Development of an effective sample transfer device for biomarker detection in nasal secretions.

Nasal secretions (NS) reflect inflammatory activity of the nasal mucosa and thus can be utilized for disease diagnosis and determining treatment effects in Allergic rhinitis (AR). However, non-standardized collection of samples can affect the measured concentration of inflammatory biomarker in NS. In this study, we aimed to develop and evaluate new devices capable of standardizing the collection, storage, and preprocessing methods of NS samples. First, we chose the best swab as polyester (PE) and selected a stimulation method, twirling for 10 s at 1 Hz, to efficiently release AR biomarkers from a PE swab. Storage of sample solutions at -20 °C was optimal for the stability of biomarkers for the detection of AR. The new swab sample transfer device showed excellent concentration recovery efficiency (90-100%) for tryptase (Trp) and eosinophil cationic protein (ECP) without crosstalk between the two biomarkers. Finally, we compared the concentration of Trp in human NS samples of AR patients (n = 6) pre-processed by the new device with that by centrifuge as a standard method. As a result, the concentrations of Trp in NS were very similar in both groups. Therefore, this device can be utilized as an effective sample transfer and pre-processing device for point-of-care testing of AR.

Low-Cost Label-Free Biosensing Bimetallic Cellulose Strip with SILAR-Synthesized Silver Core-Gold Shell Nanoparticle Structures.

We introduce a label-free biosensing cellulose strip sensor with surface-enhanced Raman spectroscopy (SERS)-encoded bimetallic core@shell nanoparticles. Bimetallic nanoparticles consisting of a synthesis of core Ag nanoparticles (AgNP) and a synthesis of shell gold nanoparticles (AuNPs) were fabricated on a cellulose substrate by two-stage successive ionic layer absorption and reaction (SILAR) techniques. The bimetallic nanoparticle-enhanced localized surface plasmon resonance (LSPR) effects were theoretically verified by computational calculations with finite element models of optimized bimetallic nanoparticles interacting with an incident laser source. Well-dispersed raspberry-like bimetallic nanoparticles with highly polycrystalline structure were confirmed through X-ray and electron analyses despite ionic reaction synthesis. The stability against silver oxidation and high sensitivity with superior SERS enhancement factor (EF) of the low-cost SERS-encoded cellulose strip, which achieved 3.98 × 108 SERS-EF, 6.1%-RSD reproducibility, and <10%-degraded sustainability, implicated the possibility of practical applications in high analytical screening methods, such as single-molecule detection. The remarkable sensitivity and selectivity of this bimetallic biosensing strip in determining aquatic toxicities for prohibited drugs, such as aniline, sodium azide, and malachite green, as well as monitoring the breast cancer progression for urine, confirmed its potential as a low-cost label-free point-of-care test chip for the early diagnosis of human diseases.

Liposomal melatonin rescues methamphetamine-elicited mitochondrial burdens, pro-apoptosis, and dopaminergic degeneration through the inhibition PKCδ gene.

We have demonstrated that mitochondrial oxidative damage and PKCδ overexpression contribute to methamphetamine-induced dopaminergic degeneration. Although it is recognized that antioxidant melatonin is effective in preventing neurotoxicity induced by methamphetamine, its precise mechanism remains elusive. C57BL/6J wild-type mice exhibited a similar degree of dopaminergic deficit when methamphetamine was administered during light and dark phases. Furthermore, dopaminergic neuroprotection by genetic inhibition of PKCδ during the light phase was comparable to that during the dark phase. Thus, we have focused on the light phase to examine whether melatonin modulates PKCδ-mediated neurotoxic signaling after multiple high doses of methamphetamine. To enhance the bioavailability of melatonin, we applied liposomal melatonin. Treatment with methamphetamine resulted in hyperthermia, mitochondrial translocation of PKCδ, oxidative damage (mitochondria > cytosol), mitochondrial dysfunction, pro-apoptotic changes, ultrastructural mitochondrial degeneration, dopaminergic degeneration, and behavioral impairment in wild-type mice. Treatment with liposomal melatonin resulted in a dose-dependent attenuation against degenerative changes induced by methamphetamine in wild-type mice. Attenuation by liposomal melatonin might be comparable to that by genetic inhibition (using PKCδ((-/-)) mice or PKCδ antisense oligonucleotide). However, liposomal melatonin did not show any additional protective effects on the attenuation by genetic inhibition of PKCδ. Our results suggest that the circadian cycle cannot be a key factor in modulating methamphetamine toxicity under the current experimental condition and that PKCδ is one of the critical target genes for melatonin-mediated protective effects against mitochondrial burdens (dysfunction), oxidative stress, pro-apoptosis, and dopaminergic degeneration induced by methamphetamine.

Optimization of HPLCCAD method for simultaneous analysis of different lipids in lipid nanoparticles with analytical QbD.

Since lipid nanoparticles (LNP) have emerged as a potent drug delivery system, the objective of this study was to develop and optimize a robust high-performance liquid chromatography with charged aerosol detectors (HPLCCAD) method to simultaneously quantify different lipids in LNPs using the analytical quality by design (AQbD) approach. After defining analytical target profile (ATP), critical method attributes (CMAs) were established as a resolution between the closely eluting lipid peaks and the total analysis time. Thus, potential high-risk method parameters were identified through the initial risk assessment. These parameters were screened using Plackett-Burman design, and three critical method parameters (CMPs)-MeOH ratio, flow rate, and column temperature-were selected for further optimization. Box-Behnken design was employed to develop the quadratic models that explain the relationship between the CMPs and CMAs and to determine the optimal operating conditions. Moreover, to ensure the robustness of the developed method, a method operable design region (MODR) was established using the Monte Carlo simulation. The MODR was identified within the probability map, where the risk of failure to achieve the desired CMAs was less than 1%. The optimized method was validated according to the ICH guidelines (linearity: R2 > 0.995, accuracy: 97.15-100.48% recovery, precision: RSD < 5%) and successfully applied for the analysis of the lipid in the LNP samples. The development of the analytical method to quantify the lipids is essential for the formulation development and quality control of LNP-based drugs since the potency of LNPs is significantly dependent on the compositions and contents of the lipids in the formation.

Replacement of microglial cells using Clodronate liposome and bone marrow transplantation in the central nervous system of SOD1(G93A) transgenic mice as an in vivo model of amyotrophic lateral sclerosis.

Disease progression of amyotrophic lateral sclerosis (ALS) is partially mediated by the toxic microenvironment established by microglia. In the present study, we used SOD1G93A transgenic mice as an in vivo ALS model and replaced microglia expressing mutant SOD1 (mSOD1) with microglia expressing wild-type SOD1 (w/tSOD1) to modulate the toxic microenvironment. Stereotactic injection of Clodronate liposome, a selective toxin against the monocyte/macrophage system, into the fourth ventricle of the brains of 12-week-old asymptomatic ALS mice reduced the number of microglia effectively in the central nervous system. Subsequent bone marrow transplantation (BMT) with bone marrow cells (BMCs) expressing w/tSOD1 and GFP leads to replacement of the endogenous microglia of the ALS mice with microglia expressing w/tSOD1 and GFP. The expression of mSOD1 in the other neural cells was not influenced by the replacement procedures, and immunological side effects were not observed. The replacement of microglia significantly slowed disease progression and prolonged survival of the ALS mice compared with the ALS mice treated by stereotactic injection of PBS-liposome and BMT with BMCs expressing mSOD1 or w/tSOD1. These results suggest that replacement of microglia would improve the neural cell microenvironment, thereby slowing disease progression. The mechanisms and functional implications of this replacement require further elucidation.

3D-printed tablets using a single-step hot-melt pneumatic process for poorly soluble drugs.

Main purpose was to evaluate the applicability of a 3D-printer equipped with a hot-melt pneumatic dispenser as a single-step process to prepare tablet dosage forms. Dutasteride, a poorly water-soluble drug, was selected as a model drug. Soluplus®, Kollidon® VA 64, Eudragit® E PO, and hydroxypropyl cellulose (HPC) were premixed as bulking agents prior to printing. Differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA) were utilized to evaluate the physicochemical properties of the 3D-printed tablets. Moreover, different geometries were designed to correlate the surface area/volume (SA/V) of the tablets with respect to their release profiles. As a result, printed dutasteride was confirmed to be in an amorphous state and not recrystallized even after the accelerated storage stability. Out of the four bulking agents, Kollidon® VA 64, enhanced the dissolution of the printed dutasteride, reaching above 80% within 15 min. These results suggest that the hot-melt pneumatic dispenser was efficient in converting the solid state into an amorphous state, which significantly enhanced the dissolution. On the other hand, the tube-shaped 3D-printed tablet exhibited the fastest drug dissolution profile, which had the highest SA/V ratio in comparison to the cube, hemisphere, and pyramid shapes. These results confirm the dependency of the drug dissolution rate not only on its crystallinity but also on the surface area of the 3D-printed tablet. Therefore, a 3D-printer equipped with a hot-melt pneumatic dispenser possesses useful applicability in enhancing drug dissolution, especially for poorly water-soluble drugs, in a single-step process.

In vitro dynamic degradation behavior of new magnesium alloy for orthopedic applications.

We report on methodologies for use in the design of a biodegradable Mg alloy appropriate for load-bearing but temporary orthopedic implant applications. Comparative studies of Mg-5Ca and Mg-5Ca-1Zn were conducted to explore the effects of a combination of minor alloying and hot extrusion, on the alloy's mechanical properties and corrosion resistance. The extruded Mg-5Ca-1Zn exhibited high ultimate compressive strength of 385 MPa and suffered no significant structural degradation even after immersion in simulated body fluid for 30 days. Mg-5Ca-1Zn alloy showed the mechanical strength and controlled corrosion rate to be considered as an ideal candidate for biodegradable orthopedic implant material.

Disparities in health care access and receipt of preventive services by disability type: analysis of the medical expenditure panel survey.

OBJECTIVE: To examine differences in access to health care and receipt of clinical preventive services by type of disability among working-age adults with disabilities. DATA SOURCE: Secondary analysis of Medical Expenditure Panel Survey (MEPS) data from 2002 to 2008. STUDY DESIGN: We conducted cross-sectional logistic regression analyses comparing people with different types of disabilities on health insurance status and type; presence of a usual source of health care; delayed or forgone care; and receipt of dental checkups and cancer screening. DATA COLLECTION: We pooled annualized MEPS data files across years. Our analytic sample consisted of adults (18-64 years) with physical, sensory, or cognitive disabilities and nonmissing data for all variables of interest. PRINCIPAL FINDINGS: Individuals with hearing impairment had better health care access and receipt than people with other disability types. People with multiple types of limitations were especially likely to have health care access problems and unmet health care needs. CONCLUSIONS: There are differences in health care access and receipt of preventive care depending on what type of disability people have. More in-depth research is needed to identify specific causes of these disparities and assess interventions to address health care barriers for particular disability groups.

Amino acid-bearing ROMP polymers with a stereoregular backbone.

The ruthenium-catalyzed ring-opening polymerization (ROMP) of 1-cyclobutenecarbonyl glycine methyl ester provides translationally invariant, head-to-tail ordered polymers. This polybutadiene backbone contains (within the limits of detection) only E-trisubstituted olefins, and it has no stereocenters that would serve as a source of structural ambiguities. Characterization of the polymer products indicates that they have polydispersities ranging from 1.2 to 1.6 and suggests that they are the products of a "living" polymerization. 1-Cyclobutenecarboxamide-derived ROMP polymers are excellent prospects for applications that require stereoregular chains functionalized with polar ligands.