bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sphingosine modulation of cAMP levels and beating rate in rat heart
Authors: Benediktsdóttir V. Edda , Jónsdóttir Anna M. , Skúladóttir Bergthóra H. , Grynberg Alain , Skarphéðinsson Jón Ó. , Helgason Jóhannes , Gudbjarnason Sigmundur 
Published: March 2003

AbstractSphingolipids, especially as elements of the sphingomyelin signal transduction cycle, are thought to play a significant role as second messengers and modulators of events in heart muscle cells. A possible modulatory role of sphingosine in signal transduction in the β‐adrenergic pathway in the heart was examined. Neonatal rat cardiomyocytes were incubated with sphingosine and/or other agents after which cAMP levels and contraction rates were measured. Heart rate in anaesthetized rats was also measured before and after sphingosine injection in the jugular vein. Sphingosine caused a decrease in basal cAMP levels and diminished isoproterenol‐induced increase in cAMP levels. These changes were dose‐ and time‐dependent and showed a significant negative effect on signal transmission in the β‐adrenergic pathway in cardiomyocytes. Increase in cAMP intracellular levels by forskolin, which activates adenylcyclase, was not inhibited by sphingosine. A phosphodiesterase inhibitor was used in all experiments in which cAMP was measured excluding effects on cAMP breakdown. It was also demonstrated that sphingosine caused reduction in the beating rate of cultured cardiomyocytes and a dose‐dependent reduction in heart rate of anaesthetized rats. The sphingosine‐induced inhibition of bradycardic response of anaesthetized rats reached a maximum about 5–10 min after the onset of sphingosine administration and returned to normal within 60 min. Sphingosine may modulate the signal transmission of the β‐adrenoceptor pathway upstream of adenylcyclase in rat cardiomyocytes. This may contribute to the sphingosine‐induced decrease in heart rate of rats in vivo.
Cardiac baroreflex control in humans during and immediately after brief exposure to simulated high altitude
Authors: Roche Frédéric , Reynaud Claire , Garet Martin , Pichot Vincent , Costes Frédéric , Barthélémy Jean‐Claude 
Published: March 2003

SummaryTo examine the baroreflex response in humans during and immediately after acute hypoxia exposure, the cardiac baroreflex sensitivity (BRS) was studied using adaptation of RR intervals in response to spontaneous systolic blood pressure fluctuations (sequences methodology) in 11 unacclimatized subjects. All measurements were made under fixed breathing rate, and realized consecutively at baseline level (20 min), at an inspired oxygen concentration of 11% (15 min) and again under normoxic conditions (20 min; recovery period). The spontaneous baroreflex response decreases progressively during hypoxic exposure, causing a tachycardic response at this FiO2 without any significant alteration of the systolic or diastolic blood pressure. The magnitude of decrease for this variable at the end of exposure averaged 42·9 ± 15·6%. The simultaneous spectral analysis of heart rate (HR) variability in hypoxic condition confirmed an alteration in the parasympathetic activity (HFnu: −17·8 ± 30·9% versus basal conditions, P<0·01) counterbalanced by an exaggerated sympathetic activity (LFnu: +33 ± 42·4%, P<0·05) at the sinus node. Interestingly, we could observe an enhanced cardiac baroreflex response during the period following the inhalation of the hypoxic mixture (+130·6 ± 15·6% of basal conditions, P<0·001). There is a relationship with a significant and abrupt increase in the parasympathetic control of HR (mean HR reached 111 ± 8·1% of the mean basal HR, P<0·01). These results suggest that brief exposure to hypoxia under rate‐controlled ventilation is associated with a significant alteration in the spontaneous cardiac baroreflex. This important cardiac autonomic imbalance is followed by a significant increase in the cardiac parasympathetic drive even after the disappearance of the hypoxic stimulus.
Historical and Contemporary Maternal Population Structuring in the Endangered Hastings River Mouse (Pseudomys oralis)
Authors: Jerry Dean R. , Dow Tanya A. , Elphinstone Martin S. , Baverstock Peter R. 
Published: March 2003

The Hastings River mouse (Pseudomys oralis) is a small, endangered Australian conilurine rodent. Only about 200 specimens of this rodent have ever been caught, and little is known about its biology. At present, populations of this species appear to be severely fragmented. We used temperature‐gradient gel electrophoresis and DNA sequencing to investigate maternal population structuring in this species and to determine if the pattern of fragmentation is the consequence of anthropogenic influences. Based on a 345 bp section of the mitochondrial control region, all sample localities were found to be genetically distinct, with only 1 haplotype out of 11 found present in more than one sample locale. Phylogenetic reconstructions from sequence data clustered haplotypes into two distinct clades, demonstrating that contemporary population structure in the Hastings River mouse has a historical component. The discovery that populations of the Hastings River mouse are not only currently genetically isolated but have been separated for long periods of evolutionary time has clear management ramifications for the conservation of this species. In particular, each population should now be treated as demographically independent and administered as a separate management unit. Estructura Histórica y Contemporánea de la Población Materna de el Ratón del Rio Hastings (Pseudomys oralis) en Peligro de Extinción. El ratón del río Hastings (Pseudomys oralis) es un roedor australiano pequeño en peligro de extinción. Unicamente 200 especímenes de este roedor han sido capturados y se conoce muy poco de su biologia. Actualmente, las poblaciones de esta especie aparentan estar severamente fragmentadas. Utilizamos gel electroforésis de gradiente de temperatura y secuenciado de ADN para investigar la estructura poblacional materna en la especie y para examinar si los patrones de fragmentación son consecuencia de influencias antropogénicas. Basados en secciones de 345 bp de la region de control mitocondrial, todas las muestras fueron encontradas genéticamente distintas, con un haplotipo de once encontrados presente en mas de una muestra. Reconstrucciones filogenéticas de datos de secuencias agrupó haplotipos en dos grupos distintivos, demostrando que poblaciones contemporáneas del raton del río Hastings tiene un componente histórico. El descubrimiento de que poblaciones del ratón del río Hastings no estan solo aisladas genéticamente en la actualidad, sino que han estado separadas por largos períodos de tiempo evolucionario tiene ramificaciones claras de manejo para la conservación de esta especie. En particular, cada población deberá ser tratada ahora como demográficamente independiente y administrada como una unidad de manejo separada.
A National Survey of Use of Obstetric Procedures and Technologies in Canadian Hospitals: Routine or Based on Existing Evidence?
Authors: Kaczorowski Janusz , Levitt Cheryl , Hanvey Louise , Avard Denise , Chance Graham 
Published: March 2003

Background:The objective of this national survey was to describe the routine use of procedures and technologies in Canadian hospitals providing maternity care, and to determine the extent to which current use was consistent with the existing evidence and recommended guidelines for maternal and newborn care.Methods:Representatives of 572 hospitals providing maternity care across Canada were sent questionnaires in the spring and summer of 1993; 523 (91.4%) responded. The primary outcome measures consisted of the self‐reported use of obstetric procedures and technologies (perineal shaves, enemas/suppositories, intravenous infusions, initial and continuous electronic fetal heart monitoring, episiotomy rates). Hospitals were grouped according to location, size (number of live births per year), and university affiliation status.Results:The hospitals in the Prairie provinces, in Quebec, and in the Atlantic provinces were significantly less likely than those in Ontario to restrict their use of perineal shaves and enemas to women on admission in labor. Small hospitals were significantly more likely than large hospitals (> 1000 live births) to restrict their use of intravenous infusions, and initial and continuous electronic fetal monitoring. The university‐affiliated and nonteaching hospitals were significantly less likely than the university teaching hospitals to have episiotomy rates of less than 40 percent for primiparous women. Small hospitals were more likely than large hospitals to report episiotomy rates of less than 20 percent for multiparous women.Conclusions:Considerable variations occur in the routine use of obstetric procedures and technologies in Canadian hospitals providing maternity care, according to hospital location, size, and university affiliation status. Despite the existing evidence suggesting that the routine use of these practices and procedures is both unnecessary and potentially harmful, a significant number of Canadian hospitals continued to use them routinely in 1993. (BIRTH 25:1, March 1998)
SELECTED COCHRANE SYSTEMATIC REVIEWS Absorbable Synthetic Versus Catgut Suture Material for Perineal Repair
Authors: Kettle C. , Johanson R.B. 
Published: March 2003

A substantive amendment to this systematic review was last made on 19 May 1999. Cochrane reviews are regularly checked and updated if necessary.ABSTRACT Background and objectives: Approximately 70% of women will experience some degree of perineal trauma following vaginal delivery and will require stitches. This may result in perineal pain and superficial dyspareunia. The objective of this review was to assess the effects of absorbable synthetic suture material as compared with catgut on the amount of short‐ and long‐term pain experienced by mothers following perineal repair. Search strategy: We searched the Cochrane Pregnancy and Childbirth Group trials register. Selection criteria: Randomised trials comparing absorbable synthetic (polyglycolic acid and polyglactin) with plain or chromic catgut suture for perineal repair in mothers after vaginal delivery. Data collection and analysis: Trial quality was assessed independently by two reviewers. Data were extracted by one reviewer and checked by the second reviewer. Main results: Eight trials were included. Compared with catgut, the polyglycolic acid and polyglactin groups were associated with less pain in first three days (odds ratio 0.62, 95% confidence interval 0.54–0.71). There was also less need for analgesia (odds ratio 0,63, 95% confidence interval 0.52–0.77) and less suture dehiscence (odds ratio 0.45, 95% confidence interval 0.29–0.70). There was no significant difference in long‐term pain (odds ratio 0.81, 95% confidence interval 0.61–1.08). Removal of suture material was significantly more common in the polyglycolic acid and polyglactin groups (odds ratio 2.01, 95% confidence interval 1.56–2.58). There was no difference in the amount of dyspareunia experienced by women. Reviewers' conclusions: Absorbable synthetic suture material (in the form of polyglycolic acid and polyglactin sutures) for perineal repair following childbirth appears to decrease women's experience of short‐term pain. The length of time taken for the synthetic material to be absorbed is of concern. A trial addressing the use of polyglactin has recently been completed and this has been included in this updated review. Citation: Kettle C, Johanson RB. Absorbable synthetic versus catgut suture material for perineal repair (Cochrane Review). In: The Cochrane Library, Issue 4, 1999, Oxford: Update Software.••• The preceding report is an abstract of regularly updated, systematic reviews prepared and maintained by the Cochrane Collaboration. The full texts of the reviews are available in The Cochrane Library (ISSN 1464‐780X). See
http://www.update‐software.com/cochrane.htm
or contact Update Software,
info@update.co.uk, for information on subscribing to The Cochrane Library in your area. Update Software Ltd, Summertown Pavilion, Middle Way, Oxford OX2 7LG, United Kingdom (Tel.: +44 1865 513902; Fax: +44 1865 516918).
Experiences of Fears Associated with Pregnancy and Childbirth: A Study of 329 Pregnant Women
Authors: Hanna‐Leena Melender RM 
Published: March 2003

Background:  Women may experience a variety of fears in association with pregnancy and childbirth. The purpose of this study was to describe their objects, causes, and manifestations, and to identify factors associated with the fears.Methods: The study sample comprised 481 pregnant women in western Finland, of whom 329 (response rate 69%) completed a questionnaire. It was developed on the basis of semi‐structured interviews and previous studies and had a 4‐point scale and a dichotomous scale. Data were subjected to rotated factor analysis, and sum variables were produced. The effects of various demographic variables were calculated using the Kruskal‐Wallis and Mann‐Whitney U tests.Results: Of the 329 respondents, 78 percent expressed fears relating to pregnancy, to childbirth, or to both. Specific fears concerned childbirth, the child's and mother's well‐being, health care staff, family life, and cesarean section. Causes of fears were negative mood, negative stories told by others, alarming information, diseases and child‐related problems, and, in multiparas, negative experiences of previous pregnancy, childbirth, and baby's health and care; causes were significantly related to occupation. Fears were manifested as symptoms of stress, effects on everyday life, and a wish to have a cesarean section or to avoid pregnancy and childbirth; employment situation and elective cesarean section were the most important factors related to manifestation of fears. Parity and antenatal training were the most important variables related to objects of fears.Conclusions: Women's fears that are associated with pregnancy and childbirth can be explained by different factors. It is important for perinatal health caregivers to ask pregnant women about their feelings related to the current pregnancy, childbirth, and future motherhood, and to give women who express fears an opportunity to discuss them, paying special attention to primiparas and to multiparas with negative experiences of earlier pregnancies. (BIRTH 29:2 June 2002)
Does Birth Center Care During a Woman's First Pregnancy Have Any Impact on Her Future Reproduction?
Authors: Gottvall Karin , Waldenström Ulla 
Published: March 2003

ABSTRACT: Background: Women's experiences of childbirth may affect their future reproduction, and the model of care affects their experiences, suggesting that a causal link may exist between model of care and future reproduction. The study objective was to examine whether the birth center model of care during a woman's first pregnancy affects whether or not she has a second baby, and on the spacing to the next birth.Methods: Between October 1989 and July 1993, a total of 1860 women at low medical risk in early pregnancy, who participated in a randomized controlled trial of in‐hospital birth center care versus standard care, gave birth. The 1063 primiparas in the trial, 543 in the birth center group and 520 in the standard care group, were included in a secondary analysis in which women's personal identification codes were linked to the Swedish National Birth Register, which included information about their subsequent birth during the following 7 to10 years. Time to an event curves were constructed by means of the Kaplan Meier method.Results: The observation period after the first birth was on average 8.8 years in the birth center group and 8.7 years in the standard care group. No statistical difference was found between the groups in time to second birth, which was 2.85 and 2.82 years, respectively (median; log‐rank 1.26; p=0.26).Conclusion: A woman's model of care, such as birth center care, during her first pregnancy does not seem to be a sufficiently important factor to affect subsequent reproduction in Sweden. (BIRTH 29:3 September 2002)
Quadruple Therapy Is Effective for Eradicating Helicobacter pylori After Failure of Triple Proton‐Pump Inhibitor–Based Therapy: A Detailed, Prospective Analysis of 21 Consecutive Cases
Authors: Gomollón Fernando , Ducóns J.A. , Ferrero M. , Cabezudo J. García , Guirao R. , Simón M.A. , Montoro M. 
Published: March 2003

Background. Data regarding the effectiveness of second‐line treatment of Helicobacter pylori infection are limited, especially if microbiological studies are considered.Methods and Patients. We conducted a prospective, uncontrolled study of a consecutive series of 21 peptic ulcer patients with failure of 1‐week lansoprazole, amoxicillin, and clarithromycin. H. pylori status was evaluated by urease test, histology, culture, and urea breath test. Susceptibility to amoxicillin, clarithromycin, and metronidazole was studied by E‐test. Cure of infection was defined as negative results from endoscopy‐based tests 1 month after treatment and negative results from a urea breath test at 2 months. Treatment consisted of a 1‐week combination of lansoprazole (30 mg bid), tetracycline (500 mg qid), metronidazole (500 mg tid), and bismuth subcitrate (120 mg qid).Results. H. pylori was resistant to metronidazole in three cases, to clarithromycin in three cases, and to both clarithromycin and metroinidazole in an additional three patients. No resistance to amoxicillin was found. Eradication was obtained in 20 cases (95.2% confidence interval [CI], 76.2–99.9). The only patient in whom infection was not eradicated harbored a metronidazole‐resistant (minimum inhibitory concentration> 32 μg/ml) strain. No significant side effects were reported.Conclusion. Quadruple therapy obtains a high eradication rate even in patients with clarithromycin‐ and metronidazole‐resistant strains. Further randomized and controlled studies are warranted and are urgently needed.
Addition of Metronidazole to Rabeprazole‐Amoxicillin‐Clarithromycin Regimen for Helicobacter pylori Infection Provides an Excellent Cure Rate with Five‐Day Therapy
Authors: Nagahara Akihito , Miwa Hiroto , Ogawa Kaoru , Kurosawa Akihiko , Ohkura Ryuichi , Iida Noboru , Sato Nobuhiro 
Published: March 2003

Background. New triple therapy for eradication of Helicobacter pylori based on a proton pump inhibitor (PPI) provides a cure rate of approximately 90% with few adverse effects. Recently, a PPI‐based quadruple therapy, which consists of a PPI plus bismuth‐based triple therapy for 7 days, has been studied, and a sufficient eradication rate has been achieved. However, a shorter duration results in improved compliance. In this study, newly developed short‐term, simple twice‐daily quadruple therapy consisting of rabeprazole, amoxicillin, clarithromycin, and metronidazole (RACM) was compared with a PPI‐based triple‐therapy regimen for eradication of H. pylori.Patients and Methods. This study was designed as a randomized open, prospective single‐center study. Of a total of 105 H. pylori–positive patients, 55 received the RACM regimen for 5 days (rabeprazole, 10 mg bid; amoxicillin, 750 mg bid; clarithromycin, 200 mg bid; and metronidazole, 250 mg bid), and 50 received the RAC regimen for 5 days (rabeprazole, 10 mg bid; amoxicillin, 750 mg bid; and clarithromycin, 200 mg bid). Cure of the infection was assessed by HpSA (H. pylori stool antigen immunoassay) 1 month after completion of therapy.Results. The rates of eradication of H. pylori by RACM versus RAC were 94.5% (95% CI, 85–99) versus 80.0% (95% CI, 66–90) by intention‐to‐treat analysis; 98.1% (95% CI, 90–100) versus 87.0% (95% CI, 74–95) by all‐patients‐treated analysis; and 98.1% (95% CI, 90–100) versus 86.7% (95% CI, 73–95) by per‐protocol analysis. No major adverse effects were reported, and 98.0% of patients reported complete compliance.Conclusions. The simple twice‐daily and short‐term quadruple regimen for only 5 days provided an excellent eradication rate. Compliance with the regimen was high, and serious adverse effects were few. Therefore, the RACM regimen can be considered as safe and effective.
Identif ication of Enterohepatic Helicobacter Species by Restriction Fragment‐Length Polymorphism Analysis of the 16S rRNA Gene
Authors: Shen Zeli , Feng Yan , Fox James G. 
Published: March 2003

Background. Restriction fragment‐length polymorphism (RFLP) analysis of a 1,200‐bp polymerase chain reaction–amplified DNA fragment of gene coding for 16S rRNA was used to generate restriction profiles of 11 enterohepatic Helicobacter spp. isolated from various animals and humans.Methods. The amplicon from each Helicobacter sp. was digested with four restriction endonucleases: Alu I, Hinf I, Hha I, and Dde I. Alu I digestion produced five patterns that were useful for initial differentiation.Results. Most Helicobacter spp. isolated from rodents had the same RFLP profiles by Alu I digestion (except H. rodentium and H. cholecystus), but they had different RFLP profiles by Hha I digestion. Only H. bilis and “H. rappini” mouse isolates could not be readily distinguished by the polymerase chain reaction‐RFLP method. However, these two species can be distinguished using H. bilis specific primers. Some of the Helicobacter spp. have an intervening sequence in their 16S rRNA gene, which changes the RFLP patterns; in these cases, sequencing is the preferred method to make an appropriate diagnosis.Conclusions. The RFLP method used in this study was straightforward and rapid and should prove useful as an adjunct for identification and classification of multiple enterohepatic Helicobacter spp.
Helicobacter pylori Induces Apoptosis in Human Epithelial Gastric Cells by Stress Activated Protein Kinase Pathway
Authors: Domek Matthew J. , Netzer Peter , Prins Bruce , Nguyen Trang , Liang Dan , Wyle Frederic A. , Warner Alberta 
Published: March 2003

AbstractBackground.The pathway by which Helicobacter pylori induces apoptosis in gastric epithelial cells is not known. The aim of this study was to determine whether H. pylori‐induced apoptosis is associated with SAPK/JNK activity in human gastric cancer KATO III cells.Materials and Methods. H. pylori VacA toxin positive strain was incubated with KATO III cells for 0.5, 1, 2 or 24 hours. The SAPK/JNK protein was harvested from the KATO III cell lysate by precipitation with a C‐jun fusion protein and its activity was measured by C‐jun phosphorylation utilizing transblotting and phosphoserine antibody. Cellular apoptosis was demonstrated by DNA fragmentation. In addition, cell growth in coculture with H. pylori was determined over 72 hours.Results. H. pylori significantly stimulated SAPK/JNK activity in KATO III cells with a peak at the 0.5 hour time point (3.6‐fold vs. control, p < .05), but a return to basal levels by 2 hours. In addition, significant DNA fragmentation was observed after 24 hours in these cells but not in the control KATO III cells. Cell growth was inhibited in a dose dependent fashion in coculture with H. pylori.Conclusion.These results show that H. pylori triggers an increase in apoptosis in KATO III cells as reflected by DNA fragmentation. This effect was preceded and correlated with an increase in SAPK/JNK activity suggesting that the H. pylori‐induced apoptosis in human gastric epithelial cells may be mediated by the SAPK/JNK pathway.