Effects of bulking agent addition on odorous compounds emissions during composting of OFMSW.

The effects of rice straw addition level on odorous compounds emissions in a pilot-scale organic fraction of municipal solid waste (OFMSW) composting plant were investigated. The cumulative odorous compounds emissions occurred in a descending order of 40.22, 28.71 and 27.83 mg/dry kg of OFMSW for piles with rice straw addition level at ratio of 1:10, 2:10 and 3:10 (mixing ratio of rice straw to OFMSW on a wet basis), respectively. The mixing ratio of rice straw to OFMSW had a statistically significant effect on the reduction of malodorous sulfur compounds emissions, which had no statistically significant effect on the reduction of VFAs, alcohols, aldehydes, ketones, aromatics and ammonia emissions during composting, respectively. The cumulative emissions of malodorous sulfur compounds from piles with the increasing rice straw addition level were 1.17, 1.08 and 0.88 mg/dry kg of OFMSW, respectively. The optimal mixing ratio of rice straw to OFMSW was 1:5. Using this addition level, the cumulative malodorous sulfur compounds emissions based on the organic matter degradation were the lowest during composting of OFMSW.

Hydrogen sulfide donor regulates alveolar epithelial cell apoptosis in rats with acute lung injury.

BACKGROUND: Acute lung injury (ALI) is a common syndrome associated with high morbidity and mortality in emergency medicine. Cell apoptosis plays a key role in the pathogenesis of ALI. Hydrogen sulfide (H(2)S) plays a protective role during acute lung injury. We designed this study to examine the role of H(2)S in the lung alveolar epithelial cell apoptosis in rats with ALI. METHODS: Sixty-nine male Sprague Dawley rats were used. ALI was induced by intra-tail vein injection of oleic acid (OA). NaHS solution was injected intraperitonally 30 minutes before OA injection as the NaHS pretreatment group. Single sodium hydrosulfide pretreatment group and control group were designed. Index of quantitative assessment (IQA), wet/dry weight (W/D) ratio and the percentage of polymorphonuclear leukocyte (PMN) cells in the bronchoalveolar lavage fluid (BALF) were determined. H(2)S level in lung tissue was measured by a sensitive sulphur electrode. Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and Fas protein was measured by immunohistochemical staining. RESULTS: The level of endogenous H(2)S in lung tissue decreased with the development of ALI induced by OA injection. Apoptosis and Fas protein in alveolar epithelial cells increased in the ALI of rats but NaHS lessened apoptosis and Fas protein expression in alveolar epithelial cells of rats with ALI. CONCLUSION: Endogenous H(2)S protects rats from oleic acid-induced ALI, probably by inhibiting cell apoptosis.

[Effects of hydrogen sulfide on the expressions of nuclear factor-κB and intercellular adhesion molecule 1 in pulmonary tissue of rats with acute lung injury].

OBJECTIVE: To explore the potential effects of hydrogen sulfide (H(2)S) on nuclear factor kappa B (NF-κB) and intercellular adhesion molecule 1 (ICAM-1) in lung tissue with oleic acid (OA)-induced acute lung injury (ALI) in rats. METHODS: Forty-two rats were randomly divided into 3 groups: control (n = 6), OA (n = 18) and OA + NaHS (n = 18). Rats in the OA group received an intra-tail vein injection of oleic acid 0.1 ml/kg while those in the OA + NaHS group an intraperitoneal injection of NaHS 56 µmol/kg at 30 mins before OA injection. The OA and OA + NaHS groups were subdivided into 3 subgroups depending on the therapeutic duration: 2 h (n = 6), 4 h (n = 6) and 6 h (n = 6). Rats in the control group received an intra-tail vein injection of normal saline 0.1 ml/kg. Bronchioalveolar lavage fluid (BALF) was collected and the leucocytic differential count of sediment examined. The extent of lung injury was evaluated by the index of quantitative assessment (IQA). The H(2)S level in lung tissue was measured by sensitive sulphur electrode. The nuclear translocation of NF-κB and the expression of ICAM-1 in alveolar epithelial cells were measured by immunohistochemical staining. RESULTS: Compared with the control group, the BALF percentage of polymorphonuclear (PMN) cell was significantly higher at 2, 4 and 6 h in the OA-treated rats [(74.5 ± 3.0)%, (80.2 ± 2.0)%, (87.2 ± 2.7)% vs (3.1 ± 1.6)%, all P < 0.01]. And the value of IQA increased significantly versus those at 2, 4 and 6 h in the control group (5.2 ± 0.8, 6.4 ± 0.6, 6.8 ± 0.8 vs 0.4 ± 0.6, all P < 0.01). And the levels of H(2)S in lung tissue decreased at 2, 4 and 6 h [(21.20 ± 0.38) µmol/g, (20.80 ± 0.53) µmol/g, (18.92 ± 0.75) µmol/g vs (26.81 ± 0.65) µmol/g, all P < 0.01]. Moreover, the nuclear expression of NF-κB and the membranous expression of ICAM-1 in the alveolar epithelial cells in OA group rats was significantly higher than those of the control group (all P < 0.05). After the dosing of H(2)S donor (NaHS), the BALF percentage of PMN cell and the lung IQA decreased in the three subgroup rats (2, 4 and 6 h) versus the OA group. And the concentration of H(2)S increased significantly in the 4 h and 6 h subgroups versus the OA group at the corresponding time points. Simultaneously, the nuclear expression of NF-κB and the membranous expression of ICAM-1 in alveolar epithelial cells were significantly lower than that of the OA group at 4 h and 6 h subgroups (all P < 0.05). CONCLUSION: H(2)S may play a protective role in the ALI rats through the suppression of lung inflammation. And the inhibited expression of alveolar epithelial cell NF-κB mediates the anti-inflammatory effects of H(2)S.

[Prognostic factors for patients with pulmonary thromboembolism after orthopaedic surgery].

OBJECTIVE: To investigate the changes of serum enzymes and their prognostic value in patients with pulmonary thromboembolism after orthopaedic surgery. METHODS: Clinical data of 134 cases of confirmed pulmonary thromboembolism after orthopaedic surgery from 1997 to 2010 were reviewed.The 134 cases were divided into dead group (n=28) and survival group (n=106). The clinical presentation, electrocardiogram, arterial oxygen pressure (PaO2), chest X-ray, echocardiography,and serum enzymes including alanine transaminase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (γ-GT), lactate dehydrogenase (LDH), creatine kinase (CK) and creatine kinase isoenzyme (CK-MB) were analyzed. And multivariable Logistic regression was conducted to identify the risk factors of in-hospital death. RESULTS: The average age of dead patients was higher than that of survival patients (P=0.043), while the P(O2) of dead patients was much lower than that of survival patients (P=0.035). The percentage of syncope, hypotension, right bundle-branch block and SIQIIITIII, pulmonary hypertension and right ventricular dysfunction in dead patients were higher than those in survival patients (P=0.009, P=0.041, P=0.018, P=0.030, P=0.042 and P=0.038), respectively. There were significant differences of elevated serum ALT, LDH and CK-MB levels between dead patients and survival patients (P=0.042, P=0.035 and P=0.017). Logistic regression indicated that the risk factors for death of patients with PTE after orthopaedic surgery were age (OR, 1.182; 95% CI, 1.010-1.383; P=0.036), hypoxemia (OR, 1.128; 95% CI, 1.018-1.249; P=0.022), hypotension (OR, 3.346; 95% CI, 1.116-10.031; P=0.031), right ventricular dysfunction (OR, 4.083; 95% CI, 1.040- 16.035; P=0.044) and elevated serum CK-MB levels (OR, 3.466; 95% CI, 1.054-11.400; P=0.041). CONCLUSION: The incidence rate of elevated serum ALT, LDH and CK-MB levels in patients who died of pulmonary thromboembolism after orthopaedic surgery was higher than that of survival patients; Age, hypoxemia, hypotension and right ventricular dysfunction were independent risk factors of in-hospital death; The CK-MB might be a useful biomarker for risk stratification of acute PTE.