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Objective To observe the injury of intestinal mucosal barrier and the expression of autophagy protein in colon tissue of rats with chronic renal failure. Methods Thirty SPF healthy male SD rats were randomly divided into sham operation group (10 rats) and model group (20 rats). The model group was given adenine 200 mg/(kg·d) by gavage for 4 weeks after left nephrectomy. The general conditions of rats were observed. Serum, renal tissue and colon tissue samples were collected at 4 and 8 weeks after gavage. The levels of serum creatinine, urea nitrogen, TNF-α, IL-6 and LPS were measured by ELISA. Renal and colon tissue were examined by HE staining and microscopy. The protein expressions of LC3, beclin-1, ZO-1 and claudin-1 were detected by Western blot. Results Compared with the sham operation group, the model group rats gradually showed a slow response to external stimuli, slow action, withered and yellow hair color, dull luster, pale conjunctiva and slow weight gain. The levels of serum creatinine, urea nitrogen and inflammatory factors in the model group were all higher than those in the sham operation group, and increased at 8 weeks compared with 4 weeks (P＜0.05). Renal pathology in the model group showed renal tubular dilatation, lymphatic and monocyte infiltration, glomerulosclerosis and interstitial fibrosis. Histopathology of colon in model group showed atrophy and collapse of intestinal villi, infiltration of inflammatory cells in mucosal layer and aggravation of pathological changes, which was more serious at 8 weeks than at 4 weeks. The expression of LC3Ⅱ/Ⅰ, Beclin-1, ZO-1 and Claudin-1 in the model group decreased as compared to those of sham operation group(P＜0.05), and much decreased at 8 weeks as compared with 4 weeks (P＜0.05). Conclusions Autophagy disorder may be a potential mechanism causing intestinal mucosal barrier injury in rats with chronic renal failure.

Time-frequency electromagnetic method (TFEM), characterized by strong excitation signal, large detection depth and high precision, is one of the most promising techniques for the fine identification of igneous rock reservoirs and surface oil-gas detection, which can determine the oil-gas content by detecting the electrical and electrochemical anomalies of oil-gas reservoirs. Through analyzing the electrical logging data of HX sag in Iiaohe Basin, it is confirmed that TFEM has the physical basis to identify different igneous rocks. The fault structure characteristics as well as the igneous rock inner structures of Shahejie Formation are obtained by the well seismic-TFEM joint inversion, and 5 stages of volcanic activities within the third member of Shahejie Formation are identified. A set of classification standard for polarizability evaluation is summarized through the extraction of amplitude and phase anomalies related to resistivity and polarizability, and comparison of oil production condition of the known wells. Combined with the seismic data, the oil-gas migration mechanism in HX sag is reversed by TFEM. The oil-gas evaluation template in the area is obtained through the research, by which several oil-gas favorable areas are identified and verified by subsequent drilling work. The method can provide reference for oil-gas evaluation in similar areas. [ABSTRACT FROM AUTHOR]

Chronic pain hypersensitivity depends on N-methyl-D-aspartate receptors (NMDARs). However, clinical use of NMDAR blockers is limited by side effects resulting from suppression of the physiological functions of these receptors. Here we report a means to suppress pain hypersensitivity without blocking NMDARs, but rather by inhibiting the binding of a key enhancer of NMDAR function, the protein tyrosine kinase Src. We show that a peptide consisting of amino acids 40-49 of Src fused to the protein transduction domain of the HIV Tat protein (Src40-49Tat) prevented pain behaviors induced by intraplantar formalin and reversed pain hypersensitivity produced by intraplantar injection of complete Freund's adjuvant or by peripheral nerve injury. Src40-49Tat had no effect on basal sensory thresholds, acute nociceptive responses or cardiovascular, respiratory, locomotor or cognitive functions. Thus, through targeting of Src-mediated enhancement of NMDARs, inflammatory and neuropathic pain are suppressed without the deleterious consequences of directly blocking NMDARs, an approach that may be of broad relevance to managing chronic pain., Chronic pain is categorized as inflammatory or neuropathic, each involving neuroplastic changes leading to hypersensitivity in peripheral and central nociceptive systems (1,2). Multiple mechanisms including increased primary afferent excitability (3), [...]

Time-frequency electromagnetic method (TFEM), as a relatively mature oil and gas detection technology, has been widely used both in China and overseas. In the process of time-frequency electromagnetic interpretation, the combined qualitative detection of resistivity and polarizability is commonly used. However, such method cannot quantitatively evaluate the oil and gas content, and regards the formation resistivity as a quantity independent of temperature and pressure. In fact, with the increase of formation depth, the temperature and pressure changes of the formation will affect the resistivity, which would cause errors to reservoir interpretation. This paper analyzes the variation law of rock electrical parameters with frequency through the frequency dispersion test of rock. Combined with the dispersion properties of rock, the variation characteristics of formation resistivity affected by temperature and pressure are studied, and then the approximate relationship between rock resistivity and temperature/pressure is obtained by fitting. Using appropriate temperature-pressure-resistivity function, the time-frequency electromagnetic reservoir data are corrected for resistivity, by which the saturation of the target reservoir in the study area is calculated with the Archie formula, and the reservoir is quantitatively evaluated. [ABSTRACT FROM AUTHOR]