• Journal of Microbiology
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• v.42 no.3
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• pp.211-215
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• 2004

Toxoplasmosis has been well known as an important human infection to consider especially in pregnant women. Although many serologic methods are available, the diagnosis of toxoplasmosis can be extremely difficult. The presence of increased levels of Toxoplasma-specific IgG antibodies indicates an infection, but it does not differentiate between a recent and past infection. The purpose of our study was to compare the performance of the ELISA T. gondii IgG/IgM test, a widely used enzyme-linked immunosorbent assay, to the ELISA IgG avidity method. One hundred and four serum samples (from 38 males and 66 females) were tested and evaluated from symptomatic patients (chorioretinitis, lymphadenopathy), and from women in their first trimester of pregnancy who were suspected of having toxoplasmosis, The high IgG avidity and ELISA IgG antibody levels were in agreement for 51 of the specimens (49.0％). Thirty-eight discrepant (borderline) results from the IgG avidity method were positive for IgM (3 specimens) and IgG (37 specimens). Interestingly, out of the eight serum samples that were positive for both IgG and IgM antibodies, two samples were low IgG avidity, and three samples were borderline. There was no statistically significant relation observed between the results of the IgG avidity method and the ELISA IgG test, and the IgG avidity method and ELISA IgM test (X$^2$=1.987; p=0.370 and X$^2$=2.152; p=0.341, respectively). The IgG avidity method was considered easy to perform and an acceptable approach for the differentiation of discrepant results (recent/chronic) and for the current detection of T. gondii antibodies. We concluded that the determination of IgG avidity is a helpful tool for the diagnosis of the ocular form of toxoplasmosis and it is a safe method for screening this disease in the first trimester of pregnancy.

• Korean Journal of Clinical Pharmacy
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• v.1 no.1
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• pp.31-36
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• 1991

Tobramycin is one of the most frequently selected agents for pharmacokinetic drug monitoring because of its narrow therapeutic index and essential role for the management of serious infections, especially gram-negative infections. Its pharmacokinetic parameters are dependent on race, sex, age, ideal body weight. disease states, and etc. Therefore, to schedule the dosing of tobramycin, the individual pharmacokinetic parameters such as half-life and volume of distribution are needed. However, these pharmacokinetic parameters have never been reported in Koreans. The purposes of this study were to evaluate the volume of distribution of tobramycin in cancer patients who had normal renal function, to compare the mean values of Vd reported in the literature, and to compare the measured half-life with the expected half-life based on ABW, LBW, and IBW, respectively. Venous blood samples were collected just before and thirty minutes after dosing during steady state. Serum tobramycin concentrations were determined by $TD_x$ (fluorescence immunoassay). IBW were measured by the method of Devine: and LBW were measured by the method of Hallynck. Creatinine clearances (CLcr) of the patients were estimated using the Cockcroft and Gault equation. Elimination rate constants (kel) were determined using the Welling and Craig equation. Infusion rate (ko), volume of distribution (Vd), and half-life $(t_{1/2})$ were determined using the Saw chuk and Zaske equation. The volume of distribution Was $27\%$ greater than the Schentag's study (0.26 vs 0.33 l/kg), but the half-life was similar to the Levy's study. The predicted half-lives based on IBW were the closest to actual half-lives (1.85 vs 2.01 hr).

• Biomedical Science Letters
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• v.16 no.3
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• pp.201-206
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• 2010

In order to develop procedures for the rapid isolation of recombinant sugar transporter in functional form from away from the endogenous insect cell transporter, gene fusion techniques were exploited. Briefly, BamH1-digested human HepG2 type glucose transport protein cDNA was first cloned into a transfer vector pBlueBacHis, containing a tract of six histidine residues. Recombinant baculoviruses including the human cDNA were then generated by allelic exchange following transfection of insect cells with wild-type BaculoGold virus DNA and the recombinant transfer vector. Plaque assay was then performed to obtain and purify recombinant viruses expressing the human transport protein. All the cell samples that had been infected with viruses from the several blue plaques exhibited a positive reaction in the immnuassay, demonstrating expression of the glucose transport protein. In contrast, no color development in the immunoassay was observed for cells infected with the wild-type virus or no virus. Immunoblot analysis showed that a major immunoreactive band of apparent Mr 43,000~44,000 was evident in the lysate from cells infected with the recombinant baculovirus. Following expression of the recombinant fusion protein with the metal-binding domain and enterokinase cleavage site, the fusion protein was recovered by competition with imidizole using immobilized metal charged resin. The leader peptide was then removed from the fusion protein by cleavage with porcine enterokinase. Final separation of the recombinant protein of the interest was achieved by passage over $Ni^{2+}$-charged resin under binding conditions. The expressed transport protein bound cytochalasin B and demonstrated a functional similarity to its human counterpart.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.900-903
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• 2012

Cadmium is known to be very toxic to human health and can be relative easily translocated from soils in plants. Therefore, a rapid method for screening Cd in soils and crops has become more and more important. For this reason, we examined a rapid immunochromatograpy (ICG) test kit which uses antigen-antibody reaction based on immunoassay and chromatography. Soils and rice grains collected from mine waste-contaminated sites were determined for their Cd contents using this kit. For comparison purposes, 0.1 M HCl and ICP-OES were employed as a conventional extraction and determination method. Cadmium contents in rice grains determined using ICG technique were $0.46{\sim}2.39mg\;kg^{-1}$ and Cd contents determined using 0.1 M HCl and ICP-OES were $0.52{\sim}1.97mg\;kg^{-1}$. The correlation between these two Cd contents were statistically significant ($r^2$=0.930). The results of Cd contents in soils also showed a statistically significant relationship between these two methods ($r^2$=0.975). On the basis of these results, ICG technique can be applied to rapidly quantify Cd in crops and soils. However, further research is necessary to apply ICG technique for the field screening.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.529-532
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• 2005

Expanding cells ex-vivo is very important in tissue-engineering. Culture medium is usually supplemented with fetal bovine serum(FBS) in most of the experiments. However, cells grown in bovine serum media may posses the possibilities of disseminating bovine diseases and/or stimulating the patient's immune reactions. To overcome these problems, autologous or homologous serum should be used instead of the FBS. The purpose of this study is to compare cell proliferation and collagen synthesis depending on the kind of sera mixed on media and to provide a guideline on applying established experimental data to clinical cases. Human dermal fibroblasts were obtained from four patients. Five thousand cells per well in 96-well plates were incubated DMEM/F-12 Nutrient with varying serum mixture; 10% autologous serum, 10% homologous serum, and 10% FBS. Five days after incubation fibroblast proliferation and collagen production were determined by MTT assay and CICP enzyme immunoassay. The mean cell number were; $3.95{\times}10^4/well$, $2.97{\times}10^4/well$ and $2.30{\times}10^4/well$, respectively. The average amounts of collagen synthesized were; 238.13 ng/ml, 204.88 ng/ml, and 163.88 ng/ml in each. These results show that the use of human serum mixture may contribute to, not only preventing disseminated infection of bovine diseases. but also increase cell proliferation and collagen synthesis without simulating the patient's immune reactions.

• Journal of Microbiology and Biotechnology
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• v.16 no.1
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• pp.136-140
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• 2006

In this study, we investigated the synergistic effects of Staphylococcus aureus extracts (membranes and walls) and lipopolysaccharide (LPS) derived from Escherichia coli on tumor necrosis factor (TNF) production in the pathogenesis of silica-induced inflammation. The synergistic induction of TNF by silica particles $(<20\;{\mu}m)$ in combination with either S. aureus extracts or LPS was examined in J774A.1 cell cultures. Media from the treated and untreated cell cultures were assayed for TNF, using the mouse WEHI 164 cell cytotoxicity assay and enzyme immunoassay. Cells exposed simultaneously to silica and $0.5\;{\mu}g/ml$ S. aureus extracts (or 0.5 ng/ml of LPS) produced a significantly higher level of TNF than those produced by the inducer alone. Our results indicate that device-associated infections (or pyrogen contamination) could enhance inflammatory responses, because of particles produced by the wear of medical implants or particulate biomaterials used for clinical purposes.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1267-1274
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• 2004

Colostrum contains various kinds of cytokines including TGF-$\beta$ that has potent regulatory effects on cells of the immune system. We compared the levels of TGF-$\beta$1 and TGF-$\beta$2 in bovine and human colostrum. Based on the isoform-specific ELISA, bovine colostrum collected on day 1 post-delivery retained $53.71{\pm}29.55\;ng/ml$ of TGF-$\beta$1 and $40.41{\pm}21.78\;{\mu}g/ml$ of TGF-$\beta$2 (n=4), while in human, $381.45{\pm}158.24\;ng/ml$ of TGF-$\beta$1 and $41.47{\pm}9.63\;ng/ml$ of TGF-$\beta$2 (n=5). Thus, dominant TGF-$\beta$ isoforms were completely opposite between human and bovine colostrum samples. The concentrations of both isoforms declined as lactation proceeded. Biological activities of the colostrum samples were determined using an MV1LU cell line. Consistent with the result from the immunoassay, TGF-$\beta$1 in human and TGF-$\beta$2 in bovine colostrum were responsible for the anti proliferative activity against MV1LU cells. Furthermore, bovine colostrum increased IgA secretion by LPS-stimulated mesenteric lymph node (MLN) cells, and this effect was abrogated by either anti­TGF-$\beta$2 antibody or combined anti-TGF-$\beta$1/$\beta$2 antibody, but not by anti- TGF-$\beta$1 antibody alone. Similarly, TGF-$\beta$2 in bovine colostrum enhanced the Ig germ line (GL) promoter activity, which is the earliest event toward IgA isotype switching. Taken together, these results suggest that TGF-$\beta$ isoforms, differentially expressed in human and bovine colostrum, may promote IgA isotype production in the neonatal intestine.

• The Korean Journal of Pain
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• v.14 no.1
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• pp.26-31
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• 2001

Background: Sympathetic blocks with local anesthetics are used to differentiate sympathetically- maintained pain (SMP) from sympathetically-independent pain (SIP). However, systemic lidocaine is also used in the management of neuropathic pain. Therefore, there may be possibility of a false positive response in relieving their pain by systemic absorption of lidocaine following a diagnostic sympathetic block in patients with SIP. In this study, we measured the plasma lidocaine concentrations after a stellate ganglion block (SGB) using three volumes of 1% lidocaine. Methods: This prospective, crossover study was performed in 3 patients who experience sudden hearing loss and in 4 volunteers. Each person received SGB three times using three different volumes (6 ml, 12 ml and 16 ml) of 1% lidocaine at one week intervals. SGB was performed using a 23 G butterfly needle via a paratracheal approach by two persons. Two ml of venous blood was obtained from a prepared contra-lateral sided venous route at 1, 3, 5, 7, 10, 20 and 60 min after SGB. Plasma lidocaine level was analyzed by immunoassay. Results: Mean plasma lidocaine concentrations correlated well with the volumes of 1% lidocaine used in SGB; larger volumes showed higher concentrations (P < 0.01). Mean peak plasma concentrations were $1.08{\pm}0.18$ in 6 ml, $1.90{\pm}0.47$ in the 12 ml and $2.74{\pm}0.67{\mu}g/ml$ in the 16 ml groups (P < 0.01). The mean time to reach peak plasma concentration was not significantly different between the three groups. Conclusions: The peak plasma lidocaine concentrations in SGB using large volume were found to be similar to that of IV lidocaine infusion in the management of neuropathic pain. These data suggest that diagnostic sympathetic block may result in many false positive responses for SMP. Part of its effect may be related to systemic local anesthetic absorption and not to a sympathetic block. Therefore, physicians may be required to use optimal volumes and minimal concentration of local anesthetic in diagnostic sympathetic block procedures and also make a careful assessment of the performance of a permanent sympathetic block.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.49-49
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• 2003

본 연구에서는 vesicular stomatitis virus G glycoprotein (VSV-G)를 envelope로 가지는 pantropic retrovirus vector system을 이용하여 재조합 human FSH 유전자가 전이된 형질전환 닭을 생산하고자 하였다. Human FSH $\alpha$ 및 $\beta$ 유전자와 CTP linker는 human pituitary gland cDNA library에서 RT-PCR 방법을 이용하여 cloning하였으며, 각각의 fragment는 FSH$\beta$-CTP-FSH$\alpha$ 순서의 단일사슬로 연결하였다. 연결된 FSH$\beta$-CTP-FSH$\alpha$는 retroviral vector 내의 $\beta$-actin promoter의 조절 하에 도입한 후, PT67 packaging cell line에 transfection하여 virus를 생산하였으며 생산된 virus는 pantropic한 virus producing cell인 GP293에 infection하여 FSH 유전자가 도입된 virus를 생산하였다. FSH 유전자의 발현을 in vitro에서 확인하기 위하여 CHO (chinese hamster ovary) 세포에 virus를 감염시킨 후, 세포의 배양액을 취하여 electrochemilumine-scence immunoassay 방법으로 정량하였다. In vitro에서 전이 후 발현이 확인된 FSH 외래유전자의 retroviral vector virus를 초원심분리로 고농축하여 stageX의 계란의 배반엽 층에 주입하였으며, 그 결과 18%의 부화율과 91%의 부화한 닭의 유전자 전이율을 확인할 수 있었다. 전이된 유전자의 확인은 FSH$\beta$와 Neo 유전자에 대한 primer를 이용한 RT-PCR의 방법을 이용하였다. In vitro에서와는 달리 in vivo에서는 FSH 유전자의 전이는 확인되었으나 발현을 확인하지는 못하였는데, 이는 적은 수의 실험군이 형질전환율에 비해 상대적이지 못하였거나, 외래 유전자인 FSH의 발현에 의한 생리적인 부작용이 유발되어 해당개체가 부화되지 못한 것으로 추정된다. 본 문제점을 해결하기 위하여 실험군의 수를 늘리고 외래 유전자에 대한 controllable expression system이 보완될 필요성이 요구되며, 이러한 점이 해결된다면 높은 유전자 전이율에 기인하여 retrovirus를 이용한 형질전환 방법은 형질전환 가금의 생산에 있어서 매우 효율적이고 주목할 만한 방법으로 사료된다.

• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.371-378
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• 1998

Pesticide has played important role in Korean and Austrailian agriculture. In addition, pesticides are the most reliable tools pests in agriculture. Recently, it is highly recommended that the use of pesticide should be concerned with both atricultural and environmental aspect, also legislation on environmental contamination has been fortified to the world. Particularly, the attention on agrochemicals has been focused on the soil abuse and the water contamination at present time. In spite of this kind of concern, a few research about pesticides using in Australia and Korean have been conducted to their behaviors under australian and korean environment to avoid environmental contamination by pesticides. Thus, the research organizations need facilities to analyze the characteristics of each pesticide and the environmental fate of pesticides. The conventional analytical method to detect pesticides and their metabolites can not be overcome to reduce time, expenditure, and complexity of analysis even though the methods are accurate and precise. For example, High performance liquid chromatography(HPLC), and gas chromatography (GC) used until now are less choice detectors and often lower sensitive. In contrast to the conventional analytical methods, biosensors are so fast in analysis and has high productivity and analyze multi=sample simultaneously. Therefore, it is biosensing analytical method that we could consider as an alternative method intead of the conventional methods.