***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background : Helicobacter pylori eradication rates achieved with a first-line regimen of clarithromycin ( CLR ) combined with amoxicillin ( AMX ) and a proton pump inhibitor have recently fallen to ⩽80 % because of the increasing incidence of CLR resistance in Japan . This r and omized multicenter trial aim ed to compare the eradication success of 2 first-line triple therapy regimens : rabeprazole , amoxicillin , and clarithromycin ( RAC ) versus rabeprazole , amoxicillin , and metronidazole ( RAM ) . Methods : A total of 124 consecutive patients infected with H. pylori were r and omized into one of two 7-day therapeutic regimens : RAC ( n=60 ) or RAM ( n=64 ) . Eradication was confirmed by the 13C-urea breath test . Adverse effects were also assessed . Results : Intention-to-treat and per protocol H. pylori eradication rates were 73.3%/77.2 % in the RAC group and 90.6%/93.5 % in the RAM group . The eradication rate  of RAM therapy was significantly higher than that of RAC therapy . CLR , metronidazole , and AMX resistance was found in 36.2 % , 2.1 % , and 0 % of patients , respectively . In addition , no relevant differences in adverse effects were observed . Conclusions : Metronidazole-based therapy ( RAM ) was superior to st and ard CLR-based therapy ( RAC ) for first-line H. pylori eradication . This reflects the progressive increase in CLR resistance observed in Japan AIM To assess and compare the efficacy and safety of two triple regimes : A ) metronidazole , amoxicillin and omeprazole , which is still widely used in Russia , and B ) azithromycin , amoxicillin and omeprazole in healing active duodenal ulcer and H.pylori eradication . METHODS 100 patients with active duodenal ulcer were included in the open , multicentre , r and omized study with comparative groups . Patients were r and omly assigned to one of the following one-week triple regimes : A ) metronidazole 500 mg bid , amoxicillin 1 g bid and omeprazole 20 mg bid ( OAM , n=50 ) and B ) azithromycin 1 g od for the first 3 days ( total dose 3 g ) , amoxicillin 1 g bid and omeprazole 20 mg bid ( OAA , n=50 ) . Omeprazole 20 mg od was given after the eradication course as a monotherapy for three weeks . The control endoscopy was performed 8 weeks after the entry . H.pylori infection was determined in the entry of the study and four weeks after the cessation of treatment by means of histology and CLO-test . RESULTS 97 patients completed the study according to the protocol ( 1 patient of the OAM group did not come to the control endoscopy , 2 patients of the OAA group stopped the treatment because of mild allergic urticaria ) . Duodenal ulcers were healed in 48 patients of the OAM group ( 96 % ; CI 90.5 - 100 % ) and in 46 patients of the OAA group ( 92 % ; CI 89.5 - 94.5 % ) ( p = ns ) . H.pylori infection was eradicated in 15 out of 50 patients with OAM ( 30 % ; CI 17 - 43 % ) and in 36 out of 50 patients treated with OAA ( 72 % ; CI 59 - 85 % ) (P<0.001)- ITT analysis . CONCLUSION The triple therapy with omeprazole , amoxicillin and metronidazole failed to eradicate H.pylori in the majority of patients , which is an essential argument to withdraw this regimen out of the national recommendations . Macrolide with amoxicillin are preferable to achieve higher eradication rates .  Azithromycin ( 1 g od for the first 3 days ) can be considered as a successful component of the triple PPI-based regimen This study compared high dose ranitidine versus low dose omeprazole with antibiotics for the eradication of H pylori .  80 patients ( mean age 48 years , range 18 - 75 ) who had H pylori infection were r and omised in an investigator-blind manner to either a two-week regime of omeprazole 20 mg daily , amoxycillin 500 mg tid and metronidazole 400 mg tid ( OAM ) , or ranitidine 600 mg bd , amoxycillin 500 mg tid and metronidazole 400 mg tid ( RAM ) , or omeprazole 20 mg daily and clarithromycin 500 mg tid ( OC ) , or omeprazole 20 mg daily and placebo ( OP ) . H pylori was eradicated in 6 of 19 patients in the OAM group ( 32 % ) ; 8 of 18 in the RAM group ( 44 % ) , 4 of 15 in the OC group ( 27 % ) ; none of 18 in the OP group ( 0 % ) . [ < P0.005 for OAM , RAM , OC vs OP ; P = N.S. between OAM , RAM , OC ] . Overall metronidazole resistance was unexpectedly high at 58 % . Eradication rates in metronidazole sensitive patients were 71 % ( 5/7 ) and 100 % ( 3/3 ) for OAM and RAM respectively . In conclusion , H pylori eradication rates using high dose ranitidine plus amoxycillin and metronidazole may be similar to that of low dose omeprazole in combination with the same antibiotics for omeprazole with clarithromycin .  Overall eradication rates were low due to a high incidence of metronidazole resistance but were higher in metronidazole-sensitive patients . Even high dose ranitidine with two antibiotics achieves a relatively low eradication rate . These metronidazole-based regimens can not be recommended in areas with a high incidence of metronidazole resistance BACKGROUND & AIMS The currently recommended first-line eradication treatment of Helicobacter pylori in children is usually successful in about 75 % . Recently , in adults , a novel 10-day sequential treatment has achieved an eradication rate of 95 % . The aim of the study was to assess the H pylori eradication rate of the sequential treatment regimen compared with conventional triple therapy in children . METHODS Seventy-eight consecutive children with H pylori infection were r and omized to receive either sequential treatment ( omeprazole plus amoxicillin for 5 days , followed by omeprazole plus clarithromycin plus tinidazole for another 5 days ) ( n = 38 ; 15 boys [ 39.5 % ] ; median age , 11.0 years [ range , 3.3 - 16 years ] ) or triple therapy ( omeprazole , amoxicillin , and metronidazole ) for 1 week ( n = 37 ; 15 boys [ 40.5 % ] ; median age , 9.9 years [ range , 4.3 - 16 years ] ) . H pylori infection was based on 2 out of 3 positive tests results : 13C-urea breath test , rapid urease test , and histologic analysis . Eradication was assessed by 13C-urea breath test 8 weeks after therapy . RESULTS Seventy-four patients completed the study . H pylori eradication was achieved in 36 children receiving sequential treatment ( 97.3 % ; 95 % confidence interval , 86.2 - 99.5 ) and 28 children receiving triple therapy ( 75.7 % ; 95 % confidence interval , 59.8 - 86.7 ) ( P < .02 ) . Compliance with therapy was good ( > 95 % ) in all . CONCLUSIONS Our study shows , for the first time in children , that 10-day sequential treatment achieves a higher eradication rate than st and ard triple therapy , which is consistent with the results of adult studies ABSTRACT Culture and susceptibility testing of Helicobacter pylori strains was performed in a large multinational , multicenter r and omized clinical trial . Culture was carried out on gastric biopsy sample s obtained from 516 patients at entry and had a sensitivity of 99 % when the [13C]urea breath test was used as a reference . Susceptibility testing was performed for clarithromycin and metronidazole on 485 strains by an agar dilution method and the epsilometer test ( Etest ) and for amoxicillin by an agar dilution method only . Resistance to clarithromycin  ( > 1 μg/ml ) was found in 3 % of the H. pylori strains , with a perfect correlation between Etest and agar dilution methods . Resistance to metronidazole  ( > 8 μl/ml ) was found in 27 % of the strains by agar dilution , but there were important discrepancies between it and the Etest method . No resistance to amoxicillin was found . The logarithms of the MICs of the three antibiotics against susceptible strains had a distribution close to normal . The impact of resistance was tested in the four arms of the trial . There were not enough clarithromycin-resistant strains to evaluate the impact of resistance on the cure rate of clarithromycin-based regimens . For metronidazole-resistant strains , the impact noted in the clarithromycin-metronidazole arm was partially overcome when omeprazole was added ( 76 % eradication for resistant strains versus 95 % for susceptible strains ) . Secondary resistance to clarithromycin occurred in strains from 12 of 105 patients ( 11.4 % ) after the failure of a clarithromycin-based regimen to effect eradication . The detection of point mutations in clarithromycin-resistant strains was performed by a combination of PCR and restriction fragment length polymorphism . Mutations ( A2142 G and 2143 G ) were found in all strains tested except one . This study stresses the importance of performing susceptibility tests in clinical trials in order to explain the results of different treatments CONTEXT Although chronic Helicobacter pylori infection is associated with gastric cancer , the effect of H pylori treatment on prevention of gastric cancer development in chronic carriers is unknown . OBJECTIVE To determine whether treatment of H pylori infection reduces the incidence of gastric cancer . DESIGN , SETTING , AND PARTICIPANTS Prospect i ve , r and omized , placebo-controlled , population -based primary prevention study of 1630 healthy carriers of H pylori infection from Fujian Province , China , recruited in July 1994 and followed up until January 2002 . A total of 988 participants did not have precancerous lesions ( gastric atrophy , intestinal metaplasia , or gastric dysplasia ) on study entry . INTERVENTION Patients were r and omly assigned to receive H pylori eradication treatment : a 2-week course of omeprazole , 20 mg , a combination product of amoxicillin and clavulanate potassium , 750 mg , and metronidazole , 400 mg , all twice daily ( n = 817 ) ; or placebo ( n = 813 ) . MAIN OUTCOME MEASURES The primary outcome measure was incidence of gastric cancer during follow-up , compared between H pylori eradication and placebo groups . The secondary outcome measure was incidence of gastric cancer in patients with or without precancerous lesions , compared between the 2 groups . RESULTS Among the 18 new cases of gastric cancers that developed , no overall reduction was observed in participants who received H pylori eradication treatment ( n = 7 ) compared with those who did not ( n = 11 ) ( P = .33 ) . In a subgroup of patients with no precancerous lesions on presentation , no patient developed gastric cancer during a follow-up of 7.5 years after H pylori eradication treatment compared with those who received placebo ( 0 vs 6 ; P = .02 ) . Smoking ( hazard ratio [ HR ] , 6.2 ; 95 % confidence interval [ CI ] , 2.3 - 16.5 ; P<.001 ) and older age ( HR , 1.10 ; 95 % CI , 1.05 - 1.15 ; P<.001 ) were independent risk factors for the development of gastric cancer in this cohort . CONCLUSIONS We found that the incidence of gastric cancer development at the population level was similar between participants receiving H pylori eradication treatment and those receiving placebo during a period of 7.5 years in a high-risk region of China . In the subgroup of H pylori carriers without precancerous lesions , eradication of H pylori significantly decreased the development of gastric cancer . Further studies to investigate the role of H pylori eradication in participants with precancerous lesions are warranted BACKGROUND Helicobacter pylori eradication with omeprazole , amoxycillin , and metronidazole is both effective and inexpensive . However , eradication rates with different dosages and dosing vary , and data on the impact of resistance are sparse . In this study , three different dosages of omeprazole , amoxyc 
    Output:
    
PAM was less efficacious than clarithromycin-including triple therapies .
However , its efficacy was similar to that of PAC when drugs were administered for 14 days , although ITT cure rates did not reach 90 % .
Use of 14 day , thrice daily and high-metronidazole-dose PAM treatments markedly increased the cure rate