bluuebunny/crossref_metadata_2025 huggingface dataset:
Chromosome 1p and 19q status and p53 and p16 expression patterns as prognostic indicators of oligodendroglial tumors: A clinicopathological study using fluorescence in situ hybridization
Authors: Jeon Yoon Kyung , Park Kyeongmee , Park Chul Ki , Paek Sun Ha , Jung Hee Won , Park Sung‐Hye
Published: January 2007

To verify the prognostic implications of the statuses of chromosome 1p and 19q and the expressions of p53, p16 and GFAP in oligodendrogliomas, we investigated these parameters and correlated the results with patient outcome. Twenty‐seven cases of low‐grade oligodendroglioma (LO) and 29 cases of anaplastic oligodendroglioma (AO) were analyzed by FISH for 1p and 19q status and by immunohistochemistry for p53, p16, and GFAP expression using a tissue microarray. Direct sequencing of the p53 gene was also performed. 1p deletion was observed in 39 of 56 patients (69.9%), and 19q deletion in 41 of 56 (73.2%). Combined loss of 1p and 19q was found in 38 of 56 (67.9%) and exhibited distinct concomitant deletion (P = 0.000). p53 overexpression was observed in 17 cases (30.3%), GFAP expression in 18 cases (32.1%), and p16 loss in 40 cases (74%) of oligodendrogliomas. The expressions of p53 and GFAP were more frequent in AO than in LO (P = 0.015 and 0.001). In contrast, p53 expression was more common in oligodendrogliomas with an intact 19q (P = 0.029), or an intact 1p (P = 0.071). Only five of 14 patients with p53 expression showed TP53 mutation, which was inversely correlated with 1p deletion (P = 0.036). Patients with combined loss of 1p and 19q exhibited better overall survival (P = 0.045). Patients with p53 expression without combined 1p and 19q loss showed poor overall survival (P < 0.000). However, TP53 mutation along with 1p and 19q status could not predict patient outcome. Patients with p16 loss without combined 1p and 9q loss showed poor overall survival (P = 0.011). Therefore, in oligodendrogliomas, the absence of the combined deletion of 1p and 19q and the aberrant expression of p53 or loss of p16 could be used as poor prognostic markers.
Apoptotic phenomena are not a major cause of enteric neuronal loss in constipated patients with dementia
Authors: Bassotti Gabrio , Villanacci Vincenzo , Fisogni Simona , Cadei Morris , Di Fabio Francesco , Salerni Bruno
Published: January 2007

Chronic constipation is a frequent symptom in patients with dementia, especially in those institutionalized. However, few data are available on the neuropathological aspects of the colon in such patients. We investigated the enteric neuropathology of the colon in two patients with longstanding dementia and intractable constipation, requiring surgery to alleviate symptoms. The results were compared to those obtained in 10 controls. No abnormalities were found at conventional histological examination, except for the presence of melanosis coli. Immunohistochemical evaluation revealed no important difference between patients and controls, except for a decreased number of enteric neurons in patients. However, this neuronal decrease was not associated to apoptotic phenomena, as observed in patients with severe idiopathic constipation. We concluded that in severely constipated patients with dementia the neuropathological abnormalities might be reconducted to a physiological neuronal decrease as a result of aging, and that the pathophysiological aspects of constipation in these subjects differ from those found in idiopathic constipation.
Frontotemporal dementia and parkinsonism linked to chromosome 17 with the N279K tau mutation
Authors: Slowinski Jerzy , Dominik Jake , Uitti Ryan J. , Ahmed Zeshan , Dickson Dennis D. , Wszolek Zbigniew K.
Published: January 2007

We present a case of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP‐17) harboring the N279K mutation in the MAPT gene from the family known as pallido‐ponto‐nigral degeneration (PPND). This 49‐year‐old man was followed for 17 years. He presented at age 41 years with left leg stiffness and en‐bloc turning. During the course of his illness he developed a constellation of symptoms including parkinsonism, pyramidal signs, vertical gaze palsy, dysphagia, dystonia, personality and cognitive dysfunction, weight loss and mutism. Gross neuropathological examination showed mild atrophy of the cerebral cortex, hippocampal formation, amygdala, thalamus, subthalamic nucleus and depigmentation of the substantia nigra. Microscopy revealed neuronal loss and gliosis in the same regions. Tau immunohistochemistry showed pretangles, numerous threads, grain‐like structures and oligodendroglial tau‐positive inclusions (“coiled bodies”). In the spinal cord the tau pathology was more abundant in gray than white matter. Pretangles and threads were present in the anterior and, to a lesser extent, in the posterior horns. FTDP‐17 should be suspected in patients with a history of familial parkinsonism combined with behavioral and cognitive changes, onset before age 65 years and an aggressive clinical course.
Pre‐morbid morphological conditions of the human pituitary
Authors: Rittierodt Marion , Hori Akira
Published: January 2007

The clinically silent premorbid conditions of the pituitary, in particular preneoplastic features, were morphologically and statistically investigated within a control population at autopsy. A higher percentage of premorbid states were found, which was speculated to be a basis of possible later clinical lesions. They were as follows in 228 pituitary specimens: incidentalomas in 3% (potential pituitary adenomas), aberrant salivary gland cell clusters in the pars intermedia in 8.8% (potential salivary gland cysts or carcinomas in the sellar region), residual Rathke’s cleft cells in 3.2–6.8% (potential craniopharyngiomas), meningothelial aggregates in the pituitary capsule in 4.0% (potential meningiomas), one case also had ciliated epithelial cell fragments in the anterior lobe, one case each of granular cell and nerve cell group in the posterior lobe, and two cases of telangiectasia. Furthermore, aberrant anterior pituitary cells were found in the leptomeniges of the peri‐pituitary region as a possible basis of an intracranial ectopic pituitary adenoma. Silent premorbid conditions were not infrequently found (up to 8.8%). In particular, the “basis” of the possible neoplasm was pre‐existent, so that some triggers are necessary (e.g., pituitary tumor transforming gene, hormonal stimuli, etc.) for it to become manifest, although there was no direct morphological evidence in our findings to alter to the lesions.
The effect of videotaped preoperative information on parental anxiety during anesthesia induction for elective pediatric procedures
Authors: McEWEN ANDREW , MOORTHY CLAIRE , QUANTOCK CHRISTOPHER , ROSE HANNAH , KAVANAGH RICHARD
Published: January 2007

Background:  The purpose of this study was to determine whether audiovisual information, describing the process of undergoing and recovering from anesthesia, could reduce anxiety levels in parents before their child's induction of anesthesia.

Methods:  One hundred and eleven parents were recruited into this study. Of these 56 were randomized to a control group and 55 to an intervention group. All parents completed the Amsterdam Preoperative Anxiety and Information Scale (APAIS) questionnaires on admission to hospital on the day of surgery and then again just before accompanying their child to the anesthetic room. In addition to the normal preoperative preparation, parents randomized into the study group watched a short 8‐min information video after completing the first questionnaire. The video illustrated the events and procedures surrounding a child's admission to hospital for day‐case surgery, including the induction of anesthesia.

Results:  The results were analyzed using repeated measures of anova. There was a statistically significant reduction in anxiety and desire for information in the intervention group compared with the control group (P < 0.05).

Conclusions:  The reduction in anxiety in the intervention group indicates that preoperative information videos are an effective method of reducing anxiety in parents. Furthermore, the reduction in need for information score in the intervention group indicates that preoperative videos may be a useful tool for providing parents with information.
Continuous positive airway pressure and lung separation during cardiopulmonary bypass to facilitate congenital heart surgery via the right thorax in children
Authors: MITTNACHT ALEXANDER J.C. , JOASHI UMESH , NGUYEN KHANH , CHIN CYNTHIA , SRIVASTAVA SHUBHIKA , HOLLINGER INGRID
Published: January 2007

We describe a fast track anesthesia technique that facilitates congenital heart surgery via right axillary thoracotomy in children. Continuous positive airway pressure on the dependent lung, before and during cardiopulmonary bypass, approximates the heart towards the chest wall incision, and significantly improves the surgeon's access to the heart.
INTERTEMPORAL OPTIMIZING MODELS OF TRADE AND CURRENT ACCOUNT BALANCE: A SURVEY
Authors: Singh Tarlok
Published: January 2007

Abstract This study surveys the intertemporal optimizing models of trade and current account balance that were developed, calibrated and empirically tested since they came into vogue in the 1980s. The implications of these models often differ from those of static and dynamic conventional non‐optimizing models. The literature on optimizing models has not only grown reasonably fast, but has also witnessed significant advances in methodology, and these models have culminated into a distinct strand of new open‐economy macroeconomics. The studies conducted until the late 1980s have used deterministic perfect‐foresight models, while several studies conducted since the 1990s relax the perfect‐foresight and certainty equivalence assumptions and develop stochastic dynamic general equilibrium models to account for uncertainty confronting the optimizing agents. The future research needs to explore the possibility of tracing any preferred specification of household preferences, model the effect of time‐varying discount factor on household utility function and intertemporal budget constraint, examine the role of costs in international trade, place a parallel emphasis on the empirical verifications of theoretical propositions, examine the relative performance of optimizing vis‐à‐vis non‐optimizing models and rationalize the extreme propositions of perfect and imperfect capital mobility in the wake of moderately open capital accounts.
A Social Proximity Explanation of the Reluctance to Assimilate
Authors: Fan C. Simon , Stark Oded
Published: January 2007

The pursuit of migration is an extreme example of the severing of ties with, or a distancing from, one's friends and home. The ‘failure’ of migrants to assimilate cannot plausibly be attributed merely to an urge to stay close to their friends, or they might not have migrated to begin with. Non‐assimilation arises from a fear of enhanced relative deprivation if they reduce their distance from the natives as a reference group. Fundamentally, migration is a change of those with whom people associate. But it would be wrong to infer that a change of associates crowds out a change of behavior, given the associates. Through their actions, migrants can elect to associate more with some groups, less with others. However, when actions to keep in check the weight accorded to the rich natives as a reference group are not viable, the very choice of migration destination could be affected in an unexpected way: a country that is not so rich could be preferable to a country that is rich; migrants will protect themselves from an unfavorable comparison by not migrating to where the comparison, when unavoidable, would be highly unfavorable. Relatedly, the variance in the assimilation effort of migrants across host countries could arise from the variance in the income distance with the natives: the richer the natives, the weaker the effort to assimilate, other things held the same.
Fractionalization and Inter‐Group Differences
Authors: Lind Jo Thori
Published: January 2007

Fractionalization has been shown to have a detrimental effect on growth, public goods provision, and redistribution. The conventional measure of fractionalization is the Herfindahl index, which calculates the probability that two persons drawn at random belong to different groups. This measure implicitly assumes that all groups are equally distant. In this paper, I argue that a more appropriate measure of fractionalization should take into account that some groups are more different than others, so we need a measure of groups distance. We should then measure fractionalization as the average distance between every citizen, or equivalently the average distance between groups weighted by group size. I present a simple method to estimate these distances from opinion survey data by regressing stated opinions on indicator variables from group and a set of control variables. The coefficients on the group variables can then be interpreted as measures of distance. Finally, I apply the method to US data and show that we get more reasonable measures of fractionalization.
The Impact of Liberalizing Barriers to Foreign Direct Investment in Services: The Case of Russian Accession to the World Trade Organization
Authors: Jensen Jesper , Rutherford Thomas , Tarr David
Published: January 2007

In this paper a computable general equilibrium model of the Russian economy is used to assess the impact of accession to the World Trade Organization (WTO), which encompasses improved market access, Russian tariff reduction, and reduction of barriers against multinational service providers. It is assumed that foreign direct investment in business services is necessary for multinationals to compete well with Russian business services providers, but cross‐border service provision is also present. The model incorporates productivity effects in both goods and services markets endogenously, through a Dixit–Stiglitz framework. It is estimated that Russia will gain about 7.2% of the value of Russian consumption in the medium term from WTO accession and up to 24% in the long run. It is also estimated that the largest gains to Russia will derive from liberalization of barriers against multinational service providers. Piecemeal and systematic sensitivity analysis shows that the results are robust.
Cohort Sampling Schemes for the Mantel–Haenszel Estimator
Authors: GOLDSTEIN LARRY , LANGHOLZ BRYAN
Published: January 2007

Abstract.  In many epidemiological studies, disease occurrences and their rates are naturally modelled by counting processes and their intensities, allowing an analysis based on martingale methods. Applied to the Mantel–Haenszel estimator, these methods lend themselves to the analysis of general control selection sampling designs and the accommodation of time‐varying exposures.
Estimating the Upper Support Point in Deconvolution
Authors: AARTS LUCIE , GROENEBOOM PIET , JONGBLOED GEURT
Published: January 2007

Abstract.  We consider estimation of the upper boundary point F−1 (1) of a distribution function F with finite upper boundary or ‘frontier’ in deconvolution problems, primarily focusing on deconvolution models where the noise density is decreasing on the positive halfline. Our estimates are based on the (non‐parametric) maximum likelihood estimator (MLE) of F. We show that (1) is asymptotically never too small. If the convolution kernel has bounded support the estimator (1) can generally be expected to be consistent. In this case, we establish a relation between the extreme value index of F and the rate of convergence of (1) to the upper support point for the ‘boxcar’ deconvolution model. If the convolution density has unbounded support, (1) can be expected to overestimate the upper support point. We define consistent estimators , for appropriately chosen vanishing sequences (βn) and study these in a particular case.
Model Comparison for a Complex Ecological System
Authors: Ferguson C. A. , Bowman A. W. , Scott E. M. , Carvalho L.
Published: January 2007

The ecological consequences of climate change and its interaction with other environmental pressures, such as nutrient pollution, are little understood. For freshwater ecosystems, knowledge of these combined effects is required for water resource management and in particular for successful implementation of the European Community Water Framework Directive 2000, which requires that all surface-waters should be at, or above, ‘good status’ by 2016. Statistical analysis of detailed long-term environmental data sets can be used to explore these combined effects. Loch Leven (Scotland) has been routinely monitored since 1967, providing one of the largest and most extensive of such data sets. Over this period there has been evidence of climate change and a period of eutrophication and recovery at the loch. Transfer functions, additive models and varying-coefficient models are used to explore the complex ecological system at Loch Leven with the aim of obtaining insight into the combined effects of climate change and eutrophication on water quality.
Does Neck Pain Determine the Outcome of Adolescent Headache?
Authors: Laimi K , Vahlberg T , Salminen JJ , Metsähonkala L , Mikkelsson M , Anttila P , Aromaa M , Sillanpää M
Published: January 2007

The aim of the study was to examine the influence of concomitant neck pain (NP) on the outcome of headache (HA) frequency and HA type in adolescence. A population-based sample of 13-year-olds with or without HA ( n = 228) was followed for 3 years. NP was evaluated at the beginning of the follow-up on the basis of recorded muscle tenderness and self-reported symptoms. During the 3 years of follow-up, changes in both HA type and frequency were common. NP interfering with daily activities at the age of 13 years predicted change from non-frequent (0-1/month) to monthly HA (>1/month), especially in boys ( P = 0.03 boys, P = 0.06 girls). The use of physiotherapy predicted persistence of monthly HA in boys ( P = 0.004). The changes in HA type were not predictable by NP. In conclusion, the risk of worsening HA in adolescence is more probable if the HA is associated with NP interfering with daily activities.
Combined Effects of ACE and MMP-3 Polymorphisms On Migraine Development
Authors: Kara I , Ozkok E , Aydin M , Orhan N , Cetinkaya Y , Gencer M , Kilic G , Tireli H
Published: January 2007

Migraine is a primary headache disorder which involves both genetic and environmental components. Since angiotensin-converting enzyme (ACE) and matrix metalloproteinase (MMP) share the same homology, we investigated whether the MMP-3 and ACE I/D gene variants are involved in migraine risk and whether the ACE variant might act in combination with the MMP-3 genetic variant in patients with migraine. This is the first study to evaluate the association between MMP-3 and ACE polymorphisms, and migraine. Genotypes were determined by polymerase chain reaction. The frequencies of 5A5A genotypes of the MMP-3 and D allele of ACE were significantly elevated, but II genotypes of the ACE and 6A allele of MMP-3 significantly decreased in all patients. The combined DD/5A5A and ID/5A5A genotypes increased the risk of migraine. Individuals who were homozygous for the deletion (D) allele showed increased ACE activity. Subjects with the 5A5A genotype and/or D allele or with the combined DD/5A5A or ID/5A5A might be more susceptible to migraine development. In contrast, subjects with the II and/or 6A6A genotypes may be protected from migraine development. The greater activity of the 5A5A and DD genotypes might result in vascular reactivity that is more pronounced in migraine. Taken together, our data suggest that numerous genes may influence ACE activity. Discovery of new genes might better clarify the pathogenesis of migraine and open an avenue to therapeutic strategies against migraine.
Headache and Recurrent Abdominal Pain: A Controlled Study by the Means Of The Child Behaviour Checklist (CBCL)
Authors: Galli F , D'Antuono G , Tarantino S , Viviano F , Borrelli O , Chirumbolo A , Cucchiara S , Guidetti V
Published: January 2007

Headache and recurrent abdominal pain (RAP) are common disorders in children and adolescents, frequently referred to paediatricians. Both disorders show similarities in trigger and comorbid factors, their burden on family and individual life, and a paroxysmal trend with risks of chronicization over time. However, very few studies have compared directly headache and RAP. The main aim of this study was to compare the psychological profile of headache and RAP patients vs. healthy controls. A total of 210 children and adolescents [99 boys, 111 girls; age range 4-18 years; mean age (m.a.) = 11.04, SD 4.05] were assessed: 70 headache patients (m.a. 12.4 years; SD 2.9; F = 35, M = 35), 70 RAP patients (m.a. 9 years; SD 3.6; F = 30, M = 40) and 70 controls (m.a. 11.7 years; SD 4.6; F = 46, M = 24). The diagnoses had been made according to international systems of classification both for headache (ICHD-II criteria) and RAP (Rome II criteria). The psychological profile had been made according to the Child Behaviour Checklist 4-18 (CBCL). ANOVA one-way analysis was used to compare CBCL scales and subscales between groups. Headache and RAP showed a very similar trend vs. control for the main scales of the CBCL, with a statistically significant tendency to show problems in the Internalizing scale (anxiety, mood and somatic complaints) and no problems in the Externalizing (behavioural) scale. Only for the Attention Problems subscale migraineurs showed a significant difference compared with RAP. In conclusion, headache and RAP show a very similar psychological profile that should be considered not only for diagnostic and therapeutic purposes, but also from the aetiological aspect.
Topography‐driven flow versus buoyancy‐driven flow in the U.S. midcontinent: implications for the residence time of brines
Authors: THORNTON M. M. , WILSON A. M.
Published: January 2007

Topography‐driven flow is normally considered to be the dominant groundwater flow system in uplifted sedimentary basins. In the U.S. midcontinent region east of the Rocky Mountains, the presence of brines derived from dissolution of halite suggests that significant topography‐driven flushing has occurred to remove older brines that presumably formed concurrently with Permian evaporites in the basin. However, the presence of evaporites and brines in the modern basin suggests that buoyancy‐driven flow could limit topography‐driven flushing significantly. Here we used numerical models of variable‐density fluid flow, halite dissolution, solute transport, and heat transport to quantify flow patterns and brine migration. Results indicate the coexistence of large‐scale topography‐ and buoyancy‐driven flow. Buoyancy‐driven flow and low permeability evaporites act to isolate brines, and the residence time of the brines was found to be quite long, at least 50 Myr. The modern distribution of salinity appears to reflect near‐steady‐state conditions. Results suggest that flushing of original evaporatively‐concentrated brines occurred tens of millions of years ago, possibly concurrent with maximum uplift ca. 60 Ma. Simulations also suggest that buoyancy‐driven convection could drive chemical exchange with crystalline basement rocks, which could supply significant Ca2+, Sr2+, and metals to brines.
Genetic diversity and parasite defense in a fragmented urban metapopulation of earthworms
Authors: Field S. G. , Lange M. , Schulenburg H. , Velavan T. P. , Michiels N. K.
Published: January 2007

Habitat fragmentation can seriously affect the population biology and persistence of small isolated populations. We evaluated the interplay between the patch size of natural habitats, genetic diversity, immunocompetence and parasite load in an urban metapopulation of the earthwormLumbricus terrestris. Large‐scale genetic analysis of earthworm populations was accomplished using newly established mtDNA markers in combination with single‐strand conformation polymorphism haplotype screening. Our analysis yielded the following: (1) parasite load varied significantly among patches, but small versus large patches did not differ; a similar pattern was found for immunocompetence and genetic diversity; (2) in general, the urban metapopulation showed genetic structuring, which seems to be due to restricted gene flow among small and large patches; (3) the overall genetic variability of the patch has little or no effect on parasite load, as it was not significantly associated with parasite load; (4) small patches do not show molecular patterns associated with a general reduction in genetic diversity. These findings are in accordance with the view that among‐ and within‐patch components of genetic diversity approach equilibrium values at differing rates and suggest that the date of isolation (i.e. patch age) could be too recent for the expected pattern between genetic diversity, immunocompetence and parasite load to become evident. Our study provides initial insights into the population genetics of one of the most economically important soil organisms and, as such, will prove valuable as a primer for future research regarding the human impact on soil environments.
Behavioral responses of sea turtles to lightsticks used in longline fisheries
Authors: Wang J. H. , Boles L. C. , Higgins B. , Lohmann K. J.
Published: January 2007

Sea turtles are sometimes inadvertently captured by pelagic longline fisheries. As a consequence, some drown or suffer injuries, and longline bycatch has been identified as one factor contributing to the decline of marine turtle populations. Understanding what stimuli attract turtles to longlines will therefore be useful in efforts to reduce the number of turtles that become hooked or entangled. Lightsticks, which are often placed on longlines to attract tuna (Thunnus sp.) and swordfish Xiphus gladius, may also attract sea turtles. To investigate this possibility, we conducted laboratory experiments with captive‐reared juvenile loggerheads Caretta caretta and wild‐caught post‐hatchling loggerheads to study their responses to these lights. Both age classes oriented toward glowing lightsticks, suggesting that such lights may play a role in attracting turtles into the vicinity of longlines.
Ecological factors and human threats both drive wildfowl population declines
Authors: Long P. R. , Székely T. , Kershaw M. , O'Connell M.
Published: January 2007

Many wildfowl species are declining and 34 out of 159 extant species are globally threatened, some of which are the subject of specific conservation programmes. Here we investigate which factors predict declining population trends across 154 species of Anseriformes. First we show that there are proportionately fewer declining wildfowl populations in North America, Europe and Australasia than in south and central America, Africa and Asia. Second, we use phylogenetic comparative analyses to test whether population size, global range size and ecological, life‐history and sexually‐selected traits predict population trends. We also consider anthropogenic threats, and human impacts within the breeding and non‐breeding ranges of species. Using phylogenetically independent contrasts we show that small population size and small global ranges are the most important intrinsic factors that predispose wildfowl species to declining populations. Many wildfowl are hunted but, contrary to expectation, hunting did not influence population trends. Declining populations were associated with high International Union for the Conservation of Nature (IUCN) threat category, although the relationship is not very strong (r=0.134, n=129 contrasts) possibly because the IUCN criteria integrate population size, range size and an assessment of threat. Two extrinsic factors were significant predictors of population declines: the increase in area of agricultural land within a species' range (an indirect measure of wetland loss), and the total number of different threat processes such as habitat loss and pollution that threaten a species. Taken together, our results strongly suggest that both anthropogenic threats and intrinsic ecological factors are influencing population declines in wildfowl.
Pollen limitation meets resource allocation: towards a comprehensive methodology
Authors: Wesselingh Renate A.
Published: January 2007

The standard method of measuring pollen limitation is to add pollen to a number of flowers, preferably to a whole plant, and to compare fruit and seed set with that of naturally pollinated flowers on other plants. In 25 yr of research, this method has yielded valuable data, but it is difficult to use in large plants. This has caused a bias in the available data towards smaller, herbaceous plants with relatively few flowers. I argue that, in order to widen our knowledge of how pollen limitation affects plants, we should go beyond whole‐plant pollen addition and change our concept of how a flowering plant functions. The traditional method does not take into account the variation in and dynamics of resource allocation and pollen availability. The concept of integrated physiological units (IPUs) does, but, although it has been applied to pollination biology, it has not received the attention it deserves. I use this article to present its merits again, to propose a step‐by‐step methodology for studying pollen limitation, and to examine factors influencing possible plant strategies.
Azathioprine and breastfeeding—is it safe?
Authors: Sau A , Clarke S , Bass J , Kaiser A , Marinaki A , Nelson‐Piercy C
Published: January 2007

Traditionally, women receiving azathioprine have been discouraged from breastfeeding because of theoretical potential risks of neonatal bone marrow suppression, susceptibility to infection, and pancreatitis. The aims of this study were to measure the concentration of 6‐mercaptopurine (6‐MP) in breast milk of mothers receiving azathioprine and in the blood of their babies and to investigate any immunosuppressive effects on the babies. Women receiving azathioprine, who after appropriate counselling wished to breastfeed their babies, were approached for inclusion in the study. Breast milk samples were obtained from recruited women, and 6‐MP levels were measured in each breast milk sample. Haemoglobin level, white cell and platelet counts, and 6‐MP and 6‐thioguanine nucleotides (6‐TGN) levels were measured in the respective neonatal blood samples. Clinical signs of immunosuppression in the neonates were noted. Thirty‐one breast milk samples were collected from ten women. Low concentrations of 6‐MP (1.2 and 7.6 nanograms/ml, compared with therapeutic immunosuppressant level of 50 nanograms/ml in serum) were detected in two breast milk samples obtained from one woman. 6‐MP was not detected in any of the other 29 samples. 6‐MP and 6‐TGN were undetectable in the neonatal blood. There were no clinical or haematological signs of immunosuppression in any of the ten neonates. We conclude that breastfeeding should not be withheld in infants of mothers receiving azathioprine.
Caesarean delivery and risk of stillbirth in subsequent pregnancy: a retrospective cohort study in an English population
Authors: Gray R , Quigley MA , Hockley C , Kurinczuk JJ , Goldacre M , Brocklehurst P
Published: January 2007

Objective Two recent studies indicate an increased risk of stillbirth in the pregnancy that follows a pregnancy delivered by caesarean section. In this study, we report an analysis designed to test the hypothesis that delivery by caesarean section is a risk factor for explained or unexplained stillbirth in any subsequent pregnancy. We also report on the proportion of stillbirths in our study population, which may have been attributable to previous delivery by caesarean section.

Design Retrospective cohort study.

Population Linked statistical data set of 81 784 singleton deliveries registered in Oxfordshire and West Berkshire between 1968 and 1989.

Methods The crude and adjusted hazard ratios for stillbirth in deliveries following a previous delivery by caesarean section, compared with no previous caesarean, were estimated using Cox regression.

Main outcome measure Stillbirth.

Results The unadjusted hazard ratios for all, explained, and unexplained stillbirths were 1.54 (95% CI 1.04–2.29); 2.13 (1.22–3.72); and 1.19 (0.68–2.09), respectively. After adjustment for maternal age, parity, social class, previous adverse outcome of pregnancy, body mass indexand smoking the hazard ratios were 1.58 (0.95–2.63), 2.08 (1.00–4.31) and 1.24 (0.60–2.56).

Conclusions Pregnancies in women following a pregnancy delivered by caesarean section are at an increased risk of stillbirth. In our study, the risk appears to be mainly concentrated in the subgroup of explained stillbirths. However, there are sufficient inconsistencies in the developing literature about stillbirth risk that further research is needed.
Modulation of inflammation in brain: a matter of fat
Authors: Farooqui Akhlaq A. , Horrocks Lloyd A. , Farooqui Tahira
Published: January 2007

Neuroinflammation is a host defense mechanism associated with neutralization of an insult and restoration of normal structure and function of brain. Neuroinflammation is a hallmark of all major CNS diseases. The main mediators of neuroinflammation are microglial cells. These cells are activated during a CNS injury. Microglial cells initiate a rapid response that involves cell migration, proliferation, release of cytokines/chemokines and trophic and/or toxic effects. Cytokines/chemokines stimulate phospholipases A2 and cyclooxygenases. This results in breakdown of membrane glycerophospholipids with the release of arachidonic acid (AA) and docosahexaenoic acid (DHA). Oxidation of AA produces pro‐inflammatory prostaglandins, leukotrienes, and thromboxanes. One of the lyso‐glycerophospholipids, the other products of reactions catalyzed by phospholipase A2, is used for the synthesis of pro‐inflammatory platelet‐activating factor. These pro‐inflammatory mediators intensify neuroinflammation. Lipoxin, an oxidized product of AA through 5‐lipoxygenase, is involved in the resolution of inflammation and is anti‐inflammatory. Docosahexaenoic acid is metabolized to resolvins and neuroprotectins. These lipid mediators inhibit the generation of prostaglandins, leukotrienes, and thromboxanes. Levels of prostaglandins, leukotrienes, and thromboxanes are markedly increased in acute neural trauma and neurodegenerative diseases. Docosahexaenoic acid and its lipid mediators prevent neuroinflammation by inhibiting transcription factor NFκB, preventing cytokine secretion, blocking the synthesis of prostaglandins, leukotrienes, and thromboxanes, and modulating leukocyte trafficking. Depending on its timing and magnitude in brain tissue, inflammation serves multiple purposes. It is involved in the protection of uninjured neurons and removal of degenerating neuronal debris and also in assisting repair and recovery processes. The dietary ratio of AA to DHA may affect neurodegeneration associated with acute neural trauma and neurodegenerative diseases. The dietary intake of docosahexaenoic acid offers the possibility of counter‐balancing the harmful effects of high levels of AA‐derived pro‐inflammatory lipid mediators.
The effect of environmental variables on soil characteristics at different scales in the transition zone of the Loess Plateau in China
Authors: Liu S. L. , Guo X. D. , Fu B. J. , Lian G. , Wang J.
Published: January 2007

As a result of human disturbance and topographic variability, land use mosaics are characteristic of the transition zone of the Loess Plateau in Shaanxi Province, China. Soils are particularly sensitive to change when land degradation processes are dominant. An understanding of the influences of environmental variables is required to inform land management and agricultural production. In this study the relationships between land type, topography and soil properties were analysed for Hengshan County at two different scales using detrended canonical correspondence analysis. The results show that variations in soil properties are strongly influenced by topography, land use and vegetation. Slope, elevation and aspect are also of importance at the county and small catchment scales of analysis. Though land use type proved to be of lesser importance than topographic factors, ANOVA analysis showed that there were significant differences in soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), available nitrogen, available potassium and clay %. Areas under vegetables had significantly higher SOM and TN content at the catchment scale. The results will enhance our ability to predict spatial and temporal changes in soils. In addition, it is shown that soil fertility could be improved by land reform and management in the hilly‐gully area.
Qualitative Data Analysis for Health Services Research: Developing Taxonomy, Themes, and Theory
Authors: Bradley Elizabeth H. , Curry Leslie A. , Devers Kelly J.
Published: January 2007

Objective. To provide practical strategies for conducting and evaluating analyses of qualitative data applicable for health services researchers.

Data Sources and Design. We draw on extant qualitative methodological literature to describe practical approaches to qualitative data analysis. Approaches to data analysis vary by discipline and analytic tradition; however, we focus on qualitative data analysis that has as a goal the generation of taxonomy, themes, and theory germane to health services research.

Principle Findings. We describe an approach to qualitative data analysis that applies the principles of inductive reasoning while also employing predetermined code types to guide data analysis and interpretation. These code types (conceptual, relationship, perspective, participant characteristics, and setting codes) define a structure that is appropriate for generation of taxonomy, themes, and theory. Conceptual codes and subcodes facilitate the development of taxonomies. Relationship and perspective codes facilitate the development of themes and theory. Intersectional analyses with data coded for participant characteristics and setting codes can facilitate comparative analyses.

Conclusions. Qualitative inquiry can improve the description and explanation of complex, real‐world phenomena pertinent to health services research. Greater understanding of the processes of qualitative data analysis can be helpful for health services researchers as they use these methods themselves or collaborate with qualitative researchers from a wide range of disciplines.
Hospice Care: What Services Do Patients and Their Families Receive?
Authors: Carlson Melissa D. A. , Morrison R. Sean , Holford Theodore R. , Bradley Elizabeth H.
Published: January 2007

Objective. To determine the degree to which patients and families enrolled with hospice received services across key categories of palliative care, the extent of hospice‐level variability in services delivered, and changes over time in services delivered.

Data Source. Nationally representative sample of 9,409 discharged patients from 2,066 hospices in the National Home and Hospice Care Survey.

Study Design. Observational, cross‐sectional study conducted from 1992 to 2000. The primary outcome is the receipt of services across five key categories of palliative care: nursing care, physician care, medication management, psychosocial care, and caregiver support.

Data Collection. Data were obtained via interview with the hospice staff member most familiar with the patient's care, in conjunction with medical record review.

Principle Findings. In 2000, 22 percent of patients enrolled with hospice received services across five key categories of palliative care. There was marked variation across hospices in service delivery. One‐third of hospices provided patients and families services in one or two of the five key categories of palliative care, whereas 14 percent of hospices provided services across five key categories of palliative care. In multivariable analysis, the odds of receiving any additional hospice service was significantly greater in later compared with earlier years (odds ratio=1.10, 95 percent confidence interval 1.01–1.20). Nevertheless, the percentages of patients in 2000 receiving medication management (59 percent), respite care (7 percent), and physician services (30 percent) remained low.

Conclusions. Hospice care for patients and families varies substantially across hospices. Whereas some hospices provide services across the key categories of palliative care, other hospices do not provide this breadth of services. Greater understanding of the causes of variation in service delivery as well as its impact on patient and family outcomes and satisfaction with end‐of‐life care is a critical subject for future research. Changes in Medicare's reimbursement policies may help hospices increase the range of services provided to patients and families.
Notes from the Field: Jumpstarting the IRB Approval Process in Multicenter Studies
Authors: Blustein Jan , Regenstein Marsha , Siegel Bruce , Billings John
Published: January 2007

Objective. To identify strategies that facilitate readiness for local Institutional Review Board (IRB) review, in multicenter studies.

Study Setting. Eleven acute care hospitals, as they applied to participate in a foundation‐sponsored quality improvement collaborative.

Study Design. Case series.

Data Collection/Extraction. Participant observation, supplemented with review of written and oral communications.

Principal Findings. Applicant hospitals responded positively to efforts to engage them in early planning for the IRB review process. Strategies that were particularly effective were the provisions of application templates, a modular approach to study description, and reliance on conference calls to collectively engage prospective investigators, local IRB members, and the evaluation/national program office teams. Together, these strategies allowed early identification of problems, clarification of intent, and relatively timely completion of the local IRB review process, once hospitals were selected to participate in the learning collaborative.

Conclusions. Engaging potential collaborators in planning for IRB review may help expedite and facilitate review, without compromising the fairness of the grant‐making process or the integrity of human subjects protection.
Time Allocation in Primary Care Office Visits
Authors: Tai‐Seale Ming , McGuire Thomas G. , Zhang Weimin
Published: January 2007

Objectives. To use an innovative videotape analysis method to examine how clinic time was spent during elderly patients' visits to primary care physicians. Secondary objectives were to identify the factors that influence time allocations.

Data Sources. A convenience sample of 392 videotapes of routine office visits conducted between 1998 and 2000 from multiple primary care practices in the United States, supplemented by patient and physician surveys.

Research Design. Videotaped visits were examined for visit length and time devoted to specific topics—a novel approach to study time allocation. A survival analysis model analyzed the effects of patient, physician, and physician practice setting on how clinic time was spent.

Principal Findings. Very limited amount of time was dedicated to specific topics in office visits. The median visit length was 15.7 minutes covering a median of six topics. About 5 minutes were spent on the longest topic whereas the remaining topics each received 1.1 minutes. While time spent by patient and physician on a topic responded to many factors, length of the visit overall varied little even when contents of visits varied widely. Macro factors associated with each site had more influence on visit and topic length than the nature of the problem patients presented.

Conclusions. Many topics compete for visit time, resulting in small amount of time being spent on each topic. A highly regimented schedule might interfere with having sufficient time for patients with complex or multiple problems. Efforts to improve the quality of care need to recognize the time pressure on both patients and physicians, the effects of financial incentives, and the time costs of improving patient–physician interactions.
Factors Associated with the Income Distribution of Full‐Time Physicians: A Quantile Regression Approach
Authors: Shih Ya‐Chen Tina , Konrad Thomas R.
Published: January 2007

Objective. Physician income is generally high, but quite variable; hence, physicians have divergent perspectives regarding health policy initiatives and market reforms that could affect their incomes. We investigated factors underlying the distribution of income within the physician population.

Data Sources. Full‐time physicians (N=10,777) from the restricted version of the 1996–1997 Community Tracking Study Physician Survey (CTS‐PS), 1996 Area Resource File, and 1996 health maintenance organization penetration data.

Study Design. We conducted separate analyses for primary care physicians (PCPs) and specialists. We employed least square and quantile regression models to examine factors associated with physician incomes at the mean and at various points of the income distribution, respectively. We accounted for the complex survey design for the CTS‐PS data using appropriate weighted procedures and explored endogeneity using an instrumental variables method.

Principal Findings. We detected widespread and subtle effects of many variables on physician incomes at different points (10th, 25th, 75th, and 90th percentiles) in the distribution that were undetected when employing regression estimations focusing on only the means or medians. Our findings show that the effects of managed care penetration are demonstrable at the mean of specialist incomes, but are more pronounced at higher levels. Conversely, a gender gap in earnings occurs at all levels of income of both PCPs and specialists, but is more pronounced at lower income levels.

Conclusions. The quantile regression technique offers an analytical tool to evaluate policy effects beyond the means. A longitudinal application of this approach may enable health policy makers to identify winners and losers among segments of the physician workforce and assess how market dynamics and health policy initiatives affect the overall physician income distribution over various time intervals.
The Role of the Intracarotid Amobarbital Procedure in Predicting Verbal Memory Decline after Temporal Lobe Resection
Authors: Baxendale Sallie , Thompson Pamela , Harkness William , Duncan John
Published: January 2007

Summary:  Purpose: The aim of this study was to compare the utility of baseline neuropsychological measures and scores from the intracarotid amobarbital procedure (IAP) in the prediction of postoperative memory decline in temporal lobe epilepsy surgery patients.

Methods: Logistic regression analyses were used to determine the relation between demographic variables, baseline neuropsychological scores, and scores from the IAP (using mixed verbal and nonverbal stimuli) and postoperative deterioration in verbal learning and verbal recall in 91 patients (48 right, RTL; 43 left, LTL) who had undergone a standard anterior temporal lobe resection for the relief of medically intractable epilepsy and who had been followed up 1 year postoperatively.

Results: In the RTL group, the IAP scores were not significant predictors of a postoperative decline in verbal learning or recall. In the LTL group, postoperative decline in verbal learning was associated with good preoperative baseline scores, an older age at the time of surgery, and an unexpected asymmetry on the IAP. Baseline neuropsychological scores and scores from the IAP were associated with a significant postoperative decline in verbal recall in the LTL group.

 Conclusions: Scores from the IAP using mixed stimuli were not helpful in the prediction of postoperative verbal memory decline in RTL patients. The significance of IAP scores in predicting verbal memory deficits in LTL patients may be task specific.