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- Dextrose prolotherapy for knee osteoarthritis: a randomized controlled trial. [Journal Article]
- Ann Fam Med 2013 May-Jun; 11(3):229-37.
PURPOSE Knee osteoarthritis is a common, debilitating chronic disease. Prolotherapy is an injection therapy for chronic musculoskeletal pain. We conducted a 3-arm, blinded (injector, assessor, injection group participants), randomized controlled trial to assess the efficacy of prolotherapy for knee osteoarthritis.
METHODSNinety adults with at least 3 months of painful knee osteoarthritis were randomized to blinded injection (dextrose prolotherapy or saline) or at-home exercise. Extra- and intra-articular injections were done at 1, 5, and 9 weeks with as-needed additional treatments at weeks 13 and 17. Exercise participants received an exercise manual and in-person instruction. Outcome measures included a composite score on the Western Ontario McMaster University Osteoarthritis Index (WOMAC; 100 points); knee pain scale (KPS; individual knee), post-procedure opioid medication use, and participant satisfaction. Intention-to-treat analysis using analysis of variance was used.
RESULTSNo baseline differences existed between groups. All groups reported improved composite WOMAC scores compared with baseline status (P <.01) at 52 weeks. Adjusted for sex, age, and body mass index, WOMAC scores for patients receiving dextrose prolotherapy improved more (P <.05) at 52 weeks than did scores for patients receiving saline and exercise (score change: 15.3 ± 3.5 vs 7.6 ± 3.4, and 8.2 ± 3.3 points, respectively) and exceeded the WOMAC-based minimal clinically important difference. Individual knee pain scores also improved more in the prolotherapy group (P = .05). Use of prescribed postprocedure opioid medication resulted in rapid diminution of injection-related pain. Satisfaction with prolotherapy was high. There were no adverse events.
CONCLUSIONSProlotherapy resulted in clinically meaningful sustained improvement of pain, function, and stiffness scores for knee osteoarthritis compared with blinded saline injections and at-home exercises.
- Shock-front injector for high-quality laser-plasma acceleration. [Journal Article]
- Phys Rev Lett 2013 May 3; 110(18):185006.
We report the generation of stable and tunable electron bunches with very low absolute energy spread (ΔE≈5 MeV) accelerated in laser wakefields via injection and trapping at a sharp downward density jump produced by a shock front in a supersonic gas flow. The peak of the highly stable and reproducible electron energy spectrum was tuned over more than 1 order of magnitude, containing a charge of 1-100 pC and a charge per energy interval of more than 10 pC/MeV. Laser-plasma electron acceleration with Ti:sapphire lasers using this novel injection mechanism provides high-quality electron bunches tailored for applications.
- Direct Analyte-Probed Nanoextraction Coupled to Nanospray Ionization-Mass Spectrometry of Drug Residues from Latent Fingerprints. [JOURNAL ARTICLE]
- J Forensic Sci 2013 May 17.
Here, we present a method of extracting drug residues from fingerprints via Direct Analyte-Probed Nanoextraction coupled to nanospray ionization-mass spectrometry (DAPNe-NSI-MS). This instrumental technique provides higher selectivity and lower detection limits over current methods, greatly reducing sample preparation, and does not compromise the integrity of latent fingerprints. This coupled to Raman microscopy is an advantageous supplement for location and identification of trace particles. DAPNe uses a nanomanipulator for extraction and differing microscopies for localization of chemicals of interest. A capillary tip with solvent of choice is placed in a nanopositioner. The surface to be analyzed is placed under a microscope, and a particle of interest is located. Using a pressure injector, the solvent is injected onto the surface where it dissolves the analyte, and then extracted back into the capillary tip. The solution is then directly analyzed via NSI-MS. Analyses of caffeine, cocaine, crystal methamphetamine, and ecstasy have been performed successfully.
- Schlieren measurements in the round cylinder of an optically accessible internal combustion engine. [Journal Article]
- Appl Opt 2013 May 10; 52(14):3433-43.
This paper describes the design and experimental application of an optical system to perform schlieren measurements in the curved geometry of the cylinder of an optically accessible internal combustion engine. Key features of the system are a pair of cylindrical positive meniscus lenses, which keep the beam collimated while passing through the unmodified, thick-walled optical cylinder, and a pulsed, high-power light-emitting diode with narrow spectral width. In combination with a high-speed CMOS camera, the system is used to visualize the fuel jet after injection of hydrogen fuel directly into the cylinder from a high-pressure injector. Residual aberrations, which limit the system's sensitivity, are characterized experimentally and are compared to the predictions of ray-tracing software.
- A general liquid chromatography tandem mass spectrometry method for the quantitative determination of diquaternary ammonium gemini surfactant drug delivery agents in mouse keratinocytes' cellular lysate. [Journal Article]
- J Chromatogr A 2013 Jun 14.:98-105.
Development of a simple and rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the quantification of diquaternary ammonium gemini surfactants, utilized as gene deliver agents, is required for the evaluation of their post transfection fate. The continued development of efficient and safe gene delivery agents will benefit directly from an understanding of their rate of uptake, metabolism and excretion. A method is reported that is specific for the quantification of twenty-nine individual diquaternary ammonium gemini surfactant molecules and was validated for N,N-bis(dimethylhexadecyl)-1,3-propane-diammonium dibromide (G16-3) within PAM212 cell lysate according to USFDA bioanalytical method validation guidelines. The 10min chromatographic separation procedure utilized an Agilent Zorbax CN column (100mm×2.1mm with 3μ particles) with LC-MS grade water and acetonitrile, both containing 0.3% (v:v) formic acid and 1mM triethylamine. Extraction of the gemini surfactant from PAM212 keratinocyte cell lysate was performed using octanol and 10μL aliquots were injected onto the column. The standard curve was linear from 0.30μg/mL to 220μg/mL (r(2)≥0.999) for G16-3 and precision and accuracy were within USFDA specified limits. G16-3 analyte was assessed as stable during storage in the auto-injector, bench-top, freeze-thaw cycling and long-term (60 days) storage at -20°C. Evaluation of the cellular uptake and fate of G16-3, during both the incubation and post incubation periods, has established the potential of the application of the LC-MS/MS quantification method for monitoring diquaternary ammonium gemini surfactants in transfection studies.
- Optimization of programmed temperature vaporization injector-preparative capillary gas chromatography for compound specific radiocarbon analysis. [JOURNAL ARTICLE]
- J Sep Sci 2013 Apr 27.
Preparative capillary gas chromatography is a powerful tool for separation and purification of compounds from any complex matrix, which can be used for compound specific radiocarbon analysis. However, the effect of preparative capillary gas chromatography parameters on the trapping efficiency is not well understood. Here we present a comprehensive study on optimization of parameters based on eleven reference compounds with different physicochemical properties. Under the optimum conditions, the trapping efficiencies of eleven compounds (including high boiling point n-hentriacontane and methyl lignocerate) are ca. 80% (60% to 89%). The isolation of target compounds from standard solution, plant and soil samples demonstrates that our optimized method is applicable for different classes of compounds including n-alkanes, fatty acid esters, long chain fatty alcohol esters, PAHs and steranes. By injecting 25 μL in large volume injection mode, over 100 μg, high purity (>90%) target compounds are harvested within 24 h. The recovery ranges of two real samples are ca. 70% (59.9% to 83.8%) and ca. 83% (77.2% to 88.5%). Compared to previous studies, our study makes significant improvement in the recovery of preparative capillary gas chromatography, which is important for its wide application in biogeochemistry, environmental sciences and archaeology. This article is protected by copyright. All rights reserved.
- Electronic temperatures of terahertz quantum cascade active regions with phonon scattering assisted injection and extraction scheme. [Journal Article]
- Opt Express 2013 Apr 22; 21(8):10172-81.
We measured the lattice and subband electronic temperatures of terahertz quantum cascade devices based on the optical phonon-scattering assisted active region scheme. While the electronic temperature of the injector state (j = 4) significantly increases by ΔT = T<sub>e</sub> <sup>4</sup> - T<sub>L</sub> ~40 K, in analogy with the reported values in resonant phonon scheme (ΔT ~70-110 K), both the laser levels (j = 2,3) remain much colder with respect to the latter (by a factor of 3-5) and share the same electronic temperature of the ground level (j = 1). The electronic population ratio n<sub>2</sub>/n<sub>1</sub> shows that the optical phonon scattering efficiently depopulates the lower laser level (j = 2) up to an electronic temperature T<sub>e</sub> ~180 K.
- Generation of high-fidelity few-cycle pulses at 2.1 μm via cross-polarized wave generation. [Journal Article]
- Opt Express 2013 Apr 22; 21(8):9711-21.
We demonstrate the generation of temporally clean few-cycle pulses at 2.1 μm by shortening of 6-optical-cycle pulses via cross-polarized wave (XPW) generation in BaF<sub>2</sub>, CaF<sub>2</sub> and CVD-Diamond crystals. By combining spectra and single-shot third-order intensity cross-correlation traces in a novel Bayesian pulse retrieval technique, we measured pulse durations of 20 fs, corresponding to 2.8 optical cycles. Our results show that XPW generation in the infrared could provide a high-fidelity source of few-cycle pulses for strong-field physics applications. It could also serve as an injector for high-peak power ultrafast mid-IR wavelength parametric amplifiers.
- A piezoelectric drop-on-demand generator for accurate samples in capillary electrophoresis. [Journal Article]
- Talanta 2013 Mar 30.:111-7.
In this work, we propose a piezoelectric droplet generator for injection of well-defined amounts of sample in capillary electrophoresis. We demonstrate stable, precise and drop-on-demand droplet formation for various solutions, with precise control of waveform driving piezoelectric crystal inside the ink-jet head. By tuning the waveform, we can also manipulate the droplet size and delivery frequency. This injector was used in sampling for capillary electrophoresis. As a state-of-the-art application, the analysis of theobromine, caffeine and theophiline using micellar electrokinetic chromatography was developed. The volume of sample (single droplet) analyzed in this experiment was 179pL (RSD=1.2%, n=10). The detection limits for caffeine, theobromine, and theophiline are 0.02, 0.08 and 0.06mML(-1), respectively. Compared with conventional methods, the combination of picoliter droplet dispenser with capillary electrophoresis allows precise and accurate sampling, as well as for reduced sample consumption, which will prove to be an efficient tool in quantitative separation and analysis.
- Preparative Gas Chromatography and Its Applications. [JOURNAL ARTICLE]
- J Chromatogr Sci 2013 Apr 16.
Although hundreds of papers related to preparative gas chromatography (pGC) have been published since the late 1950s, the success of the GC technique has largely been associated with analytical instead of preparative purposes. Actually, pGC is an ideal alternative technique for the preparation of pure substances, especially volatile compounds. This paper reviews the papers (written in English) associated with pGC published over the period from the 1950s to the 2010s. For large scale preparation, large sample injection and vaporization, a high loading capacity column, a gas splitter at the end of the column and a special collecting device are fundamentally important for a pGC system. The primary components of pGC system, including injector, column, splitter, detector and collection traps, are briefly introduced. Furthermore, the applications of pGC in the separation and purification of volatile compounds from natural essential oils, in addition to the purification of isotopes, isomers and enantiomers are summarized.