[Influences of leukocytes in patients with type 2 diabetes and periodontitis to the effects of periodontal treatment on glycemic control].

Objective: To analyze the influences of leukocytes on improving blood glucose control in patients with type 2 diabetes mellitus (T2DM) and periodontitis after periodontal mechanical therapy. Methods: Thirty-five patients visiting Peking University Third Hospital from March 2011 to August 2012, as well as thirty-four patients visiting Peking University Hospital of Stomatology from March 2011 to August 2012 and December 2016 to December 2018 were selected in this research. These subjects were non-smokers, and with moderate to severe chronic periodontitis and T2DM. The full set of periodontal examinations including probing depth (PD), attachment loss (AL), bleeding index (BI) and plaque index (PLI) were conducted. Besides, counts of white blood cells (WBC), parameters of glucose and lipids metabolites such as fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL) in serum were examined before treatment. Then, oral hygiene instruction, scaling and root planing (SRP) were carried out. Three months after SRP, the baseline examinations were repeated in all patients. According to the baseline leukocyte counts, the patients were divided into subgroups: low WBC group (WBC<6.19×109/L) and high WBC group (WBC≥6.19×109/L). Paired t-test for comparison of changes after treatment, analysis of co-variance for comparing the intervention effects between subgroups, and multifactor Iogistic regression analysis were performed. Results: Three months after SRP, all periodontal indexes were significantly improved in both groups. Leukocyte counts decreased significantly in high WBC group (7.64±1.51 vs. 6.89±1.53, P=0.008). In high WBC group, HbA1c (7.67±1.35 vs. 7.18±1.09, P=0.001) and LDL (3.28±0.76 vs. 2.67±0.85, P=0.042) decreased significantly, while there were no such differences in low WBC group. Influence of leukocyte level on HbA1c (OR=0.12, P=0.038) and LDL (OR=0.15, P=0.001) improvement was statistically significant. Hierarchical analysis showed such improvement notably perform in female [HbA1c (OR=0.30, P=0.021), LDL (OR=0.34, P=0.001)] and severe periodontitis group [HbA1c (OR=0.15, P=0.025), LDL (OR=0.24, P=0.017)]. Through interaction test, female and leukocyte counts at baseline had relative excess risk affecting the effect of periodontal intervention on HbA1c (P=0.036) and LDL (P=0.005). Conclusions: SRP could significantly improve the blood glucose and lipid control in patients who had T2DM and chronic periodontitis with relative higher leukocytes level. Female patients with severe periodontitis showed more obviously effects.

Importing, caring, breeding, genotyping, and phenotyping a genetic mouse in a Chinese university.

The genetic manipulation of the laboratory mouse has been well developed and generated more and more mouse lines for biomedical research. To advance our science exploration, it is necessary to share genetically modified mouse lines with collaborators between institutions, even in different countries. The transfer process is complicated. Significant paperwork and coordination are required, concerning animal welfare, intellectual property rights, colony health status, and biohazard. Here, we provide a practical example of importing a transgenic mice line, Dynamin 1 knockout mice, from Yale University in the USA to Perking University in China for studying cell secretion. This example including the length of time that required for paper work, mice quarantine at the receiving institution, and expansion of the mouse line for experiments. The procedure described in this paper for delivery live transgenic mice from USA to China may serve a simple reference for transferring mouse lines between other countries too.

Experimental investigation of heat conduction mechanisms in nanofluids. Clue on clustering.

Heat conduction mechanisms in nanofluids, fluids seeded with nanoparticles, have been extensively scrutinized in the past decades to explain some experimental observations of their enhanced thermal conductivity beyond the effective medium theory. Although many mechanisms such as Brownian motion, clustering, ballistic transport, and internanoparticle potential are speculated, experimental proof of any of the mechanisms has been difficult. Here, we investigate the mechanisms experimentally by thermal conductivity measurements and structural analysis for the same materials in both liquid and solid states. These studies strongly suggest that clustering holds the key to the thermal conductivity enhancement of nanofluids.

Influence of organic acids on the transport of heavy metals in soil.

Vegetation historically has been an important part of reclamation of sites contaminated with metals, whether the objective was to stabilize the metals or remove them through phytoremediation. Understanding the impact of organic acids typically found in the rhizosphere would contribute to our knowledge of the impact of plants in contaminated environments. Heavy metal transport in soils in the presence of simple organic acids was assessed in two laboratory studies. In the first study, thin layer chromatography (TLC) was used to investigate Zn, Cd, and Pb movement in a sandy loam soil as affected by soluble organic acids in the rhizosphere. Many of these organic acids enhanced heavy metal movement. For organic acid concentrations of 10mM, citric acid had the highest R(f) values (frontal distance moved by metal divided by frontal distance moved by the solution) for Zn, followed by malic, tartaric, fumaric, and glutaric acids. Citric acid also has the highest R(f) value for Cd movement followed by fumaric acid. Citric acid and tartaric acid enhanced Pb transport to the greatest degree. For most organic acids studied, R(f) values followed the trend Zn>Cd>Pb. Citric acid (10mM) increased R(f) values of Zn and Cd by approximately three times relative to water. In the second study, small soil columns were used to test the impact of simple organic acids on Zn, Cd, and Pb leaching in soils. Citric acid greatly enhanced Zn and Cd movement in soils but had little influence on Pb movement. The Zn and Cd in the effluents from columns treated with 10mM citric acid attained influent metal concentrations by the end of the experiment, but effluent metal concentrations were much less than influent concentrations for citrate <10mM. Exchangeable Zn in the soil columns was about 40% of total Zn, and approximately 80% total Cd was in exchangeable form. Nearly all of the Pb retained by the soil columns was exchangeable.

Thermodynamic modeling of a novel air dehumidification system.

A novel air dehumidification system is proposed. The proposed system incorporates a membrane-based total heat exchanger into a mechanical air dehumidification system, where the fresh air flows through the enthalpy exchanger, the evaporator and the condenser subsequently. Thermodynamic model for the performance estimation of the combined system is investigated. Processes of the fresh air and the refrigerant are studied. Two additional specific programs are devised to calculate the psychrometrics and the thermodynamic properties of the refrigerant R134a. Annual energy requirement is 4.15 × 106 kJ per person, or 33% saving from a system without energy saving measures.

Fast photorefractive response in strongly reduced near-stoichiometric LiNbO(3) crystals.

The photorefractive response time of LiNbO(3) crystal is of the order of minutes, and such a long response time limits the crystal's practical applications. We report the photorefractive properties of nominally pure near-stoichiometric LiNbO(3) crystal that is strongly reduced in vacuum. A short photorefractive response time of the order of 100 ms is measured at a wavelength of 514.5 nm, with incident light intensity of 1.6 W/cm (2) , and possible corresponding mechanisms are discussed. To our knowledge this is the first experimental evidence of a subsecond photorefractive response in pure LiNbO(3) crystals. The diffraction efficiency of a holographic grating written in this reduced crystal is low but can be enhanced by an externally applied electric field.