Predictive value of complement and coagulation indicators in sepsis related acute kidney injury / 中华内科杂志

Objective:To explore the predictive value of complement and coagulation indicators in sepsis related acute kidney injury (AKI).Methods:Clinical data of 217 patients with sepsis admitted to the Department of Internal Medicine and Intensive Care Unit of Affiliated Hospital of Jiangnan University from January 2018 to June 2019 were retrospectively analyzed. All patients were divided into sepsis with AKI group and without AKI group. Laboratory indicators of all patients were collected, including complement C 3, complement C 4, activated partial thrombin time (APTT), prothrombin time (PT), international normalized ratio (INR), D-dimer, procalcitonin(PCT), etc. logistic regression analysis was used to explore the risk factors of sepsis related AKI. Receiver operating characteristic curve (ROC) was used to evaluate the predictive value of independent risk factors. Results:Among 217 patients, 120 patients developed sepsis related AKI and 97 patients didn′t. PCT, lactic acid, PT, APTT, INR and D-dimer in AKI patients were significantly higher than those without AKI ( P<0.01). Complement C 3 and complement C 4 were significantly lower in AKI group ( P<0.01). Multivariate logistic regression analysis suggested that blood pressure<90/60 mmHg (1 mmHg=0.133 kPa)( OR=3.705, 95% CI 1.536-8.934, P=0.004), increased lactic acid ( OR=1.479, 95% CI 1.089-2.008, P=0.012), decreased complement C 3 ( OR=0.027, 95% CI 0.005-0.152, P<0.001) and prolonged APTT ( OR=1.090, 95% CI 1.047-1.137, P<0.001)were independent risk factors predicting AKI. The area under the ROC curve (AUC) of these multivariates were 0.741 (95% CI 0.675-0.807), 0.798 (95% CI 0.732-0.864), 0.712 (95% CI 0.643-0.781) and 0.716 (95% CI 0.648-0.783) respectively. The relevant sensitivity was 57.5%, 80.8%, 87.5%, 59.2%, and the specificity was 90.7%, 75.3%, 51.5%, 77.3%, respectively. The AUC of the combined four indicators was 0.880 (95 %CI 0.835-0.926) with the sensitivity 75.0% and the specificity 90.7%. Conclusion:The low level of complement C 3 and prolonged APTT predict sepsis related AKI, and the predictive value can be enhanced if hypotension and hyperlactacidemia are added.

Hydrocarbon Degradation and Bacterial Community Responses During Remediation of Sediment Artificially Contaminated with Heavy Oil.

　Natural biodegradation of heavy oil in the marine environment can be accelerated by the addition of nutrients or seeding of pre-selected microorganisms. In this study, a microcosm experiment was conducted to investigate the effects of inorganic nutrient supplementation (biostimulation) and bacterial consortium amendment (bioaugmentation) on the natural degradative processes of artificially contaminated sediment. Our results revealed that the addition of nutrients had greater effect on remediation than the addition of bacterial cells. Supplementation of inorganic nutrients promoted and sustained the growth of oil-degrading and heterotrophic bacteria throughout the experimental period. Highest reduction in the total petroleum hydrocarbons, and of their components, n-alkanes, polycylic aromatic hydrocarbons (PAHs) and alkyl PAHs, were obtained in the biostimulated microcosms. Changes in the bacterial community were monitored by the PCR-DGGE (polymerase chain reaction-denaturing gradient gel electrophoresis) method targeting the 16S rDNA gene. Results revealed different responses of the bacterial community to the addition of heavy oil and remediation agents. Shifts in the bacterial communities in the seawater were more dynamic than in the sediment. Results of this study showed that addition of remediation agents significantly enhanced the natural biodegradation of heavy oil in a sediment-seawater microcosm trial.

Isolation and characterization of bacterial isolates algicidal against a harmful bloom-forming cyanobacterium Microcystis aeruginosa.

Algicidal bacteria MaI11-2, MaI11-5 and MaI11-10, which inhibited the growth of a harmful bloom-forming cyanobacterium Microcystis aeruginosa, were isolated from a sewage treatment plant. The isolate MaI11-5 was phylogenetically affiliated into the genus Pedobacter, while MaI11-2 and MaI11-10 were closely related to Bacillus aerophilus, Bacillus altitudinis and Bacillus stratosphericus with 100% identity based on 16S ribosomal RNA sequences. Co-cultivation of M. aeruginosa with the algicidal isolates showed their high algicidal activity. MaI11-5 showed the highest inhibitory effect on the cyanobacterial growth: the inhibitory effect exceeded 50% after 2 days, and reached to 75-85% after 10 days, regardless of the bacterial cell density. The cyanobacterial cells aggregated and produced mucilaginous, glycocalyx-like compounds when attacked by the algicidal bacteria. These results suggest that the algicidal bacteria isolated in the present study are potentially useful as biocontrol agents against M. aeruginosa bloom.