• International Journal of Oral Biology
• /
• 제46권1호
• /
• pp.60-65
• /
• 2021

Dental health care workers (DHCW) are at a risk of occupational exposure to Helicobacter pylori from the aerosolized oral biofilms and saliva of patients. We designed this study to investigate the prevalence of H. pylori in the oral biofilms of a group of dental and non-dental undergraduates from Sri Lanka. After obtaining informed consent, oral biofilms were collected from 38 dental undergraduates (19 males and 19 females) undergoing clinical training and 33 non-dental undergraduates (14 males and 19 females). The participants were in the age range of 22-27 years and had healthy periodontium. Total DNA from the oral biofilms were extracted, and H. pylori DNA was detected using polymerase chain reaction (PCR) amplification of 16S rRNA gene of H. pylori using JW22-JW23 primers, and the results were confirmed using PCR amplification of H. pylori-urease specific HPU1-HPU2 primers. Out of 71 participants, 11 (28.95%) dental and 3 (9.09%) non-dental undergraduates had H. pylori in their oral biofilms indicating an overall prevalence rate of 19.72% (14/71). Thus, the prevalence of H. pylori in oral biofilms was significantly higher in dental undergraduates than in non-dental undergraduates (p < 0.05). An odds ratio of 4.07 indicated that dental undergraduates were four times more likely to harbor H. pylori in their oral biofilms than non-dental undergraduates. Foregoing data support the fact that there may be greater occupational risk of exposure to H. pylori for dental undergraduates during clinical training than that for non-dental undergraduates, warranting meticulous infection control practices during clinical dentistry.

• Clinical Endoscopy
• /
• 제56권1호
• /
• pp.75-82
• /
• 2023

Background/Aims: The etiology of superficial non-ampullary duodenal epithelial tumors (SNADETs) remains unclear. Recent studies have reported conflicting associations between duodenal tumor development and Helicobacter pylori infection or endoscopic gastric mucosal atrophy. As such, the present study aimed to clarify the relationship between SNADETs and H. pylori infection and/or endoscopic gastric mucosal atrophy. Methods: This retrospective case-control study reviewed data from 177 consecutive patients with SNADETs who underwent endoscopic or surgical resection at seven institutions in Japan over a three-year period. The prevalence of endoscopic gastric mucosal atrophy and the status of H. pylori infection were compared in 531 sex- and age-matched controls selected from screening endoscopies at two of the seven participating institutions. Results: For H. pylori infection, 85 of 177 (48.0%) patients exhibited SNADETs and 112 of 531 (21.1%) control patients were non-infected (p<0.001). Non-atrophic mucosa (C0 to C1) was observed in 96 of 177 (54.2%) patients with SNADETs and 112 of 531 (21.1%) control patients (p<0.001). Conditional logistic regression analysis revealed that non-atrophic gastric mucosa was an independent risk factor for SNADETs (odds ratio, 5.10; 95% confidence interval, 2.44-8.40; p<0.001). Conclusions: Non-atrophic gastric mucosa, regardless of H. pylori infection status, was a factor independently associated with SNADETs.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제2권2호
• /
• pp.147-152
• /
• 1999

목 적: H. pylori 감염률은 생활수준과 밀접한 관계가 있어 경제적으로 어려울수록 감염률이 높아지며 사회생활을 하면서 나이가 증가함에 따라 같이 올라간다. 소아에 있어서 선진국에서는 5% 미만의 감염률을 보이고 있고 우리나라에서는 6세에서 15세까지의 정상아동에 16.5%의 감염률이 보고된 바 있다. 부모연령의 감염률이 높은 우리나라에서 5세 이하 정상아동에서의 H. pylori 감염률은 혈액채취 등의 어려움으로 현재까지 거의 조사되어 있지 않아 H. pylori 특이 IgG 항체검사를 이용, H. pylori의 감염률을 알아보고자 하였다. 방 법: 1995년 서울시내 3곳의 어린이집을 방문하여 2세에서 5세까지의 220명(2세 24명, 3세 54명, 4세 95명, 5세 47명)에 대하여 혈액을 채취하고 ELISA를 이용한 IgG GAP test로 H. pylori의 감염률을 조사하였다. 결 과: 1) 총 220명중 양성은 2세 1명, 3세 2명, 4세 1명, 5세 1명의 총 5명으로 양성률은 2.3%였다. 2) 약양성(equivocally probable positive)은 2세 3명, 3세 3명, 4세 4명, 5세 3명의 총 13명으로 220명중 5.9%였다. 결 론: 우리나라 2세에서 5세까지의 정상아동에 있어서 H. pylori의 감염률은 2.3~8.2%로 생각되어지며 선진국에 비교하면 아직도 높은 수치로 향후 가족내 감염 등 집단감염과 사회경제적 환경의 변화에 따른 감염률의 추이에 대해 지속적인 연구가 필요할 것으로 본다.

• Clinical and Experimental Pediatrics
• /
• 제49권2호
• /
• pp.136-143
• /
• 2006

The relationship between H. pylori(Hp) infection and recurrent abdominal pain(RAP) in children is not clear. Current data in the literature regarding a causal relationship between Hp infection and childhood RAP are conflicting. However, meta-analysis and most of the recently published studies have not supported an association between Hp infection and an increased prevalence of abdominal pain. Most published studies have some problems and have been criticized on methodological grounds. Most of the existing studies have not been designed to include double-blind placebo controls. And, because of the low incidence of Hp infection in children, they have a problem of obtaining sufficient numbers of the Hp infected children. There is also a concern about the heterogeneity of testing methodology in the studies and diagnostic accuracy problems of the non-invasive tests such as low sensitivity of the serology tests and false positive results of the UBT in children. And conflicting results may be explained, in part, by the poor definition of RAP or dyspepsia for the study subjects. To date, no consensus exists for the treatment of Hp-infected children with RAP. Some authors suggest the clinical efficacy of Hp. But others suggest that eradication of Hp is not associated with improvement of RAP. The problem of the most treatment studies is that they had usually no control groups and the number of the subjects was small. In order to make reasonable decisions about treatment of Hp infection in children with RAP, long-term, randomized, double blind, well controlled studies in large numbers of children will be required.

• 한국미생물·생명공학회지
• /
• 제25권3호
• /
• pp.240-247
• /
• 1997

Bacillary is the most common form of H. pylori observed during human infection. However, it is known that the morphology change of H. pylori from bacillary to coccoid can be occurred with a response to the environmental stresses such as the nutrient depletion, accumulation of toxic metabolites, pH alteration, and exposure to antimicrobial agents. The coccoid form of H. pylori, which is viable but non-culturable in vitro, seems to be the major cause of antibiotic resistancy and high reinfectability of H. pylori. In this regard, we studied the environmental factors that can induce the morphological change in vitro of H. pylori, and the change of fatty acid composition of plasma membrane. The morphological change from bacillary to coccoid could be observed with the depletion of nutrients, pH variation and reactive oxygen species added in the culture media. This morphologic conversion was paralleled by a dramatic decrease in unsaturated fatty acids and an increase in saturated fattv acids of plasma membrane. The change in composition of membrane fatty acid seems to be a kind of protection mechanism of H. pylori against these environmental stresses.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권13호
• /
• pp.5245-5247
• /
• 2014

Background: Helicobacter pylori (H.pylori) is one of the most important causes of dyspepsia and gastric cancer and diagnosis can be made by invasive or non-invasive methods. The Atlas Helicobacter pylori antigen test is a new rapid non-invasive method which is simple to conduct. The aim of this study was to determine its sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy. Materials and Methods: This prospective study was conducted between July 2012 and December 2013. Stool samples of 59 dyspeptic patients who underwent upper endoscopy were evaluated for H. pylori stool antigen. Results: From the 59 patients who participated in this study, there were 36 (61%) males and 23 (39%) females. H. pylori was diagnosed in 24 (40.7%) gastric biopsies, 22 (91.7 %) of these being positive for the Atlas H. pylori antigen test. The sensitivity, specificity, PPV, NPV and accuracy were 91.7%, 100%, 100%, 94.6% and 96.6% respectively. Conclusions: The Atlas H. pylori antigen test is a new non-invasive method which is simple to perform and avails reliable results in a few minutes. Thus it can be the best option for the diagnosis of H. pylori infection due to its high sensitivity and specificity.

• Asian Pacific Journal of Cancer Prevention
• /
• 제17권3호
• /
• pp.917-921
• /
• 2016

However, the incidence of gastric cancer (GC) has been decreased in past decades; GC is the second cause of cancer related death in the world. Evidence has illustrated that several factors including Helicobacter pylori (H. pylori) infection, host genetics, and environmental factors (smoking and particularly diet) may play a crucial role in gastric carcinogenesis. It has been demonstrated that high consumption of fresh fruits, vegetables, high level of selenium and zinc in drinking water, sufficient iron, and cholesterol protect against GC, while; smoked, pickled, and preserved foods in salt, and nitrites increase the risk of GC. Epidemiological studies have also proved that H. pylori infection and a high salt diet could independently induce atrophic gastritis and intestinal metaplasia. Recently, studies have been demonstrated that dietary factors directly influence H. pylori virulence. The use of appropriate diet could reduce levels of H. pylori colonization or virulence and prevent or delay development of peptic ulcers or gastric carcinoma. This is attractive from a number of perspectives including those of cost, treatment tolerability, and cultural acceptability. This review will describe new insights into the pathogenesis of H. pylori in relation to environmental factors, especially dietary, not only to find the developed means for preventing and treating GC, but also for understanding the role of chronic inflammation in the development of other malignancies.

• Nuclear Medicine and Molecular Imaging
• /
• 제43권6호
• /
• pp.572-576
• /
• 2009

목적: 분화 갑상선암으로 갑상선전절제술 이후 고용량 방사성요오드치료(HD-RIT)를 시행하는 환자에서 Helicobacter (H) pylori 감염에 대한 유병률을 알아보고 HDRIT가 H. pylori 제균에 영향을 미치는 지를 알아보고자 하였다. 대상 및 방법: 2008년 6월부터 2009년 2월까지 분화 갑상선암으로 갑상선전절제술과 중앙과 주변 림프절제 거술 후 최초 HD-RIT를 시행한 환자 199명(남:녀=33:166, 나이 $46.7{\pm}12.3$세)과 건강검진을 목적으로 요소호기검사(UBT)를 시행한 건강한 156명(남:녀=57:99, 나이 $48.7{\pm}14.3$세)을 대상으로 하였다. HD-RIT를 받기 위하여 입원한 환자에서 H. pylori 감염 유무를 확인하기 위하여 방사성요오드 투여 1시간 전에 UBT를 시행하였다. HDRIT 시행전 UBT에서 양성을 보인 환자에서는 HD-RIT 시행 후 4주 경과시에 추적 UBT를 시행하였다. HD-RIT 시행전과 추적 UBT 측정치의 변화는 paired Student's t test를 이용하여 p값이 0.05 미만인 경우를 통계적으로 유의 하다고 판정하였다. 결과: 건강한 대조군 156명에서 시행된 UBT에서 115명(73.7%)에서는 양성이었고, 41명(26.8%)은 음성이었다. 분화 갑상선암으로 갑상선절제술을 시행받은 대상환자 199명 중에서 103명(51.8%)이 치료전 UBT에서 양성이었고, 96명 (48.2%)이 음성으로 대조군에 비하여 H. pylori 유병율이 낮았다. 양성을 보인 103명 중 80명에 대해서 HD-RIT 후 추적 UBT를 시행하였고 76명(95.0%)에서는 여전히 양성을 보였고, 4명(5.0%)만이 음성으로 변하였다. 지속적으로 추적 UBT에서 양성을 보인 76명 중 26명 (34.2%)에서는 HD-RIT 후에 측정값이 증가하였으며 증가정도는 $66{\pm}66.1\;dpm$ 이었다. 반면에 49명(64.5%)에서는 HD-RIT 후에 측정값이 감소하였으며 감소정도는 $153.3{\pm}157.1\;dpm$ 이었고, 1명(1.3%)은 방사성 요오드 치료전후 같은 값을 보였다. 결론: 갑상선암 환자에서 H. pylori 유병률은 건강한 성인에 비하여 높지 않으며, HD-RIT가 H. pylori의 제균에 의미있는 효과는 없으나 H. pylori 감염의 정도나 분포에 영향을 줄 수 있을 것으로 생각된다.

• Archives of Pharmacal Research
• /
• 제20권3호
• /
• pp.275-279
• /
• 1997

Helicobacter pylori (H. pylorl) infection is now established as the major pathogenic factor in chronic gastritis and peptic ulcer disease. in addition, there is accumulating evidence that H. pylori plays an important role in the process of gastric carcinogenesis. On the other hand, oriental traditional medicines have been used for stomach disease for thousands of years. In the present study, methanol extract from the stem bark of Magnolia sieboldii (M. sieboldii) and its components were investigated on their inhibitory effects against urease activity and growth of H. pylori in vitro. The methanol extract of M. sieboldii significantly inhibited the growth of H. pylori ATCC 43504 at 5 mg/ml. From the further fractionation, the chloroform fraction inhibited the bacterial growth dose-dependently. Among four fractions separated from the chloroform fraction by silica gel column chromatography, MS-C-2 was the most potent. Costunolide was isolated from the MS-C-2 subtraction by preparative TLC and recrystallization using n-hexane. Anti-H. pylori effect of costunolide was investigated using one commercial strain (H. pylori ATCC 43504) and three clinical strains (H. pylon 4, 43, 82548). Costunolide exhibited potent anti-H. pylori activity, and the MIC was around $100-200{\mu}g/ml$. However, costunolide had no inhibitory effect of H. pylori urease activity at the concentration used for the growth inhibition assay. From these results, we conclude that costunolide inhibits the, growth of H. pylori by the independent manner of H. pylori urease inhibition.

• 생약학회지
• /
• 제35권3호통권138호
• /
• pp.250-254
• /
• 2004

Helicobacter pylori (H. pyroli) infection it associated with type B gastritis, peptic uler disease, and gastric cancer. The vacuolation of cells induced by H. pylori is thought to be essential for the initiation and maintenance of gastric infection. The roles of H. pylori cytotoxin, urease, and ammonia in the vacuolation of HeLa cells were determined. H. pylori toxin induced vacuolation of HeLa cells. Korean and Japanese radishes significantly prevented the vacuolation of HeLa cells induced by H. pylori toxin. The urease activity in vacuolated cells was also decreased with Korean and Japanese radishes. H. Pylori toxin-induced vacuolation was inhibited by vacuolar type ATPase inhibitors (bafilomycin and N-ethylmaleimide). However, further investigation is required to determine the mechanisms of radish for the inhibition of vacuole formation of eukaryotic cells in response to the H. pylori toxin.