Removal of nitrogen, phosphorus, and organic pollutants from water using seeding type immobilized microorganisms

Objective To study the possibility of removing nitrogen, phosphorus, and organic pollutants using seeding type immobilized microorganisms. Methods Lakes P and M in Wuhan were chosen as the objects to study the removal of nitrogen, phosphorus, and organic pollutants with the seeding type immobilized microorganisms. Correlations between the quantity of heterotrophic bacteria and the total nitrogen （TN）, total phosphorus （TP）, and total organic carbon （TOC） in the two lakes were studied. The dominant bacteria were detected, inoculated to the sludge and acclimated by increasing nitrogen, phosphorus and decreasing carbon source in an intermittent, time-controlled and fixed-quantity way. The bacteria were then used to prepare the seeding type immobilized microorganisms, selecting diatomite as the adsorbent cartier. The ability and influence factors of removing nitrogen, phosphorus, and organic pollutant from water samples by the seeding type immobilized microorganisms were studied. Results The coefficients of the heterotrophic bacterial quantity correlated with TOC, TP, and TN were 0.9143, 0.8229, 0.7954 in Lake P and 0.9168, 0.7187, 0.6022 in Lake M. Ten strains of dominant heterotrophic bacteria belonging to Pseudomonas, Coccus, Aeromonas, Bacillus, and Enterobateriaceae, separately, were isolated. The appropriate conditions for the seeding type immobilized microorgansims in purifying the water sample were exposure time=24 h, pH=7.0-8.0, and quantity of the immobilized microorganisms=0.75-1g/50 mL. The removal rates of TOC, TP, and TN under the above conditions were 80.2%, 81.6%, and 86.8%, respectively. Conclusion The amount of heterotrophic bacteria in the two lakes was correlated with TOC, TP, and TN. These bacteria could be acclimatized and prepared for the immobilized microorganisms which could effectively remove nitrogen, phosphorus, and mixed organic pollutants in the water sample.     

环维黄杨星D的结构修饰及耐缺氧活性的研究

目的 以环维黄杨星D为先导化合物进行结构修饰,以寻求更好的耐缺氧活性的衍生物.方法 将能改变药物活性和水溶性的含氮杂环化合物用于环维黄杨星D的结构修饰,合成目标化合物Ⅱa～Ⅱg.结果 合成了7个未见报道的环维黄杨星D衍生物,其结构经1 HNMR、”CNMR、MS和IR表征;同时进行了小鼠耐缺氧活性的研究.结论 合成的新化合物具有一定的生物活性,其中,含吗啉基、咪唑基、哌嗪基取代的衍生物具有较好的生物活性.     

Chronic Alcohol Administration Stimulates Nitric Oxide Formation in the Rat Liver With or Without Pretreatment by Lipopolysaccharide

This study examines the effect of chronic alcohol consumption on nitric oxide release from the liver of rats with or without lipopolysaccharide (LPS) (Escherichia coli) treatment. Reactive nitrogen intermediates (RNIs) in plasma were monitored with an NO_x Analyzer, and nitric oxide (NO) production was measured as nitrite or nitrite + nitrate accumulation in perfusates of the perfused liver, and in supematants of the freshly isolated hepatic cells after incubation for 3 hr in Hank's balanced salt solution buffer containing 1 Mm l -arginine. RNI concentration in plasma of control rats was 32.0 ± 3.4 μm (mean ×se ). Livers from diet-fed control rats produced RNIs at the barely detectable rate of 7.8 ± 1.5 nmol/hr × g wet liver. Six hr after administration of LPS (1 mg/kg, iv), plasma RNI levels in diet-fed control rats increased to 426.9 ± 29.4 μm , and RNI release from the perfused liver was also markedly elevated to 97.7 ± 7.7 nmol/hr × wet g liver, indicating hepatic NO release as a potentially important source for the increased RNI in plasma. The presence of N^G-monomethyl-l -arginine (0.5–1 mm ) or the absence of l -arginine in the perfusate inhibited LPS-induced stimulation of RNI release. EGTA (1 mm ) had little effect, indicating that the increased RNI release was likely to be due to inducible NO synthase activity. The release of RNIs by freshly isolated Kupffer cells increased 13-fold, and this small cell mass contributed almost half of the hepatic RNI production under these conditions. Plasma ALT concentration was elevated after LPS administration, indicating incipient liver damage. Chronic alcohol administration resulted in increased RNI levels in plasma (44.6 ± 4.2) that were accompanied by increased spontaneous release in the perfused liver (16.4 ± 1.5 nmol/hr wet g). Enhanced activity of Kupffer cells was responsible for this increase. After administration of LPS, the increase in plasma RNIs (565.72 ± 49.6 μm ) was slightly higher in chronic alcoholic rats than in control animals. This was also accompanied by a somewhat higher RNI release from the perfused liver (125.40 ± 12.2 nmol/hr × wet g) in the same group. Hepatocytes were responsible for the post-LPS increase in alcoholic rats. Plasma ALT concentration was higher in alcoholic than control, diet-fed rats after LPS, indicating more liver damage in that group. The exact role of the elevated hepatic RNI release in affecting hepatic function in chronic alcoholic animals remains to be clarified.     

Effect of 0.25 ppm nitrogen dioxide on the airway response to methacholine in asymptomatic asthmatic patients

In asthmatic patients, short-term exposure to nitrogen dioxide at low concentrations has been reported to result in a nonuniform airway response to various bronchoconstrictive stimuli. We therefore investigated in 11 patients with mild and stable asthma with normal baseline airway tone the effect of 0.25 ppm nitrogen dioxide on the airway response to methacholine. On 2 separate days, the subjects inhaled either 0.25 ppm nitrogen dioxide or filtered air (sham) during 20 min of tidal breathing followed by 10 min of bicycle exercise at room temperature (mean exercise ventilation 30 L/min). Methacholine inhalation tests were performed 1 h after the end of exercise to determine the methacholine concentration necessary to increase SRaw by 100% (PC₁₀₀SRaw). On a third day, a methacholine challenge was done without previous exposure (control). Mean (SEM) exercise-induced increase of SRaw was 80 (24) % after sham and 82 (25) % after nitrogen dioxide, which was not significantly different (p>0.10). PC₁₀₀SRaw did not differ on the 3 occasions, geometric mean values (variability of mean) being 0.41 (1.6), 0.41 (1.6), and 0.46 (1.5) mg/ml after sham, nitrogen dioxide, and control, respectively (p<0.10). We therefore conclude that in patients with mild and stable asthma short-term exposure to 0.25 ppm nitrogen dioxide during rest and exercise does not increase methacholine responsiveness 1 h after exposure.     

视网膜光凝治疗 Eales 病前后一氧化氮与一氧化氮合酶的检测分析

目的：观察Eales病患者视网膜光凝治疗前后血浆一氧化氮（NO ）水平及一氧化氮合酶（NOS ）的活性。方法选择沧州市中心医院眼科2006年5月至2013年7月经临床确诊的Eales病患者104例（170眼）为观察组,按照眼底荧光血管造影结果,将观察组分为激光治疗患者60例（78眼）,非激光治疗患者44例（92眼）。选择同期健康人群66例为健康对照组。对所有研究对象术前术后分别检测NO、NOS。结果观察组NO、总NOS及结构型NOS（cNOS）活性平均值低于健康对照组（P＜0．05）。激光治疗和非激光治疗患者各指标比较,差异均无统计学意义（P＞0．05）。激光治疗患者术前及术后NO、NOS比较,差异无统计学意义（P＞0．05）。激光治疗患者中视力保持稳定或提高者共70眼（89．74％）。结论 NO与NOS可能参与 Eales病的发生发展,视网膜光凝治疗能有效控制Eales病的发展,但视网膜光凝治疗未能从根本上治疗Eales病。     

妊高征患者血清尿素氮、肌酐和尿酸水平的变化

目的 通过测定妊娠高血压综合征孕妇血清尿素氮、肌酐和尿酸水平，探讨其临床意义。方法 采用生化分析仪测定50例妊娠高血压综合征孕妇（实验组）与43例正常妊娠的孕妇（对照组）血清尿素氮、肌酐和尿酸水平。结果 实验组血清尿素氮、肌酐浓度均高于对照组（P〈0．01）；血清中尿酸水平也显著增高（P〈0．005），血清尿素氮、肌酐、尿酸水平随着病情加重，均有升高趋势（P〈0．01）。结论 测定妊娠高血压综合征孕妇血清尿素氮、肌酐和尿酸对了解病情严重程度有一定的临床意义。     

Assessment of functional residual capacity using nitrogen washout and plethysmographic techniques in infants with and without bronchopulmonary dysplasia

Objective: In normal infants, functional residual capacity using plethysmography (FRC_pleth) exceeds FRC_N2 (using nitrogen washout) and the within-subject difference FRC_(pleth−N2) indicates the part of pulmonary gas volume not ventilated during tidal breathing. We postulated that infants with bronchopulmonary dysplasia (BPD) have an elevated FRC_(pleth−N2). Design: In a prospective study, FRC_(pleth−N2) in healthy newborns (controls n = 17) was compared to that in neonates recovering from the respiratory distress syndrome without BPD (noBPD, studied at discharge, n = 13) and with BPD (BPD1 n = 14, studied at 36 post-conceptional weeks; BPD2 n = 16, at discharge). Measurements and results: Paired measurements, FRC_pleth and FRC_N2, were performed using a plethysmograph (Jaeger, Germany) and an open-circuit nitrogen washout technique (SensorMedics 2600, USA). In comparison to the controls (5.2 ml/kg), FRC_(pleth−N2)/kg in noBPD (12.7 ml/kg, p < 0.001), in BPD1 (24.9 ml/kg, p < 0.001) and in BPD2 (13.5 ml/kg, p < 0.001) was significantly higher. Compared with that of the controls FRC_pleth was significantly increased in BPD1 (p < 0.001) and FRC_N2 was decreased in noBPD and both BPD groups. Conclusion: The FRC_(pleth−N2) is a reliable indicator for pulmonary inhomogeneities in infants with respiratory diseases. Received: 15 July 1997 Accepted: 26 January 1998     

吸入偏二甲基肼和四氧化二氮引起急性肺损伤及氧化过氧化在其发生机制中的作用

目的　研究吸入大剂量火箭液体推进剂偏二甲基肼 (UDMH)和四氧化二氮 (N2 O4)引起急性肺损伤 (ALI)的表现以及抗氧化系统酶与过氧化损伤在其中的作用。方法　静式染毒柜中UDMH和N2 O4浓度分别为 4 0 0ppm和 5 0ppm。受实验大鼠自主呼吸 ,染毒时间均为 10min ,在毒物暴露前及暴露后的 2、6、12、2 4、4 8h分别处死 14只动物。测定大鼠肺组织湿 /干重比 (W /D)、支气管肺泡灌洗液 (BALF)总蛋白和乳酸脱氢酶 (LDH)等肺损伤指标以及肺组织超氧化物歧化酶 (SOD)、谷胱甘肽过氧化物酶 (GSH -Px)、丙二醛 (MDA)和血浆MDA等抗氧化系统酶和脂质过氧化指标。观察动物一般情况及组织病理学变化。结果　大剂量UDMH和N2 O4吸入后 ,肺组织W/D、BALF蛋白和LDH均有不同程度增加 ;肺组织SOD、GSH -Px和MDA等有不同程度降低 ,血浆MDA明显升高。其峰值多出现在吸入后 6～ 12h。肺组织W/D与肺组织SOD和GSH -Px活性之间均有显著的负相关 ,相关系数r分别等于 - 0 .6 0 4 (P <0 .0 1)和 - 0 .6 4 9(P <0 .0 1)。结论　大剂量UDMH和N2 O4吸入可引起ALI,其原因可能与该物质破坏机体的抗氧化系统酶 ,造成机体过氧化损伤有关。     

2013~2015年济南市大气污染物SO2和NO2对居民心血管疾病应急呼叫事件影响的急性效应

目的 定量分析济南市大气污染物SO₂和NO₂对居民心血管疾病应急呼叫事件的急性影响。 方法 描述性分析2013~2015年济南市逐日气象、空气污染物和居民心血管疾病应急呼叫事件资料。采用基于Quasi-Poisson回归的广义相加模型分别进行SO₂、NO₂与逐日居民心血管疾病应急呼叫事件的单污染物模型、滞后效应(lag1~lag7)和累积滞后效应(lag01~lag07)分析。计算污染物浓度每升高10 μg/m³,居民心血管疾病应急呼叫事件风险增加的超额危险度及95%置信区间(95%CI)。 结果 2013~2015年济南市逐日SO₂、NO₂浓度水平及居民心血管疾病应急呼叫事件数的均值分别为73 μg/m³、55 μg/m³及17人。SO₂、NO₂浓度每升高10 μg/m³,当日(lag0)居民心血管疾病应急呼叫事件风险可分别增加0.41%(95%CI:0.10%~0.72%)和0.99%(95%CI:0.27%~1.71%),同时存在显著的累积滞后效应。 结论 济南市大气污染物SO₂、NO₂均对居民心血管疾病应急呼叫事件风险存在急性效应。