULTS: After 100 days' moxa-smoke inhaling, the contents of TNF-α in the plasma, BALF and lung tissues and IL-1 ß in the lung tissue of the low, medium and high concentration moxa-smoke groups, and IL-1 ß in the plasma and BALF of the medium and high concentration groups were significantly increased relevant to the control group (P<0.05, P<0.01). H．E. stain showed various inflammatory changes in the lungs and trachea tissues, including obvious fusion of pulmonary alveoli, lymphocyte infiltration, increase of capillary permeability, red blood cell exudation, etc. in the high concentration group, these situations were milder in the medium concentration group and were not obvious in the low concentration group. Compared with the control group, there were no significant changes in the FVC, FEV, FEV 0.3/FVC, MMEF and PEF of lung function in the three concentration groups (P> 0.05)．. CONCLUSION: Long term inhalation of high concentration of moxa-smoke may lead to inflammatory injury in the lung and bronchial tissues but has no significant effect on the respiratory function in rats. Nevertheless, a good air-ventilation during moxibustion in a treatment room is necessary.