Efficacy and Safety of Ultrasound-Guided Radiofrequency Ablation for Primary Hyperparathyroidism: A Prospective Study

Objective@#To assess the efficacy and safety of ultrasound (US)-guided radiofrequency ablation (RFA) in patients with primary hyperparathyroidism (PHPT). @*Materials and Methods@#This prospective study enrolled 39 participants (14 male, 25 female; mean age, 59.5 ± 15.3 [range, 18–87] years) between September 1, 2018, and January 31, 2021. All participants had parathyroid lesions causing PHPT, proven biochemically and through imaging. The imaging features of the PHPT nodules, including the shape, margin, size, composition, and location, were evaluated before treatment. Serum intact parathyroid hormone, calcium, and phosphorus levels; parathyroid nodule volume; and PHPT-related symptoms were recorded before and after treatment. We calculated the technical success, biochemical cure, and clinical cure rates for these patients. Complications were evaluated during and after the ablation. @*Results@#Complete ablation was achieved in 38 of the 39 nodules in the 39 enrolled participants. All the patients were treated in one session. The technical success rate was 97.4% (38/39). The mean follow-up duration was 13.2 ± 4.6 (range, 6.0–24.9) months. At 6 and 12 months post-RFA, the biochemical cure rates were 82.1% (32/39) and 84.4% (27/32), respectively, and the clinical cure rates were 100% (39/39) and 96.9% (31/32), respectively. Only 2.6% (1/39) of the patients had recurrent PHPT. At 1, 3, 6, and 12 months after technically successful RFA, 44.7% (17/38), 34.3% (12/35), 15.8% (6/38), and 12.5% (4/32) of participants, respectively, had elevated eucalcemic parathyroid hormone levels. Recurrent laryngeal nerve paralysis occurred in 5.1% (2/39) of the patients, who recovered spontaneously within 1–3 months. @*Conclusion@#US-guided RFA was effective and safe for PHPT patients. RFA may be an alternative treatment tool for patients who cannot tolerate or refuse to undergo surgery.

In vitro dexamethasone release from nanoparticles and its pharmacokinetics in the inner ear after administration of the drug-loaded nanoparticles via the round window / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the feasibility of local drug delivery into the inner ear using solid lipid nanoparticles (SLN) and evaluate its potential for inner ear disease treatment in terms of the pharmacokinetics of the delivered drug in the inner ear.</p><p><b>METHODS</b>Dexamethasone acetate (DA)-loaded SLN was prepared with Compritol 888 ATO as the matrix by means of hot dispersion-ultrasonic technique. A high-performance liquid chromatography (HPLC) was established for determining DA and dexamethasone (Dex). The pharmaceutical properties of DA-loaded SLN including the particle size, entrapment ratio and in vitro release were estimated. DA-loaded SLN was administered via intratympanic injection or intravenous injection in guinea pigs and Dex concentration in the perilymph was measured with HPLC for estimation of the pharmacokinetic parameters.</p><p><b>RESULTS</b>The mean diameter of the DA-loaded SLN was 106.8 nm with entrapment ratio of 83.8%, and the in vitro DA release from the nanoparticles well conformed to Weibull distribution, with sustained-release of DA from the SLN exceeding 6 days. After intravenous injection of DA-loaded SLN in guinea pigs, Dex failed to be detected in the perilymph. Compared with Dex-loaded in situ gel following intratympanic injection, the relative bioavailability of Dex in the perilymph was 504% following intratympanic injection of DA-loaded SLN, which also resulted in increased t(1/2) and mean residence time (MRT) by 0.5 and 1.9 folds respectively.</p><p><b>CONCLUSION</b>Nanoparticles can be a promising tympanic drug delivery system for topical drug administration in the treatment of inner ear diseases.</p>

Effect of receptor solution specific conductivity on iontophoresis of tetracaine hydrochloride / 药学学报

<p><b>AIM</b>To examine the quantitative relationship between solution specific conductivity and the permeability of tetracaine HCl, and to investigate the effect of receptor solution specific conductivity on the iontophoretic transport.</p><p><b>METHODS</b>An in vitro study was carried out to determine the iontophoretic permeability of tetracaine hydrochloride through rat skin. Iontophoretic flux of tetracaine hydrochloride through excised rat skin was determined using Valia-Chien two-chamber diffusion cells with a constant d.c. current and Ag/AgCl electrodes. The specific conductivities of donor and receptor solution were also measured.</p><p><b>RESULTS</b>Iontophoretic flux of tetracaine hydrochloride increased with a decrease of anion (chloride ion) concentration in receptor. And the iontophoretic permeability (ER, ER is the enhancement ratio, and ER = iontophoretic flux/passive flux) for tetracaine hydrochloride was directly related to the conductivity of receptor solution when other conditions were held constant. Linear regressions confirmed that ER was related to inverse of overall specific conductivity of donor and receptor solution [1/(ks.d + ks.r), ks.d and ks.r are the specific conductivity of donor and receptor solution].</p><p><b>CONCLUSION</b>The results suggest that specific conductivity of receptor solution may be a important factor for the iontophoretic permeability of a solute.</p>

Preparation of interferon-alpha-containing liposomes by the powder bed grinding method / 浙江大学学报·医学版

OBJECTIVE: To investigate a nwe, simple technique for preparation of interferon-alpha-liposomes, which may be suitable for industrial use. METHODS The uniform design coupled with computerized optimization was utilized to screen the formulation and preparation procedure of interferon-alpha-liposomes. Pro-liposomes were prepared by the powder bed grinding method and combined with interferon-alpha-solution to form interferon-alpha-liposomes. Liposome size was determined by the particle size analyzer. Free interferon-alpha and interferon-alpha-liposome were separated by gel filtration. Then the recovered activity of interferon-alpha was analyzed by enzyme-linked immunosorbent assay. RESULTS The result demonstrated that the best interferon-alpha-liposome formulation was as follows: the protectant was sorbitol; weight ratio of protectant to lipid was 5:1; weight ratio of octadecytamin to lipid was 1:9; weight ratio of sobey phosphatidylcholine to cholesterol was 9:1 respectively. Interferon-alpha-liposome size determined by the particle size analyzer was 80.8+/-36 nm and the encapsulation efficiency was 59.0+/-3.3%. CONCLUSION The powder bed grinding method can be used to prepare pro-liposomes which can be easily combined with interferon-alpha-solution to form interferon-alpha-liposomes.