bluuebunny/crossref_metadata_2025 huggingface dataset:
An improved approach to medical data sets classification: artificial immune recognition system with fuzzy resource allocation mechanism
Authors: Polat Kemal , Güneş Salih
Published: August 2007

Abstract:The artificial immune recognition system (AIRS) has been shown to be an efficient approach to tackling a variety of problems such as machine learning benchmark problems and medical classification problems. In this study, the resource allocation mechanism of AIRS was replaced with a new one based on fuzzy logic. The new system, named Fuzzy‐AIRS, was used as a classifier in the classification of three well‐known medical data sets, the Wisconsin breast cancer data set (WBCD), the Pima Indians diabetes data set and the ECG arrhythmia data set. The performance of the Fuzzy‐AIRS algorithm was tested for classification accuracy, sensitivity and specificity values, confusion matrix, computation time and receiver operating characteristic curves. Also, the AIRS and Fuzzy‐AIRS algorithms were compared with respect to the amount of resources required in the execution of the algorithm. The highest classification accuracy obtained from applying the AIRS and Fuzzy‐AIRS algorithms using 10‐fold cross‐validation was, respectively, 98.53% and 99.00% for classification of WBCD; 79.22% and 84.42% for classification of the Pima Indians diabetes data set; and 100% and 92.86% for classification of the ECG arrhythmia data set. Hence, these results show that Fuzzy‐AIRS can be used as an effective classifier for medical problems.
Artificial intelligence applications in the telecommunications industry
Authors: Qi Jiayin , Wu Feng , Li Ling , Shu Huaying
Published: August 2007

Abstract:Artificial intelligence (AI) has been applied to the telecommunications industry for more than a decade. The purpose of this paper is to examine the application of AI in the telecommunications industry sector. Our research finds that AI's first main application in telecommunications is in the network management area. Expert systems and machine learning are the two AI techniques that have been widely used in telecommunications, while machine learning and distributed artificial intelligence are the two AI techniques which are most promising for the future. The research also finds that different AI techniques have their unique applications in the telecommunications industry.
Search for Correlations Between Genotypes and Electrophysiological Patterns in Migraine: The MTHFR C677T Polymorphism and Visual Evoked Potentials
Authors: Magis D , Allena M , Coppola G , Clemente L Di , Gérard P , Schoenen J
Published: August 2007

Interictally, migraineurs have on average a reduction in habituation of pattern-reversal visual evoked potentials (PR-VEP) and in mitochondrial energy reserve. 5,10-Methylenetetrahydrofolate reductase (MTHFR) is involved in folate metabolism and its C677T polymorphism may be more prevalent in migraine. The aim of this study was to search in migraineurs for a correlation between the MTHFR C677T polymorphism and the PR-VEP profile. PR-VEP were recorded in 52 genotyped migraine patients: 40 female, 24 without (MoA), 28 with aura (MA). Among them 21 had a normal genotype (CC), 18 were heterozygous (CT) and 13 homozygous (TT) for the MTHFR C677T polymorphism. Mean PR-VEP N1-P1 amplitude was significantly lower in CT compared with CC, and tended to be lower in TT with increasing age. The habituation deficit was significantly greater in CC compared with TT subjects. The correlation between the cortical preactivation level, as reflected by the VEP amplitude in the first block of averages, and habituation was stronger in CC than in CT or TT.

The MTHFR C677T polymorphism could thus have an ambiguous role in migraine. On one hand, the better VEP habituation which is associated with its homozygosity, and possibly mediated by homocysteine derivatives increasing serotoninergic transmission, may protect the brain against overstimulation. On the other hand, MTHFR C677T homozygosity is linked to a reduction of grand average VEP amplitude with illness duration, which has been attributed to brain damage.
Cultural capital or relative risk aversion? Two mechanisms for educational inequality compared1
Authors: Van De Werfhorst Herman G. , Hofstede Saskia
Published: August 2007

In this paper we empirically examined two explanatory mechanisms for educational inequality: cultural reproduction and relative risk aversion, using survey data taken from secondary school pupils in Amsterdam. Cultural reproduction theory seeks to explain class variations in schooling by cultural differences between social classes. Relative risk aversion theory argues that educational inequalities can be understood by between‐class variation in the necessity of pursuing education at branching points in order to avoid downward mobility. We showed that class variations in early demonstrated ability are for a substantial part cultural: cultural capital – measured by parental involvement in highbrow culture – affected school performance at the primary and secondary level. However, relative risk aversion – operationalized by being concerned with downward mobility – strongly affects schooling ambitions, whereas cultural capital had no effect. Thus, we conclude that ‘primary effects’ of social origin on schooling outcomes are manifested through cultural capital and not through relative risk aversion (in addition to other potential sources of class variations such as genetics). Relative risk aversion, and not cultural capital, affects schooling ambitions, which is relevant for our understanding of secondary effects.
Death effector activation in the subventricular zone subsequent to perinatal hypoxia/ischemia
Authors: Romanko Michael J. , Zhu Changlian , Bahr Ben A. , Blomgren Klas , Levison Steven W.
Published: August 2007

Perinatal hypoxia/ischemia (H/I) is the leading cause of neurological injury resulting from birth complications and pre‐maturity. Our studies have demonstrated that this injury depletes the subventricular zone (SVZ) of progenitors. In this study, we sought to reveal which cell death pathways are activated within these progenitors after H/I. We found that calpain activity is detected as early as 4 h of reperfusion and is sustained for 48 h, while caspase 3 activation does not occur until 8 h and peaks at 24 h post‐insult. Activated calpains and caspase 3 co‐localized within precursors situated in the lateral aspects of the SVZ (which coincides with progenitor cell death), whereas neither enzyme was activated in the medial SVZ (which harbors the neural stem cells that are resilient to this insult). These studies reveal targets for neuroprotective agents to protect precursors from cell death towards the goal of restoring normal brain development after H/I.
Transcellular biosynthesis of cysteinyl leukotrienes in rat neuronal and glial cells
Authors: Farias Santiago E. , Zarini Simona , Precht Thomas , Murphy Robert C. , Heidenreich Kim A.
Published: August 2007

Leukotrienes are mediators of inflammation that belong to a family of lipids derived from arachidonic acid by the action of 5‐lipoxygenase. Leukotrienes have been detected in the central nervous system in association with different pathological events, but little is known about their biosynthesis or function in the brain. When rat neurons and glial cells in primary culture were stimulated with the calcium ionophore, no significant biosynthesis of leukotrienes was detected using liquid chromatography/mass spectrometry (LC/MS) techniques. However, when exogenous LTA4 was added to these cultured cells, both neurons and glia were able to synthesize LTC4. Activated neutrophils are known to supply LTA4 to other cells for transcellular biosynthesis of cysteinyl‐leukotrienes. Since neutrophils can infiltrate brain tissue after stroke or traumatic brain injury, we examined whether neutrophils play a similar role in the central nervous system. When peripheral blood neutrophils were co‐cultured with rat neurons, glia cells, and then stimulated with calcium ionophore, a robust production of LTC4, LTD4, and LTE4 was observed, revealing that neurons and glia can participate in the transcellular mechanism of leukotriene biosynthesis. The formation of LTC4 through this mechanism may be relevant in the genesis and progression of the inflammatory response as a result of brain injury.
Robust stimulation of TrkB induces delayed increases in BDNF and Arc mRNA expressions in cultured rat cortical neurons via distinct mechanisms
Authors: Yasuda Makoto , Fukuchi Mamoru , Tabuchi Akiko , Kawahara Masahiro , Tsuneki Hiroshi , Azuma Yuko , Chiba Yusuke , Tsuda Masaaki
Published: August 2007

In cultures of rat cortical neurons, we found that stimulation of tyrosine receptor kinase B (TrkB) with brain‐derived neurotrophic factor (BDNF) induced a biphasic expression of BDNF exon IV–IX mRNA, which became obvious 1–3 h (primary induction) and 24–72 h (delayed induction) after the stimulation, and characterized the delayed induction in relation to the mRNA expression of activity‐regulated cytoskeleton‐associated protein (Arc). Withdrawal of BDNF from the medium after stimulation for 3 h allowed the delayed induction, which was caused at the transcriptional level and dependent upon the initial contact between exogenously added BDNF and TrkB, the effect of which was time‐ and dose‐dependent. The primary induction was controlled by the extracellular signal‐regulated kinase/mitogen‐activated protein kinase (ERK/MAPK) whereas the secondary induction by the calcium (Ca2+) signaling pathway. The enhanced Arc or Zif268 mRNA expression was controlled by activation of the ERK/MAPK pathway, both of which were repressed by blocking the binding of endogenously synthesized BDNF to TrkB. Thus, robust stimulation of TrkB autonomously induces delayed BDNF mRNA expression in an activity‐dependent manner in rat cortical neurons, resulting in the stimulation of Arc mRNA expression through endogenously synthesized BDNF, the process being orchestrated by the Ca2+ and ERK/MAPK signaling pathways.
PERMANENT GENETIC RESOURCES: Polymorphic microsatellite loci for Diachasma alloeum (Hymenoptera: Braconidae)
Authors: FORBES ANDREW A. , POWELL THOMAS H. Q. , LOBO NEIL F. , NOOR MOHAMED A. F. , FEDER JEFFREY L.
Published: August 2007

Here, we report the isolation of 21 novel primers for amplification of microsatellite loci in Diachasma alloeum (Hymenoptera: Braconidae). Diachasma alloeum is a larval parasitoid of the apple maggot fly (Rhagoletis pomonella), which is an economically significant agricultural pest species and a textbook example of sympatric speciation via host‐plant shifting. These microsatellite markers will prove useful both for assessing genetic relationships between different host‐associated populations of D. alloeum, as well as for future R. pomonella biological control programmes. We also report the cross‐species amplification of several loci for Diachasmimorpha mellea and Diachasma ferrugineum, parasitoids of R. pomonella and R. cingulata, respectively.
PERMANENT GENETIC RESOURCES: Development of microsatellite markers for two nonviviparous mangrove species, Acanthus ilicifolius and Lumnitzera racemosa
Authors: GENG Q. F. , LIAN C. L. , TAO J. M. , HOGETSU T.
Published: August 2007

Eight and nine of microsatellite loci were isolated from two nonviviparous mangrove species, Acanthus ilicifolius and Lumnitzera racemosa, respectively. The number of alleles per locus ranged from two to eight in A. ilicifolius and two to nine in L. racemosa. The observed heterozygosities ranged from 0.200 to 0.875 in A. ilicifolius and from 0.025 to 0.350 in L. racemosa. These loci would be effective for analysing genetic diversity and population genetic structure of these two mangrove species.
Monovision: a review
Authors: Evans Bruce J. W.
Published: August 2007

In presbyopia, patients can no longer obtain clear vision at distance and near. Monovision is a method of correcting presbyopia where one eye is focussed for distance vision and the other for near. Monovision is a fairly common method of correcting presbyopia with contact lenses and has received renewed interest with the increase in refractive surgery. The present paper is a review of the literature on monovision. The success rate of monovision in adapted contact lens wearers is 59–67%. The main limitations are problems with suppressing the blurred image when driving at night and the need for a third focal length, for example with computer screens at intermediate distances. Stereopsis is impaired in monovision, but most patients do not seem to notice this. These limitations highlight the need to take account of occupational factors. Monovision could cause a binocular vision anomaly to decompensate, so the pre‐fitting screening should include an assessment of orthoptic function. Various methods have been used to determine which eye should be given the distance vision contact lens and the literature on tests of ocular dominance is reviewed. It is concluded that tests of blur suppression are most likely to be relevant, but that ocular dominance is not fixed but is rather a fluid, adaptive, phenomenon in most patients. Suitable patients can often be given trial lenses that allow them to experiment with monovision in real world situations and this can be a useful way of revealing the preferred eye for each distance. Of course, no patient should drive or operate machinery until successfully adapted to monovision. Surgically induced monovision is less easily reversed than contact lens‐induced monovision, and is only appropriate after a successful trial of monovision with contact lenses.
Technical Note: Dimensionless ray transference
Authors: Misson G. P. , Harris W. F. , Cardoso J. R. , Van Gool R. D.
Published: August 2007

The ray transference matrix completely characterises the first‐order optical nature of an optical system including the eye. It is in terms of the transference that quantitative analyses (for example, calculation of an average eye) can be performed. However, the fact that the entries of the transference do not have the same physical dimensions precludes the calculation of the usual scalar value (a Frobenius norm for example) for a change or difference between two optical systems. The purpose of this note is to show how to use the wavelength of the light as a natural unit of length to define a dimensionless transference and so make it possible to calculate a meaningful norm. In most practical applications, some components of the dimensionless transference may dominate unreasonably in the resulting norm in which case suitably weighted norms may be more appropriate. In an appendix, some of the issues are illustrated by application to a lens.
Mapping of error cells in clinical measure to symmetric power space
Authors: Abelman H. , Abelman S.
Published: August 2007

During the refraction procedure, the power of the nearest equivalent sphere lens, known as the scalar power, is conserved within upper and lower bounds in the sphere (and cylinder) lens powers. Bounds are brought closer together while keeping the circle of least confusion on the retina. The sphere and cylinder powers and changes in these powers are thus dependent. Changes are depicted in the cylinder–sphere plane by error cells with one pair of parallel sides of negative gradient and the other pair aligned with the graph axis of cylinder power. Scalar power constitutes a vector space, is a meaningful ophthalmic quantity and is represented by the semi‐trace of the dioptric power matrix. The purpose of this article is to map to error cells for the following: coordinates of the dioptric power matrix, its principal powers and meridians and its entries from error cells surrounding powers in sphere, cylinder and axis. Error cells in clinical measure for conserved scalar power now contain more compensatory lens powers. Such cells and their respective mappings in terms of most scientific and alternate clinical quantities now image consistently not only to the cells from where they originate but also to each other.
A survey of the availability of state‐funded primary eye care in the UK for the very young and very old
Authors: Shah Rakhee , Evans Bruce J. W. , Edgar David
Published: August 2007

Background:  The National Health Service (NHS) provides General Ophthalmic Services (GOS) to eligible patients in the UK. Nearly all community optical practices have a contract with the NHS via local primary care organisations (primary care trusts in England) allowing the practices to provide NHS sight tests to eligible patients.

Objective:  To determine the accessibility of GOS sight tests for certain groups of patient in the UK.

Method:  A telephone survey was carried out to investigate the availability of GOS sight tests for two categories of eligible patient. A total of 200 primary eye care practices were randomly selected, of which 100 were telephoned to establish the availability of a sight test for a child aged 1 year whose mother is concerned due to the presence of a family history (parental) of strabismus. The other 100 practices were telephoned to investigate the availability of a sight test for a person aged 90 years who was described as having dementia.

Results:  A total of 199 of the 200 practices provided GOS sight tests. The mean age at which practices declared that they start examining children was 3.1 years. Most (76%) practices recommended an eye examination for the 1‐year‐old child, but only 46% said that they would carry this out themselves. Of the other 100 practices telephoned across the country, 93% said that they could arrange an eye examination for the patient with dementia.

Discussion:  Of the UK optical practices that participated in this study, 99.5% provide GOS sight tests. About half of these would not offer a GOS sight test to a 1‐year‐old child. It has been suggested that the GOS Terms of Service do not permit practitioners to exclude categories of patients from GOS services, although we argue that this interpretation is equivocal. Indeed, it is suggested that clinical and ethical reasons may sometimes require practitioners to decline to examine certain categories of patient. It is worrying that one quarter of practices did not recommend an eye examination for a young child with a family history of strabismus. It is hoped that a continuing education and training project will increase interest in paediatric optometry.
Technical Note: A comparison of central and peripheral intraocular pressure using rebound tonometry
Authors: Queirós A. , González‐Méijome J. M. , Fernandes P. , Jorge J. , Montés‐Micó R. , Almeida J. B. , Parafita M. A.
Published: August 2007

Purpose:  To compare central and peripheral intraocular pressure (IOP) readings obtained with rebound tonometry.

Methods:  Intraocular pressure was measured on the right eye of 153 patients (65 males, 88 females), aged from 21 to 85 years (mean ± S.D., 55.5 ± 15.2 years) with the ICare rebound tonometer at centre, and 2 mm from the limbus (in the nasal and temporal regions along the 0–180º corneal meridian).

Results:  Intraocular pressure values obtained with the ICare were 14.9 ± 2.8; 14.1 ± 2.5 and 14.5 ± 2.7 mmHg at centre, nasal and temporal corneal locations, respectively. On average, nasal and temporal IOP readings were 0.75 and 0.37 mmHg lower than the central reading (p < 0.05 and p > 0.05, respectively). A highly significant correlation was found between central and peripheral measurements in nasal (r2 = 0.905; p < 0.001) and temporal (r2 = 0.879; p < 0.001) regions along the horizontal meridian. Almost 80% of patients presented nasal IOP values within ±1 mmHg of the central value.

Conclusions:  Intraocular pressure values measured with the ICare® rebound tonometer on the nasal corneal region is slightly lower on average and highly correlated with IOP values recorded at corneal centre. Both nasal and temporal readings are in good agreement with central IOP, and could be used to obtain a reliable estimate of rebound IOP in corneas where central readings cannot be taken.
Run‐off transport of herbicides during natural and simulated rainfall and its reduction by vegetated filter strips
Authors: Pätzold S. , Klein C. , Brümmer G. W.
Published: August 2007

The efficiency of filter strips in protecting watercourses against herbicides in run‐off was evaluated in field experiments in western Germany. Surface run‐off caused by natural rainfall and related transport of metolachlor, terbuthylazine and pendimethalin were measured on plots of 40 m length without filter strips (F0), and after passing over three types of herbicide‐untreated field margin: 12 m conservation headland (CH12), 6 m (GF6) and 12 m grass strips (GF12). Run‐off was also measured after simulated rainfall on 7 m long plots without (F0) and with 3 m grass strips (GF3). All three herbicides were transported both in dissolved and in adsorbed forms; the partitioning depended on their water solubility with metolachlor and terbuthylazine mainly translocated in dissolved form (F0: highest mean concentrations for a natural run‐off event 721 and 220 μg L−1, respectively). Pendimethalin was predominantly transported in adsorbed form (maximum mean concentration 11.2 μg L−1). In the sediment, the highest mean herbicide contents in a single natural event (F0) accounted for 2294 μg kg−1 (metolachlor), 1317 μg kg−1 (terbuthylazine) and 5648 μg kg−1 (pendimethalin). The proportions of applied herbicide translocated were 0.3% (metolachlor), 0.2% (terbuthylazine) and 0.06% (pendimethalin; F0, natural rainfall). The extent of herbicide transport decreased with time but within this trend soil sealing, soil moisture and amount and intensity of rainfall increased losses. Compared with the F0 plots, the reduction of herbicide translocation after natural rainfall reached 80–83% (CH12), 80–88% (GF6) and >99% (GF12) over the 3‐year period. The 12 m grass strips allowed only one extreme run‐off event to pass through, thus providing a highly effective watercourse protection against herbicide pollution.
Effectiveness of palm and simulated geotextiles in reducing run‐off and inter‐rill erosion on medium and steep slopes
Authors: Smets T. , Poesen J. , Fullen M. A. , Booth C. A.
Published: August 2007

Palm‐leaf geotextiles could be an effective and cheap soil conservation method with enormous global potential. However, there are very few data on the effectiveness of palm geotextiles in reducing soil erosion by water. This study investigates the effectiveness of two types of palm geotextiles and the effect of geotextile mesh size on infiltration, run‐off and inter‐rill erosion rate and soil surface roughness on a medium and steep slope. A well‐defined protocol was developed to conduct laboratory experiments. Rainfall was simulated for 90 min with an intensity (I) of 45 and 67 mm h−1 on an inter‐rill erosion plot, filled with an erodible sandy loam and having slope gradients (S) of 15 and 45%. Two palm‐leaf geotextiles (Borassus aethiopum and Brazilian Buriti Palm) and three simulated geotextiles (polyethylene tarpaulin) with different mesh sizes (1 × 1, 5 × 5 and 12 × 12 cm) were tested on a simulated fine tilth. Calculated k values from the Horton infiltration equation ranged from 0.025 to 0.145 and decreased linearly on both slopes with geotextile cover. Geotextiles are more effective in reducing the run‐off coefficient on a medium slope (15%) compared with that on a steep slope (45%), ranging from 76.4 to 17.9%. Mean b values from the mulch cover equation equalled 0.024 for a 15% slope and 0.045 for a 45% slope, indicating a higher effectiveness of geotextiles in reducing total inter‐rill soil loss on gentler slopes compared with commonly used mulches. Erosion‐induced soil surface roughness at the end of each experiment increased linearly with geotextile cover percentage and this increase was not significantly different between the two slope gradients.
Bracken effects on inorganic nitrogen leaching from an upland podzol
Authors: Smart R. P. , Calver L. J. , Crowe A. M. , Emmerson K. M. , Cresser M. S.
Published: August 2007

Leaching of inorganic N species to stream waters from upland areas of the UK is increasing, reflecting the increases in atmospheric deposition of nitrogen species due to increased levels of vehicular emissions. Bracken cover in UK uplands is also increasing overall (Taylor, 1986), and the architectural nature of bracken has been shown to both increase deposition of atmospheric constituents to soils and change their chemical and physical nature. We have tested the nutrient status of upland podzols from the Lake District, Cumbria, UK, from under both moorland grass and bracken. The results show reduced levels of base cations and nitrate throughout the profile and decreases in the organic matter content of surface horizons as a consequence of bracken encroachment. We also report increased ammonium concentrations in lower soil horizons under bracken, possibly leading to increased leaching to stream waters. These results suggest either increased leaching of soil nutrients due to bracken encroachment or increased storage of nutrients within the bracken rhizome system. Results also suggest changes in either microbial activity or the microbial community of podzols, possibly due to the allelopathic nature of bracken. This may have caused changes in the soil nutrient dynamics, possibly accounting for some of the changes seen. We hypothesize that increased bracken cover within the British uplands has the potential to increase leaching of inorganic nitrogen to upland streams.
Impact of Intangible Capital on Productivity and Growth: Lessons from the Indian Information Technology Software Industry*
Authors: DE SUPRIYO , DUTTA DILIP
Published: August 2007

This paper examines the impact of intangible capital, including human capital and organisational capabilities on productivity, using India as an illustrative example. The research breaks new ground in creating measures of intangible capital at a micro level. Measures of tangible and intangible capital are used to estimate a ‘new economy’ production function with panel data. Generalised method of moments techniques are used to account for unobserved firm heterogeneity and endogenous explanatory variables. The results indicate that intangible assets have a major impact on software sector output. This has important implications for public policy and corporate strategy towards the information technology industry, including for Australia.
Birth Centers in Australia: A National Population‐Based Study of Perinatal Mortality Associated with Giving Birth in a Birth Center
Authors: Tracy Sally K , Dahlen Hannah , Caplice Shea , Laws Paula , Wang Yueping Alex , Tracy Mark B. , Sullivan Elizabeth
Published: August 2007

ABSTRACT:  Background:
Perinatal mortality is a rare outcome among babies born at term in developed countries after normal uncomplicated pregnancies; consequently, the numbers involved in large databases of routinely collected statistics provide a meaningful evaluation of these uncommon events. The National Perinatal Data Collection records the place of birth and information on the outcomes of pregnancy and childbirth for all women who give birth each year in Australia. Our objective was to describe the perinatal mortality associated with giving birth in “alongside hospital” birth centers in Australia during 1999 to 2002 using nationally collected data.
Methods:
This population‐based study included all 1,001,249 women who gave birth in Australia during 1999 to 2002. Of these women, 21,800 (2.18%) gave birth in a birth center. Selected perinatal outcomes (including stillbirths and neonatal deaths) were described for the 4‐year study period separately for first‐time mothers and for women having a second or subsequent birth. A further comparison was made between deaths of low‐risk term babies born in hospitals compared with deaths of term babies born in birth centers.
Results:
The total perinatal death rate attributed to birth centers was significantly lower than that attributed to hospitals (1.51/1,000 vs 10.03/1,000). The perinatal mortality rate among term births to primiparas in birth centers compared with term births among low‐risk primiparas in hospitals was 1.4 versus 1.9 per 1,000; the perinatal mortality rate among term births to multiparas in birth centers compared with term births among low‐risk multiparas in hospitals was 0.6 versus 1.6 per 1,000.
Conclusions:
This study using Australian national data showed that the overall rate of perinatal mortality was lower in alongside hospital birth centers than in hospitals irrespective of the mother’s parity. (BIRTH 34:3 September 2007)
Hospital Practices that Increase Breastfeeding Duration: Results from a Population‐Based Study
Authors: Murray Erin K. , Ricketts Sue , Dellaport Jennifer
Published: August 2007

ABSTRACT:  Background:
A high percentage (83%) of mothers in Colorado initiate breastfeeding; but in keeping with national breastfeeding trends, many of them discontinue breastfeeding within the first few months. The objective of this study was to determine the effects of hospital practices on breastfeeding duration and whether the effects differed based on maternal socioeconomic status.
Methods:
Pregnancy Risk Assessment Monitoring System data were used to calculate breastfeeding duration rates for all Colorado mothers in 2002 to 2003. Breastfeeding duration rates were determined for recipients of each of nine hospital practices included in the survey compared with rates for nonrecipients. Practices that significantly increased breastfeeding duration rates were combined and then stratified by socioeconomic status.
Results:
Breastfeeding duration was significantly improved when mothers experienced all five specific hospital practices: breastfeeding within the first hour, breastmilk only, infant rooming‐in, no pacifier use, and receipt of a telephone number for use after discharge. Two‐thirds (68%; 95% CI: 61–75) of mothers who experienced all five successful practices were still breastfeeding at 16 weeks compared with one‐half (53%; 95% CI: 49–56) of those who did not. Breastfeeding duration was improved independent of maternal socioeconomic status. Only one in five mothers (18.7%) experienced all five supportive hospital practices. Mothers who experienced the five supportive hospital practices were significantly less likely to stop breastfeeding due to any of the top reasons given for stopping (p < 0.001). Conclusions: Implementation of the five hospital practices supportive of breastfeeding significantly increased breastfeeding duration rates regardless of maternal socioeconomic status. (BIRTH 34:3 September 2007)
Female Relatives or Friends Trained as Labor Doulas: Outcomes at 6 to 8 Weeks Postpartum
Authors: Campbell Della , Scott Kathryn D , Klaus Marshall H , Falk Michele
Published: August 2007

ABSTRACT:  Background:
Data collected on more than 12,000 women in 15 randomized controlled trials provide robust evidence of the beneficial effects of doula support on medical outcomes to childbirth. The objective of this paper was to examine the association between doula support and maternal perceptions of the infant, self, and support from others at 6 to 8 weeks postpartum. The doula was a minimally trained close female relative or friend.
Methods:
Six hundred low‐risk, nulliparous women were enrolled in the original clinical trial and randomized to doula support (n = 300) or standard care (n = 300). The mother‐to‐be and her doula attended two 2‐hour classes about providing nonmedical, continuous support to laboring women. For the secondary study, presented here, research participants (N = 494) were interviewed by telephone using a 42‐item questionnaire. Results: Overall, when doula‐supported mothers (n = 229) were compared with mothers who received standard care (n = 265), they were more likely to report positive prenatal expectations about childbirth and positive perceptions of their infants, support from others, and self‐worth. Doula‐supported mothers were also most likely to have breastfed and to have been very satisfied with the care they received at the hospital. Conclusions: Labor support by a minimally trained female friend or relative, selected by the mother‐to‐be, enhances the postpartum well‐being of nulliparous mothers and their infants, and is a low‐cost alternative to professional doulas. (BIRTH 34:3 September 2007)
Does Cesarean Section Reduce Postpartum Urinary Incontinence? A Systematic Review
Authors: Press Joshua Z , Klein Michael C , Kaczorowski Janusz , Liston Robert M. , Von Dadelszen Peter
Published: August 2007

ABSTRACT:  Background:
The impact of delivery mode on the development of urinary incontinence has been much debated. The primary objective of this systematic review was to compare the prevalence of postpartum urinary incontinence after cesarean section compared with vaginal birth.
Methods:
The MEDLINE (1966–2005) and CINAHL (1982–2005) databases were searched for reports specifying postpartum prevalence or incidence of unspecified, stress, urge, and mixed urinary incontinence by mode of birth. Primary authors were contacted to request unpublished data about severity, parity, and timing of cesarean section. All data were entered into Review Manager software, and odds ratio (OR), absolute risk reduction, and number needed to prevent were calculated.
Results:
Cesarean section reduced the risk of postpartum stress urinary incontinence from 16 to 9.8 percent (OR = 0.56 [0.45, 0.68], number needed to prevent = 15 [12,22]) in 6 cross‐sectional studies, and from 22 to 10 percent in 12 cohort studies (OR=0.48 [0.39, 0.58], number needed to prevent = 10 [8,13]). Differences persisted by parity and after exclusion of instrumental delivery, but risk of severe stress urinary incontinence and urge urinary incontinence did not differ by mode of birth. Conclusions: Although short‐term occurrence of any degree of postpartum stress urinary incontinence is reduced with cesarean section, severe symptoms are equivalent by mode of birth. Risk of postpartum stress urinary incontinence must be considered in the context of associated maternal and newborn morbidity and mortality. (BIRTH 34:3 September 2007)
Information and Informed Consent for Neonatal Screening: Opinions and Preferences of Parents
Authors: Detmar Symone , Hosli Esther , Dijkstra Nynke , Nijsingh Niels , Rijnders Marlies , Verweij Marcel
Published: August 2007

ABSTRACT:  Background:
The current neonatal screening program (“the heel prick”) involves taking a few drops of blood from almost every newborn in the Netherlands to determine whether the child is suffering from one of three congenital disorders: phenylketonuria, congenital hypothyroid, or adrenogenital syndrome. This study investigated the preferences and views of parents and future parents with respect to information about, and consent to, neonatal screening and the possible expansion of the program.
Methods:
Seven focus group discussions took place with future parents, parents with a healthy child, and parents with children affected by disorders for which screening is possible, now or in the future (total of 36 participants). The discussions were audiotaped, transcribed, and analyzed for content.
Results:
Parents were not well informed about what the heel prick involves at present. Nevertheless, they see it as a routine procedure and do not think about the possibility of refusing it. If the heel‐prick program were to be expanded, parents would like to be informed earlier, preferably during pregnancy. In addition, most parents preferred an opt‐out consent approach.
Conclusions:
If the neonatal screening program is to be expanded, parents would prefer for information about the program be given during pregnancy. In addition, they preferred an opt‐out consent approach, on condition that screening was for the purpose of preventing irreversible harm. Parental opinion was divided on this issue if the aim of screening were to be widened. (BIRTH 34:3 September 2007)
Thoughts and Emotions During Traumatic Birth: A Qualitative Study
Authors: Ayers Susan
Published: August 2007

ABSTRACT:  Background:
Previous research shows that 1 to 6 percent of women will develop symptoms of posttraumatic stress disorder after childbirth. The objective of this study was to examine thoughts and emotions during birth, cognitive processing after birth, and memories of birth that might be important in the development of postnatal posttraumatic stress symptoms.
Methods:
In a qualitative study, women with posttraumatic stress symptoms (n= 25) and without (n = 25) were matched for obstetric events to examine the nonmedical aspects of birth that made it traumatic. Women were interviewed 3 months after birth. Results: The following themes emerged for all women: thoughts during birth included mental coping strategies, wanting labor to end, poor understanding of what was going on, and mental defeat. More negative than positive emotions were described during birth, primarily feeling scared, frightened, and upset. Postnatal cognitive processing included retrospective appraisal of birth, such as taking a fatalistic view and focusing on the present, for example, concentrating on the baby. Memories of birth included not remembering parts of the birth and forgetting how bad it was. Women with posttraumatic stress symptoms reported more panic, anger, thoughts of death, mental defeat, and dissociation during birth; after birth, they reported fewer strategies that focused on the present, more painful memories, intrusive memories, and rumination, than women without symptoms. Conclusions: The results provide a useful first step toward identifying aspects of birth and postnatal processing that might determine whether women develop postnatal posttraumatic stress symptoms. Further research is needed to broaden knowledge of posttraumatic stress disorder before drawing definite conclusions (BIRTH 34:3 September 2007)
The Patient‐Centered (R)Evolution
Authors: Klein Michael C. , Enkin Murray W. , Kotaska Andrew , Shields Sara G.
Published: August 2007

PREFACE:  This “In the Literature” column has a different genesis from previous columns. It emanates from a discussion that began on the Maternity Care Discussion Group (MCDG), an online group of more than 600 family physicians, obstetricians, midwives, nurses, and doulas that has been hosted on the College of Family Physicians of Canada website for 20 years. Although mainly a Canadian list, international participants are welcome to join in the struggle to improve maternity care and support those who provide it. To join the MCDG List, send an e‐mail to mklein@interchange.ubc.ca.
L‐Lactic Acid Secreted from Gastric Mucosal Cells Enhances Growth of Helicobacter pylori
Authors: Takahashi Tetsufumi , Matsumoto Tsukasa , Nakamura Masahiko , Matsui Hidenori , Tsuchimoto Kanji , Yamada Haruki
Published: August 2007

Background:  Helicobacter pylori mainly inhabit the mucus layer in the gastric mucosa. However, mechanisms involving H. pylori colonization and proliferation in gastric mucosa are not well established. This study focuses on elucidating the role of gastric mucosal cells on growth of H. pylori.

Materials and methods:  H. pylori was co‐cultured with the murine gastric surface mucosal cells (GSM06), and the growth of H. pylori on the cells was assessed by enumerating the colony‐forming units (CFU). The H. pylori growth factor in the culture media conditioned by GSM06 cell was purified by HPLC, and the chemical structure of the growth factor was identified by analyses of 1H‐ and 13C‐NMR spectra.

Results:  A marked increase in the number of CFU of H. pylori was observed in the GSM06 cells. The enhanced H. pylori growth was also observed when indirectly incubated with GSM06 cells through semi‐permeable membrane. In addition, culture media conditioned by GSM06 cell stimulated H. pylori growth approximately one thousand‐fold. By bioassay‐guided purification, the H. pylori growth factor was isolated from the conditioned medium of GSM06 cells and identified as l‐lactic acid. The H. pylori growth‐enhancing activity under microaerobic condition was well correlated with l‐lactic acid concentrations in the conditioned media.

Conclusions:  This study demonstrates that l‐lactic acid secreted by gastric mucosal cells enhances the growth of H. pylori, and this l‐lactic acid‐dependent growth of H. pylori may be important to the long‐term colonization of H. pylori in the stomach.
Helicobacter pylori Inflammation, Immunity, and Vaccines
Authors: D’Elios Mario Milco , Andersen Leif P.
Published: August 2007

Helicobacter pylori infects almost 50% of the world population and is the major cause of gastroduodenal diseases. H. pylori colonizes the gastric mucosa, activates Toll‐like and Nod‐like receptors, and usually elicits a T helper 1 (Th1) type of immune response, fully polarized in peptic ulcer patients. Among several bacterial factors, the neutrophil‐activating protein represents a key factor driving Th1 inflammation. A complex and fascinating balance between H. pylori and host factors takes part in the gastric niche and allows the majority of infected individuals to be without any symptom during their entire life. Novel insights into the innate and adaptive responses against H. pylori, dealing with regulatory T cells and cytokines, CTLA‐4 molecule, cholesterol glucosylation, and immune evasion have been elucidated during the past year and are discussed for the development of an effective vaccine.
Extragastric Manifestations of Helicobacter pylori Infection – Other Helicobacters
Authors: Bohr Ulrich R. M. , Annibale Bruno , Franceschi Francesco , Roccarina Davide , Gasbarrini Antonio
Published: August 2007

Today there is evidence that Helicobacter pylori has a critical role in different extragastric diseases. The discovery of a number of other novel Helicobacter species has stimulated the research in different extragastric diseases, in which an infectious hypothesis is plausible. Enterohepatic Helicobacter species have been hypothesized to play a role in different disorders, including hepatocellular carcinoma, gallstones formation and cholangiocellular carcinoma, as well as enteric diseases and inflammatory bowel diseases. Concerning the extragastric manifestations of H. pylori infection, idiopathic thrombocytopenic purpura, and sideropenic anemia represent, based on the current data, the diseases in which the pathogenic link appears to be strongest. There is also an increasing evidence for a possible association of H. pylori with cardiovascular disease.
Cross‐Primed CD8+ Cytotoxic T cells Induce Severe Helicobacter‐associated Gastritis in the Absence of CD4+ T cells
Authors: Fukui Toshiro , Nishio Akiyoshi , Okazaki Kazuichi , Kasahara Katsuhiro , Saga Kazuyuki , Tanaka Junya , Uza Norimitsu , Ueno Satoru , Kido Masahiro , Ohashi Shinya , Asada Masanori , Nakase Hiroshi , Watanabe Norihiko , Chiba Tsutomu
Published: August 2007

Background:  Although previous studies have reported important roles of CD4+ type1‐helper T cells and regulatory T cells in Helicobacter‐associated gastritis, the significance of CD8+ cytotoxic T cells remains unknown. To study the roles of CD8+ T cells, we examined the immune response in the gastric mucosa of Helicobacter felis‐infected major histocompatibility complex (MHC) class II‐deficient (II−/–) mice, which lack CD4+ T cells.

Materials and methods:  Stomachs from H. felis‐infected wild‐type and infected MHC II−/– mice were examined histologically and immunohistochemically. Gastric acidity and serum levels of anti‐H. felis antibodies were measured. The expression of pro‐inflammatory and anti‐inflammatory cytokine, Fas‐ligand, perforin, and Foxp3 genes in the gastric mucosa was investigated.

Results:  H. felis‐infected MHC II−/– mice developed severe gastritis, accompanied by marked infiltration of CD8+ cells. At 1 and 2 months after inoculation, mucosal inflammation and atrophy were more severe in MHC II−/– mice, although gastritis had reached similar advanced stages at 3 months after inoculation. There was little infiltration of CD4+ cells, and no Foxp3‐positive cells were detected in the gastric mucosa of the infected MHC II−/– mice. The expression of the interleukin‐1β and Fas‐ligand genes was up regulated, but that of Foxp3 was down regulated in the infected MHC II−/– mice. Serum levels of anti‐H. felis antibodies were lower in the infected MHC II−/– mice, despite severe gastritis.

Conclusions:  The present study suggests that cross‐primed CD8+ cytotoxic T cells can induce severe H.‐associated gastritis in the absence of CD4+ helper T cells and that Foxp3‐positive cells may have an important role in the control of gastric inflammation.
Anticonvulsant Effects of Carbamazepine on Spontaneous Seizures in Rats with Kainate‐induced Epilepsy: Comparison of Intraperitoneal Injections with Drug‐in‐food Protocols
Authors: Grabenstatter Heidi L. , Clark Suzanne , Dudek F. Edward
Published: August 2007

Summary

Purpose: The present study evaluated the effectiveness of intraperitoneal (IP) injections and oral administration of carbamazepine (CBZ) in food on the frequency of spontaneous motor seizures in rats with kainate‐induced epilepsy. The purpose was to develop a convenient drug‐in‐food approach for continuous, long‐term administration of potential antiepileptic drugs (AEDs).

Methods: Single IP injections of CBZ (10–100 mg/kg) were compared to vehicle injections via six AED‐versus‐vehicle tests using a repeated‐measures, crossover protocol. Similar protocols were used with CBZ‐containing or control food pellets.

Results: CBZ significantly reduced motor seizure frequency at 30 and 100 mg/kg after single IP injections, and these doses completely blocked motor seizures during a 6‐h postdrug epoch in 25% and 70% of the animals, respectively. Single administrations of 30 mg/kg and 100 mg/kg CBZ in food also significantly reduced motor seizures, and blocked seizures in 33% and 89% of the rats, respectively. CBZ administered in food three times per day (100 mg/kg ×3 CBZ in food) continuously blocked nearly all motor seizures over a 5‐day period, and completely suppressed motor seizures in 50% of the animals tested.

Conclusions: CBZ strongly suppresses spontaneous motor seizures, and single doses of CBZ in food are as effective as IP injections in rats with kainate‐induced epilepsy. CBZ administered regularly in food continuously blocks nearly all motor seizures, and may provide a relatively simple method to test AEDs in chronic models of epilepsy.
A Case with Atypical Childhood Occipital Epilepsy “Gastaut Type”: An Ictal Migraine Manifestation with a Good Response to Intravenous Diazepam
Authors: Parisi Pasquale , Kasteleijn‐Nolst Trenité Dorothée GA , Piccioli Marta , Pelliccia Andrea , Luchetti Anna , Buttinelli Carla , Villa Maria Pia
Published: August 2007

Summary

We report the history of a 14‐year‐old girl with atypical childhood occipital epilepsy “Gastaut type” whose first generalized tonic–clonic seizure was preceded by migraine without aura and followed by a status migrainosus. This status lasted for 3 days despite standard analgesic therapy. An EEG recording revealed an occipital status epilepticus during her migraine complaints. Seven minutes after intravenous administration of 10 mg diazepam under continuous EEG recording, a suppression of the epileptiform discharges over the right occipital was seen, while the headache subsided 3 min later. After precise questioning about the circumstances that possibly could have led to these events, it appeared that she had played for hours with a play station on the new color TV and she had visited an exhibition of Matisse and Bonnard with bright colors and contrast‐rich text. Standardized extensive intermittent photic stimulation (IPS), 2 days after the status migrainosus, evoked besides asymmetrical right‐sided driving, green spots in her left visual field, while in the EEG sharp waves were recorded over the right parietotemporal region. After further IPS with 20 Hz (eye closure), she started complaining of a light pulsating headache right occipitally and in the EEG right parietotemporal sharp‐waves were seen. This lasted for about 10 min. Later, an interictal routine EEG was normal except for some theta over the right temporooccipital area. The most likely diagnosis is an atypical form of occipital epilepsy “Gastaut type.” We would therefore advocate recording EEGs with photic stimulation in patients with atypical migraneous features.