• Journal of Pharmaceutical Investigation
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• v.41 no.5
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• pp.263-272
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• 2011

Tablet dosage forms have been preferred over other formulations for the oral drug administration due to their low manufacturing costs and ease of administrations, especially controlled-release applications. Controlled-release tablets are oral dosage forms from which the active pharmaceutical ingredient (API) is released over an intended or extended period of time upon ingestion. This may allow a decrease in the dosing frequency and a reduction in peak plasma concentrations and hence improves patient compliance while reducing the risk of undesirable side effects. Conventional singlelayered matrix tablets have been extensively utilized to deliver APIs into the body. However, these conventional single-layered matrix tablets present suboptimal delivery properties, such as non-linear drug delivery profiles which may cause higher side effects. Recently, a multi-layered technology has been developed to overcome or eliminate the limitations of the singlelayered tablet with more flexibility. This technology can give a good opportunity in formulating new products and help pharmaceutical companies enhancing their life cycle management. In this review, a brief overview on the multi-layered tablets is given focusing on the various tablet designs, manufacturing issues and drug release profiles.

• Journal of Pharmaceutical Investigation
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• v.39 no.2
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• pp.111-115
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• 2009

The pharmacokinetics of cyclosporin A (CsA) after single and multiple oral dosing of new CsA self-micro-emulsifying drug delivery system (SMEDDS) in dogs were estimated. A single dose study was performed following a two-way crossover design against six dogs with reference SMEDDS. For a multiple dose study, three dogs were allocated for each drug, and 100 mg of drug was administered daily for 6 days. Whole blood concentration of CsA was analyzed by radio-immunoassay. Both drug showed identical blood concentration profiles in both studies, and no statistical difference was detected in pharmacokinetic parameters. The relative bioavailabilities of test SMEDDS were 91.4% and 89.1%, respectively, in the single dose study and the last day of multiple dose study. Especially, multiple dose study proved the good relationship between C-0/C-2 and AUC for reference SMEDDS, which is an indispensable part of therapeutic drug monitoring. These results suggest newly formulated CsA SMEDDS possibly shows identical pharmacokinetics and pharmacodynamic behaviors in clinical trials.

• Environmental Engineering Research
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• v.20 no.4
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• pp.397-402
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• 2015

SCR has been popularly approved as one of the most effective means for NOx emission control in heavy-duty and medium-duty vehicles currently. However, high urea dosing would lead to ammonia slip. And $NH_3$ sensor for vehicle emission applications has not been popularly used in real applications. This paper presents experimental studies on the diesel engine urea-SCR system by using a double NOx sensor system that is arranged in the downstream of the SCR catalyst based on ammonia cross-sensitivity. It was shown that the NOx conversion efficiency rised as $NH_3/NOx$ increases and the ammonia slip started from the $NH_3/NOx$ equal to 1.4. The increase of temperature caused high improvement of the SCR reaction rate while the space velocity had no obvious change. The ammonia slip was in advance as catalyst temperature or space velocity increase and the ammonia storage reduced as catalyst temperature or space velocity increase. The NOx real-time conversion efficiency rised as the ammonia accumulative storage increase and reached the maximum value gradually.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.4
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• pp.241-244
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• 2011

A lectin from the hemolymph of purse crab, Philyra pisum, was found to have anti-proliferative activity on human lung cancer cells by our laboratory. In this study, P. pisum lectin (PPL) was molecularly characterized including molecular mass, amino acid sequences, amino acid composition, and the effects of metal ions, temperature, and pH on the activity. We found that PPL showed mitogenic activity on human lymphocytes and BALB/c mouse splenocytes. The mitogenic activity (maximum stimulation index, $SI=9.57{\pm}0.59$) of PPL on human lymphocytes was higher than that of a standard well-known plant mitogen, concanavalin A (maximum $SI=8.80{\pm}0.59$). The mitogenic activity mediated by PPL is required for optimum dosing, and higher or lower concentrations caused decreases in mitogenic response. PPL also induced mitogenic activity on mouse splenocytes, however, the maximum SI ($1.77{\pm}0.09$) on mouse splenocytes of PPL was lower than that ($2.14{\pm}0.15$) of concanavalin A. In conclusion, PPL is a metal ion-dependent monomer lectin with mitogenic activity, and could be used as a lymphocyte or splenocyte stimulator.

• Journal of Adhesion and Interface
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• v.7 no.4
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• pp.28-31
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• 2006

Due to the miniaturization of MEMS and microelectronics the joining techniques also have to be adjusted. The dosing technology with viscous adhesives does not permit reproducible adhesive volumes, which are clearly under a nano-liter. A nano-liter means however a diameter of bonding area within the range of several 100 micrometers. Additional, viscous adhesives need a certain time, until they are cross linked or cured. The problem especially in the MEMS is the initial strength, since it gives the time, which is needed for joining an individual adhesive joint. The time up to the initial strength is with viscous, also with fast curing systems, within the range of seconds until minutes. Until the reach of the initial strength, the micro part must be fixed/held. Without sufficient adjustment/clamping it can come to a shift of the micro parts. Also existing micro adhesive bonding processes are not batch able, i.e. the individual adhesive joints of a micro system must be processed successively. In the context of the WCARP III 2006 now an innovative method is to be presented, how it is possible to solve the existing problems with micro bonding. i.e. a method is presented, which is batch able, possess a minimum joining geometry with some micrometers and is so fast that no problems with the initial strength arise. It is a method, which could revolutionize the sticking technology in the micro system engineering.

• Journal of Magnetics
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• v.11 no.4
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• pp.182-188
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• 2006

The search for high-density recording materials has been one of most active and vigorous field in the field of magnetism. $FePt-L1_{0}$ nanoparticle has emerged as a potential candidate because of its high anisotropy. In this paper, we provide an overview of recent work at Argonne National Laboratory that contributes to the ongoing dialogue concerning the relation between structure and properties of the FePt nanoparticle system. In particular we discuss the ability to control structure and properties via dosing with Cr. Cr-dosed FePt films were grown via molecular beam epitaxy and annealed at $550^{\circ}C$ in an ultrahigh vacuum chamber, and were studied with the surface magneto-optic Kerr effect (SMOKE), scanning electron microscopy (SEM) and x-ray magnetic circular dichroism (XMCD). We found that small dosage of Cr helps to generate $L1_{0}$ phase FePt magnetic nanoparticles with small size, defined shape and regular spatial distribution on MgO (001) substrate. The nanostructures are ferromagnetic with high magnetic coercivity (${\sim}0.9T$) and magnetic easy axis in the desired out-of-plane orientation. We also show that controlling the lateral region where nanostructures exist is possible via artificial patterning with Cr.

• Advances in Traditional Medicine
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• v.7 no.2
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• pp.205-210
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• 2007

The objectives of the study were (1) To evaluate the safety and tolerability of Damtab. (2) To characterize hypoglycemic effect of Damtab, if any. (3) To evaluate insulin sensitivity effect of Damtab, if any. Hypoglycemic effect of Damtab (700 mg and 1,400 mg) were examined. Gliclazide (80 mg) was used as an active control. Placebo was used as control. Breakfast was given, half an hour before dosing whereas lunch, snacks and dinner were given at 6, 10 and 14 h post dose. An oral glucose tolerance test was conducted to calculate the insulin sensitivity index from the values of glucose and insulin during oral glucose tolerance test. Both giclazide 80 mg and Damtab 1,400 mg significantly lowered plasma glucose level up to 6 h. Insulin sensitivity index of Damtab (1,400 mg) was found to be similar to that of placebo. A significant increase in insulin level at 1 h post dose of Damtab (1,400 mg) was observed. Damtab 700 mg shows placebo like effect whereas Damtab 1,400 mg possesses hypoglycemic effect.

• Korean Journal of Clinical Pharmacy
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• v.30 no.2
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• pp.87-91
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• 2020

Background: Levothyroxine is an essential drug for the treatment of hypothyroidism or related diseases. Several studies have reported an association between the effects of levothyroxine treatment and time of administration, which can be inconsistent. Objective: This study was conducted to compare the levels of thyroid-stimulating hormone or free thyroxine between morning and nighttime dosing of levothyroxine. Methods: We reviewed previously reported relevant articles and conducted a meta-analysis. Results: In total, five studies were included in this meta-analysis. Results showed that thyroid-stimulating hormone (standard difference in means [SE]=0.321; 95% confidence interval [CI], -0.016 to 0.657) and free thyroxine (SE= -1.367; 95% CI, -2.943 to 0.210) levels did not differ significantly between morning (before breakfast) and nighttime (before bedtime) administration. Conclusion: This is the first meta-analysis to evaluate the effects of time of administration on levothyroxine levels in patients with hypothyroidism. Based on our results, we suggest considering patients' lifestyles or daily routines when counselling them on the optimal time of administration for levothyroxine.

• The Journal of Korean Medicine
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• v.29 no.3
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• pp.21-37
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• 2008

Objectives: The purpose of this study was to verify the effect of Palmiboshinwhan (PMBSW) in methotrexate (MTX)-induced immunosuppressed SD rats. Methods: The test articles were once a day dosed for 14 days by gastric gavage from 2 days after last MTX-dosing, and changes in body weight, spleen weight and total blood leukocyte numbers were observed with total lymphocyte numbers, B and T lymphocyte percentages, CD3+CD4+, CD3+/CD8+, CD4+/CD8+ T lymphocyte percentages in the blood and spleen, the serum interleukin (IL)-2 levels and the productivity of IL-2 of splenic cells. Result & Conclusion: It is concluded that PMBSW has relatively good immunostimulating effect in the MTX-induced immunosuppressed SD rats. Theefficient dosage was considered above 500mg/kg. In addition, it is considered that the immunostimulating effect of PMBSW was mediated to both the B and T lymphocytes. The more favorable effects were detected in T lymphocytes rather than B lymphocytes, and PMBSW showedrelatively good stimulating potential against CD4+ T lymphocytes but not any stimulating effect against CD8+ T lymphocytes in the present study.

• Journal of Society of Preventive Korean Medicine
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• v.15 no.2
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• pp.21-38
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• 2011

Objective : This study was to evaluate the single dose toxicity of Bojungikki-tang(Buzhongyiqi-tang, BJIKT) in male and female mice. Method : Aqueous extracts of BJIKT were administered to female and male ICR mice as an oral dose of 2,000, 1,000 and 500 mg/kg (body weight) according to the recommendation of Korea Food and Drug Administration (KFDA) Guidelines. Animals were monitored for the mortality and changes in body weight, clinical signs and gross observation during 14 days after dosing, upon necropsy ; organ weight and histopathology of 12 principle organs were examined. Results : we could not find any mortality, clinical signs, and changes in the body and organ weight. In addition, no BJIKT-treatment related abnormal gross findings and changes in histopathology of principle organs were detected except for some sporadic accidental findings. Conclusion : The results obtained in this study suggest that the 50% lethal dose and approximate lethal dose of BJIKT aqueous extracts in both female and male mice were considered as over 2,000 mg/kg, the limited highest dosage recommended by KFDA Guidelines, and can be safety used in clinics.