Post-tonsillectomy hemorrhage in children: a single surgeon’s experience with coblation compared to diathermy

The aim of this study was to compare coblation and diathermy techniques with respect to secondary post-tonsillectomy hemorrhage (PTH). A total of 1,397 children underwent tonsillectomies with or without adenoidectomy by a single surgeon in a single center from June 2005 through December 2011. A diathermy tonsillectomy was performed on 315 patients for the first 2 years, while a coblation tonsillectomy was performed on 1,082 for the next 5 years. All patients were followed-up within 28 days of surgery by the same surgeon. The characteristics of primary and secondary PTH were analyzed with a retrospective chart review. Primary PTH did not occur in both surgical technique groups. Secondary PTH occurred in 9 patients (2.9 %) in the diathermy group and in 30 patients (2.8 %) in the coblation group. The secondary PTH rates were 1.2, 2.5, 3.8, 3.1 and 4.5 % in the first, second, third, fourth and fifth years after employment of the coblation tonsillectomy, respectively (P = 0.243). Sex, age, tonsil size and severity of tonsillar embedding were not significant factors for PTH. The coblation technique was associated more with late secondary PTH than diathermy technique (odds ratio 9.14, P = 0.049). Analysis of the time of onset of PTH showed that secondary PTH occurred most commonly between 6 p.m. and 6 a.m. In summary, coblation technique has similar secondary PTH rate with diathermy technique although it has increased late secondary PTH rate in children. Coblation technique can be a good alternative to the diathermy technique.     

High sensitivity nanoparticle detection using optical microcavities

We demonstrate a highly sensitive nanoparticle and virus detection method by using a thermal-stabilized reference interferometer in conjunction with an ultrahigh-Q microcavity. Sensitivity is sufficient to resolve shifts caused by binding of individual nanobeads in solution down to a record radius of 12.5 nm, a size approaching that of single protein molecules. A histogram of wavelength shift versus nanoparticle radius shows that particle size can be inferred from shift maxima. Additionally, the signal-to-noise ratio for detection of Influenza A virus is enhanced to 381 from the previously reported 31. The method does not use feedback stabilization of the probe laser. It is also observed that the conjunction of particle-induced backscatter and optical-path-induced shifts can be used to enhance detection signal-to-noise.     

Polymorphic and kinetic investigation of adefovir dipivoxil during phase transformation

To search polymorphs of adefovir dipivoxil (AD), the polymorphic transformation approach in solution was developed. Also, the kinetics of polymorphic transformation was investigated to effectively control polymorphs. The AD crystals were obtained by crystallization at -10°C, and then the polymorphic transformation was induced by raising temperature. The polymorphs of AD were confirmed using DSC, XRD and solubility analyses. The polymorphic fraction during transformation was monitored for kinetic investigation. Via polymorphic transformation in solution, four polymorphs of AD were found and two of them were new (NF-I, NF-II). The DSC analysis revealed that solvate form (NF-I) was changed to form-V in solid state, and then re-crystallized to NF-II at 93°C, and finally became form-I at 97°C. This serial change of polymorphs in DSC was identical to polymorphic transformation sequence in solution. The kinetic rates of polymorphic transformation described by nucleation and mass transfer theories were well matched with experimental measurement. The polymorphic transformation approach was effective to search polymorphs of which the structure was changed to the other one in the solution. The kinetic information of polymorphic transformation predicted by Volmer's nucleation model and Stokes-Einstein diffusion equation was valuable for exact control of polymorphic purity.     

Viability and Regeneration of Chondrocytes after Laser Cartilage Reshaping Using 1,460 nm Diode Laser

Objectives

Cartilage reshaping by laser irradiation is used to correct septal and auricular cartilage deformities. Chondrocyte viability following laser irradiation and reshaping has been well established. However, the regeneration process of chondrocyte after laser irradiation has not been revealed yet. The aims of this study were to determine the mechanism of cartilaginous thermal injury and the regenerative process of damaged cartilage following laser irradiation.

Methods

Laser irradiation was performed on human septal cartilage and rabbit auricular cartilage using a 1,460-nm diode laser. We observed change in the shape of cartilage and evaluated the extent of cartilage injury using live/dead cell assay via confocal microscopy. Hoechst and propidium iodide (PI) staining was used to evaluate the mechanism of chondrocyte injury after laser irradiation. To evaluate the regeneration of cartilage, laser irradiated cartilages were reimplanted into a subperichondrial pocket and were harvested at 1, 2, and 4 weeks after reimplantation for viability assessment and histologic examination.

Results

Laser irradiation using a 1,460-nm diode laser produced a marked shape change in both human septal and rabbit auricular cartilages. Thermal damage on cartilage was correlated with the exposure time and the laser power. Hoechst and PI staining showed that chondrocyte death by laser irradiation was due to mainly necrosis, rather than apoptosis. In lower power treatment group (0.3 W and 0.5 W), all the chondrocytes regenerated within 4 weeks, however, in 1 W treatment group, chondrocytes could not regenerate until 4 weeks.

Conclusion

Reshaping of cartilage using 1,460 nm diode laser was attained concurrently with the thermal injury to the chondrocytes. The extent of thermal damage on chondrocytes was dependent on the exposure time and the laser power and the damaged chondrocytes irradiated with lower level of laser power could be regenerated after reimplantation into subperichondrial pocket.     

Simultaneous determination of fourteen components of Gumiganghwal-tang tablet in human plasma by UPLC-ESI-MS/MS and its application to pharmacokinetic study

Gumiganghwal-tang is a traditional herbal medicine widely used for its anti-inflammatory, analgesic, and antipyretic effects. However, the safety and efficacy of its active ingredients based on an in vivo pharmacokinetic (PK) study have yet been investigated. We have established a sensitive and accurate UPLC-ESI-MS/MS method and conducted a PK study on 14 constituents of Gumiganghwal-tang through human plasma analysis. Analytical conditions were optimized according to the physicochemical properties of the 14 compounds to facilitate efficient separation and eliminate overlap or interference between peaks. KINETEX-C₁₈ and Inertsil-C₈ columns were used as UPLC stationary phases, and acetonitrile and aqueous formic acid were used as mobile phases. All the analytes were quantified with a triple quadrupole mass spectrometer using electrospray ionization in multiple reaction monitoring mode. The chromatograms of 14 bioactive compounds showed excellent elution and sensitivity, and each peak was selectively separated and quantified without interference with each other or impurities. The established analytical method was based on international guidelines and was successfully used to perform PK studies of 14 herbal ingredients in humans after oral administration with Gumiganghwal-tang tablets. The oral absorption of most active components of Gumiganghwal-tang was relatively rapid and remained considerably long in the body to be quantified in plasma up to 48 h after administration.     

The effect of Epstein–Barr virus viremia on the progression to severe COVID-19

Epstein–Barr virus (EBV) is frequently reactivated by coronavirus 2019 (COVID-19), and a high incidence of EBV viremia has been reported in patients with severe COVID-19. However, the impact of EBV viremia on progression to severe COVID-19 is unclear. Therefore, we conducted a study to evaluate the effect of EBV on COVID-19 progression.We investigated EBV viremia at the time of admission in COVID-19 patients hospitalized between February 1, 2020, and April 11, 2021. A cross-sectional study was performed to compare the severity of COVID-19 according to the presence or absence of EBV viremia. However, since it is difficult to analyze the influence of EBV viremia on COVID-19 progression with cross-sectional studies, a retrospective cohort study, limited to patients with mild COVID-19, was additionally conducted to observe progression to severe COVID-19 according to the presence or absence of EBV viremia.Two hundred sixty-nine COVID-19 patients were tested for EBV viremia. In a cross-sectional study that included patients with both mild and severe COVID-19, the EBV viremia group had more severe pneumonia than the EBV-negative group. However, in the cohort study limited to mild cases (N = 213), EBV viremia was not associated with COVID-19 progression.COVID-19 severity may affect EBV viremia; however, there was no evidence that EBV viremia was a factor in exacerbating pneumonia in patients with mild COVID-19.     

The role of TRPV1 in the CD4+ T cell-mediated inflammatory response of allergic rhinitis

Transient receptor potential vanilloid 1 (TRPV1), which has been identified as a molecular target for the activation of sensory neurons by various painful stimuli, was reported to regulate the signaling and activation of CD4⁺ T cells. However, the role of TRPV1 in CD4⁺ T cell in allergic rhinitis remains poorly understood. In this study, TRPV1 expression was localized in CD4⁺ T cells. Both knockout and chemical inhibition of TRPV1 suppressed Th2/Th17 cytokine production in CD4 T cells and Jurkat T cells, respectively, and can suppress T cell receptor signaling pathways including NF-κB, MAP kinase, and NFAT. In TRPV1 knockout allergic rhinitis (AR) mice, eosinophil infiltration, Th2/Th17 cytokines in the nasal mucosa, and total and ova-specific IgE levels in serum decreased, compared with wild-type AR mice. The TRPV1 antagonists, BCTC or theobromine, showed similar inhibitory immunologic effects on AR mice models. In addition, the number of TRPV1⁺/CD4⁺ inflammatory cells increased in the nasal mucosa of patients with AR, compared with that of control subjects. Thus, TRPV1 activation on CD4⁺ T cells is involved in T cell receptor signaling, and it could be a novel therapeutic target in AR.     

Effect of a Chitosan Gel on Hemostasis and Prevention of Adhesion After Endoscopic Sinus Surgery

ObjectivesPostoperative bleeding and adhesion formation are the two most common complications after endoscopic sinus surgery (ESS). The former sometimes can be life threatening and the latter is the most common reason requiring revision surgery. This study was designed to evaluate the effect of newly developed chitosan gel (8% carboxymethyl chitosan, Surgi shield) on hemostasis and wound healing after ESS.MethodsA prospective, randomized, double-blind controlled trial was conducted in 33 patients undergoing symmetric ESS. At the conclusion of the operation, Surgi shield was randomly applied on one side of the nasal cavity, with the opposite side acting as control and the bleeding quantity of the surgical field was evaluated every 2 minutes. And then, Merocel was placed in the ethmoidectomized areas of the both sides. Five milliliters of Surgi shield was applied to the Merocel of intervention side and saline was applied to the other side. Merocel in both nasal cavities was removed and 5 mL of Surgi shield was applied again to the intervention side on the second day after surgery. The nasal cavity was examined using a nasal endoscope and the degree of adhesion, crusting, mucosal edema, infection, and granulations were graded at 1, 2, and 4 weeks after surgery.ResultsComplete hemostasis was rapidly achieved in the Surgi shield applied side compared with the control side at 2, 4, 6, 8, and 10 minutes after application of Surgi shield (P#x0003d;0.007, P#x0003d;0.004, P<0.001, P#x0003d;0.001, and P<0.001, respectively). There were significantly less adhesions on the Surgi shield applied side at postoperative 1, 2, and 4 weeks (P#x0003d;0.001, P<0.001, and P<0.001, respectively). The degree of mucosal edema, infection, crusting, or granulation formation assessed by the endoscopic features in the Surgi shield applied side was not significantly different from that of the control side (P>0.05). No adverse effects were noted in the patient series.ConclusionSurgi shield containing chitosan can be used safely to achieve rapid hemostasis immediately after ESS and to prevent adhesion formation.     

Application of ionic liquid to polymorphic transformation of anti-viral/HIV drug adefovir dipivoxil

Ionic liquids (ILs) are defined as salts with a melting point below 100 °C. ILs have received increasing attention as new alternative to organic solvents because of their unique physicochemical properties. Therefore, this study was conducted in the purpose to present the efficacy of ILs as new solvents capable to control the Polymorphic transformation phenomenon. Here, the polymorphic transformation phenomenon of adefovir dipivoxil, an efficient antiviral active pharmaceutical ingredient on human immunodeficiency virus, was investigated. The phase transformation phenomenon from the metastable polymorph, new form (NF) to the stable polymorph, Form-X in 1-allyl-3-ethylimidazolium tetrafluoroborate (AEImBF₄) and 1-butyl-2,3-dimethylimidazolium tetrafluoroborate (BDMImBF₄) ILs solutions was observed utilizing the solvent-mediated phase transformation method The thermodynamic factors, AEImBF₄/BDMImBF₄ solvent composition ratio of 3:7–6:4 and the temperature in range of 25–100 °C, as well as the dynamic factor, the rational speed in range of 300–1000 rpm were parameters studied in this experiment. The thermodynamic and dynamic equations involving nucleation and mass transfer were applied for the quantitative analysis. The result of the present study confirmed the use of ILs as substitute solvent for volatile organic solvents, and demonstrated the efficacy of ILs as potential solvent-media to control the polymorphic transformation.