[Association between onset time of sepsis-associated acute kidney injury and clinical outcome in patients with sepsis].

Objective: To explore the relationship between the onset time of sepsis-associated acute kidney injury (SA-AKI) and adverse clinical outcomes. Methods: Data were derived from Beijing Acute Kidney Injure Trial (BAKIT) which investigated the epidemiology of acute kidney injury (AKI) in critically ill patients at 30 intensive care units (ICU) of 28 tertiary hospitals in Beijing from 1 March to 31 August 2012. Patients who were older than 18 years and diagnosed with sepsis and AKI, and expected to stay in ICU for at least 24 h were included in this study. A total of 653 patients were included in this study, 414 males and 239 females with a mean age of (68.2±17.0) years. According to the onset time of SA-AKI, patients were grouped into early AKI (E-AKI) (AKI occurred within 48 hours after ICU admission) and late AKI (L-AKI) (AKI occurred after 48 hours of ICU admission) group. The primary outcome was major adverse kidney events (MAKE), consisted of all-cause mortality, renal replacement therapy-dependence, and an inability to recover to 1.5 times of the baseline creatinine value up to 30 days. Multivariable logistic regression was used to investigate the association between the onset time of SA-AKI and clinical outcomes. Results: A total of 653 patients with SA-AKI were included, 423 (64.8%) patients developed E-AKI, 230 (35.2%) cases developed L-AKI, MAKE occurred in 405 (62.0%) cases, and 301 (46.1%) patients died in hospital. Compared with E-AKI group, L-AKI patients showed higher AKI 3 level rate [55.7%(128/230) vs 40.2%(170/423), P<0.001], incidence of MAKE [72.6%(167/230) vs 56.3%(238/423,P<0.001)] and hospital mortality [55.2%(127/230) vs 44.1%(174/423), P=0.001]. The risk of MAKE and in-hospital mortality in L-AKI group increased for 2.55-fold times (OR=3.55, 95%CI: 1.94-6.04) and 1.84-fold times (OR=2.84, 95%CI: 1.44-5.60) when compared with those in E-AKI, respectively (both P<0.05). Conclusion: Late timing onset of SA-AKI is associated with poor clinical outcomes.

[Dose-response association between fluid overload and hospital mortality in patients with sepsis].

Objective: To investigate dose-response associations between fluid overload (FO) and hospital mortality in patients with sepsis. Methods: The current cohort study was prospective and multicenter. Data were derived from the China Critical Care Sepsis Trial, which was conducted from January 2013 to August 2014. Patients aged≥18 years who were admitted to intensive care units (ICUs) for at least 3 days were included. Fluid input/output, fluid balance, fluid overload (FO), and maximum FO (MFO) were calculated during the first 3 days of ICU admission. The patients were divided into three groups based on MFO values: MFO<5%L/kg, MFO 5%-10%L/kg, and MFO≥10% L/kg. Kaplan-Meier analysis was used to predict time to death in hospital in the three groups. Associations between MFO and in-hospital mortality were evaluated via multivariable Cox regression models with restricted cubic splines. Results: A total of 2 070 patients were included in the study, of which 1 339 were male and 731 were female, and the mean age was (62.6±17.9) years. Of 696 (33.6%) who died in hospital, 968 (46.8%) were in the MFO<5%L/kg group, 530 (25.6%) were in the MFO 5%-10%L/kg group, and 572 (27.6%) were in the MFO≥10%L/kg group. Deceased patients had significantly higher fluid input than surviving patients during the first 3 days [7 642.0 (2 874.3, 13 639.5) ml vs. 5 738.0 (1 489.0, 7 153.5)ml], and lower fluid output [4 086.0 (1 367.0, 6 354.5) ml vs. 6 130.0 (2 046.0, 11 762.0) ml]. The cumulative survival rates in the three groups gradually decreased with length of ICU stay, and they were 74.9% (725/968) in the MFO<5% L/kg group, 67.7% (359/530) in the MFO 5%-10%L/kg group, and 51.6% (295/572) in the MFO≥10%L/kg group. Compared with the MFO<5%L/kg group, the MFO≥10%L/kg group had a 49% increased risk of inhospital mortality (HR=1.49, 95%CI 1.28-1.73). For each 1% L/kg increase in MFO, the risk of in-hospital mortality increased by 7% (HR=1.07, 95% CI 1.05-1.09). There was a"J-shaped"non-linear association between MFO and in-hospital mortality with a nadir of 4.1% L/kg. Conclusion: Higher and lower optimum fluid balance levels were associated with an increased risk of in-hospital mortality, as reflected by the observed J-shaped non-linear association between fluid overload and inhospital mortality.

[Association between fluid balance and clinical outcomes in sepsis patients with identified subtypes].

Objective: To identify clinical subphenotypes of sepsis by clinical variables, and the association between fluid balance (FB) and outcomes in sepsis patients with different subphenotypes. Methods: Data were derived from China Critical Care Sepsis Trial. A total of 2 075 patients were included in the study, with a mean age of (62.5±17.4) years, 1 362 (65.6%) were male, 713 (34.3%) were female. In-hospital mortality was the primary outcome. Clinical variables were entered into the latent profile analysis (LPA) model which was used to identify the subphenotypes of sepsis. Multivariable logistic regression model was used to explore the association of FB on the first 2 days admitted to ICU and in-hospital mortality. Results: Total of 687 (33.1%) patients died in the hospital. Four subphenotypes of sepsis were identified by the PLA model: 1 421 (68.5%) patients were identified as profile 1, which was characterized by the lowest in-hospital mortality (28.3%, 402/1 421) and was considered as the baseline subphenotype; profile 2 was characterized by multiple organ dysfunction(232, 11.2%); profile 3 was characterized by respiratory dysfunction (196, 9.4%) and profile 4 was characterized by kidney injury/failure (226, 10.9%). Profile 2 showed the highest in-hospital mortality (54.3%, 126/232), followed by profile 4 (39.4%, 89/226), profile 3 (35.7%, 70/196). Profile 2 had the highest FB of 68.5(34.7, 89.4)ml/kg on day 1 and decreased rapidly to 29.4(13.6, 49.8) ml/kg on day 2. Multivariable analysis showed that for every 10 ml/kg of FB increased on the first 48 hours admitted to ICU, the risk of in-hospital mortality decreased 14% (OR=0.86, 95%CI: 0.81-0.97) in profile 2, and increased 4% (OR=1.04, 95%CI:1.02-1.07) in profile 4. However, there were no significant association between FB on the fist 2 days admitted to ICU and the risk of in-hospital mortality in profile 1 (OR=1.06, 95%CI: 0.94-1.19)and in profile 3 (OR=0.99, 95%CI: 0.94-1.05). Conclusions: Four subphenotypes of sepsis were identified according to the clinical variables, which showed different characteristics, distributions, outcomes and responses to fluid balance.

[The epidemiology of bloodstream infections in Fuxing Hospital in 2012 in Beijing].

OBJECTIVE: To investigate the etiology, clinical features and outcome of hospitalized patients with bloodstream infections (BSIs) in a tertiary hospital. METHODS: Positive blood cultures were obtained from the microbiological laboratory in Fuxing Hospital, Capital Medical University from January 1, 2012 to December 31, 2012. BSIS events were identified and the epidemiology data were collected. RESULTS: A total of 149 patients and 154 BSIs events were confirmed by pathogenic and clinical evidence. The in-patients' BSIs rate was 0.8% in our hospital in 2012. According to the disease entities of the first BSIs onset, 15 patients (10.1%) were from surgical departments, 83 patients (55.7%) from the medical departments, and 51 patients (34.2%) from ICU. Thirty-three patients (22.1%) were diagnosed as septic shock. Sixty-eight patients died during hospital stay. The in-hospital mortality rate was 45.6%. Among the 154 BSIs events, 125 (81.2%) were nosocomial and 29 (18.8%) were community-acquired. A total of 188 strains were isolated from all BSIs, including 106 strains of (56.4%) gram-negative bacilli, 67 (35.6%) strains of gram-positive bacteria, and 15 (8.0%) strains of fungi. One hundred and fifty-nine strains of bacteria (84.6%)were isolated from 125 events of hospital-acquired BSIs. Twenty-six strains of bacteria were from catheter related bloodstream infections (CRBSIs). In gram-negative BSIs, there were more enterobacteriaceae in community-acquired BSIs. More non-fermentative bacteria were found in hospital-acquired BSIs than in community-acquired ones. The distribution of gram-negative bacilli was quite different between surgical departments, non-surgical departments and ICU (P=0.049). CONCLUSIONS: Pathogens of BSIs are quite different according to disease entities and where the patients are from. Local epidemiology of BSIs and distribution of related pathogens are helpful to physicians searching the optimal empirical antibiotics and improving the outcome.

Current sensing using circularly birefringent twisted solid-core photonic crystal fiber.

Continuously twisted solid-core photonic crystal fiber (PCF) exhibits pure circular birefringence (optical activity), making it ideal for current sensors based on the Faraday effect. By numerical analysis, we identify the PCF geometry for which the circular birefringence (which scales linearly with twist rate) is a maximum. For silica-air PCF, this occurs at a shape parameter (diameter-to-spacing ratio of the hollow channels) of 0.37 and a scale parameter (spacing-to-wavelength) of 1.51. This result is confirmed experimentally by testing a range of different structures. To demonstrate the effectiveness of twisted PCF as a current sensor, a length of fiber is placed on the axis of a 7.6 cm long solenoid, and the Faraday rotation is measured at different values of dc current. The system is then used to chart the wavelength dependence of the Verdet constant.

Enhanced optical activity and circular dichroism in twisted photonic crystal fiber.

We demonstrate experimentally and theoretically that the core-guided mode in helically twisted photonic crystal fiber exhibits resonantly enhanced optical activity and circular dichroism in the vicinity of anti-crossings with leaky orbital angular momentum (OAM) modes in the cladding. This arises because the anti-crossings for left and right circularly polarized core modes occur at slightly different wavelengths.

Individualized treatment of NSCLC: from research to clinical practice.

The exact clinical significance of EGFR mutation status in NSCLC at the time of initial diagnosis remains disputable. The gene expression module in NSCLC for chemotherapy outcome prediction needs to be developed. We analyzed 56 patients with NSCLC received chemotherapy either with (n=20) or without EGFR-TKIs (n=36) between 2008 and 2012 in China. EGFR mutation test and gene expression profiling were performed in samples obtained before medication treatment by liquidchip platform. Significant association (P = 0.028) was seen between EGFR mutation status before first-line chemotherapy and EGFR-TKIs treatment outcomes, which even can be found from the status before second- or third-line treatment. A14-gene expression profiling had been studied. Patients with low mRNA expression of ERCC1 or TYMS preferred higher DCR to cisplatin and pemetrexed than those with high expression (P = 0.39 and P= 0.11). Highly co-expression of TUBB3 and STMN1 gene has associated with the resistance to antimicrotubule drugs (P = 0.03). Our data suggest the EGFR mutations status, even at the time of initial diagnosis, is predictive of outcomes of TKIs treatment after chemotherapy. The mRNA expression profiling investigated in this study has a predictive value in NSCLC treatment, but further research with expanded samples is still required.

Optical activity in twisted solid-core photonic crystal fibers.

In this Letter we show that, in spectral regions where there are no orbital cladding resonances to cause transmission loss, the core mode of a continuously twisted photonic crystal fiber (PCF) exhibits optical activity, and that the magnitude of the associated circular birefringence increases linearly with twist rate and is highly reproducible. In contrast to previous work on twist-induced circular birefringence, PCF has zero linear birefringence and an on-axis core, making the appearance of circular birefringence rather unexpected. A theoretical model based on symmetry properties and perturbation theory is developed and used to show that both spin and orbital angular momentum play a role in this effect. It turns out that the degenerate left- and right-circularly polarized modes of the untwisted PCF are not 100% circularly polarized but carry a small amount of orbital angular momentum caused by the interaction between the core mode and the hollow channels.