Electrospun Structural Hybrids of Acyclovir-Polyacrylonitrile at Acyclovir for Modifying Drug Release

In traditional pharmaceutics, drug–crystalline nanoparticles and drug–polymer composites are frequently explored for their ability to modify drug release profiles. In this study, a novel sort of hybrid with a coating of acyclovir crystalline nanoparticles on acyclovir-polyacrylonitrile composites was fabricated using modified, coaxial electrospinning processes. The developed acyclovir-polyacrylonitrile at the acyclovir nanohybrids was loaded with various amounts of acyclovir, which could be realized simply by adjusting the sheath fluid flow rates. Compared with the electrospun composite nanofibers from a single-fluid blending process, the nanohybrids showed advantages of modifying the acyclovir release profiles in the following aspects: (1) the initial release amount was more accurately and intentionally controlled; (2) the later sustained release was nearer to a zero-order kinetic process; and (3) the release amounts at different stages could be easily allocated by the sheath fluid flow rate. X-ray diffraction results verified that the acyclovir nanoparticles were in a crystalline state, and Fourier-transform infrared spectra verified that the drug acyclovir and the polymer polyacrylonitrile had a good compatibility. The protocols reported here could pave the way for developing new types of functional nanostructures.

Microfluidic Fabrication of Helical Ca-Alginate Hydrogel Fibers

Helix is a sophisticated structure in nature and has many unique functions which makes it possible to store more information and energy, even receive more sensitive signals. Besides, as an effective method for preparing hydrogel fibers, microfluidic spinning has achieved unprecedented development in the past decade. However, hydrogel fiber with helical structure has began to be studied only in recent years. In this paper, the helical hydrogel fibers were prepared by the microfluidic spinning method. The microfluidic chip was assembled by PDMS connector, collection tube, inner and outer channels. Sodium alginate (SA) and calcium chloride were used as the core fluid and sheath fluid, respectively. By designing and adjusting the length of the chip, changing the concentration of SA and the ratio of two flow rates (inner flow rate/outer flow rate), a continuous and uniform helical hydrogel fiber was prepared. The relationships between the diameter of the fiber, the pitch of the helix and the concentration of SA, the ratio of two flow rates were discussed. The results showed that the diameter of the fiber was mainly affected by the core fluid. Within a certain range, as the concentration of SA increased, the diameter of the fiber increased. Besides, the pitch of the helix was greatly affected by the flow rate of sheath fluid. As the velocity of the sheath fluid increased, the pitch of the fiber increased. Such helical fiber could be used in micro sensors when added some conductive materials or crosslinked with some temperature responsive polymers such as N-isopropylacrylamide.

Correlation Between Posterior Tibialis Tendon Dysfunction with Ultrasonography and Adult Acquired Flatfoot Deformity with Radiographic X-ray and Feiss line in East Java’s Indonesian Professional Athletes

Background : Adult acquired flatfoot deformity (AAFD) is marked with a partial or complete flattening of the longitudinal medial arch that developed after maturity. AAFD, secondary to posterior tibialis tendon dysfunction (PTTD), is one of the most frequent foot and ankle pathologies in professional athletes. Different modality and procedures can be used to establish the diagnosis of AAFD and PTTD However, the correlation of these various clinical and imaging measurements with specific injuries of the PTT and supporting medial longitudinal arch structures has not been fully reported. The purpose of this study is to investigate the correlation between PTTD using ultrasonography and AAFD that diagnosed using both radiographic x-ray and feiss line examination.Method : 112 professional athletes with flat foot deformity on physical examination, symptom of PTT dysfunction such as medial ankle or foot pain, focal pain along the course of the PTT underwent foot radiographic x-ray using calcaneal inclination angle, ankle ultrasound to see PTT abnormality and feiss line examination using three degree of flat foot classification.Result : There were strong association between calcaneal inclination angle and PTTD includes the presence of PT tendon sheath fluid as well as tendon sheath thickening with p<0.05 with correlation coefficient (r) = 0.921 and 0.892 respectively. Weak association were also found between feiss line result and PT tendon sheath fluid as well as tendon sheath thickening with correlation coefficient (r) = 0.288 and 0.244. There were non significant association between calcaneal inclination and partial PT tendon tear as well as calcaneal inclination and feiss line result.Conclusion : A compressive understanding of posterior tibialis tendon dysfunction and flatfoot diagnosis will lead to more effective management in reducing the symptom.

SAT-074 A Rare Endocrine Cause of Pseudotumor Cerebri

Introduction: Idiopathic intracranial hypertension, also known as pseudotumor cerebri, can be associated with various medications, obesity, systemic conditions, and inherited disorders. To the best of our knowledge, this is the second pediatric case of a GnRH agonist reported to cause pseudotumor cerebri. Case presentation: Our patient, a 12 5/12-year-old transgender male (birth-assigned female), started depot leuprolide acetate to suppress puberty at 11 10/12 years of age (early Tanner 2 breast development). He received Lupron Depot® 7.5 mg intramuscularly for 4 doses, then 22.5 mg intramuscular every 13 weeks thereafter. Five months after his first injection, a routine eye examination revealed bilateral papilledema and enlarged blind spots, which was confirmed by a Pediatric Ophthalmologist. He was asymptomatic. There was no marked weight gain in the previous year with a BMI of 24.5 kg/m2 (+1.85 SD). His blood pressure was 110–123 mmHg systolic and 71–85 mmHg diastolic. Neurological examination was normal. CT head was normal. Cranial MRI showed slight flattening of the optic nerve heads, mild engorgement of optic nerve sheath fluid, and no space-occupying mass. Sedated lumbar puncture revealed elevated opening pressure of 31 cm H2O. CSF analysis, including pathology, was benign. He was managed with acetazolamide. Based on these findings, he was diagnosed with pseudotumor cerebri secondary to the GnRH agonist. Follow-up by the Ophthalmologist one month after starting acetazolamide showed significant improvement of the papilledema. Conclusion: This case highlights that patients on GnRH agonist therapy are at risk for pseudotumor cerebri, and we recommend periodic ophthalmologic surveillance.

The Relationships between Process Parameters and Polymeric Nanofibers Fabricated Using a Modified Coaxial Electrospinning

The concrete relationship between the process parameters and nanoproduct properties is an important challenge for applying nanotechnology to produce functional nanomaterials. In this study, the relationships between series of process parameters and the medicated nanofibers’ diameter were investigated. With an electrospinnable solution of hydroxypropyl methylcellulose (HPMC) and ketoprofen as the core fluid, four kinds of nanofibers were prepared with ethanol as a sheath fluid and under the variable applied voltages. Based on these nanofibers, a series of relationships between the process parameters and the nanofibers’ diameters (D) were disclosed, such as with the height of the Taylor cone (H, D = 125 + 363H), with the angle of the Taylor cone (α, D = 1576 − 19α), with the length of the straight fluid jet (L, D = 285 + 209L), and with the spreading angle of the instable region (θ, D = 2342 − 43θ). In vitro dissolution tests verified that the smaller the diameters, the faster ketoprofen (KET) was released from the HPMC nanofibers. These concrete process-property relationships should provide a way to achieve new knowledge about the electrostatic energy-fluid interactions, and to meanwhile improve researchers’ capability to optimize the coaxial process conditions to achieve the desired nanoproducts.

Analytical solutions for mass transport in hydrodynamic focusing by considering different diffusivities for sample and sheath flows

The fluid flow and mass transfer characteristics in two-dimensional hydrodynamic focusing are theoretically investigated by considering different physical properties for the sample and sheath flows. Adopting a single-domain formulation, which assigns the region variable physical properties, three-dimensional analytical solutions are obtained for species transport under hydrodynamically fully developed conditions. In addition, simplified analytical solutions are derived assuming a uniform velocity field appropriate to electrokinetic focusing. The results show that the normalized overall mean velocity is an increasing function of the height to width ratio and a decreasing function of the sheath to sample viscosity ratio. The dependence of this normalized mean velocity on the sheath to sample flow-rate ratio is, however, non-monotonic: it grows with the flow-rate ratio when the sample fluid is more viscous than the sheath fluid, whereas the opposite is true when the sheath fluid is more viscous. Moreover, although an increase in either the viscosity or flow-rate ratios results in creating a smaller value of the normalized focused width, varying the channel aspect ratio may lead to either thinner or thicker focused regions, depending on the viscosity ratio. The inspection of the mass transport characteristics reveals that only the viscosity ratio and the Péclet number can significantly alter the mixing length. Surprisingly, the minimum mixing length in the presence of significant axial diffusion is achieved for a single-phase flow. Finally, the dimensionless mixing length is reduced by increasing the Péclet number, although the changes are negligible when this parameter is above 10. This threshold is only true when the Péclet number is calculated based on the higher of the sample and sheath diffusion coefficients.

Posterior Tibial Tendon Dysfunction

Category: Hindfoot Introduction/Purpose: Stage 1 posterior tibial tendon dysfunction (PTTD) may be present without intra-substance tendon pathology. We hypothesize that in individuals with the clinical diagnosis of Stage 1 PTTD, with no MRI-detectable intra-substance tendon pathology, that sheath fluid amount is a confirmatory finding of PTTD. This purpose of this study was to quantify the amount of PTT sheath fluid in 1) individuals with the clinical diagnosis of Stage 1 PTTD and no MRI-detectable intra-substance tendon pathology and compare to controls with medial ankle pain (causes other) also without MRI-detectable intra-substance PTT pathology, and 2) test if there was a sheath fluid measurement predictive of the clinical diagnosis of PTTD. Methods: 326 individuals with medial ankle pain, no intra-substance PTT pathology, were studied, 48 with the clinical diagnosis of Stage 1 PTT dysfunction and 278 with medial ankle pain, causes other. Geometric methods defined MRI-based sheath fluid volume, maximum cross-sectional fluid area, and maximum fluid width. Fluid measurements were compared between groups and a predictive measurement calculated to identify individuals with PTTD. Measurement reliability was tested. Results: Individuals with PTT dysfunction had larger PTT sheath fluid volume, area, and width than controls (p’s < 0.001). An 9 mm threshold maximum fluid width was associated with PTTD (sensitivity 84%, specificity 85%). Measurements were reliable (p’s <0.03). Conclusion: The amount of PTT sheath fluid, in individuals with medial ankle pain and no intra-substance PTT pathology, was associated with Stage 1 PTTD and a maximum PTT sheath fluid width of > 9 mm predicted PTTD. This is clinically significance as MRI-detected sheath fluid can now be used as a confirmatory finding in individuals with the clinical diagnosis of Stage 1 PTTD who do not have MRI-detectable intra-substance pathology