In Vitro Effect of 445 nm Blue Laser and 660 nm Low-Level Laser on the Quantity and Quality of Human Gingival Fibroblasts

Low-level laser therapy (LLLT) has several benefits in dentistry, including anti-inflammatory effects and increased proliferation. This study aimed to investigate the effect of 445 nm blue laser and 660 nm low-power laser on the quantity and quality of human gingival fibroblasts in vitro. In this in vitro experimental study, 445 nm and 660 nm lasers were irradiated on the samples six times. After examining the cells on the 7^th and 14^th days, the data were analyzed using ANOVA PASS11 and the post hoc Tukey test. The results showed the positive effect of the 660 nm laser on fibroblast proliferation. The viability on the 7^th day was the highest in the control group, lowest in the 445 nm laser group and highest in the 660 nm laser group on the 14^th day. In the morphological examination, the cells were spherical with narrow appendages in the control group, spindle-shaped with lamellipodia appendages in the 660 nm laser group and spherical with no cytoplasmic appendages in the 445 nm laser group. Evidence of necrosis and granulation phenomenon was observed in the 445 nm laser group. The use of the 660 nm low-power laser, compared with the 445 nm laser, has a positive effect on the quantity and quality of gingival fibroblasts.     

Tris-benzo[cd]indole Cyanine Enables the NIR-photosensitized Radical and Thiol-ene Polymerizations at 940 nm

A near-infrared-absorbing heptamethine ( HM⁺ ) incorporating three bulky benzo[cd]indole heterocycles was designed to efficiently prevent self-aggregation of the dye, which results in a strong enhancement of its photoinitiating reactivity as compared to a parent bis-benzo[cd]indole heptamethine ( HMCl⁺ ) used as a reference system. In this context, we highlight an efficient free-radical NIR-polymerization up to a 100 % acrylates C=C bonds conversion even under air conditions. Such an important initiating performance was obtained by incorporating our NIR-sensitizer into a three-component system leading to its self-regeneration. This original photoredox cycle was thoroughly investigated through the identification of each intermediary species using EPR spectroscopy.     

Comparison on effect of hydrophobicity on the antibacterial and antifungal activities of α-helical antimicrobial peptides

HPRP-A1, a 15-mer α-helical cationic peptide, was derived from N-terminus of ribosomal protein L1 (RpL1) of Helicobacter pylori. In this study, HPRP-A1 was used as a framework to obtain a series of peptide analogs with different hydrophobicity by single amino acid substitutions in the center of nonpolar face of the amphipathic helix in order to systematically study the effect of hydrophobicity on biological activities of -helical antimicrobial peptides. Hydrophobicity and net charge of peptides played key roles in the biological activities of these peptide analogs; HPRP-A1 and peptide analogs with relative higher hydrophobicity exerted broad spectrum antimicrobial activity against Gram-negative bacteria, Gram-positive bacteria and pathogenic fungi, but also showed stronger hemolytic activity; the change of hydrophobicity and net charge of peptides had similar effects with close trend and extent on antibacterial activities and antifungal activities. This indicated that there were certain correlations between the antibacterial mode of action and the antifungal mode of action of these peptides in this study. The peptides exhibited antimicrobial specificity for bacteria and fungi, which provided potentials to develop new antimicrobial drugs for clinical practices.     

Reconstruction of Rabbit Corneal Layer Composed of Corneal Fibroblasts and Corneal Epithelium on the Lyophilized Amniotic Membrane

Introduction Thehumancornea,animportantopticalcompo nentthatfocusesthelightontheiris,isatransparent avasculartissuethatalsoplaysaprotectiveroleforthe eye.Therefore,anyinjury,diseaseorcelldamagethat canleadtoopacificationofthecornea,canimpairthe vision,and…     

Diffusion–Migration Currents on Microelectrodes in the Absence of Supporting Electrolyte at an Arbitrary Charge of Ions

Limiting diffusion–migration currents on microelectrodes in systems comprising two types of electroactive ions and one type of inactive ions with arbitrary charges (z _j) and diffusion coefficients (D _j) are calculated. The electric field which induces the ion migration disappears when the condition D ₁₂/D ₂₁ = z ₁/z ₂ is fulfilled for two types of electroactive ions, where _j are their stoichiometric coefficients in the electrode reaction. For a reversible [Fe(CN)₆]^3–/4– system on microelectrodes, the migration effects are more pronounced as compared with the convective reactant delivery, which is explained by the different nature of the dependence of the limiting current on the diffusion coefficient.     

Effects of Different Doses of Low Power Continuous Wave He–Ne Laser Radiation on Some Seed Thermodynamic and Germination Parameters,and Potential Enzymes Involved in Seed Germination of Sunflower (Helianthus annuus L.)

In this study, water-soaked seeds of sunflower were exposed to He–Ne laser irradiation of different energies to determine whether or not He–Ne laser irradiation caused changes to seed thermodynamic and germination parameters as well as effects on the activities of germination enzymes. The experiment comprised four energy levels: 0 (control), 100, 300 and 500 mJ of laser energy and each treatment replicated four times arranged in a completely randomized design. The experimentation was performed under the greenhouse conditions in the net-house of the Department of Botany, University of Agriculture, Faisalabad. The seed thermodynamic parameters were calculated according to seed germination thermograms determined with a calorimeter at 25.8°C for 72 h. Various thermodynamic parameters of seed (ΔH, (ΔS)_e, (ΔS)_c, (ΔS)_e/Δt and (ΔS)_c/Δt) were affected significantly due to presowing laser treatment. Significant changes in seed germination parameters and enzyme activities were observed in seeds treated with He–Ne laser. The He–Ne laser seed treatment resulted in increased activities of amylase and protease. These results indicate that the low power continuous wave He–Ne laser light seed treatment has considerable biological effects on seed metabolism. This seed treatment technique can be potentially employed to enhance agricultural productivity.     

Comparison of the influence of titanium and chromium adhesion layers on the properties of sol–gel derived NKN thin films

Lead-free (Na_0.5K_0.5)NbO₃ (NKN) thin films were prepared on Pt/X/SiO₂/Si substrates (with the adhesion promoters X = Ti, Cr) by a sol–gel process with and without post-annealing treatment. The effect of the diffusion of the adhesion layer elements Ti and Cr into the NKN film was analysed by secondary ion mass spectrometry, scanning electron microscopy pictures, X-ray diffraction (XRD), and leakage current measurements. It turned out that Cr diffuses into the films to a higher extent than Ti. The high amount of Cr diffusion led to the formation of a secondary phase, as seen in the XRD pattern, and to pore formation on the surface of the NKN films. In contrast, the films with Ti adhesion layer were single phase NKN without pore formation. Also, the leakage current measurements showed a strong influence of the Cr diffusion. The leakage current of the films with Cr adhesion layer was about four orders of magnitude higher than that of the films with Ti adhesion layer. The study shows the strong influence of the adhesion layer of the substrate on the properties of NKN films.     

Influence of the Water Content on the Thermal Behaviour of β-Cyclodextrin at Low and Very Low Temperature

Heat capacities of -CD·9.7H₂O weremeasured by adiabatic calorimetry in the temperature range10–300 K. Differential scanning calorimetry wasused to follow the evolution of the thermalbehaviour versus hydration ratio between 170 and300 K. At least three different behaviours wereobserved, according to the number, n, of watermolecules: 0 < n < 7, 7 < n < 10, and n > 10.These macroscopic results are discussed in terms oforganization differences between the most or theleast hydrated -CD. The structuring effectof the hydration water molecules is emphasised. Theexistence of two energetically distinct -CDhydrates (n < 10 and n > 10) seems to be confirmed. Thishypothesis is discussed in comparison with previousspectroscopic and structural studies.     

Dependence of the volume characteristics and viscosity of solutions of methanol-octane-naphthalene on composition at 25°C

The limiting solubility of naphthalene in a mixture of methanol-octane at 25°C is determined via isothermal saturation. The kinematic viscosity of a mixture of methanol-octane-naphthalene is measured at 25°C. Data on the density of triple mixtures of methanol-octane-naphthalene, used to calculate the partial and apparent molar volumes of naphthalene, are obtained with a high degree of accuracy. The obtained results are discussed in terms of the interactions that occur in solution.     

Pressure and isotope effects on the proton jump of the hydroxide ion at 25°C

The limiting molar conductances Λ⁰ of potassium deuteroxide KOD in D₂O and potassium hydroxide KOH in H₂O were determined at 25°C as a function of pressure to disclose the difference in the proton-jump mechanism between an OH^? (OD^?) and a H₃O⁺ (D₃O⁺) ion. The excess conductance of the OD^? ion in D₂O λ _E ^O (OD ^-), as estimated by the equation $$\lambda _E^O (OD^ - ) = \Lambda ^O (KOD/D_2 O) - \Lambda ^O (KCl/D_2 O)$$ increases a little with pressure as well as the excess conductance of the OH^? ion in H₂O $$\lambda _E^O (OH^ - ) = \Lambda ^O (KOH/H_2 O) - \Lambda ^O (KCl/H_2 O)$$ However, their rates of increase with pressure are much smaller than those of the excess deuteron and proton conductances, λ _E ^O (D ⁺) and λ _E ^O (H ⁺). With respect to the isotope effect on the excess conductance, λ _E ^O (OH ^-)/λ _E ^O (D ⁺) decreases with presure as in the case of λ _E ^O (H ⁺)/λ _E ^O (D ⁺), but the value of λ _E ^O (OH ^-)/λ _E ^O (OD ^-) itself is much larger than that of λ _E ^O (H ⁺)/λ _E ^O (D ⁺) at each pressure. These results are ascribed to the difference in the pre-rotation of water molecules, which is brought about by the difference in the intial orientation of the rotating water molecule adjacent to the OH^? (OD^?) or the H₃O⁺ (D₃O⁺) ion.     

Dynamics of Gas Heating in the Afterglow of Pulsed CO2 and CO2–N2 Glow Discharges at Low Pressure

Plasma Chemistry and Plasma Processing - The time-dependent evolution of the energy transfer into gas heating in the afterglow of pulsed CO2 and CO2–N2 glow discharges produced in cylindrical...     

A Comparison Study on the Interaction of Sunset Yellow and β-Carotene with Bovine Serum Albumin

在模拟生理pH条件（pH=7．4）下,采用多种光谱法研究日落黄和β-胡萝卜素与BSA的相互作用,并比较两者与BSA相互作用过程的差异性．通过荧光光谱法和紫外吸收光谱法确定了日落黄和β-胡萝卜素对牛血清白蛋白的荧光猝灭机制,采用Stern—Volmer、双对数方程和热力学公式求出相互作用的猝灭常数、结合常数配、结合位点数月和作用力类型．结果表明：日落黄和β-胡萝卜素对BSA的猝灭属于静态猝灭,两者与BSA的民都达到10^5L／mol,结合位点数均为1,日落黄与BSA的作用力以静电引力为主,而β-胡萝卜素则是通过氢键和范德华力与BSA作用．通过红外光谱法和圆二色谱法研究了二者对BSA构象的影响,结果表明,日落黄与BSA作用的过程中,会引起BSA二级结构的改变,而β-胡萝卜素则对BSA的构象基本不产生影响．     

Comparison Between the Effects of 2-Selenium Bridged β-Cyclodextrin and Ebselen on Treating SHRsp Stroke

A glutathione peroxidase（GPX） mimic, 2-selenium bridged β-cyclodextrin（2-SeCD）, was synthesized. In order to examine its role and mechanism in treating stroke we chose stroke-prone spontaneously hypertensive rats（SHRsp） as animal model. 56 SHRsps of 8-week olds were randomly divided into several groups： test groups （low, moderate, high dose of 2-SeCD） and control groups（positive and negative）. After onset of the stroke, the rats in test groups were orally administrated with different amounts of 2-SeCD, the positive control group with ebselen, and the negative control group with drinking water. The treatment lasted two weeks, followed by observation of the rats for 10 days, meanwhile blood pressure, biochemical parameters of plasma, and the contents of nitric oxide（NO） and malondialdehyde（MDA） in plasma and brain were determined. The results show that there were significant differences in contents of NO and MDA in plasma and brain between the test groups（high, moderate dose of 2-SeCD） and negative control group. The NO contents of the test groups were obviously higher than that of the negative control group （P〈0.01）. The MDA contents of the test groups（high, moderate dose of 2-SeCD） were obviously lower than that of the negative control group（P〈0.01）. The mechanism of 2-SeCD in treating stroke was discussed, which maybe related to the increase of NO and the decrease of MDA in plasma and brain tissue, but the exact mechanism should be further studied. Moreover, the tendencies of changes in systolic blood pressure, contents of NO and MDA, and other physiological parameters for the test groups were shown to be much better than the corresponding parameters for the positive group（the group with ebselen）（P〈0.05）, indicating that the treatment effect of 2-SeCD is better than that of ebselen.     

Preparation of Langmuir-Blodgett Film of Oligophenylenevinylene at the Air/Water Interface and Study on its Fluorescence

Phenylenevinylene polymers and oligomers were widely investigated as active materialsused in emission layer of light emitting diodes (LEDs), recently, due to their conductingand luminescent properties1-3. Comparing with their polymers, oligophenyl ene-vin…     

Viscosity and thermal conductivity of some refrigerants at moderate and high densities on the basis of Rainwater–Friend theory and the corresponding states principle

The initial density dependence of viscosity and thermal conductivity was formulated on the basis of Rainwater–Friend (RF) theory. In this work, we have first focused on the calculation of viscosity and thermal conductivity of moderately dense argon by using RF theory and an accurate ab initio potential function. This theory which was originally presented for spherical potentials have been adapted for calculation of viscosity and translational contribution of thermal conductivity of some refrigerants by introducing the corresponding states correlations for the second transport virial coefficients. Then the internal states contribution for the thermal conductivity has been determined based on the Mason–Monchick and modified Enskog theories. So, we have calculated the viscosity and thermal conductivity of some refrigerants, R32, R14, R12, R13, R22, R134a, R143a, R125, R123, R142b, at moderate densities up to about 2 mol dm⁻³. At high densities, beyond the validity range of RF theory, we have applied correlation expressions for the viscosity and thermal conductivity residual functions to calculate the viscosity and thermal conductivity of supercritical refrigerants and then compared with the available experimental data. In conclusion, we have shown that the RF theory in conjunction with the corresponding states residual functions present the reliable model for calculation of viscosity and thermal conductivity of refrigerants over a comparatively wide temperature and pressure range up to 65 MPa within the experimental errors.     

Experimental and Theoretical Study of the Effect of Moisture on Methane Adsorption and Desorption by Activated Carbon at 273.5 K

Adsorption and desorption of methane by activated carbon (AC) at constant temperature and at various pressures were investigated. The effect of moisture was also studied. A volumetric method was used, up to 40 bar, at a temperature of 273.5 K. Results of a dry AC sample were compared with those obtained from a moist sample and two different ACs with different physical and surface properties were used. As expected, the results showed that the existence of moisture, trapped in the AC pores, could lead to a decrease in the amount of methane adsorbed and a decrease in the amount of methane delivered during desorption. To model the experimental results, a large variety of adsorption isotherms were used. The regressed parameters for the adsorption isotherms were obtained using the experimental data generated in the present study. The accuracy of the results obtained from the different adsorption isotherms was favorably compared.     

Study on the Phase Equilibrium of the Ternary System Ethanol-Cesium Carbonate-Water at 10, 30 and 50℃

Introduction The salting out effect in the systems of aliphatic al-cohol-water is of industrial interest. The addition of or-ganic solvents to the aqueous solution of a salt normally decreases the solubility of the salt. So the method can be used for salting-out of inorganic salts to improve yield and purity.1-3 However, the phase diagrams of the inves-tigated systems are required as basic data. There are lots of aliphatic alcohol-water systems having been deter-mined. The 1-butanol-water-Na…     

Laser patterning and preferential orientation of two-dimensional planar β-BaB2O4 crystals on the glass surface

The laser-induced crystallization method is applied to pattern two-dimensional planar β-BaB₂O₄ crystals on the surface of Sm₂O₃–BaO–B₂O₃ glass. By scanning Yb:YVO₄ fiber lasers (wavelength: 1080 nm) continuously with a small step (0.5 μm) between laser irradiated areas, homogeneous planar β-BaB₂O₄ crystals are patterned successfully, and a preferential growth orientation of β-BaB₂O₄ crystals is confirmed from linearly polarized micro-Raman scattering spectrum and second harmonic intensity measurements. It is found that the crystal growth direction is perpendicular to the laser scanning direction. This relation, i.e., the perpendicular relation, is different from the behavior in discrete crystal line patterning, where the crystal growth direction is consistent with the laser scanning direction. The present study proposes the possibility of the control of crystal growth direction in laser-induced crystallization in glasses.