AIM: To evaluate the role of intestinal endotoxemia in the genesis of hepatopulmonary syndrome. METHODS: A rat model of cirrhosis was prepared with the method of compound factors. At the end of the eighth week, rats w...AIM: To evaluate the role of intestinal endotoxemia in the genesis of hepatopulmonary syndrome. METHODS: A rat model of cirrhosis was prepared with the method of compound factors. At the end of the eighth week, rats with cirrhosis were treated with 300 μg LPS/100 g body weight, and 1 g/rat of glycine about four h prior to LPS. After three h of LPS treatment, blood and tissues were collected for various measurements. Kupffer cells were isolated from male Wistar rats and cultured, and divided into five groups. Supernatant was harvested at 3 h after treatment with LPS for measurement of tumor necrosis factor-alpha (TNF-α). RESULTS: Our results showed that in rats with cirrhosis, slowed and deepened breath with occasional pause was. PaO2, PaCO2 and standard bicarbonate (SB) in arterial blood were decreased. Arterial O2 and actual bicarbonate (AB) were markedly decreased. There was a close correlation between decreased O2 and endotoxin. Metabolic acidosis accompanying respiratory alkalosis was the primary type of acid-base imbalance. The alveolar-arterial oxygen gradient was sharply widened. Massive accumulation of giant macrophages in the alveolar spaces and its wall and widened alveolar wall architecture were observed. The number of bacterial translocations in mesenteric lymph nodes increased. The ratio of TC99M-MAA brain-over-lung radioactivity rose. Endotoxin, and TNF-α, endothelin-1 (ET-1), nitric oxide (NO) in plasma and ET-1, carbon monoxide (CO) in lung homogenates increased. After administration of a given dosage of LPS in rats with cirrhosis, various pathological parameters worsened. Plasma level of endotoxin was related to TNF-α, ET-1, NO in plasma and ET-1, NO, CO in lung homogenates. TNF-α level was related to ET-1 and NO in plasma and lung homogenates and CO in lung homogenate as well. The level of TNF-α increased after infusion of LPS into culture supernatant of Kupffer cells in vitro. However, TNF-α significantly decreased after pretreatment with glycine, PD98059 and SB212850. Glycine could anta展开更多
We report the experimental observations of the segregation patterns in initially well mixed copper and glass spheres subjected to a vertical sinusoidal vibration at differ-ent values of acceleration G and frequency f....We report the experimental observations of the segregation patterns in initially well mixed copper and glass spheres subjected to a vertical sinusoidal vibration at differ-ent values of acceleration G and frequency f. A segregation phase diagram is obtained, which includes Brazil nut (BN), Reversed-BN (RBN) and sandwich segregation patterns at different G and f. The stable RBN segregation is experimen-tally found for the first time, in which large heavy particles move down to the bottom and form the lower-layer while small particles rise to the top and form an upper-layer. The boundary values (G, f), which separate regions of different patterns, depend on system’s initial condition, i.e. hysteresis exists.展开更多
文摘AIM: To evaluate the role of intestinal endotoxemia in the genesis of hepatopulmonary syndrome. METHODS: A rat model of cirrhosis was prepared with the method of compound factors. At the end of the eighth week, rats with cirrhosis were treated with 300 μg LPS/100 g body weight, and 1 g/rat of glycine about four h prior to LPS. After three h of LPS treatment, blood and tissues were collected for various measurements. Kupffer cells were isolated from male Wistar rats and cultured, and divided into five groups. Supernatant was harvested at 3 h after treatment with LPS for measurement of tumor necrosis factor-alpha (TNF-α). RESULTS: Our results showed that in rats with cirrhosis, slowed and deepened breath with occasional pause was. PaO2, PaCO2 and standard bicarbonate (SB) in arterial blood were decreased. Arterial O2 and actual bicarbonate (AB) were markedly decreased. There was a close correlation between decreased O2 and endotoxin. Metabolic acidosis accompanying respiratory alkalosis was the primary type of acid-base imbalance. The alveolar-arterial oxygen gradient was sharply widened. Massive accumulation of giant macrophages in the alveolar spaces and its wall and widened alveolar wall architecture were observed. The number of bacterial translocations in mesenteric lymph nodes increased. The ratio of TC99M-MAA brain-over-lung radioactivity rose. Endotoxin, and TNF-α, endothelin-1 (ET-1), nitric oxide (NO) in plasma and ET-1, carbon monoxide (CO) in lung homogenates increased. After administration of a given dosage of LPS in rats with cirrhosis, various pathological parameters worsened. Plasma level of endotoxin was related to TNF-α, ET-1, NO in plasma and ET-1, NO, CO in lung homogenates. TNF-α level was related to ET-1 and NO in plasma and lung homogenates and CO in lung homogenate as well. The level of TNF-α increased after infusion of LPS into culture supernatant of Kupffer cells in vitro. However, TNF-α significantly decreased after pretreatment with glycine, PD98059 and SB212850. Glycine could anta
基金supported by the National Key Program for Basic Research(Grant No.R39799N)the National Natural Science Foundation of China.
文摘We report the experimental observations of the segregation patterns in initially well mixed copper and glass spheres subjected to a vertical sinusoidal vibration at differ-ent values of acceleration G and frequency f. A segregation phase diagram is obtained, which includes Brazil nut (BN), Reversed-BN (RBN) and sandwich segregation patterns at different G and f. The stable RBN segregation is experimen-tally found for the first time, in which large heavy particles move down to the bottom and form the lower-layer while small particles rise to the top and form an upper-layer. The boundary values (G, f), which separate regions of different patterns, depend on system’s initial condition, i.e. hysteresis exists.
