Effects of Enteric-Coated Formulation of Sodium Bicarbonate on Bicarbonate Absorption and Gastrointestinal Discomfort.

Sodium bicarbonate is used as an ergogenic supplement to enhance people's performances in various exercises. This study aimed to evaluate the effects of intestinal delivery of sodium bicarbonate on bicarbonate absorption and associated side effects in an experimental human trial. After preparing and assessing enteric-coated and uncoated sodium bicarbonate tablet formulations, pharmacokinetic analysis and gastrointestinal symptom tests were performed after oral administration in the human body. The dose required to increase blood bicarbonate concentration over 5 mmol∙L-1 for the purpose of improving performance during high-intensity exercise was also determined. Enteric-coated tablet formulation protects sodium bicarbonate under acidic conditions and releases bicarbonate in the intestine. Enteric-coated tablet formulation also reduced the oral dose required to achieve a blood bicarbonate concentration over 5 mmol∙L-1 from 300 mg∙kg-1 of uncoated tablet formulation to 225 mg∙kg-1. Gastrointestinal discomfort was significantly decreased for the group given 225 mg∙kg-1 enteric-coated tablets compared to that given 300 mg∙kg-1 uncoated tablets. These results suggest that enteric-coated tablet formulation could reduce the oral dose required in order to achieve a blood bicarbonate concentration over 5 mmol∙L-1 by 25%, from 300 mg∙kg-1 to 225 mg∙kg-1, along with its ability to reduce gastrointestinal discomfort associated with the dosage.

Handheld microfocused ultrasound device for facial lifting: A preliminary study of ULTIGHT.

OBJECTIVE: Although focused ultrasound modalities have achieved positive clinical results in noninvasive skin rejuvenation, they presented various side effects and particularly severe pain during treatment. This study introduces a microfocused ultrasound (MFU) device, ULTIGHT, to overcome the severe pain issue, providing quasi-facial lifting. MATERIALS AND METHODS: Transducer surface was imaged with a scanning electron microscope. The energies of four treatment cartridges were measured using an ultrasound power meter. In vitro experiments were performed to quantitatively evaluate the MFU thermal zones (MFUTZs) and treatment line (TL) of 10 MFUTZs. Ex vivo experiments were performed to evaluate the MFUTZs and temperature rise in tissue. Clinical trials using eight volunteers were performed to qualitatively evaluate facial lifting. RESULTS: The MFU transducer clearly showed a smooth and no air gap surface. ULTIGHT produced 10 discrete MFUTZs in a TL of length 10 mm. In ex vivo tissue, discrete linear MFUTZs were clearly observed at lower number of TLs; however, they started to aggregate at higher number of TLs. The temperature rise was linearly increased as a function of the number of treatments. A single MFUTZ resulted in a temperature rise of 3°C-10°C that could cause hyperthermia for body temperature. In the clinical trials, the volunteers showed quasi-facial lifting right after treatment on the lower facial region. CONCLUSIONS: ULTIGHT provides relatively low energy, which may be advantageous or disadvantageous depending on clinical applications. Additionally, it has the advantage of being pain-free even without anesthetic during treatment, providing quasi-facial lifting right after treatment.

Development of a Customized Endoscopic Dual-Diffusing Optical Fiber Probe for Pancreatic Cancer Therapy: Toward Clinical Use.

Objective: We developed a dual-diffusing optical fiber probe (DDOFP), capable of uniformly illuminating the anatomical structure of pancreatic duct for photodynamic therapy (PDT) of pancreatic cancer in clinical settings. Background: Optical fiber presents a unique route for pancreatic PDT by enabling access to the pancreatic duct. For effective pancreatic PDT, the optical fiber should produce a uniform illumination covering of the pancreatic duct, while maintaining its transmission property under thermomechanical stresses in surgical environments. Methods: The transmission profiles of DDOFP were measured using a charge-coupled device (CCD) camera at two directions: front-spherical and side-cylindrical areas of the optical fiber. We simulated the change in transmission property by curved tube structures using optically transparent phantom. DDOFP was integrated with 19-gauge needle catheter that is commercially used as an optical guide to treat pancreatic cancer. The temperature of DDOFP was measured at the end face using a thermistor probe in the bovine tissue, while delivering laser energy of over 200 and 500 J. Results: DDOFP was customized to secure the inner diameter of the 19-gauge needle catheter of 686 µm to be integrated as a clinical device. The round ball lens fiber tip minimized the back-burn effect caused by blood carbonization during surgery and induced front-spherical diffusion. DDOFP produced uniform light illumination with intensity difference of <10%. When DDOFP was bent with a small curvature <15 mm, the transmission intensity was consistent. Under high-power laser transmission, DDOFP was found to be robust to cracking or deformation. Conclusions: DDOFP was customized for pancreatic PDT with superior thermomechanical property and uniform light illumination at both the front-spherical and side-cylindrical areas. This is the smallest clinically available optical fiber per our knowledge and officially approved by the Korea Food and Drug Administration (item approval number: 17-516). DDOFP can contribute immensely toward the efficient delivery of pancreatic PDT and photothermal therapy.