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Correlation between H. pylori genotype and alcohol dehydrogenase activity
A1280 AGA ABSTRACTS
5847 LOSS OF PLASMIDS FROM HELICOBACTER PYLORI UPON CONVERSION TO COCCOID FORM. Darren Morton. Karna D. Bardhan, Rotherham Gen Hosp, Rotherham , United Kingdom. INTRODUCTION In certain culture conditions the bacilliary morphology of fl. pylori (HP) modifies to a coccoid structure. This alteration may represent a step in the transmission of the infection, though has yet to be successfully recovered by culture . Earlier , we demonstrated a clear reduction in DNA-associated fluorescence upon coccoid transformation (Gastroenterology 1998:114;G0961). and an alteration in genus specific DNA melting point (Gut 1999:44;W34I ). We have now investigated if carriage of plasmids, found in helical HP strains, is affected during conversion to coccoid bacterial form. METHODS 100 consecutive HP strains, were isolated on solid media (bioMerieux Ltd. UK), for analysis in this study. Strains which initially demonstrated plasmids were further processed to produce parallel cultures aged 3, and 18 days old. Gram stain microscopy was used to confirm the morphology of the HP cells after the prolonged incubat ion period. Bacterial plasmid DNA was extracted from helical and coccoid parallel cultures using standard methods then visualised and sized after electrophoresis . RESULTS 36 (36%) of HP strains carried one or more plasmids. Plasmid sizes ranged from 1.45-7.8MDa. 13 (36%) strains carried a single plasmid; 9 (25%) carried 2 plasmids; 2 (6%)carried 3 plasmids; 10 (27%)carried 4 plasmid s and 2 (3%)strains carried 5 or 6 plasmid s each. Repeated culture showed plasmid carraige was stable however, after coccoid conversion no plasmids could be extracted from any plasmid bearing strain. CONCLUSIONS The range of plasmid sizes extracted from the strains under test was broad. though generally small. Upon cocco id conversion these HP strains appeared to lose all plasmid DNA. Although no function has been assigned to these plasmids, it is reasonable to assume that their loss may have a significant effect on bacterial strain survival. Loss of plasmid DNA during coccoid conversion appears to mirror the previously demonstrated loss of chromosomal DNA, suggestin§ the same mechanism of DNA loss may be responsible. Th " work was su p porte bv ,II f' Hardhan Research & Edu ca tio n Trus t ( BR ET)
5848 EPINEPHRINE INJECTION FOR ENDOSCOPIC HEMOSTASIS IN PATIENTS WITH BLEEDING PEPTIC ULCERS: A RETROSPECTIVE STUDY. Karim B. Muhammad , Amir Sherwani , Mark Welfare, Roger Barton, Irving Cobden, Seamus B. Kelly, North Tyneside Gen Hosp, Newcastle, United Kingdom. Aim: To determin e the outcome of endoscopic hemostasis using epinephrine injection in patients with bleeding peptic ulcers, in terms of: initial hemostasis, clinical rebleed, second injection, requirements for emergency surgery. blood transfusion, hospital stay and mortality. Background : Endoscopic hemosta sis is now a well established first line treatment for bleeding peptic ulcers, with surgical intervent ion being reserved for those who continue to bleed or rebleed . Epinephrine injection for endoscopic hemostasis has a success rate up to 98%. Simplicity, low cost and availability, with reduced risk of tissue injury and decreased incidence of recurrent bleeding make it an ideal choice for treatment. Methods: A retrospective study reviewed the results of epinephrine injection in 116 patients (M:F= 72:44) with actively bleeding peptic ulcers, admitted to a teaching hospital between 1994 and 1999. Endoscopy was performed within 24 hours in 86 patients (71.6 %). 38 patients (32.8%) were shocked on admission and were resuscitated prior to endoscopy . Results: Patients had a mean age of 69 years(range 22-77 years). Ninety three patients were aged ;,:,60 years and twenty five patients were aged ;,:,80 years. Seventy patients (60.4%) had severe systemic disease and 63 patients (54.3%) were laking aspirin or non-steroidal anti-inflammatory drugs or both. Thirty eight patients (32.8%) were shocked on admission. Endoscopy findings included: 6 spurters (5.2%), 27 oozing vessels (23.3%), 49 visible vessels (42.2%), 20 adherent clots (17.2%),9 flat pigmented spots (7.8%) and 2 clean based ulcers ( 1.7%). Initial endoscopic hemostasis was achieved in 109 patients (94%). Clinical rebleed ing occurred in 26 patients (22.4%). Fourteen patients (12.1%) required a second injection and twenty patients ( 17.2%) required surgery. Ninety nine patients (85.3%) required blood transfusion (mean 5.3 units). The mean hospital stay was 14 days. Twenty one patients (18.1%) died in hospital. The mean age of the patients who died was 78 years. Conclusion : The study confirms that epinephrine injection is highly effective in stoppin g actively bleeding peptic ulcers. Higher mortality, longer hospital stay and surgery could be attributed to old age and severe systemic disease in our series of patients.
GASTROENTEROLOGY Vol. 118 . No.4
nase (ADH), which converts alcohol to acetaldehyde, which could contribute to gastric cell injury, especially in alcoholic patients. The present study was undertaken to correlate ADH activity in different H. pylori strains with H. pylori cagA status, vacA subtype and bacterial cytotoxicity. Methods: Fresh H. pylori isolates from African American patients, endoscoped at Howard University Hospital, were cultured on trypticase soy agar with sheep's blood. Each isolate was subcultured once after selecting small colonies for further culture. DNA was isolated from subsequent cultures for PCR analysis for cagA status and vacA alleles. In addition, isolates were sonicated to obtain cytosolic protein, then centrifuged at lOO.OOOg at 4°C. The supernatant was then assayed for cytosolic ADH activity. Strains were exposed to AGS cells overnight then assayed for sublethal cytotoxicity by measuring release of LDH into the culture medium. Results: The vacA s I genotype was common in African Americans patients with upper G./. symptoms (90%). The vacA s2lm2 genotype was rare in African Americans patients at our institution ( 10%). The vacA s llm l genotype is most common in African American patients at our institution. H. pylori isolates displayed a wide range of ADH activity, with some strains showing no activity at all. Out of 18 strains tested for ADH activity, 12 were cagA-pos and showed a mean ADH activity of 163 Ulng protein as compared with 6 cagA-neg strains which showed an average activity of 146 U1ng protein. Also, there was no correlation between ADH activity and vacA alleles (s l ,s2,m l ,m2). There was a direct correlation between LDH release into culture medium and ADH activity. Conclusion: At our institution the predominant H. pylori genotype in African Americans is cagA-pos and vacA sl/ml, which differs from published reports in Vietnamese subjects (sllm2), Greeks (slim)) and Lebanese (s2/m2 and s2m)). These findings suggest that H. pylori ADH activity does not correlate with cagA status or vacA subtype. However. we do find a trend for increased cytotoxicity in strains with high ADH activity. ADH activity may well contribute to H. pylori cytotoxicity, however. additional studies are needed.
5850 INITIAL POTENCY OF LANSOPRAZOLE AND OMEPRAZOLE· MUPS ON PENTAGASTRIN·STIMULATED GASTRIC ACID SEe CRETION - A PLACEBO-CONTROLLED STUDY IN HEALTHY VOLUNTEERS. Peter Muller, Mehmet A. Goksu, Winfried Am Fuchs, Frank Schluter, Bernd Simon. Krankenhaus Salem, Heidelberg, Germany ; Takeda Pharma GmbH, Aachen , Germany; Kreiskrankenhau s, Schwetzingen, Germany. Aim: The purpose of this study was to compare the efficacy of different doses of lansoprazole and omeprazole-MUPS and to find equipotent dosages of the two proton pump inhibitors. Method s: 12 Hp-negative male subjects entered this placebo-controll ed, six-way cross-over study. During the dosing periods of two days duration, one of the following treatments was administered: 10 mg or 20 mg omeprazole-MUPS, or 7.5 mg or 15 mg or 30 mg lansoprazole , or placebo. The wash-out period between each phase was one week. The treatment order was randomised . Pentagastrinstimulated gastric acid secretion was determined by means of aspiration of the stomach contents in 15-min intervals between 12.5 and 14.5 hours after dosing. The aspirated volume was titrated, the volume and the pH were documented . Acid output was calculated in mmoll15 min and expressed as a percentage of the placebo values. Results: Mean relative gastric acid secretion is shown in the table as mean :t standard deviation. The twosided 95% confidence interval for the mean is given in square brackets. Conclusion: Lansoprazole 15 mg and omeprazole-MUPS 20 mg have about the same potency to suppress pentagastrin-stimulated secretion of gastric acid on the first two days. The potency of lansoprazole 30 mg is higher than that of lansoprazoJe 15 mg and omeprazole-MUPS 20 mg. Neither the effect of lansoprazole 7.5 mg. nor that of omeprazole-MUPS 10 mg, is clearly different from placebo on the first two days. The interindividual variation of acid suppression is considerably higher after omeprazole than after lansoprazole . The effect of lansoprazole is already pronounced on the first day, whereas the effect of omeprazole -MUPS is significantly different from placebo only on the second day. Mean relative (% ofpacebo) gastricacidsecretion rate. ITT analysis. Drug Lansoprazole 7.Smg Lansoprazole 15mg Lansoprazole 30mg Omeprazole-MUPS 10mg Omeprazole-MUPS 20mg
Day 1
Day 2
109 ± 38[84; 133] 75 ± 37[52; 991 48± 35[26: 7O] 92± 49 [61; 123) 78 ± 49(47: 109]
102 ± 43[75; 1301 62 ± 37[38; 85] 37± 22[23; 50] 93± 55[58; 128) 56+ 48[24; 89]
5849
5851
CORRELATION BETWEEN H. PYLORI GENOTYPE AND ALCOHOL DEHYDROGENASE ACTIVITY. Ranadev Mukherjee, Nasar Sabra, Amel Ahmed, Sai L. Chandaran, Anm Rahman , Mitra Tavakolli, Cornell R. Allen. Hassan Ashktorab, Duane T. Smoot. Howard Univ, Washington, DC. Background: H. pylori is a gram negative bacterium which has been associated with chronic gastritis and peptic ulcer disease. Many virulence associated genes have been identified for H. pylori , including cagA, vacA, and iceA . However, it remains unclear how much they contribute to H. pylori induced cell injury. H. pylori also possesses an alcohol dehydroge-
A COMPARISON OF THE ALKALINE REFLUX CHARACTERISITCS OF OESOPHAGITIS AND BARRETT'S OESOPHAGUS. Frank R. Murphy. Dominic Foy, Christopher Sheen, Alan Macfarlane, Paul J. Winwood, Royal Bournemouth Hosp, Bournemouth, United Kingdom . It is generally accepted that Barrett ' s oesophagus is an acquired condition caused by chronic reflux of gastric, duodenal contents or both. Adenocarcinomas complicating Barrett 's oesophagus usually have adjacent areas of epithelium that show dysplasia . The trophic agent that promotes dyspla stic change is unknown. Aim: To determine the amount of alkaline exposure in
5847 LOSS OF PLASMIDS FROM HELICOBACTER PYLORI UPON CONVERSION TO COCCOID FORM. Darren Morton. Karna D. Bardhan, Rotherham Gen Hosp, Rotherham , United Kingdom. INTRODUCTION In certain culture conditions the bacilliary morphology of fl. pylori (HP) modifies to a coccoid structure. This alteration may represent a step in the transmission of the infection, though has yet to be successfully recovered by culture . Earlier , we demonstrated a clear reduction in DNA-associated fluorescence upon coccoid transformation (Gastroenterology 1998:114;G0961). and an alteration in genus specific DNA melting point (Gut 1999:44;W34I ). We have now investigated if carriage of plasmids, found in helical HP strains, is affected during conversion to coccoid bacterial form. METHODS 100 consecutive HP strains, were isolated on solid media (bioMerieux Ltd. UK), for analysis in this study. Strains which initially demonstrated plasmids were further processed to produce parallel cultures aged 3, and 18 days old. Gram stain microscopy was used to confirm the morphology of the HP cells after the prolonged incubat ion period. Bacterial plasmid DNA was extracted from helical and coccoid parallel cultures using standard methods then visualised and sized after electrophoresis . RESULTS 36 (36%) of HP strains carried one or more plasmids. Plasmid sizes ranged from 1.45-7.8MDa. 13 (36%) strains carried a single plasmid; 9 (25%) carried 2 plasmids; 2 (6%)carried 3 plasmids; 10 (27%)carried 4 plasmid s and 2 (3%)strains carried 5 or 6 plasmid s each. Repeated culture showed plasmid carraige was stable however, after coccoid conversion no plasmids could be extracted from any plasmid bearing strain. CONCLUSIONS The range of plasmid sizes extracted from the strains under test was broad. though generally small. Upon cocco id conversion these HP strains appeared to lose all plasmid DNA. Although no function has been assigned to these plasmids, it is reasonable to assume that their loss may have a significant effect on bacterial strain survival. Loss of plasmid DNA during coccoid conversion appears to mirror the previously demonstrated loss of chromosomal DNA, suggestin§ the same mechanism of DNA loss may be responsible. Th " work was su p porte bv ,II f' Hardhan Research & Edu ca tio n Trus t ( BR ET)
5848 EPINEPHRINE INJECTION FOR ENDOSCOPIC HEMOSTASIS IN PATIENTS WITH BLEEDING PEPTIC ULCERS: A RETROSPECTIVE STUDY. Karim B. Muhammad , Amir Sherwani , Mark Welfare, Roger Barton, Irving Cobden, Seamus B. Kelly, North Tyneside Gen Hosp, Newcastle, United Kingdom. Aim: To determin e the outcome of endoscopic hemostasis using epinephrine injection in patients with bleeding peptic ulcers, in terms of: initial hemostasis, clinical rebleed, second injection, requirements for emergency surgery. blood transfusion, hospital stay and mortality. Background : Endoscopic hemosta sis is now a well established first line treatment for bleeding peptic ulcers, with surgical intervent ion being reserved for those who continue to bleed or rebleed . Epinephrine injection for endoscopic hemostasis has a success rate up to 98%. Simplicity, low cost and availability, with reduced risk of tissue injury and decreased incidence of recurrent bleeding make it an ideal choice for treatment. Methods: A retrospective study reviewed the results of epinephrine injection in 116 patients (M:F= 72:44) with actively bleeding peptic ulcers, admitted to a teaching hospital between 1994 and 1999. Endoscopy was performed within 24 hours in 86 patients (71.6 %). 38 patients (32.8%) were shocked on admission and were resuscitated prior to endoscopy . Results: Patients had a mean age of 69 years(range 22-77 years). Ninety three patients were aged ;,:,60 years and twenty five patients were aged ;,:,80 years. Seventy patients (60.4%) had severe systemic disease and 63 patients (54.3%) were laking aspirin or non-steroidal anti-inflammatory drugs or both. Thirty eight patients (32.8%) were shocked on admission. Endoscopy findings included: 6 spurters (5.2%), 27 oozing vessels (23.3%), 49 visible vessels (42.2%), 20 adherent clots (17.2%),9 flat pigmented spots (7.8%) and 2 clean based ulcers ( 1.7%). Initial endoscopic hemostasis was achieved in 109 patients (94%). Clinical rebleed ing occurred in 26 patients (22.4%). Fourteen patients (12.1%) required a second injection and twenty patients ( 17.2%) required surgery. Ninety nine patients (85.3%) required blood transfusion (mean 5.3 units). The mean hospital stay was 14 days. Twenty one patients (18.1%) died in hospital. The mean age of the patients who died was 78 years. Conclusion : The study confirms that epinephrine injection is highly effective in stoppin g actively bleeding peptic ulcers. Higher mortality, longer hospital stay and surgery could be attributed to old age and severe systemic disease in our series of patients.
GASTROENTEROLOGY Vol. 118 . No.4
nase (ADH), which converts alcohol to acetaldehyde, which could contribute to gastric cell injury, especially in alcoholic patients. The present study was undertaken to correlate ADH activity in different H. pylori strains with H. pylori cagA status, vacA subtype and bacterial cytotoxicity. Methods: Fresh H. pylori isolates from African American patients, endoscoped at Howard University Hospital, were cultured on trypticase soy agar with sheep's blood. Each isolate was subcultured once after selecting small colonies for further culture. DNA was isolated from subsequent cultures for PCR analysis for cagA status and vacA alleles. In addition, isolates were sonicated to obtain cytosolic protein, then centrifuged at lOO.OOOg at 4°C. The supernatant was then assayed for cytosolic ADH activity. Strains were exposed to AGS cells overnight then assayed for sublethal cytotoxicity by measuring release of LDH into the culture medium. Results: The vacA s I genotype was common in African Americans patients with upper G./. symptoms (90%). The vacA s2lm2 genotype was rare in African Americans patients at our institution ( 10%). The vacA s llm l genotype is most common in African American patients at our institution. H. pylori isolates displayed a wide range of ADH activity, with some strains showing no activity at all. Out of 18 strains tested for ADH activity, 12 were cagA-pos and showed a mean ADH activity of 163 Ulng protein as compared with 6 cagA-neg strains which showed an average activity of 146 U1ng protein. Also, there was no correlation between ADH activity and vacA alleles (s l ,s2,m l ,m2). There was a direct correlation between LDH release into culture medium and ADH activity. Conclusion: At our institution the predominant H. pylori genotype in African Americans is cagA-pos and vacA sl/ml, which differs from published reports in Vietnamese subjects (sllm2), Greeks (slim)) and Lebanese (s2/m2 and s2m)). These findings suggest that H. pylori ADH activity does not correlate with cagA status or vacA subtype. However. we do find a trend for increased cytotoxicity in strains with high ADH activity. ADH activity may well contribute to H. pylori cytotoxicity, however. additional studies are needed.
5850 INITIAL POTENCY OF LANSOPRAZOLE AND OMEPRAZOLE· MUPS ON PENTAGASTRIN·STIMULATED GASTRIC ACID SEe CRETION - A PLACEBO-CONTROLLED STUDY IN HEALTHY VOLUNTEERS. Peter Muller, Mehmet A. Goksu, Winfried Am Fuchs, Frank Schluter, Bernd Simon. Krankenhaus Salem, Heidelberg, Germany ; Takeda Pharma GmbH, Aachen , Germany; Kreiskrankenhau s, Schwetzingen, Germany. Aim: The purpose of this study was to compare the efficacy of different doses of lansoprazole and omeprazole-MUPS and to find equipotent dosages of the two proton pump inhibitors. Method s: 12 Hp-negative male subjects entered this placebo-controll ed, six-way cross-over study. During the dosing periods of two days duration, one of the following treatments was administered: 10 mg or 20 mg omeprazole-MUPS, or 7.5 mg or 15 mg or 30 mg lansoprazole , or placebo. The wash-out period between each phase was one week. The treatment order was randomised . Pentagastrinstimulated gastric acid secretion was determined by means of aspiration of the stomach contents in 15-min intervals between 12.5 and 14.5 hours after dosing. The aspirated volume was titrated, the volume and the pH were documented . Acid output was calculated in mmoll15 min and expressed as a percentage of the placebo values. Results: Mean relative gastric acid secretion is shown in the table as mean :t standard deviation. The twosided 95% confidence interval for the mean is given in square brackets. Conclusion: Lansoprazole 15 mg and omeprazole-MUPS 20 mg have about the same potency to suppress pentagastrin-stimulated secretion of gastric acid on the first two days. The potency of lansoprazole 30 mg is higher than that of lansoprazoJe 15 mg and omeprazole-MUPS 20 mg. Neither the effect of lansoprazole 7.5 mg. nor that of omeprazole-MUPS 10 mg, is clearly different from placebo on the first two days. The interindividual variation of acid suppression is considerably higher after omeprazole than after lansoprazole . The effect of lansoprazole is already pronounced on the first day, whereas the effect of omeprazole -MUPS is significantly different from placebo only on the second day. Mean relative (% ofpacebo) gastricacidsecretion rate. ITT analysis. Drug Lansoprazole 7.Smg Lansoprazole 15mg Lansoprazole 30mg Omeprazole-MUPS 10mg Omeprazole-MUPS 20mg
Day 1
Day 2
109 ± 38[84; 133] 75 ± 37[52; 991 48± 35[26: 7O] 92± 49 [61; 123) 78 ± 49(47: 109]
102 ± 43[75; 1301 62 ± 37[38; 85] 37± 22[23; 50] 93± 55[58; 128) 56+ 48[24; 89]
5849
5851
CORRELATION BETWEEN H. PYLORI GENOTYPE AND ALCOHOL DEHYDROGENASE ACTIVITY. Ranadev Mukherjee, Nasar Sabra, Amel Ahmed, Sai L. Chandaran, Anm Rahman , Mitra Tavakolli, Cornell R. Allen. Hassan Ashktorab, Duane T. Smoot. Howard Univ, Washington, DC. Background: H. pylori is a gram negative bacterium which has been associated with chronic gastritis and peptic ulcer disease. Many virulence associated genes have been identified for H. pylori , including cagA, vacA, and iceA . However, it remains unclear how much they contribute to H. pylori induced cell injury. H. pylori also possesses an alcohol dehydroge-
A COMPARISON OF THE ALKALINE REFLUX CHARACTERISITCS OF OESOPHAGITIS AND BARRETT'S OESOPHAGUS. Frank R. Murphy. Dominic Foy, Christopher Sheen, Alan Macfarlane, Paul J. Winwood, Royal Bournemouth Hosp, Bournemouth, United Kingdom . It is generally accepted that Barrett ' s oesophagus is an acquired condition caused by chronic reflux of gastric, duodenal contents or both. Adenocarcinomas complicating Barrett 's oesophagus usually have adjacent areas of epithelium that show dysplasia . The trophic agent that promotes dyspla stic change is unknown. Aim: To determine the amount of alkaline exposure in