bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in Liana Abundance and Species Diversity Eight Years after Liana Cutting and Logging in an Eastern Amazonian Forest
Authors: Gerwing Jeffrey J. , Vidal Edson
Published: March 2003

Abstract: Lianas are characteristic of many tropical forests and may serve multiple ecosystem functions. They can also increase logging damage and slow tree growth. Liana cutting prior to logging is a silvicultural tool used to mitigate these negative effects. We assessed the effects of complete liana cutting followed by reduced‐impact logging on liana abundance and species diversity. Eight years following liana cutting and 6 years following logging there was a 55% reduction in the stem density of climbing lianas ≥1 cm diameter in size. Liana basal area, aboveground biomass, and leaf area index decreased by approximately 85%. Coppicing of cut stems was the primary mode of liana recruitment. Liana cutting and logging resulted in a 14% reduction in the number of liana species present in a 0.20‐ha sample, but a cumulative species‐area curve suggested that this percentage might have been reduced if a larger area were sampled. Our results suggest that the silvicultural benefits of complete liana cutting—reduced logging damage and increased postlogging tree growth—need to be weighed against the costs of reduced species diversity of lianas and the possible effects on forest ecosystem functioning (e.g., reduced fruit and flower availability) that are likely to persist long after initial liana cutting.
Comparative Ecology of Four Passerine Species in Jarrah Forests Used for Timber Production in Southwestern Western Australia
Authors: Craig Michael D.
Published: March 2003

Abstract: I assessed which resources were critical for bird species that decline after selective logging. I compared foraging and nesting behaviors of Western Yellow Robins (   Eopsaltria griseogularis), Rufous Treecreepers (Climacteris rufa), Golden Whistlers (   Pachycephala pectoralis), and White‐naped Honeyeaters (   Melithreptus lunatus) before and after logging in jarrah forests used for timber production in southwestern Australia. Species that declined after logging (Golden Whistler, White‐naped Honeyeater) foraged in the canopy and displayed little flexibility in foraging behavior. Species that did not decline (  Western Yellow Robin, Rufous Treecreeper) foraged lower, spent a variable proportion of time on the ground and displayed greater flexibility in foraging behavior. Rufous Treecreepers, obligate tree‐hollow nesters, and Western Yellow Robins did not alter nesting sites after logging, but Golden Whistlers nested infrequently in logged areas. There were no consistent differences in the nesting ecologies of the two groups, and it is unclear why Golden Whistlers nested infrequently in logged forest. Western Yellow Robins and Rufous Treecreepers used logged forest as frequently after logging as before and did not appear to require unlogged buffers to persist in forests used for timber production. In contrast, Golden Whistlers used logged forests less frequently after logging and moved their territories to include unlogged buffers. Retention of critical resources for Golden Whistlers and White‐naped Honeyeaters in logged forest is unlikely to be feasible because of the effects on timber yield, emphasizing the importance of unlogged buffers in forest management.
Compatibility of Prescribed Burning with the Conservation of Insects in Small, Isolated Prairie Reserves
Authors: Panzer Ron
Published: March 2003

Abstract: Entomologists have expressed concern that prescribed burning is incompatible with the conservation of insect species richness on small prairie sites. To address this issue, I examined the response and recovery of insect populations after fire within small, isolated tallgrass prairie remnants in northern Illinois, northwestern Indiana, and southeastern Wisconsin. I conducted this research over seven seasons, focused on responses at the species level, distinguished between remnant‐dependent and remnant‐independent species, and included multiple fire events and sites. I used sweep nets, light traps, sticky traps, and visual searches to gauge population responses and to track negatively affected populations to recovery. Most species (93%) responded consistently to prescribed fires. Postfire responses ranged from positive (26%) to negative (40%) for 151 species representing 33 families and seven orders. Three attributes—remnant‐dependence, upland inhabitance, and nonvagility—were significant predictors of negative postfire response. Among negatively affected populations, 68% recovered within 1 year; all 163 populations tracked to recovery did so in 2 years or less. My results support the judicious use of rotational cool‐season burning within small, isolated grassland sites.
Rapid Genetic Decline in a Translocated Population of the Endangered PlantGrevillea scapigera
Authors: Krauss Siegfried L. , Dixon Bob , Dixon Kingsley W.
Published: March 2003

Abstract:Grevillea scapigerais one of the world's rarest plant species, currently known from only five plants in the wild. In 1995, 10 plants were selected from the 47 plants known at the time to act as genetically representative founders for translocation into secure sites. Ramets were micropropagated and introduced into one of these secure sites (Corrigin) in 1996, 1997, and 1998. By late 1998, 266 plants had been successfully translocated and were producing large numbers of seeds. With the development of an artificial seed‐germination technique and because of an absence of seed germination in situ, seed was collected from these plants and germinated ex situ, and 161 seedlings were returned to the field site in winter 1999. We used the DNA fingerprinting technique of amplified fragment‐length polymorphism (AFLP) to (1) assess the genetic fidelity of the clones through the propagation process, (2) contrast genetic variation and average genetic similarities of the F1s to their parents to assess genetic decline, and (3) assign paternity to the reintroduced seeds to assess the reproductive success of each clone. We found that 8 clones, not 10, were present in the translocated population, 54% of all plants were a single clone, and the F1s were on average 22% more inbred and 20% less heterozygous than their parents, largely because 85% of all seeds were the product of only 4 clones. Ultimately, effective population size (  Ne ) of the founding population was approximately two. Our results highlight the difficulty of maintaining genetic fidelity through a large translocation program. More generally, rapid genetic decline may be a feature of many translocated populations whenNeis small, which may ultimately threaten their long‐term survival. Strategies to reverse this genetic decline include equalizing founder numbers, adding new genotypes when discovered, optimizing genetic structure and plant density to promote multiple siring and reduce kinship, promoting natural seed germination in situ rather than artificially germinating seeds ex situ, and creating a metapopulation of numerous translocated populations to restore historical distribution patterns and processes.
Commonness and Long‐Term Survival in Fragmented Habitats:Primula elatioras a Study Case
Authors: Van Rossum Fabienne , Echchgadda Ghizlane , Szabadi Ildiko , Triest Ludwig
Published: March 2003

Abstract:In Flanders (northern Belgium), populations ofPrimula elatior( Primulaceae), an obligately outcrossing long‐lived perennial herb, are widely distributed in fragmented ancient deciduous forests. We used 15 allozyme loci to investigate population genetic variation and structure ofP. elatiorand quantified reproductive success in the form of fruit and seed production. Based on a sample of nine populations from Flemish forests, we related these variables to population size, density (interplant spacing within populations), and isolation. With only four polymorphic loci, the levels of genetic variation within populations were low compared with those of other species with similar life‐history traits. Small populations had significantly fewer alleles per locus than large populations but maintained high levels of heterozygosity. No effect of plant density was found on genetic variation within populations. Genetic differentiation among populations was low, indicating moderate levels of gene flow. Isolation by distance was observed, however, and small populations appeared to be more differentiated than large populations. These findings suggest genetic drift as a cause of loss of variation and divergence. Population size and plant density were correlated but affected fruit and seed production differently. A reduced seed production was found in small populations. Fruit abortion increased at high plant densities as a result of biparental inbreeding and neighborhood genetic structure. Our results indicate that being common is not a guarantee of long‐term survival in fragmented habitats. Conservation efforts must include widely distributed species so as to prevent population collapses and consequent species decline. Forest management has to take into consideration the preservation of the herbaceous layer and avoid logging practices that damage populations of forest herbs.
Genetic Identification of Pelagic Shark Body Parts for Conservation and Trade Monitoring
Authors: Shivji Mahmood , Clarke Shelley , Pank Melissa , Natanson Lisa , Kohler Nancy , Stanhope Michael
Published: March 2003

Abstract: The conservation and management of sharks on a species‐specific basis is a pressing need because of the escalating demand for shark fins and the recognition that individual shark species respond differently to exploitation. Difficulties with the identification of many commonly fished sharks and their body parts has resulted in a global dearth of catch and trade information, making reliable assessment of exploitation effects and conservation needs for individual species nearly impossible. We developed and tested a highly streamlined molecular genetic approach based on species‐specific, polymerase‐chain‐reaction primers in an eight‐primer multiplex format to discriminate simultaneously between body parts from six shark species common in worldwide pelagic fisheries. The species‐specific primers are based on DNA sequence differences among species in the nuclear ribosomal internal transcribed spacer 2 locus. The primers and multiplex format accurately and sensitively distinguished samples from each of three lamnid (   Isurus oxyrinchus, Isurus paucus, and Lamna nasus) and three carcharhinid (   Prionace glauca, Carcharhinus obscurus, and Carcharhinus falciformis) species from all but one other shark species encountered in the North Atlantic fishery. Furthermore, the three lamnid primers were robust enough in their discriminatory power to be useful for species diagnosis on a global scale. Preliminary testing of dried fins from Asian and Mediterranean commercial markets suggests that our genetic approach will be useful for determining the species of origin of detached fins, thus allowing the monitoring of trade in shark fins for conservation assessment. Our approach will also facilitate detection of products from protected and other at‐risk shark species and may prove useful as a model for development of the high‐throughput, genetic, species‐diagnosis methods typically required in conservation and management contexts.
Synchronous Variation and Long‐Term Trends in Two Populations of Black Rat Snakes
Authors: Weatherhead P. J. , Blouin‐Demers G. , Prior K. A.
Published: March 2003

Abstract: Synchronous variation among animal populations affects the vulnerability of endangered species and is relevant to understanding population fluctuation generally. We analyzed data collected over 18 years from two populations of black rat snakes (  Elaphe o. obsoleta), a species of conservation concern in Canada, to determine whether the populations varied synchronously. Because the populations were 30 km apart and genetically distinct, synchrony should be attributable to common stochastic environmental factors, the Moran effect. Synchronous variation in annual estimates of population size, survival probability, recruitment, and age structure all provided evidence of a Moran effect. However, opposite trends in age structure through time suggested that the internal dynamics of the two populations were different. The conservation implication of synchrony is that this population of rat snakes is vulnerable to stochastic environmental phenomena because all subpopulations could become rare simultaneously. Evidence of different population processes in the two populations suggests, however, that local factors may be of more immediate relevance to conservation than regional phenomena. More generally, these results indicate that evidence of synchronous variation in population size and similar long‐term population trends—both populations appeared to be declining—are not necessarily indicative of common underlying population dynamics.
Evaluation of One‐to‐One Midwifery: Women's Responses to Care
Authors: McCourt Christine , Page Lesley , Hewison Jenny , Vail Andy
Published: March 2003

Background:

One‐to‐one midwifery was a demonstration project introduced into a London‐based maternity service in 1993 to put into practice the new government policy for maternity services in England. Evaluation was integral to the development of the project.

Methods:

The evaluation of women's responses was conducted between August 1994 and August 1995 based on a longitudinal, self‐completion questionnaire, interviews, and focus groups. Women in the study group (n= 728) received the new service and women in the control group (n= 675) received conventional care. The study design integrated quantitative and qualitative methods and went beyond a simple estimation of satisfaction with care.

Results:

Satisfaction with antenatal and birth care was generally high, but study group women showed more positive responses overall. Both groups showed a preference for continuity of caregiver, but expectations were higher in the study group (72% of the study group and 42% of the control group preferred to see one caregiver). Both groups had less satisfied responses to hospital postnatal care (50% study and 54% control group were very satisfied). Study group women showed greater preparedness for birth than control group women (18% vs 12%“very well prepared”) and for the time after the baby's birth (26% vs 15%“very prepared”).

Conclusions:

The study demonstrated that women were more satisfied with the one‐to‐one model of care. Taken together with the results of clinical and economic audit and professional responses, the evaluation suggests that this model should be developed and evaluated further to gain a greater understanding of women's needs of the maternity service. (BIRTH 25:2 June 1998)
Breast Stimulation to Augment Labor: History, Mystery, and Culture
Authors: Curtis Peter
Published: March 2003

This paper describes the development of a researchable project, arising from the clinical observation of a physiologic phenomenon during labor. Augmentation of labor by breast stimulation has been used in a variety of cultures for centuries. The process of developing a clinical study of augmentation in the modern obstetric environment is discussed, with reference to cultural attitudes of patients and health care workers.
Medical Hypnosis for Hyperemesis Gravidarum
Authors: Simon Eric P. , Schwartz Jennifer
Published: March 2003

Hyperemesis gravidarum in pregnancy is a serious condition that is often resistant to conservative treatments. Medical hypnosis is a well‐documented alternative treatment. This article reviews the empirical studies of medical hypnosis for treating hyperemesis gravidarum, explains basic concepts, and details the treatment mechanisms. The importance of a thorough differential diagnosis and appropriate referrals is stressed. The article presents three case studies to illustrate the efficacy of this treatment approach. It is suggested that medical hypnosis should be considered as an adjunctive treatment option for those women with hyperemesis gravidarum. It is also stressed that medical hypnosis can be used to treat common morning sickness that is experienced by up to 80 percent of pregnant women. Its use could allow a more comfortable pregnancy and healthier fetal development, and could prevent cases that might otherwise proceed to full‐blown hyperemesis gravidarum.
Maternal Mortality, United States and Canada, 1982–1997
Authors: Hoyert Donna L. , Danel Isabella , Tully Patricia
Published: March 2003

Background:
The 1998 public awareness campaign on Safe Motherhood called attention to the issue of maternal mortality worldwide. This paper focuses upon maternal mortality trends in the United States and Canada, and examines differentials in maternal mortality in the United States by maternal characteristics. Methods:Data from the vital statistics systems of the United States and Canada were used in the analysis. Both systems identify maternal deaths using the definition of the World Health Organization's International Classification of Diseases. Numbers of deaths, maternal mortality rates, and confidence intervals for the rates are shown in the paper. Results:Maternal mortality declined for much of the century in both countries, but the rates have not changed substantially between 1982 and 1997. In this period the maternal mortality levels were lower in Canada than in the United States. Maternal mortality rates vary by maternal characteristics, especially maternal age and race. Conclusions:Maternal mortality continues to be an issue in developed countries, such as the United States and Canada. Maternal mortality rates have been stable recently, despite evidence that many maternal deaths continue to be preventable. Additional investment is needed to realize further improvements in maternal mortality.
Team Midwifery Care in a Tertiary Level Obstetric Service: A Randomized Controlled Trial
Authors: Biró Mary Anne , Waldenström Ulla , Pannifex Jan H
Published: March 2003

Background:
In 1996 a new model of maternity care characterized by continuity of midwifery care from early pregnancy through to the postpartum period was implemented for women attending Monash Medical Centre, a tertiary level obstetric service, in Melbourne, Australia. The objective of this study was to compare the new model of care with standard maternity care.
Methods:
In a randomized controlled trial, 1000 women who booked at the antenatal clinic and met the eligibility criteria were randomly allocated to receive continuity of midwifery care (team care) from a group of seven midwives in collaboration with obstetric staff, or care from a variety of midwives and obstetric staff (standard care). The primary outcome measures were procedures in labor, maternal outcomes, neonatal outcomes, and length of hospital stay.
Results:
Women assigned to the team care group experienced less augmentation of labor, less electronic fetal monitoring, less use of narcotic and epidural analgesia, and fewer episiotomies but more unsutured tears. Team care women stayed in hospital 7 hours less than women in standard care. More babies of standard care mothers were admitted to the special care nurseries for more than 5 days because of preterm birth, and more babies of team care mothers were admitted to the nurseries for more than 5 days with intrauterine growth retardation. No differences occurred in perinatal mortality between the two groups.
Conclusions:
Continuity of midwifery care was associated with a reduction in medical procedures in labor and a shorter length of stay without compromising maternal and perinatal safety. Continuity of midwifery care is realistically achievable in a tertiary obstetric referral service.
Single Room Maternity Care and Client Satisfaction
Authors: Janssen Patricia A , Klein Michael C , Harris Susan J , Soolsma Jetty , Seymour Laurie C
Published: March 2003

Background:
Single room maternity care is the provision of intrapartum and postpartum care in a single room. It promotes a philosophy of family centered care in which one nurse cares for the family consistently throughout the intrapartum and postpartum periods. At B.C. Women's Hospital, a tertiary level obstetric teaching hospital in Vancouver, British Columbia, a seven‐bed, single room maternity care unit was developed and opened as a demonstration project. As part of the evaluation of this unit, client satisfaction was compared between women enrolled in single room maternity care and those in a traditional setting.
Method:
The study group included 205 women who were admitted to the single room maternity care unit after meeting the low‐risk criteria. Their responses on a satisfaction survey were compared with those of a historical comparison group of 221 women meeting the same eligibility criteria who were identified through chart audits 3 months before the single room maternity care unit was opened. A second, concurrent comparison group comprised 104 women who also met eligibility criteria.
Results:
Study group women were more satisfied than comparison groups in all areas evaluated, including provision of information and support, physical environment, nursing care, patient education, assistance with infant feeding, respect for privacy, and preparation for discharge.
Conclusions:
Single room maternity care was associated with a significant improvement in client satisfaction because of many factors, including the physical setting itself, avoidance of transfers, and improved continuity of nursing care.
Eating and Drinking in Labor: The Influence of Caregiver Advice on Women's Behavior
Authors: Scheepers Hubertina C.J. , Thans Marion C.J. , de Jong Pieter A. , Essed Gerard G.M. , Le Cessie Saskia , Kanhai Humphrey H.H.
Published: March 2003

Background:
Although there is much debate about eating and drinking during labor, little scientific data about its influence on the course of labor exist. In The Netherlands, most midwives and obstetricians allow women to eat and drink during normal labor. The objective of this study was to examine whether or not women were actively advised to eat and drink and if this advice affected eating and drinking behavior.
Methods:
A randomly selected group of midwives and obstetricians from across The Netherlands identified 211 consecutive nulliparous women to participate in the study. In a questionnaire with open‐ended questions, women were asked after their delivery whether or not they were advised about eating and drinking during labor, and if so, about the nature of this advice and what they had consumed. Data were analyzed at the Leyenburg Hospital in The Hague.
Results:
Sixty‐six percent of the women were not given advice about eating and drinking during labor. Women who were given advice usually followed it. In the total group, 37 percent of the women had intake other than water and of these, 75 percent ate solid food. After adjusting for other prognostic factors, the incidence of an instrumental delivery due to a nonprogressing second stage was lower in women with caloric intake (13% vs 24%, p = 0.04).Conclusion: The study design did not enable us to draw conclusions about the cause and effect between caloric intake and labor progress. Scientific data with respect to the giving of evidence‐based advice about eating and drinking during labor are lacking. Should such advice become available, women are likely to follow it.
Rates of Cesarean Births in Hong Kong: 1987–1999
Authors: Leung Gabriel M. , Lam Tai‐Hing , Thach Thuan Q. , Wan Simmy , Ho Lai‐Ming
Published: March 2003

Background: High cesarean birth rates are an issue of international public health concern. The purpose of this paper was to examine the annual incidence and secular trend of cesarean births in Hong Kong and to correlate these rates with socioeconomic, demographic, and health indicators for the population since 1987. Methods: This was a descriptive and ecologic study. Annual population rates of cesarean sections were estimated for 1987 from a population‐based survey, and for 1993 through 1999 from government data sources. The number of excess cesarean sections was calculated for each year using the 15 percent upper limit as proposed by the World Health Organization. Results: From 1987 to 1999 the overall annual cesarean section rate rose steadily from 16.6 to 27.4 per 100 hospital deliveries, resulting in a 65 percent increase over 12 years. The mean difference in rates of surgical delivery between public (meanpublic= 16.0%) and private (meanprivate= 43.4%) institutions was 27.4 percent (95% confidence interval (CI)

= 24.1, 30.7; p

< 0.001). Conclusions: This is the first systematic report of secular variations of cesarean delivery rates in Asia. The high rates and increasing trend represent an unnecessary excess risk for mothers and their infants. Various strategies combating high cesarean rates have been proposed and have succeeded elsewhere. Concerted action from health care professionals, public health authorities, the general population, and the media is urgently required to implement solutions to reduce the rate of cesarean delivery.
Postpartum Positioning and Attachment Education for Increasing Breastfeeding: A Randomized Trial
Authors: Henderson Ann , Stamp Georgina , Pincombe Jan
Published: March 2003

Background:
Although lactation experts suggest that a correct positioning and attachment technique reduces breastfeeding problems and enhances long‐term breastfeeding, evidence from randomized trials is lacking. The objective of this study was to evaluate the effect of postpartum positioning and attachment education on breastfeeding outcomes in first‐time mothers.
Method:
A randomized trial was performed in a public hospital in Adelaide, South Australia, where 160 first‐time mothers were randomly allocated to receive either structured one‐to‐one education (experimental group) or usual postpartum care (control group) within 24 hours of birth. The primary outcome was breastfeeding at 6 weeks and 3 and 6 months postpartum; other outcomes were nipple pain and trauma in hospital and at 6 weeks and 3 and 6 months, and satisfaction with breastfeeding.
Results:
No significant
differences occurred in breastfeeding rates between the groups at each endpoint, although a trend in the direction of lower rates was seen at each endpoint in the experimental group. This group reported less nipple pain on days 2 (p= 0.004) and 3 (p= 0.04), but this was not sustained on follow‐up. No differences were observed in nipple trauma in hospital or in self‐reported nipple pain and/or trauma at the three endpoints. Experimental group women were less satisfied with breastfeeding at 3 and 6 months postpartum when using a one‐item measure; however, a multiple‐item measure showed no significant differences at the three endpoints. Conclusions: The intervention did not increase breastfeeding duration at any assessment time or demonstrate any differences between the groups on secondary outcomes. The trend toward lower breastfeeding rates in the experimental group suggests a need for a larger trial to evaluate whether or nor postpartum positioning and attachment education may negatively affect breastfeeding.
Prepartum Work, Job Characteristics, and Risk of Cesarean Delivery
Authors: Hung Shirley , Morrison Donna Ruane , Whittington Leslie A. , Fein Sara Beck
Published: March 2003

Background: Reducing the rate of cesarean deliveries in the United States is a high priority among public health officials and members of the medical community. Many factors known to contribute to an individual woman's risk of having a cesarean rather than a vaginal delivery are not readily altered by public policy intervention. In this study we explored the effects on type of delivery of prepartum work practices, a category of factors that has a potential to affect the likelihood of cesarean delivery and to be amenable to change. Methods: Data are from U.S. Food and Drug Administration's Infant Feeding Practices Study, using questions on mail surveys administered prenatally and at 1 month postpartum. The sample comprised 1194 women who worked during pregnancy. The outcome measure is type of delivery. Predictor variables are characteristics of prepartum work: how far into their pregnancy the women work, number of hours worked, and occupation. Results: For most women, maintaining employment through the third trimester, working long hours, and working in certain occupations are not independently associated with the odds of having a cesarean delivery. However, we found marginally significant evidence that those women who worked more than 40 hours a week in a sales job were more likely to have cesarean deliveries than women who worked in other occupations. Conversely, women working part‐time in sales jobs were less likely to have a cesarean delivery. Conclusion: This study provides evidence that prenatal work does not substantially increase the probability of having a cesarean delivery in most occupational categories. (BIRTH 29:1 March 2002)
The Role of Gastric Helicobacter and N‐methyl‐N′‐nitro‐ N‐nitrosoguanidine in Carcinogenesis of Mice
Authors: Danon Stephen J. , Eaton Kathryn A.
Published: March 2003

Background.

The aim of this study was to determine whether gastric epithelial proliferation due to gastric Helicobacter infection in mice represents a preneoplastic lesion.

Materials and Methods.

Helicobacter heilmannii infected and uninfected mice were treated with 150 μg/ml N‐methyl‐N′‐nitro‐N‐nitrosoguanidine in drinking water for either 20 or 38 weeks. Mice were killed 12 or 18 months after bacterial inoculation.

Results.

All infected mice developed lymphoplasmocytic gastritis and epithelial hyperplasia. Proliferative gastric lesions were characterised by nodular hypertrophy of the glandular mucosa, multifocal epithelial hyperplasia, and elevated BrdU labeling index. Intestinal metaplasia and true atrophy were not present but proliferative glands were poorly differentiated, lined by mucus‐type epithelial cells with no parietal, chief or other specialized cell types. Neoplasms developed only in MNNG‐treated mice. of the 180 treated mice the following neoplasms developed: 14 squamous cell carcinomas of mouth and forestomach; 37 hemangiosarcomas of the intestinal serosa; and 15 splenic lymphomas. No tumors were present in the glandular gastric mucosa, and infection did not affect tumor incidence. p53 overexpression occurred in 79% of hemangiosarcomas and 71% of squamous cell carcinomas but not in normal or proliferative gastric glandular mucosa.

Conclusions.

Gastric proliferative lesions in Helicobacter‐infected mice are not preneoplastic, and the combination of an alkylating agent and non‐neoplastic proliferation does not result in gastric carcinogenesis in mice.
Optimal PPI‐based Triple Therapy for the Cure of Helicobacter pylori Infection: A Single Center Comparison of Four 14‐day Schedules
Authors: Battaglia Guiseppe , Mario Francesco Di , Leandro Gioacchino , Benvenuti Maria Eugenia , Donisi Pietro Maria , Vianello Fabio , Bò Nadia Dal , Pasini Michele , Pasquino Marcello , Vigneri Sergio
Published: March 2003

Background.

Helicobacter pylori eradication is accomplished using a wide array of drugs combined in a multitude of dosage schedules. The aim of the present study was to define the best 14‐day eradication schedule using a PPI plus either two antibiotics or one antibiotic and bismuth.

Material and Methods.

For this study, 367 subjects (198 males, 169 females, age 22–87 years) with document H. pylori infection of the stomach were recruited from outpatients of the Gastroenterology Department of the Venezia Hospital. In all patients, H. pylori infection was identified by histology and the CLO‐test. Patients were treated as follows: 1) PPI (P) plus clarithromycin (C) 250 mg plus amoxicillin (A) 1000mg bid (P+C+A); 2) P plus C plus bismuth subcitrate (B) 120 mg qid (P+C+B); 3) P plus C plus tinidazole (T) 500 mg bid (P+C+T); and 4) P plus A plus T bid (P+A+T). After two months, an upper gastrointestinal endoscopy was repeated for end point histological evaluation and the CLO‐ test. Positivity of one of the two methods was considered sufficient to define H. pylori as “not eradicated”. Statistics: Chi‐squared test and Fisher exact test.

Results.

Thirty‐three subjects dropped out (six due to adverse events). P+C+B was proven significantly less effective than P+C+A, P+C+T and P+A+T, eradication rates being, respectively, 75.0%, 90.5%, 87.6%, 92.0%, (p = .005, per protocol analysis).

Conclusions.

All PPI‐based triple therapies tested in this study were effective in curing H. pylori infection; however, P+C+B resulted in rates too low (< 85%) to be recommended. P+C+A and P+A+T resulted in the high cure rates and thus may be considered the treatment of choice.
Follow‐Up of Helicobacter pylori Positive Gastritis and Argyrophil Cells Pattern During the Natural Course of Gastric Ulcer
Authors: Maaroos Heidi‐Ingrid , Havu Niilo , Sipponen Pentti
Published: March 2003

Background.

A follow‐up of argyrophil cell hyperplasia in Helicobacter pylori‐positive corpus gastritis in gastric ulcer patients during the natural course of ulcer disease.

Methods.

Endoscopic biopsies (4 specimens) were obtained step‐wise from the posterior wall of the corpus mucosa in 55 gastric ulcer (GU) patients. The natural course of GU was followed up in 38 patients during more than 10~years (maximum 19~years), and altogether 115 endoscopic examinations were made: 20 patients were re‐examined once, 14 twice, and 4 three times. A total of 364 biopsies from 307 biopsy sites were stained by Grimelius’ silver, hematoxylin‐eosin, and Giemsa method for the analysis of the argyrophil endocrine cells, chronic gastritis, and H. pylori colonization, respectively, according to the Sydney System.

Results.

Of 307 biopsy sites, 153 (50%) showed some grade of ACH. Focal (linear/micronodular) hyperplasia was found in 118 (77%) of biopsy sites; it was detected in 78 (66%) cases of atrophic corpus mucosa, but was present in only 14 (12%) cases of gastritis without atrophy or in the normal mucosa. In the follow‐up patients, ACH evolved in 17 and progressed in 6 cases, and a simultaneous development of atrophic corpus gastritis was found in 20 cases.

Conclusion.

This study demonstrates that ACH evolves during the natural course of GU, alongside the development of chronic atrophic gastritis.
The Ideal Therapy Must Be Def ined in Each Geographical Area: Experience with a Quadruple Therapy in Spain
Authors: Gomollón F. , Ducóns J.A. , Gimeno L. , Fuentes J. , García S. , Vera J. , Montoro M.
Published: March 2003

Background. Multiple therapeutic combinations have been tested to determine the optimal regimen(s) for Helicobacter pylori eradication, leading to very different results depending on the geographical area. Our goal was to evaluate the efficacy of a “quadruple” therapy with omeprazole, tetracycline, bismuth and metronidazole in our area.

Materials and Methods. We investigate 106 consecutive patients with active peptic ulcer disease (duodenal, gastric or both) and Helicobacter pylori infection. One‐week therapy with omeprazole 20 mg b.i.d., tetracycline hydrochloride 500 mg q.i.d., colloidal bismuth subcitrate 120 mg q.i.d., and metronidazole 250 mg t.i.d was prescribed. Between the days 30 and 40 after treatment ended follow‐up endoscopy was performed. Eradication was defined as both negative urease test and histology. Between days 90 and 360 a 13C urea breath test was performed in 100 patients.

Results. Of the 106 patients in the study, 91 had duodenal ulcer, 12 had gastric ulcer, and 3 had both. Side effects were observed in 25% of the cases. Eradication was achieved in 87.7% (93/106; CI 79.9–93.3). Healing was obtained in 95.2% (100/105; CI 89.2–98.4); 97.8% (CI 92.4–99.7) in those eradicated and 75% (CI 42.8–94.5) in non‐eradicated (p < .01).

Conclusions. Quadruple therapy with omeprazole, tetracycline, bismuth subcitrate and metronidazole achieves healing rates up to 95–100%. The 87.7% eradication rate obtained suggests that the regimen we used is a reasonable therapeutic alternative in our area.
Risk of Gastrointestinal Bleeding Associated with Helicobacter pylori Infection in Patients with Hemophilia or von Willebrand’s Syndrome
Authors: Braden Barbara , Wenke Andrea , Karich Hans‐Joachim , Dietrich Christoph F. , Scharrer Inge , Caspary Wolfgang F. , Lembcke Bernhard
Published: March 2003

Background.

Many episodes of bleeding in the upper gastrointestinal tract are caused by Helicobacter pylori infection. Because these episodes present a life‐threatening complication in patients with bleeding disorders, we prospectively investigated the prevalence of H. pylori infection in patients with hemophilia A or B and with the von Willebrand syndrome.

Methods.

Seventy patients (54 men, 16 women, ages 40 ± 11 years) and 100 age‐related volunteers (63 men, 37 women, ages 39 ± 9 years) were tested for H. pylori infection using the 13C urea breath test. Fifty‐four patients with hemophilia and 16 patients with von Willebrand syndrome participated.

Results.

Thirty‐three (33%) of the controls and 24 (34.3%) of the patients showed positive 13C urea breath tests (p = .97). Nineteen (35.2%) patients with hemophilia and 5 (31.3%) patients with von Willebrand syndrome were positive for H. pylori. History of dyspeptic symptoms (28% vs. 26%) were not different in patients and controls (p = .91). Gastric ulcers (20% vs. 5%) and duodenal ulcers (7% vs. 5%) were diagnosed more often in patients with bleeding disorders. Fourteen of the patients (20%), but none of the controls had a history of gastrointestinal bleeding (p < .001).

Conclusions.

The rate of H. pylori infection and dyspepsia in patients with bleeding disorders is similar to the prevalence in the normal population. Due to increased bleeding complications, H. pylori screening and therapy appears mandatory in patients with bleeding disorders.
Characterization of Helicobacter felis by Pulsed‐Field Gel Electrophoresis, Plasmid Profiling and Ribotyping
Authors: Jalava, Katri , De Ungria, Maria Corazon , O’Rourke, Jani , Lee, Adrian , Hirvi, Urszula , Hänninen Marja‐Liisa
Published: March 2003

Background.

Helicobacter felis, an organism naturally infecting both canine and feline gastric mucosa, has been largely used as in animal models to study the ecology and treatment of human Helicobacter pylori infections. H. felis has not yet been studied at the genetic level.

Methods.

The aims of this study were to modify an in situ DNA isolation method suitable for H. felis and, by the use of pulsed‐field gel electrophoresis (PFGE), plasmid profiling, and ribotyping, to determine the degree of genetic variation among H. felis strains isolated from cats and dogs from various geographic locations, and to determine the genome size of H. felis. Furthermore, the ability of these new H. felis strains to colonize mice was tested.

Results.

Most H. felis strains were distinguishable from each other, and 20 distinct PFGE types were detected. Four pairs of strains within a country and animal species produced identical patterns. All strains tested were found to carry several plasmids and plasmid profiling was equally discriminatory to PFGE. Ribotyping was not able to discriminate all the strains.

Conclusions.

The genome size of H. felis was found to be ≈ 1.6 Mb.
Role of Hpn and NixA of Helicobacter pylori in Susceptibility and Resistance to Bismuth and Other Metal Ions
Authors: Mobley Harry L.T. , Garner Rachel M. , Chippendale Gwynn R. , Gilbert Joanne V. , Kane Anne V. , Plaut Andrew G.
Published: March 2003

Background. Helicobacter pylori produces Hpn, a 60‐amino acid, histidine‐rich protein that avidly binds nickel and zinc ions, and NixA, a high‐affinity nickel transporter in the cytoplasmic membrane. We tested the hypothesis that Hpn and NixA govern susceptibility to metal ions in H. pylori.

Materials and Methods. Hpn‐negative mutants of four H. pylori strains were constructed by standard allelic exchange techniques to yield isogenic Hpn+/Hpn‐deficient pairs. A metal concentration that inhibited growth by 50% (IC50) was calculated for Ni2+, Zn2+, Cu2+, and Co2+ by comparing OD600 of cultures in metal‐supplemented and control media.

Results. Among all four pairs of isogenic strains, the tolerance for Ni2+ was reduced significantly (p < .001) in the Hpn mutants; the mean IC50 value for wild‐type strains was 1.9 mM; for the mutant, it was 0.8 mM. In   contrast, growth inhibition by Zn2+ was identical within the fours pairs, as was Cu2+ and Co2+ tolerance in one pair tested. We also found that deletion of the hpn gene increases susceptibility to therapeutic forms of bismuth by testing a mutant and wild‐type pair with ranitidine bismuth citrate, bismuth citrate, and four antibiotics. Minimal inhibitory concentrations of ranitidine bismuth citrate dropped from 9.2 to 2.3 μg/ml, and those of bismuth citrate dropped from 7.4 to 3.2 μg/ml (p < .05 for both comparisons), while susceptibility to the antibiotics was unaffected. Disruption of the nixA gene encoding the specific Ni2+ transport protein of H. pylori did not change susceptibility to bismuth.

Conclusion. We concluded that bacteria lacking Hpn, cultured in vitro, are more susceptible than is the wild type to bismuth and Ni2+.
Changing Patterns of Helicobacter pylori Gastritis in Long‐Standing Acid Suppression
Authors: Moayyedi Paul , Wason Catriona , Peacock Robert , Walan Anders , Bardhan Karna , Axon Anthony T. R. , Dixon Michael F.
Published: March 2003

Background. Helicobacter pylori colonization and associated inflammation are influenced by local acid output. Infected subjects with acid‐related diseases, such as gastroesophageal reflux disease (GERD) are likely to have an antral‐predominant gastritis. We hypothesized that long‐term acid suppression would result in relatively greater bacterial colonization in the corpus leading to diffuse or corpus‐predominant gastritis and that this would be prevented by prior H. pylori eradication.

Materials and Methods. To investigate this, we conducted a prospective, double‐blind trial of the effect on gastric histology of 12‐month maintenance treatment with omeprazole in H. pylori–positive GERD patients randomly assigned to either an eradication or omeprazole‐alone regime. A control group of 20 H. pylori–negative GERD patients also received omeprazole throughout the study period. Biopsies taken at baseline and at 12 months were graded “blind” by a single observer according to the updated Sydney System. The 41 H. pylori‐positive subjects with grade B or C esophagitis were randomly assigned (20 to omeprazole alone, 21 to eradication) and 33 subjects completed the 12‐month study.

Results. There was a significant decline in antral chronic inflammation in initially positive patients between baseline and end in both the eradication group (p = .035) and the omeprazole‐alone group (p = .008). However, corpus chronic inflammation increased in the omeprazole‐alone group (p = .0156) but decreased in the eradication group. The change toward corpus predominance between baseline and end for the omeprazole‐alone group is highly significant (p = .0078). Furthermore, 5 of 11 in the omeprazole‐alone group developed mild corpus atrophy, compared to 0 of 8 who had undergone H. pylori eradication. The change in frequency of corpus atrophy between the two groups is significant (p = .02).

Conclusion. In H. pylori–positive subjects with GERD, long‐term acid suppression leads to a shift from antral‐ to corpus‐predominant gastritis that can be prevented by prior eradication. The shift is accompanied by an increase in corpus atrophy. H. pylori infection should be eradicated prior to long‐term acid suppression with proton pump inhibitors.
A Possible Relation of the Helicobacter pylori pfr Gene to Iron Deficiency Anemia?
Authors: Choe Yon Ho , Hwang Tae Sook , Kim Hyun Joo , Shin Seok Hwan , Song Sun Uk , Choi Mi Sook
Published: March 2003

Background.

H. pylori infection is thought to contribute to iron‐deficiency anemia, especially during puberty. The ferritin protein Pfr of H. pylori is homologous to eukaryotic and prokaryotic ferritins. The purpose of this study was to analyze the H. pylori pfr status in gastric biopsy specimens according to clinical data, including antral gastritis with or without iron‐deficiency anemia.

Methods.

A total of 26 H. pylori‐positive patients aged from 10–18 years were categorized into subgroups based on the presence or absence of iron‐deficiency anemia. All of them had antral gastritis. Sixteen patients were proved to have iron‐deficiency anemia by hematological study, two of which had a duodenal ulcer. The other 10 patients showed normal hematological findings. DNA isolation was performed from each of the gastric biopsy specimens. PCR amplification of the pfr gene coding was done using two sets of primers. The pfr region, 501 bp, was generated by linking the sequences of the two PCR products. The nucleotide and protein sequences were compared between the pfr regions from Korean H. pylori strains and the NCTC 11638 strain, which was obtained from the Genbank. Sequence comparisons were also performed for the pfr regions between the iron‐deficiency anemia (+) and (−) groups.

Results.

Analysis of the complete coding region of the pfr gene revealed three sites of mutation. The Ser39Ala mutation was found in 100% (26/26), Gly111Asn in 26.9% (7/26), and Gly82Ser in 11.5% (3/26). There were no significant differences in the mutations of the pfr regions between the iron deficiency anemia (+) and (−) groups.

Conclusion.

The mutation in the pfr gene did not relate with the clinical phenotype, iron deficiency anemia. Further studies are needed on the aspects of host side or other complex factors to elucidate the mechanisms by which the H. pylori infection might lead to iron deficiency anemia.
Cell Lysis is Responsible for the Appearance of Extracellular Urease in Helicobacter pylori
Authors: Marcus Elizabeth A. , Scott David R.
Published: March 2003

Background.

Helicobacter pylori is a neutralophilic bacterium that colonizes the acidic human gastric surface using the neutralizing capacity of a constitutively produced urease. Urease is present both in the cytoplasm and bound to the outside surface of the bacteria. The origin of the surface urease continues to be controversial. This study provides additional evidence that the origin of surface urease is cell lysis, not secretion.

Methods.

H. Pylori was transformed with a plasmid encoding green fluorescent protein (GFP), a non‐native cytoplasmic protein. Cultures supplemented with β‐cyclodextrin or horse serum were collected over various time periods and spun through a ficoll cushion to gently separate whole bacteria from released protein. The pellet and supernatant fractions were analyzed by fluorimetry, SDS‐PAGE and Coomassie blue or Western analysis.

Results.

GFP fluorescence and antigenic reactivity in the supernatant increased at each time point. GFP, the non‐native cytoplasmic protein, and UreB, a native cytoplasmic protein, increased over time in the supernatant and both proteins were always present in the pellet fraction. UreI, an inner membrane protein, was only present in the pellet fraction. β‐galactosidase, a protein not found in H. pylori, was used as a negative control.

Conclusions.

Since it is unlikely that there is an intrinsic secretion system for GFP, a non‐native protein, its increasing presence over time in the supernate fraction along with UreB, and retention of UreI in the pellet fraction implies that cell lysis accounts for the presence of urease on the surface of H. pylori.