Ru-Based Organometallic Agents Bearing Phenyl Hydroxide: Synthesis and Antibacterial Mechanism Study against Staphylococcus aureus.

The development of antimicrobial agents with novel model of actions is a promising strategy to combat multiple resistant bacteria. Here, three ruthenium-based complexes, which acted as potential antimicrobial agents, were synthesized and characterized. Importantly, three complexes all showed strong bactericidal potency against Staphylococcus aureus. In particular, the most active one has a MIC of 6.25 µg/mL. Mechanistic studies indicated that ruthenium complex killed S. aureus by releasing ROS and damaging the integrity of bacterial cell membrane. In addition, the most active complex not only could inhibit the biofilm formation and hemolytic toxin secretion of S. aureus, but also serve as a potential antimicrobial adjuvant as well, which showed synergistic effects with eight traditional antibiotics. Finally, both G. mellonella larva infection model and mouse skin infection model all demonstrated that ruthenium complex also showed significant efficacy against S. aureus in vivo. In summary, our study suggested that ruthenium-based complexes bearing a phenyl hydroxide are promising antimicrobial agents for combating S. aureus.

[Gender differences of genetic etiology in the incidence of major depressive disorder among Han freshmen].

Objective: To analyze the gender differences of genetic etiology in the incidence of major depression disorder among Han freshmen. Methods: A 1-year follow-up survey was carried out among 8 079 Han freshmen from Jining, Rizhao and Weifang without lifetime major depressive disorder (MDD) at baseline (April to October 2018) and 4 828 venous blood samples were also collected. After extracting DNA, Sequenom Mass Array time-of-flight mass spectrometry biochip technology was used to detect the genotypes of 17 single nucleotide polymorphisms (SNPs) MDD-related loci. Logistic regression was used for univariate analysis. Generalized multifactor dimension reduction was used to analyze gene-gene interactions. Composite International Diagnostic Interview (CIDI) 3.0 was used for MDD diagnosis. Results: The 1-year incidence of MDD among Han freshmen was 2.23% (95%CI: 1.91%-2.60%) and the gender difference of incidence between males (1.97%, 95%CI: 1.52%-2.56%) and females (2.39%, 95%CI: 1.98%-2.90%) was not statistically significant (P>0.05). AG genotype of rs768705 (nearby gene: TMEM161B) was a risk factor for MDD (OR=1.98, 95%CI: 1.24-2.83). The TC genotype of rs17727765 (nearby gene: CRYBA1) was only a risk factor for MDD in males (OR=9.61, 95%CI: 2.04-45.30). An 8-loci interaction model (PMFBP1, OLFM4, LHPP, ENOX1, TMEM161B, SPPL3, FBXL4 and L3MBTL2) could predict MDD in women with an accuracy rate of 60.05%. No effective prediction model was found for MDD in men. Conclusions: There might be gender differences in the genetic etiology of MDD. Further researches on the genetic causes of MDD in men should be explored.

[Combined detection of KRAS, NRAS, BRAF and PIK3CA mutations in the plasma and tumor tissues of colorectal cancer patients].

Objective: To analyze the concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations detected in plasma and matched tumor tissues in colorectal cancer patients, in order to provide good evidences to support plasma could be a potential surrogate of tumor tissue for gene mutation test. Methods: One hundred and seventy-five cases of colorectal cancer were collected at the First Hospital of Jilin University, from October 2016 to October 2017.There were 101 males and 74 females, their ages ranged from 28 to 85 years,with median age of 59 years. The KRAS, NRAS, BRAF and PIK3CA gene mutations in the plasma and paired tumor specimens of all patients were detected by next generation sequencing. Results: The results of tissue samples test were gold standard. Comparison of the four genes showed that concordance rates between plasma and tissue samples were 81.1%(Kappa=0.543), 99.4%(Kappa=0.886), 99.4% (Kappa=0.886) and 97.7%(Kappa=0.714) respectively for KRAS, NRAS, BRAF and PIK3CA. The plasma detection rates of these genes were related to tumor stage(P=0.001), but not to gender(P=0.468) and age(P=1.000) of patients. Conclusions: The study shows a high concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations in plasma against mutation status in tumor tissue. In colorectal cancer, tumor tissue remains the best specimen for gene detection. However, patients from tumor tissue specimens cannot be obtained, especially those with advanced metastases, plasma can be used instead of tissue to detect the mutation status of KRAS, NRAS, BRAF and PIK3CA to guide targeted therapy.

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.

Relationship between serum levels of endogenous secretory RAGE and blood pressure in male nondiabetic patients with obstructive sleep apnea.

The interaction of advanced glycation end products (AGE) and their specific cell-surface receptor (RAGE) has an important role in the pathogenesis of cardiovascular disease and diabetic complications. Two isoforms of C-truncated RAGE, soluble RAGE (sRAGE) and endogenous secretory RAGE (esRAGE), may prevent activation of RAGE signaling by acting as decoys. This study investigated whether serum esRAGE and sRAGE levels are associated with blood pressure in nondiabetic patients with obstructive sleep apnea (OSA). Male nondiabetic patients (n=139) with OSA were enrolled. Serum esRAGE and sRAGE levels were examined using enzyme-linked immunosorbent assay. Three consecutive seated systolic blood pressure (SBP) and diastolic blood pressure (DBP) measurements were obtained at 5-min intervals in the morning. In univariate analysis, there was a significant correlation between serum esRAGE and SBP or DBP, but not between serum sRAGE and SBP or DBP. Multiple regression analysis showed that SBP was independently associated with waist circumference, HbA1c, minimum SaO2 and serum esRAGE, and that DBP was independently associated with low-density lipoprotein cholesterol, apnea-hypopnea index, serum AGE and body mass index, but not with serum esRAGE. These results indicated that serum esRAGE levels were inversely associated with blood pressure, especially SBP, in male nondiabetic patients with OSA. esRAGE may have a protective role against hypertension in patients with OSA, and it may be a novel biomarker for OSA patients at high risk of developing cardiovascular diseases.

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.

Resonantly pumped room temperature Ho:LuVO4 laser.

Spectroscopic characterization of a Ho:LuVO4 crystal grown by the Czochralski method has been performed, including the absorption and emission spectra. We demonstrate a 2 µm room temperature Ho:LuVO4 laser, resonantly pumped by a 1.94 µm Tm:YAP laser. By use of an output coupler with T=10% transmission, the Ho:LuVO4 laser generated continuous-wave output power of 2.5 W at 2074.18 nm, with a beam quality factor of Mx2=My2=1.3, for a total incident pump power of 19.4 W. The slope efficiency with respect to the pump power was 17.6%, and the optical-to-optical efficiency was 12.9%. Moreover, we obtained a Ho:LuVO4 laser that operated at 2073.77 and 2055.27 nm, by using different output couplers with transmissions of T=15 and 30%.

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.

Room temperature single longitudinal mode laser output at 1645 nm from a laser-diode pumped Er:YAG nonplanar ring oscillator.

We report on a monolithic 1645 nm Er:YAG nonplanar ring oscillator (NPRO) resonantly pumped by a fiber-coupled laser diode. In the experiment, an up to 550 mW single frequency laser output at 1645.2 nm was obtained, corresponding to a slope efficiency of 19.1% and an absolute efficiency of 6.0%. The beam quality M2 was measured to be 2.1 at the highest output power.

Strain effect on the diffusion of interstitial Mn in GaAs.

The influence of external strain on the diffusion barriers of interstitial Mn in GaAs is studied using the first-principles calculations within the density functional theory. The diffusion barrier changes with strain in different manners: linear on the tensile strain and nonlinear on compressive strain, in contrast to the linear behavior of the continuum elastic model. The discrepancy between the continuum elastic model and the results of the first-principles method is attributed to the energy-level crossing caused by strain. Moreover, we find that the external strain can not only effectively change the diffusion barrier (even to zero, at certain strain), but also the position of saddle points along the migration path. Our finding provides an alternative way to reduce the population of interstitial Mn in GaAs, thus correspondingly to increase the Curie temperature of this system.

Association of lipopolysaccharide-binding protein gene polymorphisms with cerebral infarction in a Chinese population.

Toll-like receptors (TLRs) have been widely known for their role as an important mediator of immune reactions in the development and progression of atherosclerotic (AS) lesions, which play the most important role in the occurrence of cerebral infarction (CI). The lipopolysaccharide (LPS)-lipopolysaccharide binding protein (LBP) compounds connect LPS receptor-CD14 and play an important role in promoting inflammatory reaction through TLRs. This study was designed to study whether LBP genetic polymorphisms are associated with CI risk in a Chinese population. LBP c.291T>C and c.1306T>C single nucleotide polymorphisms (SNPs) were genotyped in 366 CI cases and 200 controls from Changsha by using method of Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Blood lipid and lipoprotein levels were also detected and the intima-media thickness (IMT) of carotid arteries were determined. No significant difference in genotype and allele distribution of the LBP c.291T>C and LBP c.1306T>C polymorphism was observed between the cases and controls (P > 0.05). CI patients carrying the TC genotype for both LBP c.291T>C and c.1306T>C polymorphisms showed higher carotid IMT than those carrying the TT genotype (P < 0.05, respectively). LBP c.291T>C and c.1306T>C polymorphisms were significantly associated with carotid IMT in Changsha, China, but both polymorphisms were not associated with risk of atherosclerotic CI.

Room temperature single-frequency output from a diode-pumped Tm,Ho:YAP laser.

Single-frequency operation in the range of 2102.45-2102.54 nm and 2130.72-2130.82 nm is demonstrated from a Tm,Ho:YAP laser at room temperature. To our knowledge, this is the first time a room temperature single-frequency Tm,Ho:YAP laser of up to 72.6 mW at 2102.5 nm with Fabry-Perot etalons has been obtained. Regulating the elevation angle of the two etalons, 42.0 mW at 2130.8 nm was obtained. The single-longitudinal-mode laser can be used as a seed laser for coherent wind measurements and differential absorption lidar systems.

[Abnormal expression of the FHIT gene in human primary gastrointestinal cancers].

OBJECTIVE: To evaluate the relationship between FHIT gene and gastrointestinal cancers. METHODS: Matched normal and cancerous tissues from 26 patients with primary gastric carcinoma and 30 patients with colorectal carcinoma were analysed by nested polymerase chain reaction(RT-PCR) and direct sequencing of the products. RESULTS: Seven of 26(26.9%) gastric cancer tissues and eight of 30(26.7%) colorectal cancer tissues expressed aberrant FHIT transcripts, but no aberrant FHIT transcript was observed in all the matched normal tissues. Sequence analysis of the aberrant transcripts of 2 gastric cancer tissues(G8T, G25T) and 2 colorectal cancer tissues(C5T, C26T) confirmed the absence of 1 to 3 exons of FHIT gene. CONCLUSIONS: The expression of aberrant FHIT transcripts is common and tumor-specific in gastrointestinal cancers and abnormalities of FHIT gene may be associated with gastrointestinal tumorigenesis.

[Anti-tumor effects of ailing-1 on human megakaryoblastic leukemia cells].

OBJECTIVE: To evaluate the anti-cancer effect of Ailing-1 on human megakaryoblastic leukemia cells in culture. METHODS: Using living cell counting, 3H-TdR incorporation and clonal proliferation assay. RESULTS: Ailing-1 has various cytotoxicity on cell level, DNA synthesis and clone proliferation and shows good does-effect relation. The ED50 of Ailing-1 is greater than that of homoharringtonine through three different methods, consistent with the clinical result. Drug resistance has not been found. CONCLUSION: Ailing-1 is a promising anti-tumor drug.