Evaluation of Biological Equivalence for Generic Tulathromycin Injections in Cattle.

The recent expiration of patents for the antibiotic tulathromycin has led to a significant increase in the number of generic tulathromycin products (GTPs) available. This study aims to evaluate the bioequivalence of four GTPs, which experienced a rapid increase in market share. The bioequivalence was evaluated by performing pharmacokinetic assessments. The four selected GTPs (Tulaject, Tulagen, Toulashot, and T-raxxin) were compared with the reference product, Draxxin. A dose of 2.5 mg/kg.bw/day was administered via subcutaneous injection, and blood samples were collected 460 times from 20 Holstein cattle. Plasma concentrations of tulathromycin were measured over time using LC-MS/MS analysis. Bioequivalence was evaluated using a statistical program for pharmacokinetic parameters, including the area under the concentration time curve (AUC) and the maximum plasma concentration (Cmax). The bioequivalence was considered proven if the difference between the test and reference products was within 20% for both AUC and Cmax. The results showed that the confidence interval (CI, 90%) for both AUC and Cmax values was within the 80~120% range, demonstrating the bioequivalence of the four GTPs compared to Draxxin. This study provides evidence for the bioequivalence of the selected GTPs, contributing to their validation for use as effective antibiotics.

Fabry-Perot Interferometric Fiber-Optic Sensor for Rapid and Accurate Thrombus Detection.

We present a fiber-optic sensor based on the principles of a Fabry-Perot interferometer (FPI), which promptly, sensitively, and precisely detects blood clot formation. This sensor has two types of sensor tips; the first was crafted by splicing a tapered fiber into a single-mode fiber (SMF), where fine-tuning was achieved by adjusting the tapered diameter and length. The second type is an ultra-compact blood FPI situated on the core of a single-mode fiber. The sensor performance was evaluated via clot-formation-indicating spectrum shifts induced by the varied quantities of a thrombin reagent introduced into the blood. The most remarkable spectral sensitivity of the micro-tip fiber type was approximately 7 nm/µL, with a power sensitivity of 4.1 dB/µL, obtained with a taper fiber diameter and length of 55 and 300 µm, respectively. For the SMF type, spectral sensitivity was observed to be 8.7 nm/µL, with an optical power sensitivity of 0.4 dB/µL. This pioneering fiber-optic thrombosis sensor has the potential for in situ applications, healthcare, medical monitoring, harsh environments, and chemical and biological sensing. The study underscores the scope of optical technology in thrombus detection, establishing a platform for future medical research and application.

A laser-driven optical atomizer: photothermal generation and transport of zeptoliter-droplets along a carbon nanotube deposited hollow optical fiber.

From mechanical syringes to electric field-assisted injection devices, precise control of liquid droplet generation has been sought after, and the present state-of-the-art technologies have provided droplets ranging from nanoliter to subpicoliter volume sizes. In this study, we present a new laser-driven method to generate liquid droplets with a zeptoliter volume, breaking the fundamental limits of previous studies. We guided an infrared laser beam through a hollow optical fiber (HOF) with a ring core whose end facet was coated with single-walled carbon nanotubes. The laser light was absorbed by this nanotube film and efficiently generated a highly localized microring heat source. This evaporated the liquid inside the HOF, which rapidly recondensed into zeptoliter droplets in the surrounding air at room temperature. We spectroscopically confirmed the chemical structures of the liquid precursor maintained in the droplets by atomizing dye-dissolved glycerol. Moreover, we explain the fundamental physical principles as well as functionalities of the optical atomizer and perform a detailed characterization of the droplets. Our approach has strong prospects for nanoscale delivery of biochemical substances in minuscule zeptoliter volumes.

Efficacy and safety of eltrombopag in adult refractory immune thrombocytopenia.

BACKGROUND: Eltrombopag is a thrombopoietin receptor agonist with excellent treatment outcomes in immune thrombocytopenia (ITP). Here, we analyzed the dose of eltrombopag required to achieve and maintain safe platelet counts in Korean ITP patients. METHODS: Adult refractory ITP patients (<30,000 platelets/µL) were enrolled. Eltrombopag doses were increased to achieve a target platelet count (≥50,000 cells/µL). After achieving the target platelet count, the dose of concomitant ITP medications and eltrombopag was reduced to identify the lowest effective dose required to maintain the platelet count. RESULTS: Among 18 patients, 66.7% achieved complete response, 5.6% achieved platelet counts between 50,000 and 100,000 cells/µL, and 27.8% failed to achieve the target platelet count. The median ITP duration was significantly shorter in patients who achieved the target platelet count. The initial dose required to achieve the target platelet count was 25 mg/d. The adjusted maintenance doses were 25 mg twice per week or 25 mg/d. After discontinuation, 83.3% relapsed, and the median relapse-free survival was 15 days. Two relapsed and 1 failed patient switched to romiplostim. The response to romiplostim was similar to eltrombopag. During eltrombopag treatment, 38.9% showed hepatobiliary laboratory anomalies. Among 9 follow-up bone marrow examinations, 1 revealed fibrosis after 1 year of treatment. CONCLUSION: Eltrombopag was well tolerated with excellent treatment outcomes in refractory adult ITP patients. Low-dose eltrombopag effectively maintained the target platelet count. However, some patients required longer or higher-dose treatment to maintain the target platelet count, especially in heavily pretreated or longer ITP cases.

Characteristics of a tapered undulator for the X-ray absorption fine-structure technique at PLS-II.

An in-vacuum undulator (IVU) with a tapered configuration was installed in the 8C nanoprobe/XAFS beamlime (BL8C) of the Pohang Light Source in Korea for hard X-ray nanoprobe and X-ray absorption fine-structure (XAFS) experiments. It has been operated in planar mode for the nanoprobe experiments, while gap-scan and tapered modes have been used alternatively for XAFS experiments. To examine the features of the BL8C IVU for XAFS experiments, spectral distributions were obtained theoretically and experimentally as functions of the gap and gap taper. Beam profiles at a cross section of the X-ray beam were acquired using a slit to visualize the intensity distributions which depend on the gap, degree of tapering and harmonic energies. To demonstrate the effect of tapering around the lower limit of the third-harmonic energy, V K-edge XAFS spectra were obtained in each mode. Owing to the large X-ray intensity variation around this energy, XAFS spectra of the planar and gap-scan modes show considerable spectral distortions in comparison with the tapered mode. This indicates that the tapered mode, owing to the smooth X-ray intensity profile at the expense of the highest and most stable intensity, can be an alternative for XAFS experiments where the gap-scan mode gives a considerable intensity variation; it is also suitable for quick-XAFS scanning.

OCT-1, ABCB1, and ABCG2 Expression in Imatinib-Resistant Chronic Myeloid Leukemia Treated with Dasatinib or Nilotinib.

This study explored drug transporter expression levels and their impact on clinical response to imatinib and second-generation tyrosine kinase inhibitors (TKIs) in imatinib- resistant chronic myeloid leukemia (CML). Imatinib-resistant chronic phase CML patients treated with dasatinib (n=10) and nilotinib (n=12) were enrolled. The mRNA expression of the OCT-1, ABCG2, and ABCB1 genes was quantified by using paired bone marrow samples obtained before administering imatinib and at the point of detecting imatinib resistance (just before starting second-generation TKIs). The expression levels of OCT-1 and ABCG2 were lower in follow-up than in imatinib-naïve samples. ABCB1 revealed highly variable expression levels before and after imatinib treatment. In addition, median ABCB1 expression in follow-up samples was lower in patients achieving complete cytogenetic response or major molecular response during imatinib treatment than in failed patients. Higher ABCG2 expression in imatinib-exposed samples showed a negative impact on optimal response to dasatinib. Patients with higher ABCG2 expression in imatinib-exposed samples also had shorter progression- free survival with dasatinib treatment. However, no significant correlation was found between these drug transporter expression levels in imatinib-naïve or imatinib- exposed samples and responses to nilotinib. In imatinib-resistant CML, OCT-1 and ABCG2 mRNA expression decreased after imatinib treatment. Patients with higher ABCG2 expression in imatinib-exposed samples showed poor treatment outcome with dasatinib. On the other hand, a higher expression level of ABCB1 in imatinib-exposed samples did not affect second-generation TKI responses but was correlated with poor imatinib responses.

Photovoltaic and thermal properties of electrolytes based on electrospun poly(vinylidene fluoride-hexafluoro propylene)/poly(methyl methacrylate) nanofibers for dye-sensitized solar cells.

We prepared electrospun polymer nanofibers by electrospnning method and investigated about their applications to dye-sensitized solar cells (DSSCs). Electrospun polymer nanofibers applied to the polymer matrix in electrolyte for DSSCs. To improve the stiffness of polymer nanofiber, poly(vinylidene fluoride-hexafluoro propylene)/Poly(methyl methacrylate) (PVDF-HFP/PMMA) blend nanofibers were prepared and examined. In the electrospun PVDF-HFP/PMMA (1:1) blend nanofibers, the best results of VOC, JSC, FF, and efficiency of the DSSC devices showed 0.71 V, 12.8 mA/cm2, 0.61, and 5.56% under AM 1.5 illumination.

The reliability and validity of the korean version of the child sexual behavior inventory.

OBJECTIVE: This study examined the reliability and validity of the Korean version of the Child Sexual Behavior Inventory (CSBI) in Korean children aged from 6 to 12 years old and the suitability of and potential for clinical application of the CSBI in Korean population. METHODS: The participants consisted of 158 typically growing children and 122 sexually abused children. The subjects were evaluated using the Korean version of the Child Sexual Behavior Inventory (CSBI), the Child Behavior Checklist (CBCL), and the Trauma Symptom Checklist for Young Children (TSCYC). Internal consistency was examined as a measure of reliability. To investigate the concurrent validity, Pearson's correlations were calculated. One-way ANCOVA was used to demonstrate discriminant validity. RESULTS: The Cronbach's α value was 0.84. The CSBI total score was moderately correlated with the CBCL subscales and mildly correlated with the sexual concern subscale of the TSCYC. The total score of the CSBI for the sexually abused children group was significantly higher than that of typically growing children group. CONCLUSION: This study demonstrated that the Korean version of the Child Sexual Abuse Inventory (CSBI) is a reliable and valid tool. It can be applied in the clinical field for assessing the sexual behavior of Korean children aged from 6 to 12 who are suspected to have been sexually abused.

Effect of nano sized silver on electrospun nylon-6 fiber.

We incorporated silver nanoparticles into a nylon solution, fabricated electrospun nanofibers, and studied various parameters of the electrospun fibers. We found that the addition of silver nanoparticles introduces antibacterial effects into nylon composite fibers. The average fiber diameter and fiber morphology was greatly affected when parameters such as solution concentration and the amount of silver nanoparticles were changed. The composite fibers that we prepared have the potential to be used as filtration membranes.

Electrospun nano composites of poly(vinyl pyrrolidone)/ nano-silver for antibacterial materials.

Poly(vinyl pyrrolidone) (PVP) and nanosilver are promising candidates for biomedical applications because of their biocompatibility and antibacterial efficacy, respectively. In this research, three kinds of nanosilver particles (NSPs) were prepared using the seed mediate growth method and added to electrospinning solutions. PVP/NSPs composites were prepared by electrospinning of 10 wt% PVP solutions that contained NSPs in ethanol. The electrospinability of PVP/NSPs nanowebs in ethanol was investigated according to three different concentrations of NSPs. The Electrospun PVP/NSPs nanocomposites were photocross-linked to improve their water stability. The antibacterial efficacy of the PVP/NSPs nanocomposites was assessed against three types of bacteria; Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli. The photocross-linked PVP/NSPs nanocomposites had high water stability and significant antibacterial efficacy against all three types of bacteria. Therefore, these composites could be applied as antimicrobial materials.

Fabrication of biodegradable nanofibers of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) via electrospinning.

For the first time, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) nanofibrous membrane has been fabricated via electrospinning method. To improve the electrospinnability and reduce the diameter of fibers, the solvent and salt additives were used that affected on the parameters including such as the viscosity and the conductivity of the electrospinning solution for poly(3-hydroxybutyrate-co-3-hydroxyhexanoate). Since the additional salts should be removed, it could be inferred that the co-solvent system was predominant to prepare the nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) membrane. This biodegradable nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) membrane has a great potential to be used in the various application fields such as tissue engineering, implants, packaging materials, agriculture, and so on.

Preparation of biodegradable polymer/silver nanoparticles composite and its antibacterial efficacy.

Biodegradable poly(ethylene oxide) nanofibers containing silver nanoparticles were successfully prepared by the electrospinning without the further reduction process which could cause the damages of nanofibers. Transmission electron microscopy showed that the silver nanoparticles were dispersed in poly(ethylene oxide) nanofibers without aggregation. This facile process would be the effective method to prepare the silver nanoparticles/polymer nanocomposites. Moreover, the silver nanoparticles embedded in the poly(ethylene oxide) nanofibers were responsible for the antibacterial activities against Staphylococcus aureus and Klebsiella pneumoniae, respectively. Therefore, it is expected that the silver nanoparticles/poly(ethylene oxide) nanocomposites can be used for practical applications as the biomaterial.

Alpha neurofeedback improves the maintaining ability of alpha activity.

The effects of alpha-neurofeedback (ANF) on electroencephalographic alpha-activity were investigated. Each session consisted of a 2.5-min eye-opened state and 17.5-min of ANF, which was divided into 16 1.25-min bins. Alpha amplitudes were gradually increased as the session was repeated. The maximum value at the start of ANF gradually decreased as time passed, but the slowdown of alpha-activity during each session was decreased as the session was repeated. The correlation between alpha-activity at the end of ANF and at the following session's eye-opened state was highly significant. These results showed that ANF enhances the ability of alpha-activity to maintain itself rather than the increase of alpha-amplitude during intrasession and that the maintained alpha-activity during former training remained until the next session.