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Renal ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI) and even induces remote organ damage. Accumulating proofs demonstrates that the endocannabinoid system may provide a promising access for treatment strategy of renal IRI associated AKI. In the current study, using the established renal IRI model of rat, we tested the hypothesis that pretreatment of URB602, 30 min before renal IRI, alleviates kidney injury and relevant distant organ damage via limiting oxidative stress and inflammation. Using Western blot analysis and LC-MS/MS, renal IRI showed to increase the levels of 2-arachidonoylglycerol (2-AG) in kidneys as well as COX-2, PGE2, TXA2, and decrease N-arachidonoylethanolamine (anandamide, AEA); the expressions of renal cannabinoid receptor 1 (CB1) and cannabinoid receptor 2 (CB2) were unchanged. The URB602 pretreatment in renal IRI, further enhanced renal 2-AG which is high affinity to both CB1 and CB2, and reduced renal COX-2 which is involved in the regulation of renal perfusion and inflammation. AM630 (CB2 antagonist) almost blocked all the antioxidant, anti-inflammatory and nephroprotective effects of URB602, whereas AM251 (CB1 antagonist) showed limited influence, and parecoxib (COX-2 inhibitor) slightly ameliorated renal function at the dose of 10 mg/kg. Taken together, our data indicate that URB602 acts as a reactive oxygen species scavenger and anti-inflammatory media in renal IRI mainly depending on the activation of CB2.

Objectives Monoacylglycerol lipase participates in organ protection by regulating the hydrolysis of the endocannabinoid 2-arachidonoylglycerol. This study investigated whether blocking monoacylglycerol lipase protects against postresuscitation myocardial injury and improves survival in a rat model of cardiac arrest and cardiopulmonary resuscitation. Design Prospective randomized laboratory study. Setting University research laboratory. Subjects Male Sprague-Dawley rat (n = 96). Interventions Rats underwent 8-minute asphyxia-based cardiac arrest and resuscitation. Surviving rats were randomly divided into cardiopulmonary resuscitation + URB602 group, cardiopulmonary resuscitation group, and sham group. One minute after successful resuscitation, rats in the cardiopulmonary resuscitation + URB602 group received a single dose of URB602 (5 mg/kg), a small-molecule monoacylglycerol lipase inhibitor, whereas rats in the cardiopulmonary resuscitation group received an equivalent volume of vehicle solution. The sham rats underwent all of the procedures performed on rats in the cardiopulmonary resuscitation and cardiopulmonary resuscitation + URB602 groups minus cardiac arrest and asphyxia. Measurements and main results Survival was recorded 168 hours after the return of spontaneous circulation (n = 22 in each group). Compared with vehicle treatment (31.8%), URB602 treatment markedly improved survival (63.6%) 168 hours after cardiopulmonary resuscitation. Next, we used additional surviving rats to evaluate myocardial and mitochondrial injury 6 hours after return of spontaneous circulation, and we found that URB602 significantly reduced myocardial injury and prevented myocardial mitochondrial damage. In addition, URB602 attenuated the dysregulation of endocannabinoid and eicosanoid metabolism 6 hours after return of spontaneous circulation and prevented the acceleration of mitochondrial permeability transition 15 minutes after return of spontaneous circulation. Conclusions Monoacylglycerol lipase blockade may reduce myocardial and mitochondrial injury and significantly improve the resuscitation effect after cardiac arrest and cardiopulmonary resuscitation.

To reveal the radial growth trends of Pinus koraiensis and the differences in their responses to climate factors among different latitudes, and to assess the dynamic characteristics, adaptabi-lity and sensitivity of P. koraiensis under the influence of climate change, dendrochronological techniques were used to study the relationships between the climatic variables and the radial growth of P. koraiensis in broad-leaved Korean pine forests with different latitudes. The results showed that there were differences in the responses of the radial growth of P. koraiensis in four different latitudes to local climatic factors. In Baishilazi Nature Reserve, the southernmost sample plot, the radial growth of P. koraiensis was significantly positively correlated to the average relative humidity but significantly negatively correlated to the average maximum temperature of growing season. In low altitude of Changbai Mountain Nature Reserve, the intermediate sample plot, it was significantly positively correlated with precipitation, average relative humidity and PDSI, and significantly negatively correlated with the average maximum temperature in growing season. In Liangshui Nature Reserve, the intermediate sample plot, significantly positive correlations occurred for average relative humidity and PDSI in growing season, while significantly negative correlations occurred for the average temperature and the average maximum temperature in growing season. Nevertheless, in Shengshan Nature Reserve, the northernmost sample plot, it was positively correlated to the tempe-rature factors of most months. The climatic variables in June of current year were the main factors limiting the radial growth of P. koraiensis in all latitudes, and the average maximum temperature in June of current year was highly negatively correlated with radial growth for P. koraiensis measured at all sites. In recent four decades, with the rising of temperature, the radial growth of P. koraiensis decreased significantly in the southernmost point, increased significantly in the northernmost point, and did not change significantly in middle latitudes. The distribution area of P. koraiensis would be reduced if the temperature increased and precipitation remained unchanged in the future.运用树木年轮气候学方法,研究了不同纬度阔叶红松林红松径向生长趋势及其与气候因子的关系,以期揭示不同纬度红松径向生长对气候因子响应的差异以及气候变化影响下红松的动态特征、适应性及敏感性.结果表明: 不同纬度红松径向生长对当地气候因子的响应存在差异,最南部的白石砬子自然保护区红松径向生长与生长季的平均相对湿度呈显著正相关,与平均最高气温呈显著负相关.中部的长白山自然保护区的低海拔区域红松径向生长与生长季的水分因子(降水、相对湿度和帕尔默干旱指数PDSI)呈显著正相关,而与平均最高气温呈显著负相关;凉水自然保护区红松径向生长与生长季的水分因子(相对湿度和PDSI)呈显著正相关,与气温因子(平均气温和平均最高气温)呈显著负相关.而最北部的胜山自然保护区红松径向生长则与大部分月份的气温因子呈显著正相关.当年6月气候因子是影响所有纬度红松径向生长的关键气候因子,4个样地都与当年6月平均最高气温呈显著负相关.在气温不断上升的近40年,最南部的红松径向生长呈显著下降趋势,最北部呈显著上升趋势,中部的变化不显著.如果未来气温升高而降水不变,红松分布区可能缩小.

Background: We evaluated the effects and safety of an alternative technique for rapid sequence intubation in children predicting to have high risk of pulmonary aspiration in this prospective, randomized, placebo-controlled study. Methods: One hundred sixty-five children predicting to have high risk of pulmonary aspiration were randomly allocated to spontaneous breathing maintained induction and intubation group (Group S) and the modified rapid sequence group (Group C). The primary outcome was the incidence of hypoxemia around the intubation period, which was defined as SpO2

Dendrochronological techniques including correlation functions and single-years analysis were used to study the relationship between the two kinds of Korean pine radial growth in Liangshui Natural Reserve and climatic variables, and to assess the similarities and differences between Korean pine with coarse bark (Pinus koraiensis forma pachidermis) and fine bark (Pinus koraiensis forma leptodermis) in response to climate factors, the main affecting factors and whether the response relationship could be of long-term stability. The results showed that the Korean pine with fine bark was more suitable for dendrochronological study. The radial growth of the two kinds of Korean pine was very sensitive to environmental variables and their climate responses had no significant differ- ences. From 1902 to 2009, meteorological factors in the growing season, especially in June were the primary factors affecting the radial growth of the two kinds of Korean pine in the study area. The temperature showed a significant negative correlation and the precipitation showed a significant positive correlation. The Korean pine growing in different periods had a significantly different iresponse to meteorological factors. With the rapid rise of temperature and drought after 1970, the radial growth of the two kinds of Korean pine was more sensitive to the meteorological factors than before, which was especially more sensitive to temperature in growing season and PDSI in many seasons.