• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.367-374
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• 2000

The composition of dissolved gases and nutrients in a liquid medium were determined for establishment of the optimum conditions for in vitro culture of Helicobacter pylori. A microaerobic condition facored by the organism was prepared by adjusting the partial pressure of the gas, agitation speed, and viscosity of the medium. The gaseous concentrations were controlled by utilizing CampyPak Plus that reduced oxygen while augmenting carbon dioxide. Agitation of the broth facilitated the oxygen transfer to the cells, yet inhibited the growth at high rates. An increase of viscosity in the medium repressed the culture although this variable was relatively insignificant. The chemical constituents of the liquid broth were examined to establish an economic model for H. pylori cultivation. The microbe required a neutral pH for optimum growth, and yet was also able to proliferate in an acidic condition, presumably by releasing the acidity-modulating enzyme, urease. Cyclodextrin and casamino acid were investigated as growth enhancers in place of serum, while yeast extract unexpectedly inhibited the cells. A low concentration of glucose, the unique carbon source for the organism, increased the cell density, yet high concentrations resulted in an adverse effect. Under optimally dissolved gas conditions, the cell concentration in brucella broth supplemented with serum substitutes and glucose reached $1.6{\times}10^8$ viable cells/ml which was approximately 50% higher than that obtained in the liquid medium added with only cyclodextrin or serum.

• The Journal of Internal Korean Medicine
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• v.20 no.1
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• pp.99-110
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• 1999

Effects of Chiyangtang(CYT) on H. pylori-induced increase of interleukin 8 and interleukin 1 gene expression was studied in Kato Ⅲ cell line, a human stomach epithelial cell line. Treatment of H. pylori to the cell culture signifant!y increased IL-8 and IL-1 mRNA synthesis. When CYT was added along with H. pylori, the increase of IL-8 and IL-1 mRNA synthesis was blocked. Activation of transcription factor $NF-{\kappa}B$ and AP-1 which were known to important in IL-8 and IL-1 gene expression was also studied using chloramphenicol acetyltransferase(CAT) assay. Treatment of H. pylori increased activation of $NF-{\kappa}B$ and AP-l and CYT effectively protected the activation. Electrophoretic mobility shift assay suggested that CYT effectively inhibited DNA binding of $NF-{\kappa}B$ and AP-l to their cognate site. These results suggested that CYT could prevent stomach diseases through the down regulation of IL -8 and IL-l gene expression which might be mediated by the inhibition of $NF-{\kappa}B$ and AP-1 activities and their binding to DNA.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.955-960
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• 2005

Resistance to metronidazole, a key component of therapies against Helicobacter pylori, is common in clinical isolates. Resistance generally requires inactivation of rdxA (HP0954), and sometimes also frxA (HP0642), two related nitroreductase genes. Here we studied the effect of resistance to metronidazole on fitness of the gastric pathogen H. pylori. The effect of metronidazole resistance for H. pylori in culture was assessed first by looking at colonies formed by freshly constructed mutant derivatives of H. pylori strain 26695. Mutations resulting in metronidazole resistance caused premature death of H.pylori in stationary phase, but had no significant effect on early exponential growth. The effect of nitroreductase deficiencies on fitness in vivo was tested by infecting C57BL/6 mice with 1:1 mixtures of SS1 wild type and its isogenic metronidazole resistant derivatives. Inactivation of rdxA caused an inability to colonize mice in SS1 H. pylori strain. Derivatives of a metronidazole resistant strain that survived better in stationary phase, although remaining metronidazole resistant, could again colonize mice. In conclusion, metronidazole resistance diminishes H. pylori's fitness, but their costs can be suppressed by additional mutation.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.6089-6092
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• 2015

Background: The prevalence of metronidazole-resistant H. pylori is almost 50% in Thailand which severely limits the use of this drug for eradication therapy. The aims of this study were to evaluate the efficacy and safety profiles of 7-day bismuth-based quadruple therapy including metronidazole as an initial treatment for H. pylori infection in a high metronidazole resistance area. Materials and Methods: This study was performed at Thammasat University Hospital and King Chulalongkorn Memorial Hospital during January 2009 to October 2010. Patients with non-ulcer dyspepsia (NUD) with active H. pylori infection were assigned to receive seven days of quadruple therapy (pantoprazole 40 mg bid, bismuth subsalicylate 1,048 mg bid, amoxicillin 1 gm bid and metronidazole 400 mg tid). H. pylori infection was defined as positive H. pylori culture or two positive tests (rapid urease test and histology). Antibiotic susceptibility test for metronidazole by Epsilometer test (E-test) was performed in all positive cultures. At least four weeks after treatment, $^{13}C$ urea breath test ($^{13}C-UBT$) was performed to confirm H. pylori eradication. Results: A total of 114 patients were enrolled in this study, 50 males and 64 females with a mean age of 49.8 years. All 114 patients had a diagnosis of NUD. Overall eradication as confirmed by negative $^{13}C-UBT$ was achieved in 94 out of 114 patients (82.5%). 44 patients had positive cultures and success for E-test. In vitro metronidazole resistance was observed in 22/44 (50%) patients. Eradication rate in patients with metronidazole resistant strains was 16/22 (72.7%) and 20/22 (90.1%) with metronidazole sensitive strains (72.7% vs 90.1%, p-value=0.12; OR=3.75 [95%CI=0.6-31.5]). Minor adverse reactions included nausea, bitter taste, diarrhea and black stools but none of the patients dropped out from the study. Conclusions: Initial treatment with 7-day bismuth-based quadruple therapy including metronidazole, amoxycillin and pantoprazole is highly effective and well tolerated for metronidazole-sensitive H. pylori infections. However, the efficacy markedly decline with metronidazole resistance. Longer duration of this regimen might be required to improve the eradication rate and larger multi-center studies are needed to confirm this hypothesis.

• Journal of Oral Medicine and Pain
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• v.30 no.3
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• pp.319-328
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• 2005

To examine whether HSV, VZV, H. pylori and Candida that are known to be microorganisms causing ulcerative disease in oral cavity and have the relatively high contigiousness are detected in saliva of patients with RAU and related to the development with RAU, PCR and culture were performed on the saliva of 29 patients with RAU and 29 control subjects who visited the Department of Oral Medicine, Dental Hospital, Chosun University. The results were obtained as follows; 1. HSV DNA was detected in 41.4% patients with RAU, and 55.2% control subjects, however, a significant difference between the two groups was not detected, (P>0.05), and VZV DNA was not detected in both groups. 2. H. pylori DNA was detected in 27.6% patients with RAU, and 48.3% control subjects, however, a significant difference between the two groups was not detected (P>0.05). 3. Candida was cultured in 13.8% patients with RAU, and 6.9% control subjects, however, a significant difference between the two groups was not detected (P>0.05). This results suggest that HSV, VZV, H. pylori and Candida can not be regarded to play a direct role in the development of RAU. Thus it is considered that in future, on a larger sample, also, it has to be examined whether other microorganisms acts as a trigger factor of the development of RAU.

• The Korean Journal of Gastroenterology
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• v.72 no.5
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• pp.229-236
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• 2018

Accurate diagnosis of Helicobacter pylori (H. pylori) infection is mandatory for the effective management of many gastroduodenal diseases. Currently, various diagnostic methods are available for detecting these infections, and the choice of method should take into account the clinical condition, accessibility, advantage, disadvantage, as well as cost-effectiveness. The diagnostic methods are divided into invasive (endoscopic-based) and non-invasive methods. Non-invasive methods included urea breath test, stool antigen test, serology, and molecular methods. Invasive methods included endoscopic imaging, rapid urease test, histology, culture, and molecular methods. In this article, we provide a review of the currently available options and recent advances of various diagnostic methods.

• Clinical and Experimental Pediatrics
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• v.49 no.3
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• pp.268-272
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• 2006

Purpose : The reinfection rate of H. pylori reported before $^{13}C$-urea breath test($^{13}C$-UBT) era was higher than that of the post $^{13}C$-UBT era. Children are usually reluctant to receive invasive endoscopic evaluation for the reinfection of H. pylori, particularly when they are asymptomatic. The aim of the study is to discover the reinfection rate by different diagnostic tests, and to find out what causes the difference. Methods : Children confirmed to be eradicated from H. pylori were included in the study. Reinfection was evaluated by endoscopic biopsy based tests(n=34, mean age $11.5{\pm}3.7$ years) and/or a $^{13}C$-UBT(n=38, mean age $10.0{\pm}3.6$ years) at the time of 18 months after eradication. At first visit, H. pylori infection had been diagnosed by positive results from a rapid urease test, Giemsa stain and Warthin-Starry stain and/or a positive culture. Eradication was defined as negative results from all above tests 1-3 months after eradication therapy. Results : Reinfection rate by endoscopic biopsy based tests was 35.3 percent(12/34). All patients had abdominal symptoms(P=0.000). Reinfection rate was 13.2 percent(5/38) by a $^{13}C$-UBT. Reinfection rate was higher in children with abdominal symptoms(P=0.008). There was no evidence that reinfection rate depended on the sex(P=0.694), age(P=0.827), diseases(peptic ulcers vs gastritis, P=0.730) and eradication regimen(P=0.087). Conclusion : Helocibacter pylori reinfection rate in Korean children was 13.2 percent per 18 months by a non-invasive test or $^{13}C$-UBT. Accurate determinations of the reinfection rate in children is affected by the compliance of the diagnostic tests. Non-invasive tests should be considered to investigate the reinfection rate in children.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.288-299
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• 2015

Lactobacillus brevis BK11 obtained from Baikkimchi was selected to study the effects of culture medium, initial pH, atmosphere composition, incubation temperature and time, and prebiotics on growth and production of antimicrobial substances. Growth and antimicrobial substances production of L. brevis BK11 were significantly higher in MRS broth than in BHI or M17 broth. The production of cell mass, lactic acid, and bacteriocin by BK11 strain was at maximum in MRS broth adjusted to pH 6.0. Aerobic and microaerobic conditions were favored cell growth and antimicrobial substances production than anaerobic condition. Biomass and lactic acid production and antimicrobial substances activity of BK 11 were significantly better at 30 and $37^{\circ}C$ than at $25^{\circ}C$. Growth of the strain BK11 entered the stationary growth stage at 24 h after inoculation, and decreased after 36 h. Antimicrobial activities of cell-free culture supernatant and bacteriocin solution were highest when cultured in MRS broth with an initial pH 6.0 for 24-30 h at $37^{\circ}C$. In addition, the highest cell number and lactic acid and bacteriocin production were recorded in the presence of 1 and 2% (w/v) fructooligosaccharide (FOS), however, inulin and raffinose did not affect biological and physicochemical characteristics and antimicrobial activities of L. brevis BK11 cultures. According to these results, production of antimicrobial substances by L. brevis KB11 was closely associated with cell density. Under optimal conditions for antimicrobial substances production, L. brevis BK11 effectively inhibited the growth of Helicobacter pylori ATCC 43504.

• Gut and Liver
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• v.12 no.6
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• pp.648-654
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• 2018

Background/Aims: Dual priming oligonucleotide-based multiplex polymerase chain reaction (DPO-based PCR) can detect the presence of clarithromycin resistance without culture. The aim of this study was to investigate the cost-effectiveness of DPO-based PCR for Helicobacter pylori eradication. Methods: From 2015 to 2016, medical records of patients who received H. pylori eradication therapy were analyzed. Patients were divided into two groups: tailored group patients who were treated based on DPO-based PCR and empirical group patients. Eradication rate and medical cost, including diagnostic tests, eradication regimens, and $^{13}C$-urea breath tests, were compared between the two groups. Cost for one successful eradication was calculated in each group. The expected cost of eradication for empirical treatment was investigated by varying the treatment duration and eradication rate. Results: A total of 527 patients were analyzed (tailored group 208, empirical group 319). The eradication success rate of the first-line therapy was higher in the tailored group compared to that in the empirical group (91.8% vs 72.1%, p<0.01). The total medical cost for each group was $114.8{\pm}14.1U.S.$ dollars (USD) and $85.8{\pm}24.4USD$, respectively (p<0.01). The total medical costs for each ultimately successful eradication in the tailored group and in the empirical group were 120.0 USD and 92.4 USD, respectively. The economic modeling expected cost of a successful eradication after a 7- or 14-day empirical treatment was 93.8 to 111.4 USD and 126.3 to 149.9 USD, respectively. Conclusions: Based on economic modeling, the cost for a successful eradication using DPO-based PCR would be similar or superior to the expected cost of a successful eradication with a 14-day empirical treatment when the first-line eradication rate is ${\leq}80%$.

• YAKHAK HOEJI
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• v.49 no.3
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• pp.237-243
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• 2005

Present study was performed for the development of a new supplementary product with gastroprotective effect. The preliminary screening were conducted for the effects of HCl-ethanol-induced gastric lesions in rats. Samples were aloe gel, active hexose correlated compound (AHCC) mentioned that have GI protective property and pulmuone healthy aloe gel (PHAG) that mixture of natural products from Pulmuone company. Aloe gel significantly inhibited HCl-ethanol-induced gastric lesions at the oral dose of 5 ml/kg. AHCC showed the strongest effectiveness at the oral dose of 1,200 mg/kg. PHAG also showed the significant effects at the oral dose of 10, 20 g/kg. In pylorus ligated rats, the treatments of aloe gel, AHCC and PHAG showed decrease in the volume of gastric secretion and acid output. And aloe gel, AHCC and PHAG significantly suppressed the aspirin-induced ulcer and chronic ulcer in pylorus ligated rats. The treatments of aloe gel and PHAG significantly reduced acetic acid-induced ulcer at the oral dose of 5 ml/kg and 10 g/kg for 12 days. In this study; we have found that PHAG had significant improvement in acute gastritis and ulcer at the dose of 20 g/kg and in chronic gastritis and ulcer at the dose of 10 g/kg. Also we evaluated the anti-bacterial activity against H. pylori treated with aloe gel, AHCC and PHAG. PHAG had a equivalent anti bacterial activity with ampicillin against H. pylori at the dose of 1 g/kg.