bluuebunny/crossref_metadata_2025_split huggingface dataset:
Maintaining diversity through intermediate disturbances: evidence from rodents colonizing rehabilitating coastal dunes
Authors: Ferreira S. M. , Van Aarde R. J. 
Published: March 2003

AbstractRodents inhabit the coastal dune forests of KwaZulu‐Natal, South Africa. Here habitat rehabilitation following mining of dunes has resulted in coastal dune forest succession similar to that recorded in nonmined forests. We investigated the colonization of rehabilitating stands and evaluate the role of disturbance in maintaining rodent diversity. A trapping programme was established between July 1993 and February 1995 during which rodent colonization, local extinction and species richness were recorded for rehabilitating stands of different ages. Trends in these variables were closely associated with one of three possible outcomes for a disturbed patch over time, with no intervening disturbances following the initial disturbance. Colonization was initially high which led to an increase in species richness. Extinction was lower than colonization, but became higher when the habitat was 3 years old, which led to a decline in richness. We extrapolate this result assuming negligibly small disturbances after the initiation of rehabilitation and suggest that intermediate levels of disturbance maintain rodent species richness in coastal dune forests. Furthermore, our results illustrated species turnover, a prediction of the recorded outcome, with young stands dominated by Mastomys natalensis and older stands by Saccostomus campestris or Aethomys chrysophilus.
Spatial and temporal patterns in Lemniscomys striatus (Linnaeus 1758) as revealed by radio‐tracking
Authors: Hoffmann Anke , Klingel Hans 
Published: March 2003

Abstract Lemniscomys striatus was radio‐tracked in the Imperata‐Cymbopogon grassland of the Queen Elizabeth National Park in Uganda. Home range sizes calculated by Ranges V® using the minimum convex Polygon method (at 95%) in the postburnt grassland were on average 4.8 times larger than those before the fire. An inverse relation between home range size and population density was found. Lemniscomys striatus was diurnal with two activity peaks during daylight, but activity ended only after dusk.
The ecological changes of Echuya afromontane bamboo forest, Uganda
Authors: Banana A. Y. , Tweheyo M. 
Published: March 2003

AbstractEchuya forest reserve was gazetted in 1939 and was then mainly a bamboo forest with very few hardwood trees. However, the current ecological situation shows that hardwood trees are replacing bamboo. This study analysed the current ecological situation in relationship to past ecological changes and influences. Line transects were laid systematically at 1000 m intervals across the forest in order to describe the current vegetation variation.Echuya forest has changed in size and composition from 1954 to the present. The area occupied by pure bamboo has decreased from 20.5% to 12.5%, bamboo–hard wood mixture decreased from 48.2% to 26.2% and pure hardwood stands increased from 16% to 51%. It can be suggested that the exclusion of fire, herbivores and human activities after reservation of Echuya have gradually led to the conversion of the grassland–bamboo ecosystem into a hardwood forest ecosystem. Macaranga kilimandscharia Pax. is the major colonizing hardwood tree species. Most of the gaps are covered with heavy loads of Mimulopsis species climbers, which suppress bamboo growth.
The problem of precision and trend detection posed by small elephant populations in West Africa
Authors: Barnes R. F. W. 
Published: March 2003

AbstractThe precision of elephant estimates from aerial sample surveys and dung counts is inversely proportional to abundance. West African elephant populations are already small, and the power of a monitoring programme to detect changes in abundance diminishes as the population shrinks in size. Thus it will be difficult to evaluate the effects on elephant numbers of new management policies in West Africa. The same will be true of monitoring schemes for antelope and primate populations that are hunted for bushmeat. Elephant estimates from dung counts are more precise than those from aerial sample surveys, and changes in elephant numbers are more likely to be detected in the subregion by dung counts than by aerial sample surveys.
Two‐day ‘weekend’ lansoprazole‐quadruple therapy for Helicobacter pylori infection
Authors: Boer W. A. De , Etten R. J. X. M. Van , Coremans  , Schneeberger  
Published: March 2003

Background:The very high cure rate of 1‐week quadruple therapy offers an opportunity to study a shorter treatment duration. This is needed to construct a time–response curve for the regimen.Methods:Fifty‐two patients with endoscopically proven H. pylori infection received lansoprazole 30 mg b.d., tripotassium dicitrato bismuthate 120 mg q.d.s., tetracycline 500 mg q.d.s. and metronidazole 500 mg q.d.s., following 3 days of lansoprazole pre‐treatment. A second endoscopy was performed at least 6 weeks later. A patient was cured if histology, CLO‐test, and culture of antrum and corpus were negative.Results:We achieved an intention‐to‐treat cure rate of 30/50 (60%, 95% CI: 46–73%) and a per protocol cure rate of 30/48 (63%, 95% CI: 48–75%). Cure rate in metronidazole‐sensitive strains was 24/37 (65%, 95% CI: 48–79%) and 2/5 (40%) in resistant strains. All patients that failed the regimen had a metronidazole‐resistant strain post‐treatment. Compliance was excellent and moderate or severe side‐effects occurred in only 4% of patients.Conclusion:A 2‐day ‘weekend’ quadruple therapy cures only 60% of patients and cannot be recommended, but these findings provide an insight into the mode of action of quadruple therapy.
Omeprazole is more effective than cimetidine in the prevention of recurrence of GERD‐associated heartburn and the occurrence of underlying oesophagitis
Authors: Bate  , Green  , Axon  , Tildesley  , Murray  , Owen  , Emmas  , Taylor  
Published: March 2003

Background:There is documentation of the long‐term use of omeprazole 10 mg o.d. in patients with reflux oesophagitis but not in the large number of gastro‐oesophageal reflux disease (GERD) patients without oesophagitis. There is also a paucity of data on the long‐term use of cimetidine in GERD patients.Methods:One hundred and fifty‐six patients (100 male) who previously had symptomatic non‐ulcerative oesophagitis (81%) or symptoms without oesophagitis (19%), were recruited. All patients were in symptomatic remission following 4 weeks of omeprazole 20 mg o.d. or cimetidine 400 mg q.d.s. and, if required, a further 4 weeks of omeprazole 20 mg o.d. Patients were randomized to receive, double‐blind, either omeprazole 10 mg o.m. (n = 77) or cimetidine 800 mg nocte (n = 79) for 24 weeks.Results:A greater proportion of patients receiving omeprazole, compared with cimetidine, were in symptomatic remission after 12 (69 vs. 27%) and 24 weeks (60 vs. 24%) (each P < 0.0001). The median time to symptomatic relapse was longer for patients receiving omeprazole (169 vs. 15 days) (P = 0.0001). Of patients leaving the study in symptomatic remission, a greater proportion receiving omeprazole, compared with cimetidine, was free of oesophagitis (84 vs. 53%) (P < 0.05).Conclusion:Omeprazole 10 mg o.m. is more effective than cimetidine 800 mg nocte in the prevention of recurrence of GERD‐associated heartburn and the occurrence of underlying oesophagitis.
Effect of potassium‐magnesium citrate on upper gastrointestinal mucosa
Authors: Gonzalez  , Pak  , Adams‐Huet  , Taylor  , Bilhartz  
Published: March 2003

Background:Potassium supplements may cause mucosal damage of the gastrointestinal tract.Aim:To evaluate the effect of a new potassium supplement, potassium‐magnesium citrate (K‐Mag), on upper gastrointestinal mucosa and to compare it with an older potassium supplement, potassium citrate (Urocit‐K).Methods:A randomized and double‐blind study was conducted utilizing 36 healthy adults. Subjects were randomized into three groups: K‐Mag (70 mmol/day K, 35 mmol/day citrate and 17.6 mmol/day Mg); Urocit‐K (70 mmol/day K and 23.4 mmol/day citrate), and placebo. All subjects took 5 tablets b.d. of the allocated drug and 2 mg t.d.s. of glycopyrrolate for 7 days. On day 8, stool was examined for occult blood, a symptom score was calculated and an oesophagogastroduo‐denoscopy was performed. Mucosal lesions were scored at five anatomic sites.Results:Demographic characteristics and symptom score were similar in the three groups (< 10% with more than mild symptoms). There were no significant differences in the endoscopic scores at any site examined nor in the total scores among the three groups. Erosion or ulcers were found in 18% of K‐Mag, 23% of Urocit‐K and 17% of the placebo group.Conclusion:Short‐term use of K‐Mag does not appear to induce lesions in the upper gastrointestinal mucosa and its oral tolerance is similar to Urocit‐K or placebo.
The effects of low doses of ranitidine on intragastric acidity in healthy men
Authors: Wyeth  , Pounder  , Sercombe  , Snell  
Published: March 2003

Background:H2‐receptor antagonists are becoming widely available as over‐the‐counter medications for the treatment of heartburn and excess gastric acidity.Aim:To determine the effects of single low doses of ranitidine on intragastric acidity.Methods:Intragastric pH was measured for 9 h after lunch in five studies involving 24 healthy male volunteers. Antacid was given to all subjects on day 1. They then received single oral doses of a study drug 45 min after lunch on four separate occasions: placebo and either ranitidine 25 mg, 75 mg or 125 mg were given double‐blind according to a predetermined randomization schedule.Results:During both of the post‐dosing time periods (0–5 h and 5–9 h) there were significant decreases in integrated intragastric acidity for each ranitidine dose compared with placebo (P < 0.0001). There was a significant linear relationship between dose and integrated intragastric acidity with a greater decrease in acidity with increasing ranitidine doses (P < 0.0001). Compared with placebo, time with pH > 3 was significantly greater for ranitidine 75 mg and 125 mg (P < 0.001), but not ranitidine 25 mg. Results with the antacid were similar to placebo.Conclusions:Using low doses of ranitidine (25, 75 or 125 mg) there was a dose‐related decrease in intragastric acidity for 9 h after dosing. A single dose of antacid did not decrease intragastric acidity significantly.
Changes in Helicobacter pylori‐induced gastritis in the antrum and corpus during 12 months of treatment with omeprazole and lansoprazole in patients with gastro‐oesophageal reflux disease
Authors: Stolte  , Meining  , Schmitz  , Alexandridis  , Seifert  
Published: March 2003

Background:Several studies have shown that treatment with omeprazole leads to aggravation of Helicobacter pylori gastritis in the corpus. Whether this also applies to lansoprazole, and whether, in comparison with omeprazole, there are differences in therapy‐induced gastritis parameter changes remains unclear.Methods:In 111 patients infected with H. pylori and with gastro‐oesophageal reflux disease we investigated the gastritis parameters in antral and corpus mucosa before and after 2, 6 and 12 months of treatment with 15 or 30 mg lansoprazole or 20 mg omeprazole/day.Results:In all groups the different treatments had a similar effect: in both regions of the stomach, suppression or partial elimination of H. pylori was seen. However, improvement in the inflammation was observed only in the antrum, while in the corpus most gastritis parameters worsened significantly. There was no increase in intestinal metaplasia or atrophy.Conclusion:In common with omeprazole, lansoprazole aggravates the gastritis parameters in the corpus but improves them in the antrum. Treatment with proton pump inhibitors does not result in any increase in the incidence of atrophy/intestinal metaplasia. However, as gastritis predominating in the corpus seems to be associated with an elevated carcinogenic risk, consideration should be given to prophylactic H. pylori eradication therapy before initiating proton pump inhibitor treatment.
Peptic ulcer therapy with cimetidine versus tripotassium dicitrato bismuthate in rheumatoid arthritis patients undergoing chronic NSAID treatment
Authors: Porro G. Bianchi , Lazzaroni  , Petrillo  , Ardizzone  , Manzionna  , Caruso  , Montrone  
Published: March 2003

Aim:To compare the efficacy of cimetidine and tripotassium dicitrato bismuthate (TDB) in arthritic patients who had developed gastric (GU) or duodenal (DU) ulceration while taking non‐steroidal anti‐inflammatory drugs (NSAIDs).Methods:Eighty‐six rheumatoid arthritis (RA) patients affected by endoscopically proven DU (n = 44) or GU (n = 42), and on chronic NSAID therapy which was not suspended during anti‐ulcer therapy, were randomized to cimetidine (400 mg t.d.s.) or TDB (120 mg q.d.s.). A repeat endoscopy was planned after 4 weeks (and 8 weeks, in case of failed healing). The patients who were unhealed after 8 weeks of therapy were allocated to the alternative anti‐ulcer drug for a further 8 weeks without interrupting the anti‐inflammatory therapy.Results:At week 4 of therapy, 14/24 (58%) DU and 9/20 (45%) GU patients treated with cimetidine were healed, compared with 12/20 (60%) and 10/22 (45%) TDB‐treated patients (N.S.). At week 8 of therapy, the DU healing rates were 15/24 (63%) with cimetidine and 14/20 (70%) for TDB. The corresponding GU healing rates were 12/20 (60%) with cimetidine and 13/22 (60%) for TDB (N.S.). At week 16, complete healing with cimetidine was observed in 67% of DU and 57% of GU patients unhealed with TDB; the corresponding figures in the patients crossed to TDB were 83% for DU and 63% for GU patients (N.S. vs. cimetidine).Conclusions:No statistically significant difference was found between the healing activities of cimetidine and TDB in rheumatoid arthritis patients with peptic ulcer who did not interrupt their NSAID treatment for arthritis. This trial showed that the continued consumption of NSAIDs appears to slow the ulcer healing process, especially in GU patients.
Increased bone resorption in patients with Crohn’s disease
Authors: Robinson  , Iqbal  , Abrams  , Al‐Azzawi  , Mayberry  
Published: March 2003

Background:Patients with Crohn’s disease are at risk of osteoporosis and premature fracture. However, the pathophysiology underlying bone loss remains poorly understood and the optimum treatment has not been established.Aim:To investigate mechanisms of bone loss in Crohn’s disease using biochemical markers of bone turnover.Methods:Bone mineral density was measured at the hip and spine using dual‐energy X‐ray absorptiometry in 117 patients (48 male) with Crohn’s disease. Bone turnover was assessed by measuring serum osteocalcin (BGP), pro‐collagen carboxy‐terminal propeptide (PICP), bone specific alkaline phosphatase (BALP) and urinary deoxypyridinoline (DPD); and compared to age‐matched healthy controls (n = 28).Results:Bone mineral density was reduced (z‐score < −1) in 48 (41%) patients with Crohn’s disease. Mean values for bone formation markers in patients with Crohn’s disease were all within the normal reference range (BGP 8.92 (± 3.23) ng/mL (normal range 3.4–10.0), BALP 17.6 (± 12.6) U/L (normal range 11.6–43.3), PICP 95.1 (± 46.5) ng/mL (normal range 69–163)) and were not significantly different to the control population. However, mean urinary DPD was significantly higher in patients with Crohn’s disease compared to healthy controls (10.97 (± 9.22) n
M DPD/m
M creatinine vs. 5.02 (± 1.03) n
M DPD/m
M creatinine, difference in means = 5.95, 95% CI: −9.6 to −2.3, P = 0.00001) and compared to the UK reference range DPD levels were increased in 74 (63%) patients.Conclusions:Bone resorption as evidenced by urinary DPD was frequently increased in patients with Crohn’s disease and was significantly higher than in an age‐matched control population. The high levels of urinary DPD suggest increased bone collagen degradation may contribute to osteoporosis in patients with Crohn’s disease. These results suggest anti‐resorptive agents such as the bisphosphonates may be effective treatment for osteoporosis in Crohn’s disease.
Effect of alosetron on responses to colonic distension in patients with irritable bowel syndrome
Authors: Delvaux M. , Louvel D. , Mamet J.‐P. , Campos‐Oriola R. , Frexinos J. 
Published: March 2003

Background:Visceral hypersensitivity plays a major role in the pathophysiology of irritable bowel syndrome, as shown by balloon distension studies. 5‐HT3 receptors on afferent nerves may modulate visceral sensitivity and be the target of new treatments for irritable bowel syndrome.Aim:To evaluate the effects of alosetron, a potent and selective 5‐HT3 antagonist, on the perception of colonic distension by patients with irritable bowel syndrome, and on the colonic compliance to distension with a barostat.Methods:Twenty‐five irritable bowel syndrome patients were included in a randomized double‐blind parallel group trial; data were available for 22 (Rome criteria; 48 ± 11 years; 13 men and nine women). Patients were treated for 7 days with placebo (n = 6), alosetron 0.25 mg b.d. (n = 8) or alosetron 4 mg b.d. (n = 8). On day 6, a barostat bag was placed in the left colon. On day 7, after an overnight fast, isobaric phasic distensions were performed (4 mmHg steps, 5 min) up to the step triggering a sensation of abdominal pain.Results:Groups were comparable at inclusion (age, sex, symptoms, bowel habits). There were no differences between treatment groups in pressure recorded within the bag at the time of first sensation of abdominal pain. However, bag volumes were significantly increased. At the first sensation threshold, median volume differences of 61 mL and 90 mL (P = 0.028) were recorded with alosetron 0.25 mg b.d. and 4 mg b.d., respectively. At the threshold of abdominal pain, these differences were 71 mL (P = 0.039) and 84 mL (P = 0.017). Colonic compliance increased from 5.9 mL/mmHg on placebo to 7.6 mL/mmHg on alosetron 0.25 mg b.d. and to 9.8 mL/mmHg (P = 0.034) on alosetron 4 mg b.d.Conclusion:Alosetron increases the compliance of the colon to distension, and could thereby contribute to changes in perception of colonic distension and improvement in the symptoms of irritable bowel syndrome.
Reversal and protection against indomethacin‐induced blood stasis and mucosal damage in the rat jejunum by a β3‐adrenoceptor agonist
Authors: Kelly  , Piasecki  , Anthony  , Dhillon  , Pounder  , Wakefield  
Published: March 2003

Background:In the rat, indomethacin causes jejunal villous shortening, microvascular distortion, and blood stasis prior to ulceration. The β3‐adrenoceptor agonist CL316,243 (CL) prevents both the early histological changes and ulceration.Aim:To test the hypothesis that the β3‐adrenoceptor agonist CL316,243 exerts its protective effect by prevention and/or reversal of blood flow changes in the rat jejunum exposed to indomethacin.Methods:In anaesthetized rats, jejunal villous blood flow was measured in surface capillaries using fluorescence microscopy. Stasis of superficial capillary blood flow was induced by combined topical and i.v. indomethacin (100 μg/mL, 2.8 × 10−4 M). To examine the effect of CL on blood stasis, CL was applied either i.v. (1 mg/kg) or luminally (100 μg/mL, 2.5 × 10−5M) at the onset of stasis. Prophylactic protection was assessed by giving i.v. CL simultaneously with indomethacin. Results were compared with controls which received luminal saline applied at blood stasis. The effect of i.v. CL (1 mg/kg) alone, or luminal CL (100 μg/mL) alone on basal villous blood flow was also examined. The small intestines were perfusion‐fixed with 10% formol saline, and removed for histology, n = 5 for all groups.Results:Luminal CL given at stasis reversed indomethacin‐induced stasis within 10 min, whereas i.v. CL did not. Pretreatment with i.v. CL prevented the onset of stasis. Basal blood flow was raised slightly only by luminal CL.Conclusion:The β3‐adrenoceptor agonist CL316,243 can protect against indomethacin‐induced blood stasis in rat jejunal villi.
High Helicobacter pylori eradication rate with a 1‐week regimen containing ranitidine bismuth citrate
Authors: Gudjonsson  , Bardhan  , Hoie  , Kristensen  , Schuetz  , Kliebe‐Frisch  , Pipkin  , Duggan  
Published: March 2003

Background:High Helicobacter pylori eradication rates have consistently been reported with 2‐week dual therapy regimens of ranitidine bismuth citrate plus clarithromycin. Ranitidine bismuth citrate with two antibiotics may provide an alternative 1‐week eradication regimen.Methods:This double‐blind, randomized, parallel group, international, multicentre study compared ranitidine bismuth citrate 400 mg b.d. and clarithromycin 500 mg b.d. for 2 weeks (RC) with ranitidine bismuth citrate 400 mg b.d., clarithromycin 500 mg b.d. and metronidazole 400 mg b.d. for 1 week (RCM) for eradication of H. pylori in 350 patients with dyspepsia.Results:Treatment with RC and RCM eradicated H. pylori (established by the combination of two negative results from two discrete 13C‐UBTs at nominal weeks 4 and 12) from 89% (95% CI: 84–94) and 92% (95% CI: 88–97) of the observed population, and from 78% (95% CI: 72–84) and 80% (95% CI: 75–86) of the intention‐to‐treat population. When established only by one negative 13C‐UBT result at least 28 days after the end of treatment, the respective intention‐to‐treat rates were 85% (95% CI; 79–90) and 88% (95% CI: 83–93). Both regimens were well‐tolerated, only 6% of patients given RC and 4% given RCM discontinued treatment. Median plasma bismuth concentrations at the end of the second week of study were low, at 3.5 and 0.4 ng/mL, respectively.Conclusions:Ranitidine bismuth citrate triple therapy for 1 week (RCM) and dual therapy for 2 weeks (RC) were equally effective for the eradication of H. pylori infection.
Maintenance of remission of ulcerative colitis: a comparison between balsalazide 3 g daily and mesalazine 1.2 g daily over 12 months
Authors: Green  , Gibson  , Kerr  , Swarbrick  , Lobo  , Holdsworth  , Crowe  , Schofield  , Taylor  ,   THE ABACUS INVESTIGATOR GROUP
Published: March 2003

Background:Despite widespread use of aminosalicylates as maintenance treatment for ulcerative colitis (UC), patients still report troublesome symptoms, often nocturnally.Aim:To compare the efficacy and safety of balsalazide (Colazide) with mesalazine (Asacol) in maintaining UC remission.Methods:A randomized, double‐blind comparison of balsalazide 3 g daily (1.04 g 5‐ASA) and mesalazine 1.2 g daily for 12 months, in 99 (95 evaluable) patients in UC remission.Results:Balsalazide patients experienced more asymptomatic nights (90% vs. 77%, P = 0.0011) and days (58% vs. 50%, N.S.) during the first 3 months. Balsalazide patients experienced more symptom‐free nights per week (6.4 ± 1.7 vs. 4.7 ± 2.8; P = 0.0006) and fewer nights per week with blood on their stools or on the toilet paper, mucus with their stools or with sleep disturbance resulting from symptoms or lavatory visits (each P < 0.05). Fewer balsalazide patients relapsed within 3 months (10% vs. 28%; P = 0.0354). Remission at 12 months was 58% in both groups. Similar proportions of patients reported adverse events (61% balsalazide vs. 65% mesalazine). There were five serious adverse events (two balsalazide, three mesalazine) and four withdrawals due to unacceptable adverse events (three balsalazide, one mesalazine), of which one in each group was also a serious adverse event.Conclusions:Balsalazide 3 g/day and mesalazine 1.2 g/day effectively maintain UC remission and are equally well tolerated over 12 months. At this dose balsalazide prevents more relapses during the first 3 months of treatment and controls nocturnal symptoms more effectively.