[Relationship between C-reactive protein level and incidence of left atrial spontaneous echocardiographic contrast in patients with nonvalvular atrial fibrillation].

Objective: To investigate the relationship between high sensitivity C-reactive protein (hs-CRP) level and incidence of left atrial spontaneous echocardiographic contrast (LASEC) in the patients with nonvalvular atrial fibrillation (AF). Methods: Four hundred and ninety consecutive patients with nonvalvular atrial fibrillation who underwent radiofrequency ablation for the first time from January 1, 2018 to June 30, 2018 in the Department of Cardiology, Beijing Anzhen Hospital were enrolled. According to the results of transesophageal echocardiography before radiofrequency ablation, patients were divided into the group without LASEC (n=338) and the group with LASEC (n=152). hs-CRP was determined by latex enhanced immunoturbidimetry. The relationship between hs-CRP and LASEC in patients with nonvalvular atrial fibrillation was investigated by univariate and multivariate logistic analysis. Results: LASEC was detected in 152 (31%) of 490 patients. Significant differences in age, type of atrial fibrillation, previous embolic events, fibrinogen, D-dimer, the left atrial anteroposterior diameter and CHA(2)DS(2)-VASc scores were found between patients with and without LASEC (all P<0.05). Compared with the group without LASEC, the serum hs-CRP level was significantly higher in the group with LASEC (3.16 (1.30, 5.23) mg/L vs. 0.67 (0.37, 1.48) mg/L, P<0.001). Multivariate logistic regression analysis showed that hs-CRP (OR=1.136, 95%CI 1.060 - 1.217, P<0.001) and D-dimer (OR=1.040, 95%CI 1.011 - 1.070, P=0.007) were independent determinants for LASEC in this patient cohort. Conclusions: hs-CRP is an independent determinant for LASEC in patients with nonvalvular atrial fibrillation. Inflammation may thus be involved in the formation of prethrombotic state in patients with nonvalvular atrial fibrillation.

[Association of asymptomatic hyperuricemia with mortality in patients undergoing elective percutaneous coronary intervention].

Objective: This study investigated the influence of asymptomatic hyperuricemia on the prognosis of patients who had undergone elective percutaneous coronary intervention (PCI). Methods: A total of 3 452 consecutive patients , who had preoperative serum uric acid level record and were without gout, underwent elective PCIs between July 2009 and September 2011 were included in this study. Patients were divided into two groups based on their preoperative serum uric acid levels. The association between baseline serum uric acid levels and postoperative mortality was investigated through 1.5 years of follow up. Results: Of the 3 452 patients in the study population, 516 had elevated uric acid and 2 936 had normal uric acid.Patients in the elevated uric acid group were older, more frequently had prior history of hypertension, stroke, myocardial infarction and interventional procedure, less likely to have prior history of diabetes mellitus.Other significant differences included higher white blood cell, total cholesterol and triglyceride levels; lower left ventricular ejection fraction, estimated glomerular filtration rate and high density lipoprotein (HDL) levels, more companied by multivessel disease, more PCI lesions, lower complete revascularization rate.More patients with elevated uric acid level were treated with ACEI/ARB and diuretics at the time of hospital discharge.The results of a multivariate Cox regression analysis revealed that preoperative elevated uric acid was an independent predictive factor for mortality after adjustment for other factors (hazard ratio 3.252, 95% confidence interval 1.902-5.560, P<0.001). Conclusion: Asymptomatic hyperuricemia is an independent predictive factor of mortality in patients undergoing elective PCI.

[The impact of red blood cell distribution width on outcome of elective percutaneous coronary intervention in non-anemia patients].

Objective: Previous studies have revealed that the red blood cell distribution width (RDW) was associated with long-term prognosis in patients undergoing percutaneous coronary intervention (PCI). However, they did not exclude patients with anemia. This study, thus, investigated the association between RDW and prognosis in non-anemia patients. Methods: A total of 2 732 patients underwent elective PCI from July 2009 to September 2011 were enrolled in the study. These patients were divided into two groups based on their baseline median RDW levels: low RDW group (RDW<12.1%) and high RDW group (RDW≥12.1%). All the subjects were followed up for an average period of 18 months and the associations between baseline RDW levels and postoperative mortality were analyzed. Results: Patients in the high RDW group were elder and had more women than those in low RDW group. Most of them had prior history of hypertension, stroke, myocardial infarction, but few of them were current smokers. Subjects in the high RDW group had higher systolic blood pressure and total cholesterol levels, and lower erythrocyte mean corpuscular volume, hemoglobin level, estimated glomerular filtration rate level, and left ventricular ejection fraction. Moreover, more subjects in the high RDW group were combined with left main, ostial and chronic total occlusion lesion, and had a lower complete revascularization rate. The postoperative mortality was significantly higher in the high RDW group than that in the low RDW group (2.4% vs 0.6%, P<0.001). Multivariate Cox regression analysis revealed that preoperative high RDW level was an independent risk factor for postoperative mortality after adjustment of other factors (HR 3.930, 95%CI 1.600-9.656, P=0.003). Conclusion: High RDW might be a marker for the postoperative mortality in non-anemic patients undergoing elective PCI.

Output characteristics of actively Q-switched Ho:LuVO4 laser at room temperature.

A compact continuous wave (CW) and actively Q-switched (AQS) Ho:LuVO4 laser pumped by a 1.94 µm Tm: YAP laser is demonstrated. The performance of the laser was investigated by changing the output coupler. The maximum output power of 4.1 W at 2058.43 nm in CW regime is obtained at the maximum absorbed pump power of 12.3 W. The minimum pulse width of 29.3 ns was obtained at Pulse Repetition Frequency (PRF) of 20 kHz with the same output coupler corresponding to a peak power of 6.9 kW. The maximal output power is 4.1 W with center wavelength of 2058.43 nm at PRF of 40 kHz, corresponding to slope efficiency of 43.0% with respect to absorbed pump power. The M2 factors measured by the traveling knife-edge method are 1.04 in parallel a-axis and 1.08 in parallel c-axis with diffraction limited beam quality.

Doubly Q-switched Ho:LuAG laser with acoustic-optic modulator and Cr²âº:ZnS saturable absorber.

A doubly Q-switched (DQS) Ho:LuAG laser resonantly pumped by a 1.91-µm laser was first presented with an acoustic-optic modulator (AOM) and a Cr2+:ZnS saturable absorber. A comparison among the active Q-switched (AQS), passively Q-switched (PQS), and DQS laser performances was carried out. The maximum continuous wave (CW) output power of 6 W with the central wavelength of 2100.65 nm was obtained at an incident pump power of 35.2 W. Compared with CW laser, the AQS, PQS, and DQS lasers shared the same central wavelength of 2098.34 nm under the same incident pump power. The central wavelength of the AQS and DQS lasers remained constant with the change of AOM repetition frequency (RF). When the incident pump power was 35.2 W and the AOM RF was 15 kHz, the DQS Ho:LuAG laser at a maximum RF of 2.13 kHz achieved the maximum average output power of 4.95 W. At the AOM RF of 10 kHz, the DQS Ho:LuAG laser achieved the shortest pulse width of 40.4 ns with the highest peak power of 61.5 kW. At an incident pump power of 35.2 W, the PQS Ho:LuAG laser obtained the shortest pulse width of 46.1 ns, corresponding to the RF of 2.25 kHz. Experiment results showed that the pulse width could be compressed effectively with a significant increase of peak power for a 2-µm DQS laser.

Efficient Q-switched Ho:GdVO4 laser resonantly pumped at 1942 nm.

An efficient 2 µm room-temperature Q-switched Ho:GdVO4 laser end-pumped by a 1942 nm Tm-fiber laser is demonstrated. To our knowledge, this is the first report of Q-switched performance of Ho:GdVO4 crystal. A maximum CW output power of 6.85 W under the absorbed pump power of 24.1 W was obtained with a slope efficiency of 39.5% at a temperature of 17°C. With the same absorbed pump power, a maximum output energy per pulse of about 0.9 mJ and minimum pulse width of 4.7 ns were obtained at the pulsed repetition frequency (PRF) of 5 kHz, corresponding to a peak power of approximately 187.2 kW.

Single-frequency, Q-switched Ho:YAG laser at room temperature injection-seeded by two F-P etalons-restricted Tm, Ho:YAG laser.

We demonstrated a 1.91 µm pumped, injection-seeded Q-switched Ho:YAG laser operating at room temperature. By inserting two Fabry-Perot etalons into the laser cavity, single-frequency Tm, Ho:YAG seed lasing was achieved at a wavelength of 2090.9 nm, with a typical output power of 60 mW. Single-frequency, nearly transform-limited Q-switched operation of the Ho:YAG laser was achieved by injection seeding. The output energy of the single-frequency Q-switched pulse is 7.6 mJ, with a pulse width of 132 ns and a repetition rate of 100 Hz. We measured the pulse spectrum, half-width of which was 3.5 MHz, by a heterodyne technique.

Lactobacillus kefiranofaciens M1 isolated from milk kefir grains ameliorates experimental colitis in vitro and in vivo.

Lactobacillus kefiranofaciens M1, isolated from and identified in Taiwanese milk kefir grain, has demonstrated immune-modulating activity. In the present study, we further investigated the effects of Lb. kefiranofaciens M1 on intestinal epithelial cells in vitro and on dextran sodium sulfate (DSS)-induced colitis in vivo. The possible mechanisms regarding the cytokine products and intestinal epithelial barrier restoration as well as the putative receptor for the protective effects of Lb. kefiranofaciens M1 were investigated. In vitro results indicated that Lb. kefiranofaciens M1 could strengthen the epithelial barrier function in vitro by increasing the transepithelial electrical resistance (TEER) and significantly upregulated the level of the chemokine CCL-20 at both the apical and basolateral sites. The in vivo effects of Lb. kefiranofaciens M1 on the regulation of intestinal physiology indicate that this strain could ameliorate DSS-induced colitis with a significant attenuation of the bleeding score and colon length shortening. Production of proinflammatory cytokines was decreased and that of the antiinflammatory cytokine IL-10 was increased in the DSS-treated mice given Lb. kefiranofaciens M1. The putative receptor for the protective effects of Lb. kefiranofaciens M1 was toll-like receptor 2 (TLR2), which was involved in probiotic-induced cytokine production in vitro and in attenuation of the bleeding score and colon length shortening in vivo. In this study, the kefir lactobacillus Lb. kefiranofaciens M1 clearly demonstrated an anticolitis effect. Based on these results, Lb. kefiranofaciens M1 has the potential to be applied in fermented dairy products as an alternative therapy for intestinal disorders.

Identification of lactic acid bacteria in Taiwanese ropy fermented milk and evaluation of their microbial ecology in bovine and caprine milk.

The purpose of this study was to identify species of lactic acid bacteria in Taiwanese ropy fermented milk and to study their microbial dynamics during the fermentation process through conventional microbiological cultivation and PCR-denaturing gradient gel electrophoresis. Identification results indicated that Lactococcus lactis ssp. cremoris and Leuconostoc mesenteroides ssp. mesenteroides were the major lactic acid bacteria in Taiwanese ropy fermented milk. Interestingly, 3 groups were identified as Lc. lactis ssp. cremoris using 16S rDNA sequencing, but they showed different denaturing gradient gel electrophoresis patterns and assimilation of carbohydrates. In addition, the microbial dynamics study in different fermentation stages demonstrated that Lc. lactis ssp. cremoris was the most dominant bacterial species in the samples, followed by Leu. mesenteroides ssp. mesenteroides with no differences among the fermentation stages. Finally, the microbial distribution profiles showed that the microbial ecology was different in bovine, caprine, and reconstituted milk, which might further affect the characteristics of the product.

Self-assembly of DNA oligomers into high molecular weight species.

Thermal denaturation, gel electrophoresis, and circular dichroism methods were used to characterize DNA oligomers possessing one or two segments of four contiguous G bases in order to investigate their environmentally dependent conformational properties. The sequences of the oligomers studied were the following: HP1-T series, C4T4G4T5-8; HP1-TG series, C4T4G4T1-4G4. In NaCl at concentrations up to 200 mM, the melting profiles of these oligomers are characterized by single inflection points whose Tm values are independent of DNA concentration. In addition, these oligomers run as single bands in polyacrylamide gels under those same conditions as well as in 100 mM K+ or 20 mM Mg2+. These data suggest that these oligomers exist as intramolecular hairpins comprised of four G:C base pairs in the stems, loops of four T bases, and 3'-overhangs of T5-8 or T1-4G4. In the presence of 100 mM K+ plus 20 mM Mg2+, however, gel electrophoresis indicates that oligomers of the HP1-T series exist as equilibria between parent hairpins and four-stranded structures (i.e., quadraplexes). Quadraplex formation for any member of the HP1-T series requires unfolding of the hairpin, exposing the G4 segment prior to quadraplexation. Members of the HP1-TG series self-assemble into multistranded species of high molecular weight in the presence of 100 mM K+ plus 20 mM Mg2+. For this series of oligomers, the data suggest that these higher order species arise from successive additions of parent oligomer to an initially formed quadraplex.(ABSTRACT TRUNCATED AT 250 WORDS)