bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of viscoelastic characteristics in triceps surae between Black and White athletes
Authors: FUKASHIRO S. , ABE T. , SHIBAYAMA A. , BRECHUE W. F.
Published: March 2003

The purpose of the present study was to investigate race differences in viscoelastic characteristics of triceps surae muscle group. Black and white college sprint type athletes (n=44) participated in this study. Viscoelastic properties were assessed using the free vibration technique: subjects sat with their forefeet on the edge of a force‐plate (Kistler, Switzerland) and support a frame loaded with weights (0–40 kg) on the knees. Oscillations of the triceps surae and Achilles tendon system were initiated with a hand‐held hammer by tapping the weight load. Oscillations occur at frequencies of 3–6 Hz and were slightly damped. The damped oscillations in conjunction with the equation of motion of a damped mass‐spring model were used to calculate the viscosity of muscle (b), and the elasticity of muscle fibres (kd) and tendon (kt) in each subject. There were little significant differences in most of physical characteristic variables between black and white athletes. Black athletes have significantly greater muscle viscosity and elasticity than white athletes while tendon elasticity is equivalent. Thus, muscle stiffness is greater among black athletes. Greater muscle stiffness could contribute to greater sprint/jump performance among black athletes, compared with white athletes, through alteration of foot/ground contact and take‐off phases during sprinting/jumping.
Cardiomyocyte contractility and calcium handling partially recover after early deterioration during post‐infarction failure in rat
Authors: Loennechen J. P. , Wisløff U. , Falck G. , Ellingsen Ø.
Published: March 2003

The aim of the study was to determine whether progression of heart failure is associated with deterioration of cardiomyocyte function. Cell dimensions, contractility and calcium transients were measured in cardiomyocytes isolated from the left ventricle of female Wistar rats 1, 4, and 13 weeks after coronary artery ligation or sham‐operation. Relative cardiomyocyte shortening decreased from 26% in controls to 11% 1 week after myocardial infarction and recovered to 18 and 20% after 4 and 13 weeks, respectively. Diastolic and systolic calcium concentrations increased markedly 1 week after myocardial infarction with subsequent reduction after 4 and 13 weeks. Time to 50% relaxation was prolonged by 31% after 1 week and 20% after 4 and 13 weeks with corresponding changes in diastolic calcium clearance. Cardiomyocyte length increased by 6, 24, and 26% after 1, 4 and 13 weeks, respectively, whereas myocyte width increased by 4, 11 and 27%. Cardiomyocytes adjacent to the infarct hypertrophied more and initially had more markedly impaired function than in the remote area. Left ventricular diastolic diameter assessed by echocardiography increased by 47, 66 and 84% after 1, 4 and 13 weeks, respectively, and systolic diameter increased by 120, 162 and 194%. Left ventricular end‐diastolic pressure increased from 6 mmHg to 24, 25 and 36 mmHg. Whereas initial deterioration of cardiac function is associated with reduced cardiomyocyte contractile function, chronic heart failure progression is not accompanied by further impairment of intrinsic cardiomyocyte contractility in this model. Cardiomyocyte hypertrophy and dysfunction are more marked adjacent to the infarction.
Reduced rat renal vascular response to angiotensin II after chronic inhibition of nNOS
Authors: Ollerstam A. , Salomonsson M. , Persson A. E. G.
Published: March 2003

The neuronal isoform of nitric oxide synthase (nNOS) in the kidney is predominantly located in the macula densa (MD) cells. These cells are known to be the sensor in the tubuloglomerular feedback, which influences the tonus of the afferent arteriole. This study investigated the effect of angiotensin II (Ang II) after chronic inhibition of nNOS on renal blood flow (RBF) and cytosolic calcium concentration [Ca2+]i in smooth muscle cells from afferent arterioles. Measurements of RBF were made in two control groups and two groups treated with a nNOS inhibitor, 7‐nitro indazole (7‐NI), for 1 and 4 weeks. At the time of the experiment Ang II bolus was given in the renal artery before and during i.v. l‐NNA. [Ca2+]i was measured in arterioles from control rats and from rats treated for 1 week with 7‐NI. RBF decreased after bolus Ang II by 60 ± 11% in the control vs. 23 ± 8% in the 1 week 7‐NI treated group. The decreased sensitivity to Ang II after 1 week of 7‐NI treatment compared with control rats persisted after l‐NNA infusion. There were no differences from control in the group treated for 4 weeks. Ang II gave a transient [Ca2+]i increase in vessels from control rats whereas this response was absent in 1 week 7‐NI‐treated rats. A possible explanation for these findings could be a down regulation of Ang II receptors. The renal vasculature of rats exhibits a diminished RBF and [Ca2+]i response to Ang II after 1 week blockade of nNOS.
Differential strain patterns of the human gastrocnemius aponeurosis and free tendon, in vivo
Authors: Magnusson S. P. , Hansen P. , Aagaard P. , Brønd J. , Dyhre‐Poulsen P. , Bojsen‐Moller J. , Kjaer M.
Published: March 2003

Aim:  The mechanical characteristics of the human free tendon and aponeurosis, in vivo, remains largely unknown. The present study evaluated the longitudinal displacement of the separate free Achilles tendon and distal (deep) aponeurosis of the medial gastrocnemius muscle during voluntary isometric contraction.

Methods:  Ultrasonography‐obtained displacement of the free tendon and tendon–aponeurosis complex, electromyography of the gastrocnemius, soleus, and dorsiflexor muscles, and joint angular rotation were recorded during isometric plantarflexion (n = 5). Tendon cross‐sectional area, moment arm and segment lengths (Lo) were measured using magnetic resonance imaging. Tendon force was calculated from joint moments and tendon moment arm, and stress was obtained by dividing force by cross‐sectional area. The difference between the free tendon and tendon–aponeurosis complex deformation yielded separate distal aponeurosis deformation. Longitudinal aponeurosis and tendon strain were obtained from the deformations normalized to segment lengths.

Results:  At a common tendon force of 2641 ± 306 N, the respective deformation and Lo were 5.85 ± 0.85 and 74 ± 0.8 mm for the free tendon and 2.12 ± 0.64 and 145 ± 1.3 mm for the distal aponeurosis, P < 0.05. Longitudinal strain was 8.0 ± 1.2% for the tendon and 1.4 ± 0.4% for the aponeurosis, P < 0.01. Stiffness and stored energy was 759 ± 132 N mm−1 and 6.14 ± 1.89 J, respectively, for the free tendon. Cross‐sectional area of the Achilles tendon was 73 ± 4 mm2, yielding a stress of 36.5 ± 4.6 MPa and Young's modulus of 788 ± 181 MPa.

Conclusion:  The free Achilles tendon demonstrates greater strain compared with that of the distal (deep) aponeurosis during voluntary isometric contraction, which suggests that separate functional roles may exist during in vivo force transmission.
Sympathetic vasodilation in human muscle
Authors: Joyner M. J. , Dietz N. M.
Published: March 2003

The idea that there might be sympathetic vasodilator nerves to skeletal muscle is an old concept that fits with the archaic ‘fight or flight’ model of the sympathetic nervous system. Clear evidence for vasodilator nerves to skeletal muscle began to emerge in animals during the 1930s, when stimulation of selected brainstem areas was shown to evoke hypertension, tachycardia and skeletal muscle vasodilation (i.e. the ‘defense reaction’). By the 1940s and 1950s this idea was well established and it was shown in animals that the sympathetic dilator nerves to muscles were cholinergic. During this time, circumstantial evidence began to suggest the existence of sympathetic cholinergic vasodilator fibres in human skeletal muscle. In this context, the well‐ known forearm vasodilator response to mental stress was shown to be atropine‐sensitive, and absent after surgical sympathectomy. However, while there was clear histological evidence for sympathetic cholinergic dilator fibres in animal muscle, such evidence was not seen in humans. Additionally, attempts to record from sympathetic dilator fibres human muscle have never demonstrated clear evidence for dilator nerve traffic, and many ‘sympathetic dilator’ responses are still present after local anaesthetic nerve block. More recently, the skeletal muscle dilator response to sympathoexcitatory manoeuvres in both humans and animals appears to be nitric oxide (NO)‐dependent. While there are clearly atropine‐sensitive and NO‐dependent dilator nerves to skeletal muscles in animals, our current thinking is that most ‘sympathetic dilator’ responses in human muscle are due to adrenaline or local cholinergic mechanisms acting to stimulate NO release from the vascular endothelium.
A checklist of the dragonflies (Odonata) of Kenya
Authors: Clausnitzer Viola
Published: March 2003

A checklist of Odonata has been compiled for Kenya. It is based on an inventory of museum material, publications and personal observations made between 1978 and 1997. Changes of scientific names and synonyms are documented. The list contains 194 valid dragonfly species recorded for Kenya.
Daylight occurrence of humpback dolphins Sousa chinensis in Algoa Bay, South Africa
Authors: Karczmarski Leszek , Thornton Meredith , Cockcroft Victor G.
Published: March 2003

This paper describes the pattern of daylight occurrence of humpback dolphins Sousa chinensis in Algoa Bay, the Eastern Cape, South Africa, between May 1991 and May 1994. Two indices, the Sighting Index (SI) and the Total Recorded Dolphin Presence (TRDP), were used to quantify the dolphins' daylight occurrence. Humpback dolphins display a clear pattern of daylight occurrence in Algoa Bay and can be seen mostly in the morning, and, to a lesser extent, in the evening. This pattern varies little between seasons (with possible exception for the evening hours), follows the time of the solar day, is not related to the tidal cycle and is probably governed by the diurnal cycles of dolphins' prey.
A reassessment of the fire‐tolerance of some miombo woody species in the Central Province, Zambia
Authors: Cauldwell A. E. , Zieger U.
Published: March 2003

The fire‐tolerance of 21 woody species in a dry miombo woodland in the Central Province, Zambia was evaluated and compared to an existing classification. The evaluation is based on differences in the vertical distribution of canopy volumes over a range of height intervals after repeated exposure of woodlands to fire. Woody species that showed an inverse correlation between canopy volume and tree height were classified as fire‐sensitive, whilst those that showed a positive correlation were classified as fire‐tolerant. A new method of a rapid and simple field evaluation is described, and further applications are discussed.
Maintaining diversity through intermediate disturbances: evidence from rodents colonizing rehabilitating coastal dunes
Authors: Ferreira S. M. , Van Aarde R. J.
Published: March 2003

Rodents 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

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

Echuya 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

The 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.
Review article: olestra and its gastrointestinal safety
Authors: Thomson  , Hunt  , Zorich
Published: March 2003

Olestra is a fat substitute made from sucrose and vegetable oil. Olestra is neither digested nor absorbed, and therefore adds no calories or fat to the diet. Because the gut is the only organ that is exposed to olestra, the potential for olestra to affect gastrointestinal structure and function, and the absorption of nutrients from the gut, has been investigated. Histological evaluations performed after long‐term feeding studies have shown no indications that olestra causes injury to the gastrointestinal mucosa. Olestra is not metabolized by the colonic microflora, and has no meaningful effects on the metabolic function of these organisms. Studies of gastrointestinal transit have shown that the consumption of olestra with food does not affect gastric emptying, or small or large bowel transit times. Olestra does not affect the absorption of macronutrients, water‐soluble vitamins or minerals. It causes a dose‐responsive decrease in the availability of the fat‐soluble vitamins A, D, E and K; however, this potentially adverse effect is offset by the addition of vitamins to olestra‐containing foods. Olestra has no consistent effect on the amount of total bile acids excreted in the faeces, and therefore probably has no significant effect on bile acid absorption. The occurrence of gastrointestinal symptoms, including diarrhoea, loose stools, gas and abdominal cramping, after consumption of olestra under ordinary snacking conditions is comparable to that following consumption of triglyceride‐containing snacks.
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.
Evaluation of a new ultrashort triple therapy for Helicobacter pylori disease
Authors: Trevisani  , Sartori  , Galvani  , Ruina  , Caselli  , Verdianelli  , Abbasciano
Published: March 2003

Background:

1‐week proton pump inhibitor‐based triple therapies are considered the most effective and convenient drug combinations for curing Helicobacter pylori infection. Short therapies, lasting less than 1 week have been investigated rarely.

Aim:

To assess the efficacy and tolerability of a 3‐day lansoprazole triple therapy after 1 day of lansoprazole pre‐treatment.

Methods:

Seventy H. pylori‐positive (rapid urease test and histology) patients received LAzT3 regimen (lanzoprazole 30 mg b.d. and azithromycin 500 mg o.m. for 3 days; tinidazole 2000 mg o.m. on day 1 and 1000 mg o.m. on days 2–3) after 1 day of lansoprazole pre‐treatment. Patients with active ulcer received lansoprazole 30 mg o.m. for an additional 4 weeks. Follow‐up gastroscopy was carried out 4–6 weeks after completion of therapy. Eradication was defined as negative histology and rapid urease test.

Results:

Four patients failed to attend the follow‐up endoscopy. One patient complained of minor side‐effects. H. pylori was eradicated in 57 of 66 patients suitable for evaluation, with a per‐protocol cure rate of 86.3% (95%CI: 76–94%), and an intention‐to‐treat cure rate of 81.4% (95%CI: 70–90%).

Conclusions:

This new ultrashort triple therapy including lansoprazole, azithromycin and tinidazole seems to be effective in eradicating H. pylori. It is safe and well‐tolerated, and may be taken into consideration as a valid alternative to the better known and widely used 1‐week proton pump inhibitor‐based triple therapies.
Plaunotol prevents indomethacin‐induced gastric mucosal injury in rats by inhibiting neutrophil activation
Authors: MURAKAMI  , OKAJIMA  , HARADA  , ISOBE  , LIU  , JOHNO  , OKABE
Published: March 2003

Background:

Activated neutrophils play a critical role in indomethacin‐induced gastric mucosal injury.

Aim:

To investigate the effect of plaunotol, an anti‐ulcer agent, on neutrophil activation in vitro and its effect on gastric mucosal injury and gastric accumulation of neutrophils in rats given indomethacin.

Methods:

Human monocytes and neutrophils were isolated from the peripheral blood of healthy volunteers. We examined the effect of plaunotol on neutrophil elastase release, production of O2−, intracellular calcium concentration and expression of adhesion molecules CD11b and CD18 in activated neutrophils in vitro. The effect of plaunotol on TNF‐α production by monocytes stimulated with endotoxin also was investigated in vitro. The effect of plaunotol (100 mg/kg, p.o.) on gastric mucosal injury and neutrophil accumulation was investigated in male Wistar rats given indomethacin (30 mg/kg, p.o.).

Results:

Plaunotol inhibited the fMLP‐induced release of neutrophil elastase from activated neutrophils, as well as the opsonized zymosan‐induced production of O2− by neutrophils. Plaunotol significantly inhibited increased levels of intracellular calcium, a second messenger of neutrophil activation, in vitro. The fMLP‐induced increases in CD11b and CD18 expression were also inhibited by plaunotol in vitro. Plaunotol inhibited monocytic production of TNF‐α, a potent activator of neutrophils. Both gastric mucosal injury and gastric neutrophil infiltration in rats given indomethacin were significantly inhibited by the oral administration of plaunotol.

Conclusions:

Plaunotol inhibits indomethacin‐induced gastric mucosal injury, at least in part by inhibiting neutrophil activation.
Expression of endothelial cell‐derived nitric oxide synthase (eNOS) is increased during gastric adaptation to chronic aspirin intake in humans
Authors: FISCHER  , BECKER  , BOKNIK  , HUBER  , LÜSS  , NEUMANN  , SCHMITZ  , DOMSCHKE  , KONTUREK
Published: March 2003

Background

: Gastric adaptation to aspirin is well‐documented. However, the mechanisms underlying the reduction of aspirin‐induced mucosal damage despite continued ingestion of the drug remain poorly understood.

Methods

: Eight healthy volunteers who received aspirin 1 g b.d. for 14 days were compared with eight placebo‐dosed controls. Gastroscopy with mucosal biopsy was performed, and gastric mucosal blood flow was measured before and following 3, 7 and 14 days of aspirin treatment. At the same time points, tissue concentration and the content of prostaglandin E2 in the gastric juice were determined and expression of endothelial cell‐derived nitric oxide synthase (eNOS) in mucosal biopsies was measured using Western blot analysis.

Results

: Aspirin‐induced mucosal damage that reached a maximum on day 3, declining significantly by day 14. Concomitantly, mucosal blood flow significantly increased on day 3 and returned to initial values on day 14. Aspirin intake led to a significant decrease in prostaglandin E2 concentration in the gastric mucosa and in gastric juice during the whole period of aspirin consumption. eNOS expression started to increase on day 7 in oxyntic mucosa and on day 3 in antral mucosa, reaching its highest values at the end of the consumption of aspirin.

Conclusions

: The human gastric mucosa adapts to prolonged aspirin intake, and this is accompanied by an increase in mucosal blood flow and reduced prostaglandin synthesis. Increase of mucosal eNOS expression might compensate for reduced prostaglandin synthesis and be responsible for gastric adaptation to chronic aspirin intake in humans.
Efficacy of a 1‐week regimen of ranitidine bismuth citrate in combination with metronidazole and clarithromycin for Helicobacter pylori eradication
Authors: HOFFMAN  , KATZ  , CAVE
Published: March 2003

Background

: In order to improve the efficacy and simplicity of the FDA‐approved regimen of ranitidine bismuth citrate (RBC) and clarithromycin dual therapy, we added an inexpensive antibiotic (metronidazole), changed the dosage scheme to twice daily dosing, and decreased the duration of therapy to 1 week.

Methods

: This was an open label study in which subjects with previously untreated Helicobacter pylori infection documented by serology or endoscopy and confirmed by the 13C‐urea breath test received a 1‐week course of RBC 400 mg b.d., metronidazole 500 mg b.d. and clarithromycin 500 mg b.d. A repeat breath test was performed 4–6 weeks after completing therapy.

Results

: Forty‐seven out of 50 subjects completed the protocol. Intention‐to‐treat and per protocol cure rates were 86% and 91%, respectively. The regimen was well tolerated. Study drugs were stopped in two patients due to side‐effects. The most common side‐effect was self‐limited diarrhoea.

Conclusion

: Twice daily RBC‐based triple therapy with metronidazole and clarithromycin for 1 week is well tolerated and effective in eradicating H. pylori infection.
Ecabet sodium, a novel locally‐acting anti‐ulcer agent, protects the integrity of the gastric mucosal gel layer from pepsin‐induced disruption in the rat
Authors: KINOSHITA  , ENDO  , YASOSHIMA  , SAITO  , YAMASAKI  , CHISHIMA  , NARITA
Published: March 2003

Background

: Ecabet sodium, a novel non‐systemic anti‐ulcer agent, possesses high affinity to gastric adherent mucus, which plays an important role in the protection of the gastric epithelium against acid and pepsin.

Aim

: To assess the effect of ecabet on pepsin‐induced degradation of the structure of the mucus gel layer.

Methods

: Everted sacs of rat stomach were incubated in HCl solution containing pepsin with or without ecabet. Pepsin‐induced release of the cleaved peptides and hexosamine from the sacs was determined. Changes in the molecular size of glycoproteins in the adherent mucus (using gel filtration methods) and in the morphology of the epithelium (using both light and scanning electron microscopy) were also examined.

Results

: Ecabet reduced the pepsin‐induced release of peptides and hexosamine, depending on its content in the adherent mucus. Pepsin treatment partially lowered the molecular weight of native glycoproteins in the adherent mucus, caused exfoliation of the epithelial cells, and degraded the network‐like ultrastructure of the mucus layer, giving it a lumpy, globular appearance. Ecabet prevented both the pepsin‐induced molecular size shift in mucus glycoproteins, and morphological alteration of the epithelium, including ultrastructural derangement of the mucus gel layer.

Conclusion

: Ecabet protects the polymeric structure of mucus glycoproteins from proteolytic degradation by pepsin, and thus maintains integrity of the gastric mucus gel layer.
A non‐toxic analogue of a coeliac‐activating gliadin peptide: a basis for immunomodulation?
Authors: Biagi  , Ellis  , Parnell  , Shidrawi  , Thomas  , O’reilly  , Corazza  , Ciclitira
Published: March 2003

Background

: A‐gliadin residues 31–49 (peptide A) binds to HLA‐DQ2 and is toxic to coeliac small bowel. Analogues of this peptide, which bind to DQ2 molecules but are non‐toxic, may be a potential route to inducing tolerance to gliadin in patients with coeliac disease.

Methods

: Toxicity was investigated with small bowel organ culture in six patients with untreated coeliac disease, four with treated coeliac disease and six controls. Analogue peptides comprised alanine substituted variants of peptide A at L31 (peptide D), P36 (E), P38 (F), P39 (G) and P42 (H).

Results

: Peptides D and E were toxic in biopsies from some patients. Peptides F, G and H were not toxic.

Conclusions

: Peptide F, which binds to DQ2 more strongly than peptide A, is not toxic in patients with coeliac disease in‐vitro; this could be an initial step towards investigation of the induction of tolerance to gliadin in patients affected by coeliac disease.
Randomized controlled comparison of nitroimidazoles for the eradication of Helicobacter pylori and relief of ulcer‐associated and non‐ulcer dyspepsia
Authors: GODDARD  , LOGAN  , LAWES  , SPILLER
Published: March 2003

Background

: A combination of omeprazole, clarithromycin and either metronidazole or tinidazole is commonly used for Helicobacter pylori eradication. Metronidazole is considerably cheaper than tinidazole but the two have not previously been compared in a randomized trial.

Methods

: One hundred and twenty dyspeptic H. pylori‐positive patients with endoscopically defined peptic ulcer [DU (n = 65), GU (n = 12)] or non‐ulcer dyspepsia (NUD, n = 43) were randomized to receive a 1‐week course of twice daily omeprazole 20 mg, clarithromycin 250 mg and either metronidazole 400 mg (OCM) or tinidazole 500 mg (OCT) in a double‐blind fashion. Eradication of H. pylori, safety and side‐effects of treatment, dyspeptic symptom score and consumption of antisecretory drugs were assessed at 6 weeks and 1 year after treatment.

Results

: H. pylori eradication was successfully achieved in 57/60 (95%, ITT analysis) of patients receiving OCT and 58/60 (97%, ITT analysis) receiving OCM. Both regimens had similar side‐effect profiles, which accounted for only one patient withdrawal. All patients remained uninfected (as assessed by 14C‐urea breath test) at 1‐year follow‐up, but major symptom improvements and decreased antisecretory drug use were only seen in patients with DU (P < 0.0001).

Conclusions

: Treatment with OCM is as effective as the more expensive OCT at eradicating H. pylori. H. pylori eradication results in long‐term relief of dyspeptic symptoms and reduced antisecretory consumption only in patients with DU, and not in those with NUD.