bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modulation of the Homocysteine-Betaine Relationship by Methylenetetrahydrofolate Reductase 677 C-&gt;T Genotypes and B-Vitamin Status in a Large-Scale Epidemiological Study
Authors: Holm Pål I. , Hustad Steinar , Ueland Per Magne , Vollset Stein Emil , Grotmol Tom , Schneede Jørn 
Published: February 2007

AbstractContext: Betaine is formed from the essential nutrient choline or is supplied from the diet. It serves as a substrate in the betaine-homocysteine methyltransferase reaction and thereby provides methyl groups for the homocysteine-methionine cycle, which is regulated by enzymes dependent on folate, vitamin B12, riboflavin (vitamin B2), or vitamin B6.Objective: We investigated how betaine affected total homocysteine (tHcy) concentration within the frame of variable B-vitamin status and according to the methylenetetrahydrofolate reductase (MTHFR) 677C-&gt;T genotype.Design/Setting/Patients: This is a population-based study with a cross-sectional design. It includes 10,601 healthy men and women aged 50–64 yr.Outcome Measures: Plasma samples were analyzed for tHcy, betaine, choline, dimethylglycine, riboflavin, and vitamin B6, whereas folate and vitamin B12 were analyzed in serum.Results: Betaine was a strong determinant of plasma tHcy in subjects with low serum folate and the MTHFR TT genotype. The association was further strengthened at low levels in the circulation of the other B-vitamins (B2, B6, and B12). Thus, in subjects with the combination of serum folate in the lowest quartile, low vitamin B2, B6, and B12 status, and the MTHFR TT genotype, the difference in tHcy (mean, 95% confidence interval) across extreme plasma betaine quartiles was 8.8 (1.3–16.2) μmol/liter.Conclusion: Betaine may thus be an important one-carbon source, particularly in MTHFR 677 TT subjects with inadequate B-vitamin status.
Impaired Sexual and Reproductive Outcomes in Women with Classical Forms of Congenital Adrenal Hyperplasia
Authors: Gastaud F. , Bouvattier C. , Duranteau L. , Brauner R. , Thibaud E. , Kutten F. , Bougnères P. 
Published: February 2007

Abstract
Objectives: The objectives of the study were 2-fold: 1) a detailed description of sexual and reproductive outcomes in adult women with congenital adrenal hyperplasia (CAH) of different phenotypic severity at birth; and 2) comparisons of these outcomes among CAH subtypes and between CAH women and non-CAH control women.
Design: This was a cross-sectional study using a face-to-face interview, a written questionnaire, the Female Sexual Function Index, and a gynecological examination.
Patients: Patients included 35 women with CAH, representing Prader stages I–V at birth, aged 18–43 yr, who had been treated from birth to adolescence in the same pediatric endocrine clinics. Sixty-nine non-CAH healthy control women were selected from hospital-staff families.
Results: None of the CAH women expressed doubts about their gender assignment. Twenty percent (seven of 35) had homosexual inclinations; 23% (eight of 35) were married; three reported a complete lack of sexual activity; and 37% (13 of 35) said they never had heterosexual intercourse with vaginal penetration. Sexual functioning as assessed by the Female Sexual Function Index was much lower in CAH women than controls and lowest in CAH women with high Prader stages. Eighty-one percent (18 of 22) experienced pain during vaginal penetration. Only eight women became pregnant, and 17% (six of 35) had children.
Conclusions: Despite expert medical and surgical care by physicians dedicated to this rare disease, women with CAH still suffer major limitations in their sexual function and reproductive life.
Androgens in Women with Anorexia Nervosa and Normal-Weight Women with Hypothalamic Amenorrhea
Authors: Miller K. K. , Lawson E. A. , Mathur V. , Wexler T. L. , Meenaghan E. , Misra M. , Herzog D. B. , Klibanski A. 
Published: February 2007

Abstract
Context: Anorexia nervosa and normal-weight hypothalamic amenorrhea are characterized by hypogonadism and hypercortisolemia. However, it is not known whether these endocrine abnormalities result in reductions in adrenal and/ or ovarian androgens or androgen precursors in such women, nor is it known whether relative androgen deficiency contributes to abnormalities in bone density and body composition in this population.
Objective: Our objective was to determine whether endogenous androgen and dehydroepiandrosterone sulfate (DHEAS) levels: 1) are reduced in women with anorexia nervosa and normal-weight hypothalamic amenorrhea, 2) are reduced further by oral contraceptives in women with anorexia nervosa, and 3) are predictors of weight, body composition, or bone density in such women.
Design and Setting: We conducted a cross-sectional study at a general clinical research center.
Study Participants: A total of 217 women were studied: 137 women with anorexia nervosa not receiving oral contraceptives, 32 women with anorexia nervosa receiving oral contraceptives, 21 normal-weight women with hypothalamic amenorrhea, and 27 healthy eumenorrheic controls.
Main Outcome Measures: Testosterone, free testosterone, DHEAS, bone density, fat-free mass, and fat mass were assessed.
Results: Endogenous total and free testosterone, but not DHEAS, were lower in women with anorexia nervosa than in controls. More marked reductions in both free testosterone and DHEAS were observed in women with anorexia nervosa receiving oral contraceptives. In contrast, normal-weight women with hypothalamic amenorrhea had normal androgen and DHEAS levels. Lower free testosterone, total testosterone, and DHEAS levels predicted lower bone density at most skeletal sites measured, and free testosterone was positively associated with fat-free mass.
Conclusions: Androgen levels are low, appear to be even further reduced by oral contraceptive use, and are predictors of bone density and fat-free mass in women with anorexia nervosa. Interventional studies are needed to confirm these findings and determine whether oral contraceptive use, mediated by reductions in endogenous androgen levels, is deleterious to skeletal health in such women.
Cranial Irradiation and Growth Hormone Neurosecretory Dysfunction: A Critical Appraisal
Authors: Darzy Ken H. , Pezzoli Suzan S. , Thorner Michael O. , Shalet Stephen M. 
Published: February 2007

AbstractContext: It has been suggested that radiation-induced GH neurosecretory dysfunction exists in children; however, the pathophysiology is poorly understood, and it is unknown if such a phenomenon exists in adult life.Study Subjects: Twenty-four-hour spontaneous GH secretion was studied by 20-min sampling both in the fed state (n = 16; six women) and the last 24 h of 33-h fast (n = 10; three women) in adult cancer survivors of normal GH status defined by two GH provocative tests, 13.1 ± 1.6 (range, 3–28) yr after cranial irradiation (18–40 Gy) for nonpituitary brain tumors (n = 12) or leukemia (n = 4) in comparison with 30 (nine women) age- and body mass index-matched normal controls (fasting, 11 men and three women).Results: Using previously published diagnostic thresholds, all patients had stimulated peak GH responses in the normal range to both the insulin tolerance test and the combined GHRH plus arginine stimulation test, as well as normal individual mean profile GH levels during the fed and fasting states. However, gender-specific comparisons revealed marked reduction (by 40%) in the overall peak GH responses to both provocative tests but similar GH secretory profiles; no differences were seen in the pulsatile attributes of GH secretion (cluster analysis) or the profile absolute and mean GH levels in the fed state or when the hypothalamic-pituitary axis was stimulated by fasting.Conclusions: Radiation-induced GH neurosecretory dysfunction either does not exist or is a very rare phenomenon in irradiated adult cancer survivors. The normality of physiological GH secretion in the context of reduced maximum somatotroph reserve suggests compensatory overdrive of the partially damaged somatotroph axis and constitutes a relative argument against somatotroph dysfunction being explained purely by hypothalamic damage with secondary atrophy due to GHRH deficiency. It is therefore possible that radiation in doses less than 40 Gy causes dual damage to both the pituitary and the hypothalamus.
Influence of an Interactive Computer-Based Inhaler Technique Tutorial on Patient Knowledge and Inhaler Technique
Authors: Navarre Matt , Patel Hiral , Johnson Cary E , Durance Ann , McMorris Marc , Bria William , Erickson Steven R 
Published: February 2007

Background: Patient knowledge of correct inhaler technique is essential in the treatment of pulmonary disease. Computer delivery of educational content may augment existing teaching efforts. Objective: To determine whether a computer-based tutorial on inhaler technique could improve patients' knowledge and ability to correctly demonstrate inhaler technique. Methods: A total of 34 adults with pulmonary disease and experience using inhalers were randomized into the control or intervention groups. The intervention group viewed the tutorial, after which they demonstrated their inhaler technique and completed an Inhaler Technique Knowledge Test. Control group patients, who did not view the tutorial, were also evaluated on their demonstrated inhaler technique and technique knowledge. Additional information obtained included demographics, illness and treatment history, and patients' use of computers. Lastly, all patients who viewed the tutorial completed a brief questionnaire eliciting tutorial feedback. Control group patients were invited to view the tutorial after other data collection was complete. The 2 principal outcomes were the observed inhaler technique score and the inhaler technique knowledge test score. Comparisons between groups were conducted using Student's t-test and χ2 test, with a p value less than 0.05 considered statistically significant. Results: Eighteen subjects were enrolled in the computer group; 16 were in the control group. The intervention group demonstrated significantly better inhaler technique, with a mean Observed Inhaler Technique Score of 88.3 ± 12.3 compared with 67.4 ± 19.2 for the control group (p = 0.001). The intervention group also scored significantly higher on the Inhaler Technique Knowledge Test, with a score of 80.9 ± 17.0 versus 67.4 ± 11.8 for the control group (p = 0.01). Overall, the program appeared acceptable to patients. Conclusions: Patients in the tutorial group demonstrated better inhaler technique and scored higher on the Inhaler Technique Knowledge Test compared with those in a control group. This tutorial may be a useful educational tool to enhance patient education regarding inhaler technique.
Pyridostigmine in the Treatment of Orthostatic Intolerance
Authors: Gales Barry J , Gales Mark A 
Published: February 2007

Objective: To review the efficacy of pyridostigmine bromide for the treatment of orthostatic intolerance. Data Sources: MEDLINE and International Pharmaceutical Abstracts were searched (1966–December 2006) using the terms pyridostigmine, acetylcholinesterase inhibitor, orthostatic intolerance, orthostatic hypotension, neurogenic orthostatic hypotension, postural tachycardia syndrome, tachycardia, and orthostatic tachycardia. Study Selection and Data Extraction: Pertinent English-language human clinical trials, case reports, and background material were evaluated for safety and efficacy data. The references of reviewed articles were reviewed and used to identify additional sources. Data Synthesis: Pyridostigmine bromide has been associated with improved baroreceptor sensitivity and presents a novel approach to treatment of orthostatic intolerance. Four single-dose trials and a follow-up survey encompassing a total of 106 patients were identified. One open-label and one placebo-controlled single-dose trial in patients with neurogenic orthostatic hypotension (NOH) found statistically significant improvement in standing diastolic blood pressures (DBP). Absolute improvements in standing DBP were 3.7 and 6.4 mm Hg in the open-label and controlled trials, respectively. Long-term data consist of a single survey of patients receiving open-label pyridostigmine bromide. Twenty-nine percent of patients who initiated maintenance pyridostigmine bromide discontinued therapy. Concomitant NOH medications were taken by 75% of patients, and 85% of patients reported receiving benefit from pyridostigmine bromide. When evaluated for postural tachycardia syndrome, pyridostigmine bromide significantly reduced standing heart rate (10%). Pyridostigmine bromide significantly reduced symptom scores when compared with baseline but not placebo. The majority of patients included in these trials did not have supine hypertension. Conclusions: Single doses of pyridostigmine bromide produced modest but statistically significant improvements in hemodynamic measurements. At this time, long-term data are insufficient to support recommending the routine use of pyridostigmine bromide for treatment of orthostatic intolerance.
The impact of immigration on the internal migration of natives and immigrants
Authors: Kritz Mary M. , Gurak Douglas T. 
Published: February 2007

Abstract
In this paper we examine the internal migratory response, by native-born non-Hispanic white men and foreign-born men in the United States, to recent immigration. Our analysis does not support the claim that natives have made a migratory response to recent immigration. Native-born men and foreign-born men were less likely to leave states that received large numbers of immigrants in the 1980s than they were to leave other states, and native-born men had less propensity toward out-migration than did foreign-born men. Out-migration was most likely to be deterred if recent immigrants originated in Europe or Asia. Although native-born non-Hispanic white men showed a tendency toward out-migration if recent immigrants originated in Latin America or the Caribbean, this result was insignificant after we controlled for state economic and regional context.
On the auspices of female migration from Mexico to the United States
Authors: Cerrutti Marcela , Massey Douglas S. 
Published: February 2007

AbstractIn this paper we examine the circumstances and determinants of female migration between Mexico and the United States. Using data from the Mexican Migration Project, we considered the relative timing of males’ and females’ moves northward. We then estimated logit and probit models to study the determinants of male and female out-migration; among women we also estimated a multinomial logit model to uncover differences in the process of migration for work versus not for work. We found that women almost always followed other family members, either the husband or a parent; only a tiny minority initiated migration independently. Although males also are quite likely to be introduced to migration by a parent, nearly half of all male migrants left for the United States before or without a wife or a parent. Estimates of the determinants of migration suggested that males move for employment, whereas wives generally are motivated by family reasons. Daughters, however, display a greater propensity to move for work, and the determinants of their work-related moves closely re semble those of sons and fathers.
The living arrangements of new unmarried mothers
Authors: Sigle-Rushton Wendy , McLanahan Sara 
Published: February 2007

Abstract
We use data from the Fragile Families and Child Wellbeing Study to describe the living arrangements of new, unwed mothers and to examine the selection process that underlies choices of living arrangements. Our analysis goes beyond previous studies by examining a wide diversity of living arrangements for a homogenous sample of recent unwed mothers and by using information on both parents’ demographic and human capital characteristics and the quality of their relationships. We find that about half the new unwed mothers are cohabiting at the time their children are born, and only 17% are living alone. We also find that mothers’ choices of living arrangements are significantly related to parents’ human capital, the quality of their relationship, and the cost of housing.
Assessing immigrant policy options: Labor market conditions and postreform declines in immigrants’ receipt of welfare
Authors: Lofstrom Magnus , Bean Frank D. 
Published: February 2007

Abstract
Researchers infrequently have focused on assessing the degree to which the changes in welfare policy legislated during the 1990s have affected immigrants’ receipt of welfare. Using data from the March Current Population Survey, we analyze the contribution of local labor market conditions to the explanation of relative declines in immigrants’ receipt of welfare from 1994 to 2000. The results of a series of models that included labor market-area and state fixed effects indicate that employment and unemployment rates across metropolitan statistical areas and states account for at least one-third of the observed relative decrease among immigrants. The policy implications of the findings are discussed.
Women’s autonomy and child survival: A comparison of muslims and non-muslims in four Asian countries
Authors: Ghuman Sharon J. 
Published: February 2007

Abstract
In this article, I evaluate the hypothesis that higher infant and child mortality among Muslim populations is related to the lower autonomy of Muslim women using data from 15 pairs of Muslim and non-Muslim communities in India, Malaysia, the Philippines, and Thailand. Women’s autonomy in various spheres is not consistently lower in Muslim than in non-Muslim settings. Both across and within communities, the association between women’s autonomy and mortality is weak, and measures of autonomy or socioeconomic status are generally of limited import for understanding the Muslim disadvantage in children’s survival.
The racial crossover in family complexity in the United States
Authors: Goldscheider Frances K. , Bures Regina M. 
Published: February 2007

AbstractThis article examines the evolution of the black extended family by documenting a black-white crossover in the proportions of unmarried adults living in complex households after the middle of the twentieth century. We demonstrate significant racial differences in the trends in complex household residence over the life course, characterized by far greater declines in complex living among whites, particularly at younger ages. In this context, the higher level of family extension that recent research has found typifies black families is both a relatively new phenomenon and one that is not just limited to single-parent families; it characterizes all ages, those with and without children, and men as well as women.
Sharing the wealth: The effect of siblings on adults’ wealth ownership
Authors: Keister Lisa A. 
Published: February 2007

Abstract
Inequality in wealth has been well-documented, but its causes remain uncertain. Family processes in childhood are likely to shape adults’ wealth accumulation, but these factors have attracted little attention. I argue that family size matters: children from larger families accumulate less wealth than do those from smaller families. Siblings dilute parents’ finite financial resources and nonmaterial resources, such as time. This diminishment of resources reduces educational attainment, inter vivos transfers, and inheritance. Reduced educational attainment and transfers alter financial behavior; saving; and, ultimately, adults’ wealth. I demonstrate that sibship size is associated with lower overall wealth in adulthood and that parents’ resources and education, respondent’s education, financial transfers, and financial behavior all mitigate the effect of siblings. Sibship size also reduces the likelihood of receiving a trust account or an inheritance and decreases home- and stock ownership. The findings provide important insights into early family processes that shape wealth accumulation and inequality.
The academic trajectories of immigrant youths: Analysis within and across cohorts
Authors: Glick Jennifer E. , White Michael J. 
Published: February 2007

Abstract
Two nationally representative cohorts—from the National Educational Longitudinal Study (NELS) and High School and Beyond (HSB)—were used to examine the effects of generation and duration of residence on students’ performance on standardized tests over a two-year period. In multivariate models, generational status predicts variation in students’ performance on baseline (sophomore) tests, with effects stronger for the later age cohort (NELS) than for the earlier age cohort (HSB). With regard to the trajectory of achievement, generational status has a greatly reduced role for both cohorts. The best predictors of the trajectory of achievement are not those that are based on nativity per se, but those that reflect the social environment experienced in the United States (i.e., ethnicity and family’s socioeconomic status).
Is low fertility a twenty-first-century demographic crisis?
Authors: Morgan S. Philip 
Published: February 2007

AbstractNearly half of the world’s population in 2000 lived in countries with fertility rates at or below replacement level, and nearly all countries will reach low fertility levels in the next two decades. Concerns about low fertility, fertility that is well below replacement, are widespread. But there are both persistent rationales for having children and institutional adjustments that can make the widespread intentions for two children attainable, even in increasingly individualistic and egalitarian societies.
Mare Liberum vs. Mare Clausum : Grotius, Freitas, and Selden's Debate on Dominion over the Seas
Authors: Vieira Monica Brito 
Published: February 2007

Sixteen years after the publication of Grotius’s Mare Liberum (1609), Serafim de Freitas, a Portuguese friar, published a reply to Grotius’s attack upon the foundations of the Iberian overseas empire. Freitas’s vindication of the Portuguese dominion over the high seas has, however, been consigned to obscurity, as the Anglophone literature concentrated on John Selden’s Mare Clausum (1636). This neglect is unjustified. Not only is Freitas’s treatise an earlier and more systematic response to Grotius, but it also anticipates many of the arguments later deployed by Selden. The purpose of this article is thus to rescue Freitas’s arguments from oblivion.
The Neural Code of Auditory Phantom Perception
Authors: Weisz Nathan , Müller Simona , Schlee Winfried , Dohrmann Katalin , Hartmann Thomas , Elbert Thomas 
Published: February 2007

Tinnitus is defined by an auditory perception in the absence of an external source of sound. This condition provides the distinctive possibility of extracting neural coding of perceptual representation. Previously, we had established that tinnitus is characterized by enhanced magnetic slow-wave activity (∼4 Hz) in perisylvian or putatively auditory regions. Because of works linking high-frequency oscillations to conscious sensory perception and positive symptoms in a variety of disorders, we examined gamma band activity during brief periods of marked enhancement of slow-wave activity. These periods were extracted from 5 min of resting spontaneous magnetoencephalography activity in 26 tinnitus and 21 control subjects. Results revealed the following, particularly within a frequency range of 50–60 Hz: (1) Both groups showed significant increases in gamma band activity after onset of slow waves. (2) Gamma is more prominent in tinnitus subjects than in controls. (3) Activity at ∼55 Hz determines the laterality of the tinnitus perception.Based on present and previous results, we have concluded that cochlear damage, or similar types of deafferentation from peripheral input, triggers reorganization in the central auditory system. This produces permanent alterations in the ongoing oscillatory dynamics at the higher layers of the auditory hierarchical stream. The change results in enhanced slow-wave activity reflecting altered corticothalamic and corticolimbic interplay. Such enhancement facilitates and sustains gamma activity as a neural code of phantom perception, in this case auditory.