• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2335-2340
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• 2014

Paclitaxel is hydrophobic in nature and is recognized as a highly toxic anticancer drug, showing adverse effects in normal body sites. In this study, we developed a polymeric nano drug carrier for safe delivery of the paclitaxel to the cancer that releases the drug in a sustained manner and reduces side effects. N-isopropylacrylamide/vinyl pyrrolidone (NIPAAm/VP) nanoparticles were synthesized by radical polymerization. Physicochemical characterization of the polymeric nanoparticles was conducted using dynamic light scattering, transmission electron microscopy, scanning electron microscopy and nuclear magnetic resonance, which confirmedpolymerization of formulated nanoparticles. Drug release was assessed using a spectrophotometer and cell viability assays were carried out on the MCF-7 breast cancer and B16F0 skin cancer cell lines. NIPAAm/VP nanoparticles demonstrated a size distribution in the 65-108 nm range and surface charge measured -15.4 mV. SEM showed the nanoparticles to be spherical in shape with a slow drug release of ~70% in PBS at $38^{\circ}C$ over 96 h. Drug loaded nanoparticles were associated with increased viability of MCF-7 and B16F0 cells in comparison to free paclitaxel. Nano loaded paclitaxel shows high therapeutic efficiency by sustained release action for the longer period of time, i increasing its efficacy and biocompatibility for human cancer therapy. Therefore, paclitaxel loaded (NIPAAm/VP) nanoparticles may provide opportunities to expand delivery of the drug for clinical selection.

• Biomaterials and Biomechanics in Bioengineering
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• v.2 no.3
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• pp.159-172
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• 2015

Treatment of polymicrobial infected musculoskeletal defects continues to be a challenge in orthopaedics. This research investigated single and dual-delivery of two antibiotics, vancomycin and amikacin, targeting different classes of microorganism from a biodegradable calcium sulfate-chitosan-nHA microsphere composite scaffold. The addition of chitosan-nHA was included to provide additional structure for cellular attachment and as a secondary drug-loading device. All scaffolds exhibited an initial burst of antibiotics, but groups containing chitosan reduced the burst for amikacin at 1hr by 50%, and vancomycin by 14-25% over the first 2 days. Extended elution was present in groups containing chitosan; amikacin was above MIC ($2-4{\mu}g/mL$, Pseudomonas aeruginosa) for 7-42 days and vancomycin was above MIC ($0.5-1{\mu}g/mL$ Staphylococcus aureus) for 42 days. The antibiotic activity of the eluates was tested against S. aureus and P. aeruginosa. The elution from the dual-loaded scaffold was most effective against S. aureus (bacteriostatic 34 days and bactericidal 27 days), compared to vancomycin-loaded scaffolds (bacteriostatic and bactericidal 14 days). The dual- and amikacin-loaded scaffolds were effective against P. aeruginosa, but eluates exhibited very short antibacterial properties; only 24 hours bacteriostatic and 1-5 hours bactericidal activity. For all groups, vancomycin recovery was near 100% whereas the amikacin recovery was 41%. In conclusion, in the presence of chitosan-nHA microspheres, the dual-antibiotic loaded scaffold was able to sustain an extended vancomycin elution longer than individually loaded scaffolds. The composite scaffold shows promise as a dual-drug delivery system for infected orthopaedic wounds and overcomes some deficits of other dual-delivery systems by extending the antibiotic release.

• Korean Journal of Health Education and Promotion
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• v.3 no.1
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• pp.63-73
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• 1985

Ratio of physically and mentally handicapped people among the total population is about 3∼4%. Regardless of the extent of seriousness of handicaps, they have to sustain various difficulties in their life time and pose challenging problems to their homes, community and nation. In the spectrum of their problems, measures such as treatment, rehabilitation and welfare work all occupied important part but most significant measure is the prevention. Such handicaps items from health care of maternal and child, mostly causes throughout the process of pregnancy, delivery and upbringing. And then this study is focused on the pregnant history of the mothers with handicapped children. The objective of this study is to identify the basic factors which can create a handicapped child during pregnancy and is to prevent the birth of such a child. For this study, 301 mothers who have handicapped children were selected, now receiving various training at 5 rehabilitation and educational facilities. And questionnaires distributed to them during the period of Oct, 1983 to Dec, 14. The collected responses have been analized in terms of significant numbers, percentage and metic average. Their related results are as follows: 1. The sexual ratio between the male and female was 58.5% compare 41.5%. The average age of the handicapped children was 10.1 years old and that of mothers at the time of the children's birth was 28.9 old years. They were born as 2.14th in their family, the ratio of antenatal care for pregnant mothers was 36.2% and 22.9% were abnormally delivered. 37.9% out of the total were born from mothers with ages above 35 years and as their first baby. 2. The time of confirming the handicapped nature of children was during babyhood by 97.1% and discovery of these misfortunes were made by chance. As for causes of those-handicapped status 20.9% disease from complication, 15.3% from difficulties experience at the time of delivery, 11.3% from heredity and 10% were results of drug abuse during pregnancy, and 49.8% of the handicapped children were mentally retarded.

• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.131-137
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• 1994

Drug delivery system by the use of red blood cells was established to sustain the release of drugs in the circulatory system by the intravenous injection. The entrapment method by the preswelling technique was re-examined and evaluated for searching the new entrapping conditions without hemolysis. The addition of 4 volume of $0.6{\times}\;hank's$ balanced salt solution (HBSS) into 1 volume of 50% red blood cells suspension did not induce the hemolysis and change the hematocrit level in this experimental condition (within 15 min). Most of daunorubicin could be entrapped into red blood cells within 15 min. While the intracellular adenosine triphosphate (ATP) level followed by the entrapment was reduced to 86% of normal ATP level, the membrane fluidity and the shape factor of red blood cells were not altered. The release rate of daunorubicin from red blood cells was affected by the hemolysis under this condition. To maintain the intracellular ATP in red blood cells, the new reaction buffer was made With the addition of ATP and sodium pyruvate during the entrapment procedure because the hemolysis during the release test would reflect the loss of intracellular ATP that might result in the decrease of the viability in vivo. The addition of ATP raised the intracellular ATP level, which protect the hemolysis during the release test.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.1
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• pp.3-11
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• 2003

Attention-deficit/Hyperactivity disorder(ADHD) is the most common psychiatric disorder of childhood and among the most prevalent chronic health conditions affecting school-aged children. Children with ADHD experience significant functional problems, such as school difficulties, academic underachievement, troublesome interpersonal relationships with family members and peers, and low self-esteem. The most widely used pharmacological treatments for ADHD are psychostimulants, such as methylphenidate and amphetamine salts. These medications provide clinical efficacy by increasing the availability of catecholamines, primarily dopamine, in the frontal lobe of the brain. immediate-release(IR) formulations of sychostimulants were among the most effective psychotrophic medications in the psychopharmacological treatment. However, there are some limitations of IR formulations：the short half-life and duration of efficacy, which result in the need for multiple daily dosing and the poor compliance. These limitations have led to the development of once-daily, extended-release(ER) formulations of methylphenidate and amphetamine salts. However, these ER formulations may not be as immediately helpful to ADHD children due to delayed onset of action and the acute tolerance which is the failure to sustain the efficacy with the same concentration of drug as the initial stage of medication. OROS-methylphenidate(Concerta$^{\circledR}$) given once a day produces an ascending-pattern plasma drug level generated by the osmotically released, timed drug-delivery system. These new formulations of the psychostimulants have been shown to be a useful alternative to old stimulant medications through the evidence by the clinical trials.