• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.575-580
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• 2014

The liquid crystalline copolymers were synthesized through direct polycondensation using 4-[4-(4-hydroxyphenoxy)butoxy]benzoic acid (HBBA) and p-hydroxy benzoic acid (HBA) as monomers. The structure and properties for synthesized copolymers were investigated by $^1H$-NMR, FT-IR, differential scanning calorimetry (DSC), thermogravimetry analysis (TGA) and polarizing optical microscope (POM). As result of investigations, inherent viscosities (${\eta}_{inh}$) of polymers were measured as 0.77~1.60 dL/g in phenol/p-chlorophenol/1,1,2,2-tetrachloroethane (25/40/35=w/w/w). Except for P-80, the ranges of the transition and mesophase temperature of copolymers were increased with increasing the amount of HBA. These properties of polymers were presumably due to increasing of the irregularity and rigidity of polymer chains.

• CELLMED
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• v.4 no.1
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• pp.6.1-6.12
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• 2014

Anthrax is the deadly disease for human being caused by Bacillus anthracis. Instantaneous research work on the mode of infection of the organism revealed that different proteases are involved in different steps of pathogenesis. Present study reports the in silico characterization and the detection of pathogenic proteases involved in anthrax infection through protein-protein interaction. A total of 13 acid, 9 neutral, and 1 alkaline protease of Bacillus anthracis were selected for analysing the physicochemical parameter, the protein superfamily and family search, multiple sequence alignment, phylogenetic tree construction, protein-protein interactions and motif finding. Among the 13 acid proteases, 10 were found as extracellular enzymes that interact with immune inhibitor A (InhA) and help the organism to cross the blood brain barrier during the process of infection. Multiple sequence alignment of above acid proteases revealed the position 368, 489, and 498-contained 100% conserved amino acids which could be used to deactivate the protease. Among the groups analyzed, only acid protease were found to interact with InhA, which indicated that metalloproteases of acid protease group have the capability to develop pathogenesis during B. anthracis infection. Deactivation of conserved amino acid position of germination protease can stop the sporulation and germination of B anthracis cell. The detailed interaction study of neutral and alkaline proteases could also be helpful to design the interaction network for the better understanding of anthrax disease.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.4041-4046
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• 2010

Wholly aromatic polyesters having flexible alkoxy side chain were synthesized by direct polycondensation. The synthetic polymers have been characterized by $^1H$-NMR, FT-IR. DSC, TGA, optical polarizing microscope and X-ray diffractometer. The inherent viscosities (${\eta}_{inh}$) measured in 1,1,2,2-tetrachloroethane (TCE) were 0.46~2.41 dL/g. The polymers having side chain showed double melting transition, ie, solid-sanidic liquid crystalline (LC) phase transition ($T_{m1}$) and sanidic LC phase-nematic LC phase transition ($T_{m2}$). As incresing length of alkoxy side chain, phase transition temperatures decreased and solubilities in organic solvents incresed. The peaks of $2{\theta}\;{\simeq}5$ and $2{\theta}\;{\simeq}20$ in X-ray diffractograms are due to crystallization of polymer main chain and of long side chain, respectively.

• Biomedical Science Letters
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• v.19 no.4
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• pp.330-337
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• 2013

There are several methods currently being used to diagnose tuberculosis in patients, such as smear, PCR, tuberculosis culture and X-ray. For a proper medical treatment, antimicrobial susceptibility test and rapid drug susceptibility testing have been operated. Tuberculosis bacilli usually need 3~8 weeks of culture period because of delay in RNA synthesis and require 15~22 hours for generation. After a germ raises in culture, we initiated antimicrobial susceptibility test for a proper treatment. It has some difficulties to give a proper prescription for a tuberculosis patient because antimicrobial susceptibility test requires 4 weeks. To supplement this, we are practicing drug susceptibility testing which allow us to know the sensibility of RMP and INH after 2 or 3 days. But this is only possible when more than 2 positive germ. Therefore, we should practice rapid drug susceptibility testing with culture test. But if media is contaminated by other germs except Mycobacterium tuberculosis, it's hard to interpret result about culture test and to practice antimicrobial susceptibility test and rapid drug susceptibility testing. Because we have to practice again smear, culture test after extracting specimen from the patient, time is consumed and proper patient treatment is postponed. To address these problems and quick patient treatment, rapid drug susceptibility testing is practiced by using GenoType$^{(R)}$ MTDRplus method. As a result of this method we detected sensibility 10 and 7 cases and resistance 0 and 3 cases using RIM and INH respectively with other 1 case toward medicals out of the total 11 test. In conclusion rapid drug susceptibility testing can be used from the contaminated specimen after elimination of contaminated source from culture and proved that it can be practiced for rapid examination of a tuberculosis patient.

• Elastomers and Composites
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• v.44 no.4
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• pp.436-441
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• 2009

Semi flexible polyesters containing aromatic rings and pentamethylene groups in the main chain were synthesized by direct polycondensation reaction. The structures of these polymers were investigated by $^1H$-NMR and FT-IR and the phase transition behavior was characterized with DSC, TGA and crossed polarizing microscope. Inherent viscosities ($\eta_{inh}$) of polymers measured in phenol/p-chlorophenol/1,1,2,2-tetrachloroethane were between 0.46 and 1.30 dL/g. As increasing the linearlity of rigid moieties in polyster, melting transition temperatures ($T_m$) increased and solubilities in organic solvents decreased. P-H, P-mH and P-4H of the polymers formed turbid melts that showed stir-opalescence and nematic phase at the broad anisotropic region, However, P-R, P-C and P-2B did not exhibit any textures related to the liquid crystallinity.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.47-52
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• 2014

A series of liquid crystalline polyesters containing X-shaped mesogenic groups in main chain were synthesized through the solution polymerization of 2,5-di(4-substituted benzoate)hydroquinones and 4,4'-dicarboxy-1,8-diphenoxyoctane. The structures and properties of synthesized polymers were investigated by $^1H$-NMR, FT-IR, differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), polarized optical microscopy (POM) and wide angel X-ray diffraction (WXRD). Inherent viscosities (${\eta}_{inh}$) of polymers were measured between 0.35 and 0.66 dL/g in 1,1,2,2-tetrachloroethane, and they were easily soluble in most of organic solvents used for this experiment. All polymers revealed relatively low melting transition temperature ($T_m$) and crystallinity, and also showed thermotropic nematic liquid crystallinity when they were heated to their melting temperatures. These properties of polymers were presumably due to the presence of the bulky substituting groups on the hydroquinone unit in mesogenic group.

• Asian Spine Journal
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• v.12 no.6
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• pp.1069-1077
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• 2018

Study Design: A case study. Purpose: To assess the chronological changes of the disease-related kyphosis after chemotherapy alone, secondly to clarify the role of growth cartilage in the healed lesion on kyphosis change, and to define the accurate prediction time in assessing residual kyphosis. Overview of Literature: None of the previous papers up to now dealt with the residual kyphosis, stability and remodeling processes of the affected segments. Methods: One hundred and one spinal tuberculosis children with various stages of disease processes, age 2 to 15 years, were the subject materials, between 1971 to 2010. They were treated with two different chemotherapy formula: before 1975, 18 months of triple chemotherapy (isoniazid [INH], para-aminosalicylic acid, streptomycin); and since 1976, 12 months triple chemotherapy (INH, rifampicin, ethambutol, or pyrazinamide). The first assessment at post-chemotherapy one year and at the final discharge time from the follow-up (36 months at minimum and 20 years at maximum) were analyzed by utilizing the images effect of the remaining growth plate cartilage on chronological changes of kyphosis after initiation of chemotherapy. Results: Complete disc destruction at the initial examination were observed in two (5.0%) out of 40 cervical spine, eight (26.7%) out of 30 dorsal spine, and six (19.4%) out of 31 lumbosacral spine. In all those cases residual kyphosis developed inevitably. In the remainders the discs were partially preserved or remained intact. Among 101 children kyphosis was maintained without change in 20 (19.8%), while kyphosis decreased in 14 children (13.7%), and increased in 67 children (66.3%) with non-recoverably damaged growth plate, respectively. Conclusions: It could tentatively be possible to predict the deformity progress or non-progress and spontaneous correction at the time of initial treatment, but it predictive accuracy was low. Therefore, assessment of the trend of kyphotic change is recommended at the end of chemotherapy. In children with progressive curve change, the deformity assessment should be continued till the maturity.

• Tuberculosis and Respiratory Diseases
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• v.85 no.3
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• pp.264-272
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• 2022

Background: The current conventional drug susceptibility test (DST) for Mycobacterium tuberculosis (Mtb) takes several weeks of incubation to obtain results. As a rapid method, molecular DST requires only a few days to get the results but does not fully cover the phenotypic resistance. A new rapid method based on the ability of viable Mtb bacilli to hydrolyze fluorescein diacetate to free fluorescein with detection of fluorescent mycobacteria by flow cytometric analysis, was recently developed. Methods: To evaluate this cytometric method, we tested 39 clinical isolates which were susceptible or resistant to isoniazid (INH) or rifampin (RIF), or ethambutol (EMB) by phenotypic or molecular DST methods and compared the results. Results: The susceptibility was determined by measuring the viability rate of Mtb and all the isolates which were tested with INH, RIF, and EMB showed susceptibility results concordant with those by the phenotypic solid and liquid media methods. The isolates having no mutations in the molecular DST but resistance in the conventional phenotypic DST were also resistant in this cytometric method. These results suggest that the flow cytometric DST method is faster than conventional agar phenotypic DST and may complement the results of molecular DST. Conclusion: In conclusion, the cytometric method could provide quick and more accurate information that would help clinicians to choose more effective drugs.

• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.14-21
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• 1996

Objectives: Although outbreak of MDR Tb has been a recent problem in western countries, it has been a longstanding problem in Korea. The poor outcome of MDR Tb is mainly due to poor compliance, high rate of side reaction of secondary drugs, and limitation in number of available drugs. Thus, to improve the outcome of MDR Tb, it is crucial to make individualized adequate prescription based on the knowledge of the patterns of resistance to each drugs in the community as well as the natural history. The purpose of present study is to evaluate the clinical features of Korean MDR Tb patients including patterns of drug resistance and success rate of treatment which was prescribed according to the sensitivity tests. Methods: Retroscpective analysis of 71 Korean patients with MDR Tb was made. All strains isolated from patients showed resistence to at least two first line drugs. Patients profile, previous treatment history, patterns of drug resistance, outcome of treatment was analysed. Initial treatment regimen was selected according to the previous treatment history and was modified according to the sensitivity reports. The regimen was composed to include at least 4 sensitive drugs when possible. Results: The patients showed resistance to 4.1 drugs on average. 90% of them were resistant to INH and RFP. Among 71 patients, 35 patients(49%) had cavitary lesions in CXR. Treatment outcome was analysed in 55 patients. 35 patients(67%) were improved after treatment and 18 patients(33%) showed treatment failure. 5 patients showed primary resistance. Treatment outcome could be evaluated in 4 of them and all showed improvement after treatment. 14 patients(20%) had to change their regimens due to drug side effects. The most frequent side effect was elevation of liver enzymes(6 patients). Others included dizziness, hyperuricemia, tinnitus, skin rash, GI troubles. More than 50% of side effects developed within 3 months. In repeated drug sensitivity test, the concordance rate of resistance to INH was 100% and RFP 98%. EMB, PZA showed 80% concordance rate. But in the other drugs, the concordances were less than 50%. Operation was done in 5 patient - 1 patients as a adjunctive means of chemotherapy -. In that case, negative conversion of sputum AFB was done. Conclusion: 2/3 patients of multidrug-resistant tuberculosis were improved by appropriate prescription and regular medication suggesting that more aggressive management and monitoring is indicated in multidrug-resistant tuberculosis.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.618-627
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• 1999

Background : Rifampicin (RFP) is a key component of the antituberculous short-course chemotherapy. Usually the RFP resistant M.tuberculosis is also resistant to isoniazid (INH), so the RFP resistance is the marker of multi-drug resistant (MDR) tuberculosis. But unusual cases of mono-RFP-resistant tuberculosis have been recently reported with increasing frequency, especially associated with HIV infection in western countries. Therefore, we conducted a retrospective study to investigate the frequency, causes, and the clinical characteristics of mono-RFP-resistant tuberculosis in Korea. Methods : Of the bacteriologically confirmed and susceptibility-proven 699 pulmonary tuberculosis patients (921 isolates) who visited Asan Medical Center from January 1990 to August 1997, eighteen patients with INH-susceptible and RFP-resistant tuberculosis were evaluated. Previous history of tuberculosis, antituberculous drug compliances, associated systemic illness, drug susceptibility patterns, and clinical outcomes were analysed. And rpoB gene sequencing was done in 6 clinical isolates of M. tuberculosis. Results : The mean age of 18 patients was $43{\pm}14$ years, and the sex ratio is 12:6 (M : F). Sixteen (89%) patients had previous history of tuberculosis. None had diagnosed gastrointestinal disorders, and 2 HIV tests that were performed came out negative. Susceptibility tests were done repeatedly in eleven patients, and six (55%) were mono-RFP resistant repeatedly while five (45%) evolved to MDR tuberculosis. Eight (44%) patients were cured, six (33%) failed, three (17%) were lost to follow-up, and the other one is now on treatment. rpoB gene sequencing showed 5 mutations, codon 531 TCG to TIG mutation in 4 isolates and 526 CAC to TAC in 1 isolate. Conclusion : The clinical characteristics of mono-RFP resistant tuberculosis were similar to that of MDR tuberculosis in Korea where the HIV infection rate is lower than western countries. But some patients with mono-RFP-resistant tuberculous could be cured by primary drug regimens including RFP, suggesting that mono-RFP-resistant tuberculous is a different entity from MDR tuberculosis.