• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.129-136
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• 2011

Microorganisms are the main causative factors of pulpal and periapical diseases, therefore successful endodontic treatment is depend on the effective elimination of intracanal bacterial populations. Many studies have been reported antimicrobial effect of Allyl isothiocyanate (AIT) which the principle ingredient of Horseradish (Armoracia rusticana) root extracts. The purposes of this study are to evaluate the antimicrobial effectiveness of Horseradish root extracts against Enterococcus faecalis in root canals of extracted human teeth and compare to sodium hypochlorite (NaOCl). Extracted human mandibular premolar root canals were infected with E. faecalis for 21 days, and then irrigated with Horseradish root extracts, NaOCl solution and saline. After canal irrigation, first samples (S1) were taken. After first sampling, the canals were additionally incubated 7 days, and then second samples (S2) were taken. The samples were inoculated on EHI agar plate to determine the colony forming units (CFU). 1. Mean values of CFU in S1 were $5.815{\times}10^3$ CFU/ml at Horseradish groups, and $3.465{\times}10^3$ CFU/ml at NaOCI groups. There was no statistically significant differences (p=0.086). 2. Mean values of CFU in S2 were $3.100{\times}10^3$ CFU/ml at Horseradish groups, and $5.252{\times}10^5$ CFU/ml at NaOCI groups. There was statistically significant difference (p<.05). 3. There was no statistically significant differences (p=0.076) between S1 and S2 at Horseradish groups in the mean values of CFU. However, there was statistically significant differences (p<.05) between S1 and S2 at NaOCI groups in the mean values of CFU.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.237-244
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• 2009

When the symptom of periapical infection is not released by mechanical instrumentation. anti-microbial agents including antibiosis become necessary in order to remove microorganisms from the root canal. Since anti-microbial agents of natural origins are currently popular, more natural remedies are being sought out. As it turns out, it is well known isothiocyanates (ITCs) in horseradish root extract have anti-microbial activity from many studies. In this research, anti-microbial effects of horseradish root extract and chlorhexidine, a typical anti-microbial agent, were investigated and compared against two kinds of obligate anaerobes. Fusobacterium nucleatum and Prevotella nigrescens, that are often discovered in infected root canal, and Clostridium perfringens, which is resistant to antibiotics and frequently used as a control strain for antibacterial studies 1. The MIC and MBC of horseradish root extract were ranged from 87 to 470 ppm and from 156 to 625 ppm against three kinds of obligate anaerobes, respectively. Horseradish root extract showed the strongest anti-bacterial activity (MBC, 156 ppm) against F. nucleatum and also showed anti-bacterial activity against antibiotic resistant obligate anaerobes. C. perfringens. 2. The MIC and MBC of chlorhexidine were ranged from 3.12 to 6.25 ppm and 10.94 ppm against three kinds of obligate anaerobes, respectively. 3. The MIC with 87-470 ppm of horseradish root exact has the same growth inhibiting effect as the one of 3.12-6.25 ppm of chlorhexidine. Likewise, the MBC with 156-625 ppm of horseradish has the similar bactericidal effect as 10.94 ppm of chlorhexidine.

• Tuberculosis and Respiratory Diseases
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• v.53 no.1
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• pp.5-16
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• 2002

Background : Though mononuclear phagocytes serve as the final effectors in killing intracellular Mycobacterium tuberculosis, the bacilli readily survive in the intracellular environment of resting cells. The mechanisms through which cellular activation results in the intracellular killing is unclear. In this study, we sought to explore an in vitro model of a low-level infection of human mononuclear phagocytes with MAC and $H_{37}Ra$ and determine the extent of the lymphocyte dependent cytotoxicity of human monocytes and alveolar macrophages. Materials and Methods : The peripheral monocytes were prepared using the Ficoll gradient method from PPD positive healthy people and tuberculosis patients. The alveolar macrophages were prepared from PPD positive healthy people via a bronchoalveolar lavage. The human mononuclear phagocytes were infected at a low infection rate (bacilli:phagocyte 1:10) with MAC(Mycobacterium avium) and Mycobacterium tuberculosis $H_{37}Ra$. Non-adherent cells(lymphocyte) were added at a 10:1 ratio. After 1,4, and 7 days culture in $37^{\circ}C$, 5% CO2 incubator, the cells were harvested and inoculated in a 7H10/OADC agar plate for the CFU assay. The bacilli were calculated with the CFU/$1{\times}10^6$ of the cells and the cytotoxicity was expressed as the log killing ratio. Results : The intracellular killing of MAC and $H_{37}Ra$ within the monocyte was greater in patients with tuberculosis compared to the PPD positive controls (p<0.05). Intracellular killing of MAC and $H_{37}Ra$ within the alveolar macrophage appeared to be greater than that within the monocytes of the PPD positive controls. There was significant lymphocyte dependent inhibition of intracellular growth of the mycobacteria within the monocytes in both the controls and tuberculosis patients and within the macrophages in the controls(p<0.05). There was no specific difference in the virulence between the MAC and the $H_{37}Ra$. Conclusion : This study is an in vitro model of a low-level infection with MAC and $H_{37}Ra$ of human mononuclear phagocytes. The intracellular cytotoxicity of the mycobacteria within the phagocytic cells was significantly lymphocyte dependent. During the 7 days culture after the intracellular phagocytosis, the actual confinement of the mycobacteria was observed within the monocytes of tuberculosis patients and the alveolar macrophages of the controls as in the case of adding lymphocytes.

• KSBB Journal
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• v.14 no.5
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• pp.593-599
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• 1999

In this study, optimal conditions to infect CD34 positive cells containing hematopoietic stem cells obtained from cord blood and bone marrow were found using two different retroviral vectors expressing human growth hormone (hGH) and $\beta$-galactosidase. CD34 positive cells were successfully infected with recombinant retroviruses only when the CD34 positive cells were co-cultured with packaging cells secreting recombinant retroviruses. To find the highest infection efficiency for the gene transfer, CD34 positive cells from cord blood were co-cultured with packaging cells secreting recombinant retroviruses encoding E. coli lacZ gene. The highest infection efficiency was obtained when CD34 positive cells were cultured for 3 days, and then co-culturing was done for another 2 days. When CD34 positive cells from bone marrow were co-cultured with packaging cells secreting recombinant retroviruses encoding hGH gene, the maximum amount of hGH was also secreted at the same conditions found above, i.e. 3 days of culture and 2 days of co-culture. These results show that there are optimal conditions for the gene transfer into hematopoietic stem cells regardless of sources of target cells or retroviral vectors used to infect.

• Journal of Korean Society of Forest Science
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• v.81 no.2
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• pp.191-199
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• 1992

This study was conducted to identify fungi causing canker dieback and melanconis disease of walnut trees (Juglans sinensis Dode) in Korea and clarify the pathogenicity and factors affecting the growth of these fungi. The causal fungi isolated from infected walnut stems and branches obtained from the commercial walnut orchards in Cheonwon, Goesan, Youngdong were identified as Botryosphaeria dothidea (Moug, ex Fries) Casati et de Notaris, Phoniopsis albobestita Fairman, Melanconis juglandis (Ellis et Everhart) Graves and their pathogenicity was confirmed by inoculation test. Temperature range for minimum growth of three fungi was 8 to $35^{\circ}C$ and the optimum temperature for mycelial growth of B. dothidea and P. albobestita ranged from 25 to $30^{\circ}C$, while the optimum temperature for M. juglandis ranged from 20 to $25^{\circ}C$. The optimum pH range for mycelial growth of P. albobestita was 4.0~5.0 and that for B. dothidea and P. juglandis 4.0~8.0. Glucose, sucrose, starch or maltose, as a carbon source, and histidine or potassium nitrate as a nitrogen source were more suitable compounds for growth. of B, dothidea, P. albobestita grew very well on the medium containing alanine and potassium nitrate as a nitrogen source, and utilized well glucose and sucrose as a carbon source. M. juglandis grew well on the medium containing glucose, and sucrose as a carbon source and utilized well potassium nitrate as a nitrogen source. The dieback and twig blight caused by P. albobestita were more severe than those by B. dothidea and M. juglandis at three locations investigated. Incidences of canker and dieback were more frequently observed in aged walnut trees than in young ones.

• Neonatal Medicine
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• v.18 no.2
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• pp.265-271
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• 2011

Purpose: Extended spectrum $\beta$-lactamase (ESBL) producing organism is an important cause of infections in the neonatal intensive care unit (NICU) since 1990s. The aim of this study is to investigate the differences of clinical characteristics and hematologic studies between neonates with ESBL-positive organism and those with ESBL-negative organism. Methods: The subjects included 48 neonates admitted to NICU at Inje University Sanggye Paik Hospital from January 2005 to September 2010, from whom a total of 58 Escherichia coli or Klebsiella pneumonia were detected. The data were categorized in 2 groups, neonates with ESBL-positive and ESBL-negative. We compared clinical characteristics and hematologic studies between two groups. Results: Of 48 neonates and 53 isolates, ESBL-positive were 18 neonates and 20 isolates. Both ESBL-positive and ESBL-negative isolates were largely found in urine, each with 10 and 23. Of 20 ESBL-positive isolates, 13 (65%) and 7 (35%) were ESBL producing Escherichia coli and Klebsiella pneumonia, respectively. ESBL-positive neonates were associated with low 1 and 5 minutes Apgar scores (P=0.002 and P=0.001, respectively), more uses of oxygen (56% vs. 27%; P=0.005), longer duration of oxygen uses (15.8${\pm}$38.43 days vs. 4.3${\pm}$12.5 days; P=0.008) and more frequent anemia (33% vs. 7%; P=0.040). Conclusion: ESBL-positive neonates may have more anemia and lower Apgar score at birth. We can consider the use of cabapenem earlier if infant with previous antibiotics is confirmed to be infected with ESBL-positive organisms.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.353-364
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• 2020

Recently in Korea, soybean harvesting has been delayed due to rainfall during the harvesting season, resulting in a reduction in yield and seed quality. This study was conducted to analyze the changes in yield and seed quality during delayed harvest with rainfall treatment using different harvesting methods, including field harvesting and polyethylene film covering after cutting fully-matured soybean plants (PE covering after cutting), with two major Korean soybean cultivars (Glycine max L), Pungsannamulkong and Daewonkong. The shattering rate of Pungsannamulkong, which is higher than that of Daewonkong, increased up to 41.8% when the harvest was delayed for 40 days without rainfall treatment by harvesting with PE covering after cutting. The weight of 100 seeds tended to decrease slightly as harvesting was delayed. When Daewonkong was harvested using the PE covering after cutting method with rainfall treatment, the yield decreased to the lowest level with a 0.8 kg ha^-1 daily reduction rate. Pungsannamulkong showed the lowest yield when harvested using PE covering after cutting without rainfall treatment with a 3.4 kg ha^-1 daily reduction rate. The infected seed rate increased according to the harvest delay in both cultivars, and significant differences were observed according to rainfall treatment and harvesting method. The germination rate was maintained above 95% even after 40 days of delayed harvest if there was no rainfall treatment. However, with rainfall treatment, the germination rate was significantly lowered as harvesting time was delayed. In the field harvesting with rainfall treatment, the germination rate decreased to 77.2% for Daewonkong and 76.5% for Pungsannamulkong after 40 days of harvest delay. For the 100-seed weight, effects of individual treatments and interactions between treatments were not observed. In contrast, the effect of interactions between treatments on the shattering rate was significant in both cultivars, indicating that the shattering rate had the greatest impact on the yield changes during delayed harvest.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.906-912
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• 2004

Helicobacter pylori infection is highly prevalent, as high as 2/3 of whole population infected, in Korea. H. pylori infection initiates inflammation by induction of interleukin-8 through type IV secretion of CagA. It was recently suggested that induction failure of IL-8 is not associated with defect in cag PAI but associated with cagE locus diversity. This study was designed to investigate ability of 11-8 in-duction according to sequence variation within the cagE gene, cagA TP motifs and vacA m-types in vitro study using AGS cell-line, and to evaluate its association with different clinical outcome. Seventy-four H. pylori stains were isolated from 23 patients with gastric cancer (Ca), 24 subjects with gastritis (G) and 27 patients with duodenal ulcer (Du) in Kangnam St. Mary's Hospital, Seoul, Korea. cagE gene diversity was confirmed by the PCR-RFLP methods with MboI/NlaIII and tyrosine phosphate motifs (TPMs) of cagA was determined TPM-A and C by using DdeI/Tsp5091 restriction enzyme and TPM-B was determend by Real time PCR the method of Owen et al. and IL-8 was measured by ELISA assay. IL-8 activity was positively detected in 59 among 74 strains $(79.7\%)$. IL-8 secretion was significantly increased in MboI A and MboI B type compared to MboI C type and in MboI/NlaIII A-C and B-C type than C-C type. 1L-8 activity was not associated with either the number or composition of cagA tyrosine phosphorylation motifs and vacA m-type. There was no significant difference in IL-8 activity among patient groups. cagE gene diversity is thought to be mainly associated with the induction of IL-8 in H. pylori infection.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.3
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• pp.217-224
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• 2016

Acinetobacter baumannii (A. baumannii) is prevalent in hospital environments and is an important opportunistic pathogen of nosocomial infection. It is known that this pathogen cause herd infection in hospitals, and the mortality rate is remarkably higher for patients infected with this pathogen and already have other underlying diseases. Herein, we investigated the antibiotic resistance rate and the type of resistance genes in 85 isolates of multi-drug resistant A. baumannii from the samples commissioned to laboratory medicine in two university hospitals-in hospital A and hospital B-located in Cheonan and Chungcheong provinces, respectively, in Korea. As a result, $bla_{OXA-23-like}$ and $bla_{OXA-51-like}$ were detected in 82 stains (96.5%). These 82 strains of $bla_{OXA-23-like}$ producing A. baumannii were confirmed with the ISAba1 gene found at the top of the $bla_{OXA-23-like}$ genes by PCR, inducing the resistance against carbapenemase. The armA, AME gene that induces the resistance against aminoglycoside was detected in 34 strains out of 38 strains from Hospital A (89.5%), and in 40 strains out of 47 strains from Hospital B (85.1%), while AMEs were found in 33 strains out of 38 strains from Hospital A (70.2%) and in 44 strains out of 47 strains in Hospital B (93.6%). Therefore, it was found that most multi-drug resistant A. baumannii from the Cheonan area expressed both acethyltransferase and adenyltransferase. This study investigated the multi-drug resistant A. baumannii isolated from Cheonan and Chungcheong provinces in Korea, and it is thought that the results of the study can be utilized as the basic information to cure multi-drug resistant A. baumannii infections and to prevent the spread of drug resistance.

• The Journal of the Korean Society for Microbiology
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• v.7 no.1
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• pp.29-41
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• 1972

To grow Myocbacterium leprae in cultured mouse peritoneal macrophages, studies were made with trypsin-purified Myco. laprae on 1) the dynamics of infection of mouse peritonal macrophages in vivo with Myco. leprae by intraperitoneal inoculation, 2) growth experiment of Myco. leprae in cultured mouse peritoneal macrophages by in vivo infection and in vitro cultivation and 3) the observation of pathological changes in spleens of mice induced by intraperitoneal inoculation of Myco. leprae. Results are summarized as follows; 1. Continuing and significant decreases were observed in the numbers of both acid-fast bacilli in cultured macrophage and of macrophages harboring.acid-fast bacilli by the length of inter vats between the time of intraperitoneal inoculation of Myco. leprae and the time of initiation of macrophage culture. 2. No evidence of multiplication of Myco. leprae in the peritoneal macrophages in vivo was found up to 5 months after intraperitoneal inoculation. 3. With cultures of macrophages made 24 hours and 1 week after intraperitoneal inoculation of Myco. leprae and maintained in vitro up to 2 to 3 months, microscopic examination of the stained preparations of cultured macrophages indicated that an apparent increase in the number of acid-fast bacilli in the macrophages did occur. 4. Quantitative experiment with in vivo infected-in vitro cultured macrophages revealed certain features of increase in the number of total acid-fast bacilli in the cultured macrophages 7 and 9 weeks after initiation of the cultures. 5. Pathological changes in the spleens mice inoculated with Myco. leprae were of mainly degenerative nature in the red pulp. No multiplication of Myco. leprae was observed in the spleens of mice up to 5 months after intraperitoneal inoculation.