• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.3851-3866
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• 2015

The dynamic nature of opportunistic networks results in long delays, low rates of success for deliveries, etc. As such user experience is limited, and the further development of opportunistic networks is constrained. This paper proposes a prediction-based routing method for opportunistic networks (PB-OppNet). Firstly, using an ARIMA model, PB-OppNet describes the historical contact information between a node pair as a time series to predict the average encounter time interval of the node pair. Secondly, using an optimal stopping rule, PB-OppNet obtains a threshold for encounter time intervals as forwarding utility. Based on this threshold, a node can easily make decisions of stopping observing, or delivering messages when potential forwarding nodes enter its communication range. It can also report different encounter time intervals to the destination node. With the threshold, PB-OppNet can achieve a better compromise of forwarding utility and waiting delay, so that delivery delay is minimized. The simulation experiment result presented here shows that PB-OppNet is better than existing methods in prediction accuracy for links, delivery delays, delivery success rates, etc.

• Archives of Pharmacal Research
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• v.29 no.7
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• pp.598-604
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• 2006

In many conventional drug delivery systems in vogue, failure to deliver efficient drug delivery at the target site/organs; is evident as a result, less efficacious pharmacological response is elicited. Microspheres can be derived a remedial measure which can improve site-specific drug delivery to a considerable extent. As an application, Lung-targeting Ofloxacin-loaded gelatin microspheres (GLOME) were prepared by water in oil emulsion method. The Central Composite Design (CCD) was used to optimize the process of preparation, the appearance and size distribution were examined by scanning electron microscopy, the aspects such as in vitro release characteristics, stability, drug loading, loading efficiency, pharmacokinetics and tissue distribution in albino mice were studied. The experimental results showed that the microspheres in the range of $0.32-22\;{\mu}m$. The drug loading and loading efficiency were 61.05 and 91.55% respectively. The in vitro release profile of the microspheres matched the korsmeyer’s peppas release pattern, and release at 1h was 42%, while for the original drug, ofloxacin under the same conditions 90.02% released in the first half an hour. After i.v. administration (15 min), the drug concentration of microspheres group in lung in albino mice was $1048\;{\mu}g/g$, while that of controlled group was $6.77\;{\mu}g/g$. GLOME found to release the drug to a maximum extent in the target tissue, lungs.

• Journal of Society of Preventive Korean Medicine
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• v.25 no.3
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• pp.1-14
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• 2021

Objectives : This study aimed to investigate the perception level of Telemedicine among Korean medical doctors. Methods : The on-line survey was administered for Korean Medicine doctors. The survey consisted of 46 questions, addressing issues on concepts and adoption model of Telemedicine. Data were collected from 528 Korean medical doctors, and were analyzed using frequency analysis, t-test, ANOVA, and Kruskalwallis test. Results : The results showed that more than half of respondents had positive attitude towards implementation of Telemedicine in Korean Medicine and conventional medicine areas. Respondents were most positive about the aspect that Telemedicine could reduce 'hospital use by people with disabilities', while they were most concerned about the possibility that patients could be concentrated in large-scale hospitals. As prerequisites for the introduction of Telemedicine, accurate information delivery during remote communication between doctors and patients, clarification of responsibility for Telemedicine at the policy level, and development of equipment for accurate information delivery at the technical level received high responses. Conclusions : Korean Medicine doctors were positive about the implementation of Telemedicine, and they preferred to remote monitoring between doctors and patients. The development of medical equipment for accurate patient information delivery and the establishment of an institutional basis for clarifying responsibilities in case of medical accidents are required.

• Journal of Pharmaceutical Investigation
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• v.35 no.6
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• pp.403-409
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• 2005

For transdermal delivery of large molecular drugs such as vaccine and protein drugs, novel microneedle treatment device with roll was designed. The roll dimension is 1.43 cm diameter and 2.8 cm perimeter. Total number of microneedle on the roll is 3,360 with $230\;{\mu}m$ height and $740\;{\mu}m$ distance. The pore with $150\;{\mu}m$ depth and $35\;{\mu}m$ diameter on the skin was made by the designed microneedle device. This system could be achieved without pain. The permeation rates of FITC labelled ovalbumin (FITC-OVA, molecular weight: 45,000 g/mol) as a model protein were determined by modified Franz diffusion cells using skins of hairless mice or SD rats which were treated by using microneedle device two or four times. The average penetration fluxes of model protein increased from 674 to $872\;{\mu}g/cm^{2}{\cdot}hr$ as the number of treatment to make pore increased from two to four times. In conclusion, we confirmed the possibility of using the designed microneedle treatment device for transdermal delivery of the large molecular drugs.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.1067-1072
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• 2013

Hiwi, a human homologue of the Piwi family, plays an important role in stem cell self-renewal and is overexpressed in various human tumors. This study aimed to determine whether an RNA interference-based strategy to suppress Hiwi expression could inhibit tumor growth in a xenograft mouse model. A rare population of $SSC^{lo}\;Alde^{br}$ cells was isolated and identified as lung cancer stem cells in our previous study. Plasmids containing U6 promoter-driven shRNAs against Hiwi or control plasmids were successfully established. The xenograft tumor model was generated by subcutaneously inoculating with lung cancer stem cell $SSC^{lo}\;Alde^{br}$ cells. After the tumor size reached about 8 mm in diameter, shRNA plasmids were injected into the mice via the tail vein three times a week for two weeks, then xenograft tumor growth was assessed. In nude mice, intravenously delivery of Hiwi shRNA plasmids significantly inhibited tumor growth compared to treatment with control scrambled shRNA plasmids or the vehicle PBS. No mice died during the experiment and no adverse events were observed in mice administered the plasmids. Moreover, delivery of Hiwi shRNA plasmids resulted in a significant suppressed expression of Hiwi and ALDH-1 in xenograft tumor samples, based on immunohistochemical analysis. Thus, shRNA-mediated Hiwi gene silencing in lung cancer stem cells by an effective in vivo gene delivery strategy appeared to be an effective therapeutic approach for lung cancer, and may provide some useful clues for RNAi gene therapy in solid cancers.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.1
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• pp.29-36
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• 2006

The purpose of this study was to measure the pizza purchasing behavioral characteristics of respondents and importances of factors affecting pizza purchase, to estimate the effects of attributes on pizza restaurant choice, and to predict probability of selecting a particular pizza restaurant The questionnaire consisted of two parts: The paired experimental profiles, purchasing behavior and importances of factors affecting pizza purchase. This study generated profiles of 16 hypothetical pizza restaurant based on the seven attributes. The profiles comprised 16 discrete sets of variables, each of which had two levels. For this study, researcher randomly selected 150 students of university as respondents. Twenty students did not complete the survey instrument, resulting in a final sample size of 129. All estimations were carried out using frequency, correlation, phreg procedure of SAS package. The results were as followed Based on the estimated model, the -2LL(B) statistic for a model with all explanatory variables was 5585.761 and the Chi-square statistic is 134.786 with 7 df (p<0.001). At p<0.001, we would reject the null hypothesis that the attributes do not influence choice. The parameter estimate for price was highest, followed by late delivery time, promised delivery time, money-back guarantee, discount, pizza variety, and pizza temperature. The result from this study suggested that there was an opportunity to increase market share and profit by improving operations so that customers receive discount and money-back guarantee simultaneously, and by reducing price, delivery time.

• Journal of Ginseng Research
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• v.42 no.4
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• pp.512-523
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• 2018

Background: 20(S)-Protopanaxadiol (20S-PPD) is a fully deglycosylated ginsenoside metabolite and has potent dermal antiaging activity. However, because of its low aqueous solubility and large molecular size, a suitable formulation strategy is required to improve its solubility and skin permeability, thereby enhancing its skin deposition. Thus, we optimized microemulsion (ME)-based hydrogel (MEH) formulations for the topical delivery of 20S-PPD. Methods: MEs and MEHs were formulated and evaluated for their particle size distribution, morphology, drug loading capacity, and stability. Then, the deposition profiles of the selected 20S-PPD-loaded MEH formulation were studied using a hairless mouse skin model and Strat-M membrane as an artificial skin model. Results: A Carbopol-based MEH system of 20S-PPD was successfully prepared with a mean droplet size of 110 nm and narrow size distribution. The formulation was stable for 56 d, and its viscosity was high enough for its topical application. It significantly enhanced the in vitro and in vivo skin deposition of 20S-PPD with no influence on its systemic absorption in hairless mice. Notably, it was found that the Strat-M membrane provided skin deposition data well correlated to those obtained from the in vitro and in vivo mouse skin studies on 20S-PPD (correlation coefficient $r^2=0.929-0.947$). Conclusion: The MEH formulation developed in this study could serve as an effective topical delivery system for poorly soluble ginsenosides and their deglycosylated metabolites, including 20S-PPD.

• Molecules and Cells
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• v.42 no.11
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• pp.755-762
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• 2019

Despite decades of research into colorectal cancer (CRC), there is an ongoing need for treatments that are more effective and safer than those currently available. Lactic acid bacteria (LAB) show beneficial effects in the context of several diseases, including CRC, and are generally regarded as safe. Here, we isolated a Lactobacillus rhamnosus (LR)-derived therapeutic protein, p8, which suppressed CRC proliferation. We found that p8 translocated specifically to the cytosol of DLD-1 cells. Moreover, p8 down-regulated expression of Cyclin B1 and Cdk1, both of which are required for cell cycle progression. We confirmed that p8 exerted strong anti-proliferative activity in a mouse CRC xenograft model. Intraperitoneal injection of recombinant p8 (r-p8) led to a significant reduction (up to 59%) in tumor mass when compared with controls. In recent years, bacterial drug delivery systems (DDSs) have proven to be effective therapeutic agents for acute colitis. Therefore, we aimed to use such systems, particularly LAB, to generate the valuable therapeutic proteins to treat CRC. To this end, we developed a gene expression cassette capable of inducing secretion of large amounts of p8 protein from Pediococcus pentosaceus SL4 (PP). We then confirmed that this protein (PP-p8) exerted anti-proliferative activity in a mouse CRC xenograft model. Oral administration of PP-p8 DDS led to a marked reduction in tumor mass (up to 64%) compared with controls. The PP-p8 DDS using LAB described herein has advantages over other therapeutics; these advantages include improved safety (the protein is a probiotic), cost-free purification, and specific targeting of CRC cells.

• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.493-502
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• 2021

We prepared and investigated a biosynthesized nanoparticulate system with high adsorption and release capacity of letrozole. Silver nanoparticles (AgNPs) were biosynthesized using olive leaf extract. Cysteine was capped AgNPs to increase the adsorption capacity and suitable interaction between nanoparticles and drug. Morphology and size of nanoparticles were confirmed using transmission electron microscopy (TEM). Nanoparticles were spherical with an average diameter of less than 100 nm. Cysteine capping was successfully confirmed by Fourier transform infrared resonance (FTIR) spectroscopy and elemental analysis (CHN). Also, the factors of letrozole adsorption were optimized and the linear and non-linear forms of isotherms and kinetics were studied. Confirmation of the adsorption data of letrozole by cysteine capped nanoparticles in the Langmuir isotherm model indicated the homogeneous binding site of modified nanoparticles surface. Furthermore, the adsorption rate was kinetically adjusted to the pseudo-second-order model, and a high adsorption rate was observed, indicating that cysteine coated nanoparticles are a promising adsorbent for letrozole delivery. Finally, the kinetic release profile of letrozole loaded modified nanoparticles in simulated gastric and intestinal buffers was studied. Nearly 40% of letrozole was released in simulated gastric fluid with pH 1.2, in 30 min and the rest of it (60%) was released in simulated intestinal fluid with pH 7.4 in 10 h. These results indicate the efficiency of the cysteine capped AgNPs for adsorption and release of drug letrozole for breast cancer therapy.

• Journal of Korean Society of Rural Planning
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• v.25 no.1
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• pp.51-65
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• 2019

This study developed diagnostic system to understand the level of welfare cultural service and infrastructure in rural areas. The applicability was reviewed through the Delphi survey and the sample survey of 60 villages. The diagnostic indicators consist of three areas: the demand area, supply area, and delivery area. The demand area consists of 8 indicators, 25 indicators for welfare services and infrastructure (healthcare, social welfare) and 32 indicators for cultural services and infrastructure (culture, education, leisure sports). The service delivery area was divided into service supply area access and traffic accessibility (public transport use status and rural transport model status) by each indicator. A diagnostic system was applied to 60 villages. Services and infrastructure for rural welfare and culture were supplied more in the Si area than Gun area. The delivery area was easier to access the Gun area than Si area. In the case of traffic access, public transportation was more frequently used in the Si area than Gun area, and the rural transportation model was found to have a relatively large amount in the Gun area compared to Si area. The diagnosis system about services and infrastructure for rural welfare and culture will provide information necessary for establishment and decision making of regional development policy taking into account characteristics of rural areas in the future.