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Rationale: Asthma is a chronic inflammatory airway disease that affects more than 300 million individuals worldwide. Asthma is caused by interaction of genetic and environmental factors. Bronchial hyperresponsiveness (BHR) is a hallmark of asthma and results from increased sensitivity of the airways to physical or chemical stimulants. BHR and asthma are linked to chromosome 5q31-q33.Objectives: To identify a gene for BHR on chromosome 5q31-q33.Methods: In 200 Dutch families with asthma, linkage analysis and fine mapping were performed, and the Protocadherin 1 gene (PCDH1) was identified. PCDH1 was resequenced in 96 subjects from ethnically diverse populations to identify novel sequence variants. Subsequent replication studies were undertaken in seven populations from The Netherlands, the United Kingdom, and the United States, including two general population samples, two family samples, and three case-control samples. PCDH1 mRNA and protein expression was investigated using polymerase chain reaction, Western blotting, and immunohistochemistry.Measurements and Main Results: In seven out of eight populations (n = 6,168) from The Netherlands, United Kingdom, and United States, PCHD1 gene variants were significantly associated with BHR (P values, 0.005-0.05) This association was present in both families with asthma and general populations. PCDH1 mRNA and protein were expressed in airway epithelial cells and in macrophages.Conclusions: PCDH1 is a novel gene for BHR in adults and children. The identification of PCDH1 as a BHR susceptibility gene may suggest that a structural defect in the integrity of the airway epithelium, the first line of defense against inhaled substances, contributes to the development of BHR. [ABSTRACT FROM AUTHOR]

BACKGROUND: It has long been recognized that many children with asthma outgrow the disease after the onset of puberty, but little is known about genetic factors influencing this outcome. OBJECTIVES: The aim of the present study was to determine whether the polymorphisms at codons 16 and 27 of the beta2-adrenoceptor are significant predictors of the persistence of asthma during adolescence. DESIGN AND PARTICIPANTS: We used data from the prospective Tucson Children's Respiratory Study. Children were genotyped for the polymorphisms at codons 16 and 27. The presence of wheezing/asthma was assessed by questionnaire from age 6 years up to the reported onset of puberty (prepubertal period) and after the onset of puberty up to age 16 years (adolescence). RESULTS: Among children who wheezed in the prepubertal period (n = 168), subjects homozygous for Gly at codon 16 were at significantly increased risk for persistent wheezing after puberty, as compared with carriers of the other genotypes (relative risk [RR], 1.43; 95% confidence interval [CI], 1.06 to 1.92; p = 0.019). This relation was present among boys (RR, 2.17; 95% CI, 1.41 to 3.36) but not girls (RR, 0.85; 95% CI, 0.55 to 1.30), and increased linearly according to the frequency of wheezing episodes after the onset of puberty. These findings persisted after adjusting for ethnicity and other potential confounders and after selecting only white children. The polymorphism at codon 27 showed no relation with risk for persistent wheezing. CONCLUSIONS: This study provides evidence for a strong gender-specific effect of the Gly16 polymorphism on the persistence of asthma after the onset of puberty. [ABSTRACT FROM AUTHOR]

Complex relationships between race and socioeconomic status have a poorly understood influence on psychologic outcomes in pediatric oncology. The Family Symptom Inventory was used to assess symptoms of depression and anxiety in pediatric patients with cancer and their caregivers. Separate hierarchical linear regression models examined the relationship between demographic variables, cancer characteristics, socioeconomic status, and access to care and patient or caregiver depression/anxiety. Participants included 196 pediatric patients with cancer (mean age, 11.21 y; 49% African American) and their caregivers. On average, caregivers reported low levels of depression/anxiety. Symptoms of depression and anxiety in patients were correlated with poorer mental health in caregivers (r=0.62; P<0.01). Self-reported financial difficulty (β=0.49; P<0.001) and brain cancer diagnosis for their child (β=0.42; P=0.008) were significantly associated with depression and anxiety in caregivers. Analysis did not reveal significant associations between race, household income, or access to care and patient or caregiver depression/anxiety. Perception of financial hardship can adversely impact mental health in caregivers of children with cancer. Psychosocial assessment and interventions may be especially important for caregivers of patients with brain tumors and caregivers who report feeling financial difficulty.

We examined common variation in asthma risk by conducting a meta-analysis of worldwide asthma genome-wide association studies (23,948 asthma cases, 118,538 controls) of individuals from ethnically diverse populations. We identified five new asthma loci, found two new associations at two known asthma loci, established asthma associations at two loci previously implicated in the comorbidity of asthma plus hay fever, and confirmed nine known loci. Investigation of pleiotropy showed large overlaps in genetic variants with autoimmune and inflammatory diseases. The enrichment in enhancer marks at asthma risk loci, especially in immune cells, suggested a major role of these loci in the regulation of immunologically related mechanisms.

Introduction: Caring for children with oncological and hematological disorders may lead to caregiver emotional distress and caregiver burden; however, little work has examined the relationship between children's symptoms and caregiver's distress and burden., Method: This study used self-report survey data from caregivers (N = 96) and a cross-sectional design to examine correlates of caregiver emotional distress and burden. Data collected included caregiver and child demographic data, child symptoms (i.e., sleep problems, pain, and emotional/behavioral problems), caregiver emotional distress, and caregiver burden., Results: Multiple linear regression found that parent reported financial difficulty (β = 0.29, t = 3.13, p = .003), greater child sleep problems (β = 0.29 t = 2.81, p = .007), greater child pain (β = 0.33 t = 3.48, p = .001), and greater child emotional/behavioral problems (β = 0.27, t = 2.71, p = .009) were all related to higher levels of caregiver emotional distress. Only financial difficulties (β = -0.35, t = -2.03, p = .04) and child pain (β = -0.30, t = -2.33, p = .02) were related to caregiver burden., Discussion: Child symptoms may play an important role in the development of caregiver distress and caregiver burden; future research should utilize longitudinal designs to examine temporal and casual relationships. (PsycINFO Database Record, ((c) 2016 APA, all rights reserved).)

Primary Objective: It is well-documented that survivors of paediatric brain tumour are at risk for neurocognitive deficits resulting in an increased interest in neurocognitive assessment for these youth. Given the scarcity of well-validated brief assessments for this purpose, this study examines the reliability and validity of a brief neurocognitive screening measure., Research Design: Cross-sectional data on youth (aged 6-17.9) administered a brief neurocognitive screening device and broader neurocognitive batteries was collected via chart review to evaluate the reliability and validity of a brief neurocognitive screening device., Methods and Procedures: Fifty-one youth with brain tumours and 26 youth with traumatic brain injury (TBI) were administered The Lebby-Asbell Neurocognitive Screening Examination (LANSE) during clinic visits. A sub-set of children were administered a more comprehensive neurocognitive evaluation and scores from the LANSE and these evaluations were compared to assess preliminary validity., Main Outcome and Results: Most LANSE sub-scales demonstrated adequate reliability and preliminary validity with some exceptions. Comparison of youth with brain tumours to those with a TBI revealed a similar pattern of potential neurocognitive impairment across several cognitive domains., Conclusions: This study demonstrates the preliminary reliability and validity of a brief neurocognitive screening examination for youth with brain tumours.

Common variants at many loci have been robustly associated with asthma but explain little of the overall genetic risk. Here we investigate the role of rare (<1%) and low-frequency (1-5%) variants using the Illumina HumanExome BeadChip array in 4,794 asthma cases, 4,707 non-asthmatic controls and 590 case-parent trios representing European Americans, African Americans/African Caribbeans and Latinos. Our study reveals one low-frequency missense mutation in the GRASP gene that is associated with asthma in the Latino sample (P=4.31 × 10(-6); OR=1.25; MAF=1.21%) and two genes harbouring functional variants that are associated with asthma in a gene-based analysis: GSDMB at the 17q12-21 asthma locus in the Latino and combined samples (P=7.81 × 10(-8) and 4.09 × 10(-8), respectively) and MTHFR in the African ancestry sample (P=1.72 × 10(-6)). Our results suggest that associations with rare and low-frequency variants are ethnic specific and not likely to explain a significant proportion of the 'missing heritability' of asthma.

Asthma is a complex disease with sex-specific differences in prevalence. Candidate gene studies have suggested that genotype-by-sex interaction effects on asthma risk exist, but this has not yet been explored at a genome-wide level. We aimed to identify sex-specific asthma risk alleles by performing a genome-wide scan for genotype-by-sex interactions in the ethnically diverse participants in the EVE Asthma Genetics Consortium. We performed male- and female-specific genome-wide association studies in 2653 male asthma cases, 2566 female asthma cases and 3830 non-asthma controls from European American, African American, African Caribbean and Latino populations. Association tests were conducted in each study sample, and the results were combined in ancestry-specific and cross-ancestry meta-analyses. Six sex-specific asthma risk loci had P-values < 1 × 10(-6), of which two were male specific and four were female specific; all were ancestry specific. The most significant sex-specific association in European Americans was at the interferon regulatory factor 1 (IRF1) locus on 5q31.1. We also identify a Latino female-specific association in RAP1GAP2. Both of these loci included single-nucleotide polymorphisms that are known expression quantitative trait loci and have been associated with asthma in independent studies. The IRF1 locus is a strong candidate region for male-specific asthma susceptibility due to the association and validation we demonstrate here, the known role of IRF1 in asthma-relevant immune pathways and prior reports of sex-specific differences in interferon responses., (Published by Oxford University Press 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Aim: We evaluated the prevalence and progression of chronic kidney disease (CKD) during the 5-year period in a cohort of patients with sickle cell disease (SCD) aged 18 years and older., Methods: We studied 98 patients with SCD. Chronic kidney disease stages I through V were defined based on estimated glomerular filtration rate (eGFR), and albuminuria grades were defined based on spot urine protein-to-creatinine ratio according to the 2012 Kidney Disease Improving Global Outcomes recommendations. In patients with eGFR of greater than 60 mL/min per 1.73 m(2), CKD was diagnosed if grade A2 or A3 albuminuria was present. Chronic kidney disease progression was defined as an increase in CKD stage with an additional eGFR reduction of more than 25% from baseline., Results: At baseline, 28.6% of patients had CKD. After a mean follow-up of 5.0 (SD, 0.9) years, 17 patients developed new CKD and the overall CKD prevalence increased to 41.8%. In addition, 8 patients experienced CKD progression. The following baseline variables were associated with the development and progression of CKD in univariate analysis: older age (P = 0.003), higher systolic blood pressure (BP; P = 0.003), lower eGFR (P = 0.001), higher serum creatinine (P = 0.001), and A3 albuminuria (P = 0.008). In multivariate analysis, baseline A3 albuminuria (adjusted odds ratio, 5.0; 95% confidence interval, 1.1-24.3; P = 0.048) and each 1-mm Hg increase in systolic BP (adjusted odds ratio, 1.04; 95% confidence interval, 1.0-1.07; P = 0.039) predicted CKD development and progression., Conclusions: Chronic kidney disease is common in patients with SCD and its prevalence increases with age. Several baseline modifiable and nonmodifiable factors were associated with the development and progression of CKD in patients with SCD. Strategies targeting BP control and proteinuria may be beneficial for individuals with SCD.

Neonatal chondrodysplasia punctata (CDP) is characterized by epiphyseal stippling and midfacial hypoplasia. CDP is usually inherited, but can be acquired because of maternal vitamin K deficiency. We describe an infant with CDP born to a teenager with sickle cell anemia and transfusional iron overload. The mother had severe liver fibrosis, elevated liver iron concentration (34 mg Fe/g), and coagulopathy, but no gestational use of warfarin. Fetal abnormalities were attributed to vitamin K deficiency secondary to liver dysfunction from iron toxicity. Treatment of iron overload among women with sickle cell anemia of childbearing potential is important to avoid possible CDP in newborns.

Background: Maternal asthma and child's sex are among the most significant and reproducible risk factors for the development of asthma. Although the mechanisms for these effects are unknown, they likely involve nonclassical genetic mechanisms. One such mechanism could involve the transfer and persistence of maternal cells to her offspring, a common occurrence known as maternal microchimerism (MMc). MMc has been associated with many autoimmune diseases but has not been investigated for a role in asthma or allergic disease., Objective: We hypothesized that some of the observed risks for asthma may be due to different rates of transmission or persistence of maternal cells to children of mothers with asthma compared with children of mothers without asthma, or to sons compared with daughters. We further hypothesized that rates of MMc differ between children with and without asthma., Methods: We tested these hypotheses in 317 subjects from 3 independent cohorts by using a real-time quantitative PCR assay to detect a noninherited HLA allele in the child., Results: MMc was detected in 20.5% of the subjects (range 16.8%-27.1% in the 3 cohorts). We observed lower rates of asthma among MMc-positive subjects than among MMc-negative subjects (odds ratio, 0.38; 95% CI, 0.19-0.79; P = .029). Neither maternal asthma nor sex of the child was a significant predictor of MMc in the child (P = .81 and .15, respectively)., Conclusions: Our results suggest for the first time that MMc may protect against the development of asthma., (Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Leg ulcers are a debilitating complication of patients with sickle cell disease, and their frequency in North America was reported to be 2.5% by the Cooperative Study of Sickle Cell Disease more than 20 years ago. We sought to determine if the frequency of leg ulcers in sickle cell patients in the United States had declined and to assess which treatments providers use most commonly. We sent an e-mail survey to health professionals belonging to the national Sickle Cell Adult Provider Network. Responses were obtained from 31 of them (26.0%). Most of them (96.0%) reported having some patients with leg ulcers. Providers reported a total of 185 patients with active leg ulcers and 224 in the previous 5 years, for a total of 409 patients. Hb SS (homozygous sickle cell anemia) was the most common genotype of affected individuals, followed by Hb SC (double heterozygote for Hb S [β6(A3)Glu→Val, GAG>GTG; HBB: c.20A>T] and Hb C [β6(A3)Glu→Lys, GAG>AAG; HBB: c.19G>A]). Males showed a 2:1 predominance. Two-thirds of patients were treated with either hydroxyurea (HU) or transfusion therapy and most used compression stockings and topical therapies as directed by wound care services. We conclude that leg ulcers continue to be a debilitating complication of young adults with sickle cell disease, despite improved supportive care and the widespread use of disease modifying agents such HU and transfusion. While some providers offer office-based ulcer care, the majority prefer specialty consultation including podiatry, plastic surgery and dermatology. Despite their frequency, there is no clear consensus among providers as to the best treatment.

Background: Genome-wide association studies of asthma have implicated many genetic risk factors, with well-replicated associations at approximately 10 loci that account for only a small proportion of the genetic risk., Objectives: We aimed to identify additional asthma risk loci by performing an extensive replication study of the results from the EVE Consortium meta-analysis., Methods: We selected 3186 single nucleotide polymorphisms for replication based on the P values from the EVE Consortium meta-analysis. These single nucleotide polymorphisms were genotyped in ethnically diverse replication samples from 9 different studies, totaling 7202 cases, 6426 controls, and 507 case-parent trios. Association analyses were conducted within each participating study, and the resulting test statistics were combined in a meta-analysis., Results: Two novel associations were replicated in European Americans: rs1061477 in the KLK3 gene on chromosome 19 (combined odds ratio = 1.18; 95% CI, 1.10-1.25) and rs9570077 (combined odds ratio =1.20; 95% CI, 1.12-1.29) on chromosome 13q21. We could not replicate any additional associations in the African Americans or Latinos., Conclusions: This extended replication study identified 2 additional asthma risk loci in populations of European descent. The absence of additional loci for African Americans and Latinos highlights the difficulty in replicating associations in admixed populations., (Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Common variation in over 100 genes has been implicated in the risk of developing asthma, but the contribution of rare variants to asthma susceptibility remains largely unexplored. We selected nine genes that showed the strongest signatures of weak purifying selection from among 53 candidate asthma-associated genes, and we sequenced the coding exons and flanking noncoding regions in 450 asthmatic cases and 515 nonasthmatic controls. We observed an overall excess of p values <0.05 (p = 0.02), and rare variants in four genes (AGT, DPP10, IKBKAP, and IL12RB1) contributed to asthma susceptibility among African Americans. Rare variants in IL12RB1 were also associated with asthma susceptibility among European Americans, despite the fact that the majority of rare variants in IL12RB1 were specific to either one of the populations. The combined evidence of association with rare noncoding variants in IL12RB1 remained significant (p = 3.7 × 10(-4)) after correcting for multiple testing. Overall, the contribution of rare variants to asthma susceptibility was predominantly due to noncoding variants in sequences flanking the exons, although nonsynonymous rare variants in DPP10 and in IL12RB1 were associated with asthma in African Americans and European Americans, respectively. This study provides evidence that rare variants contribute to asthma susceptibility. Additional studies are required for testing whether prioritizing genes for resequencing on the basis of signatures of purifying selection is an efficient means of identifying novel rare variants that contribute to complex disease., (Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Asthma is a common disease with a complex risk architecture including both genetic and environmental factors. We performed a meta-analysis of North American genome-wide association studies of asthma in 5,416 individuals with asthma (cases) including individuals of European American, African American or African Caribbean, and Latino ancestry, with replication in an additional 12,649 individuals from the same ethnic groups. We identified five susceptibility loci. Four were at previously reported loci on 17q21, near IL1RL1, TSLP and IL33, but we report for the first time, to our knowledge, that these loci are associated with asthma risk in three ethnic groups. In addition, we identified a new asthma susceptibility locus at PYHIN1, with the association being specific to individuals of African descent (P = 3.9 × 10(-9)). These results suggest that some asthma susceptibility loci are robust to differences in ancestry when sufficiently large samples sizes are investigated, and that ancestry-specific associations also contribute to the complex genetic architecture of asthma.

The commercial feasibility of recombinant human Hb (rHb) as an O(2) delivery pharmaceutical is limited by the production yield of holoprotein in E. coli. Currently the production of rHb is not cost effective for use as a source in the development of third and fourth generation Hb-based oxygen carriers (HBOCs). The major problems appear to be aggregation and degradation of apoglobin at the nominal expression temperatures, 28-37 degrees C, and the limited amount of free heme that is available for holohemoglobin assembly. One approach to solve the first problem is to inhibit apoglobin precipitation by a comparative mutagenesis strategy to improve apoglobin stability. alpha Gly15 to Ala and beta Gly16 to Ala mutations have been constructed to increase the stability of the alpha helices of both subunits of HbA, based on comparison with the sequences of the more stable sperm whale hemoglobin subunits. Fetal hemoglobin is also known to be more stable than human HbA, and sequence comparisons between human beta and gamma (fetal Hb) chains indicate several substitutions that stabilize the alpha1beta1 interface, one of which, beta His116 to Ile, increases resistance to denaturation and enhances expression in E. coli. These favorable effects of enhanced globin stability can be augmented by co-expression of bacterial membrane heme transport systems to increase the rate and extent of heme uptake through the bacterial cell membranes. The combination of increased apoglobin stability and active heme transport appear to enhance holohemoglobin production to levels that may make rHb a plausible starting material for all extracellular Hb-based oxygen carriers.

IL-13 is a central mediator of allergic inflammation. The single nucleotide polymorphism IL13-1112C>T (rs1800925) is associated with allergic phenotypes in ethnically distinct populations, but the underlying mechanism(s) remain unknown. Using in vivo, in vitro, and in silico analysis, we show that the IL13-1112T allele enhanced IL13 promoter activity in primary human and murine CD4(+) Th2 lymphocytes. Increased expression of IL13-1112T in Th2 cells was associated with the creation of a Yin-Yang 1 binding site that overlapped a STAT motif involved in negative regulation of IL13 expression and attenuated STAT6-mediated transcriptional repression. Because IL-13 secretion was increased in IL13-1112TT homozygotes, we propose that increased expression of IL13-1112T in vivo may underlie its association with susceptibility to allergic inflammation. Interestingly, IL13-1112T had opposite transcriptional effects in nonpolarized CD4(+) T cells, paralleled by distinct patterns of DNA-protein interactions at the IL13 promoter. Our findings suggest the nuclear milieu dictates the functional outcome of genetic variation.

Background: The T-cell immunoglobulin domain and mucin domain (TIM) gene family and the gene for IL-2-inducible T-cell kinase (ITK), located in chromosome 5 q 33 and potentially involved in the T-cell proliferation and differentiation, are good candidate genes for allergic diseases., Objective: We assessed the role of polymorphisms in the TIM family genes and ITK in atopy, eczema, and asthma., Methods: Twenty-one polymorphisms in the TIM-ITK gene cluster were genotyped in 564 children enrolled in the Tucson Children's Respiratory Study. Skin prick tests to common allergens were performed at age 6.1 years (n=508), age 10.8 years (n=539), and age 16.6 years (n=424). Asthma and eczema were assessed by questionnaire at these 3 points. Averaged relative risks were estimated., Results: One 15-bp insertion/deletion in exon 4 of TIM 1 was significantly related to atopy and eczema (relative risk associated with carrying at least 1 rare allele=1.24 [1.07--1.45], P=.005; and 1.43 [1.01--2.01], P=.004, respectively). The 3 tested single nucleotide polymorphisms (SNPs) in TIM 3 were significantly related to atopy and eczema. One of them, at position +4259 calculated from the translation start site, predicts a putative change in the amino acid sequence of the protein, and was the most strongly related to atopy (relative risk=1.28 [1.12--1.47]; P=.0003). SNPs in the 5' genomic region in ITK, which show moderate linkage disequilibrium with those in TIM 3, had an independent effect on atopy. None of the polymorphisms studied was related to asthma., Conclusion: Our findings support a potential role for SNPs in TIM 1, TIM 3, and ITK, independent of each other, in allergic diseases.

This paper offers a model for the bias found in willingness-to-pay valuations against new treatments. For example, this bias provides an explanation for patient preferences that make it difficult for formularies to take treatments off their lists, even when newer treatments would appear to be clearly preferable. The appeal of the model, which is based on imperfect information, is that it is consistent with rational preferences and rational behavior by patients, which are necessary for standard models and methods related to decision theory, cost-effectiveness, and efficiency.

Background: A variety of definitions of asthma and atopy traits have been used in genetic studies. The variables used may be correlated, increasing the likelihood of type I error., Objective: We sought to clarify and quantify phenotypes that may be characterized by related traits. Principal components and factor analysis were applied to the correlation matrix of asthma and atopy traits before linkage analysis., Methods: Factor analysis was performed on 468 Hispanic and non-Hispanic white children enrolled in the Tucson Children's Respiratory Study, with complete information on 24 items, including skin test response to 7 allergens, total serum IgE levels, presence or absence of asthma attacks, wheezing episodes, hay fever, and cough. Factor score coefficients were then applied to all siblings (n = 877), and quantitative factor scores were derived. Single-point and multipoint nonparametric sib-pair analyses were performed to assess linkage to markers on chromosome 5q31-33. Analyses were also performed for individual items., Results: Two main factors were identified: Factor I had high loadings on atopic items, including skin test responses, IgE, and hay fever, and Factor II had high loadings that included asthma diagnosis, wheezing, cough, and Alternaria species skin test response. Factors I and II were correlated at an r value of 0.19. For the quantitative factor scores, significant single-point linkage (P < .0001) was demonstrated only for atopic Factor I, and a peak multipoint LOD score of 2.7 was seen for marker D5S479. Multipoint LOD scores for individual items were 1.1 or less., Conclusion: These analyses suggest evidence for a locus or loci mapping to chromosome 5q31-33 associated with this composite atopic phenotype.

Background: Increased levels of total serum IgE are a strong risk factor for the development of asthma. IgE is also involved in host defenses against parasites and fungi. Linkage of total serum IgE with markers located close to the 3 Mb cluster of cytokine genes in chromosome 5q31 has been reported. IL-4 or IL-13 are regarded as essential for IgE synthesis., Objective: We tested whether polymorphisms in the IL-13 gene might explain the linkage between chromosome 5q31 and total serum IgE levels., Methods: We used denaturing HPLC to detect polymorphisms in overlapping PCR fragments of the IL-13 gene including promoter and 3' untranslated regions. After sequencing was performed to identify the locations of the polymorphisms, PCR and primer-induced restriction site assays were used to genotype subjects in 3 unselected populations., Results: We report here 7 polymorphisms (6 novel) in IL-13. Four of these polymorphisms are tightly linked to a variant in the terminal portion of the coding region of the gene that results in a predicted amino acid change in residue 130 (Arg130Gln). The Gln form is strongly associated (P =.000002) with increased serum IgE levels in 3 different populations comprising a total of 1399 children. Two additional polymorphisms in the promoter region of IL-13 are more loosely linked to Arg130Gln and are also less significantly associated with total serum IgE levels., Conclusion: These data suggest that the Arg130Gln polymorphism in IL-13, or others in close linkage with it, is associated with the development of the elevated serum IgE phenotype.

Although peripheral blood eosinophilia is strongly associated with the risk of developing asthma, genetic determinants of eosinophilia have not been extensively studied. We used sib-pair analysis to assess linkage of circulating eosinophils (as a percent of total white blood cells [WBC]) to nine markers located in chromosome 5q31-33. The study was divided into two phases. Of 246 sib pairs available for the first phase, 35 were classified as low concordant (LC) (both sibs had <= 2% circulating eosinophils), 18 were defined as high concordant (HC) (both sibs had 5% or more circulating eosinophils), and 26 were defined as discordant (one sib had <= 2% and the other sib had 5% or more circulating eosinophils). Significant evidence for linkage among low concordant sib pairs was found for several markers in the region under study, with a peak for marker D5S500 (proportion of alleles shared identical by descent [ibd] = 0.68 +/- 0.05 [mean +/- SE], p = 0.0004). A cross-validating study was done in which an additional 19 sib pairs that were low concordant for circulating eosinophils were studied. Evidence for linkage was also observed in this subset. Results were independent of current wheezing, total serum IgE levels, and other potential confounders. A multipoint analysis done for all low-concordant sib pairs available showed that the maximal logarithm of the odds favoring genetic linkage (LOD) score (2.4, p = 0.0004) was observed in correspondence with marker D5S658. We conclude that a locus or loci may be present in chromosome 5q31-33 that controls for circulating eosinophils as a proportion of total WBC.

The beta2-adrenergic receptor (beta2AR) agonists are the most widely used agents in the treatment of asthma, but the genetic determinants of responsiveness to these agents are unknown. Two polymorphic loci within the coding region of the beta2AR have been recently described at amino acids 16 and 27. It has been reported that glycine at codon 16 (Gly-16) is associated with increased agonist-promoted downregulation of the beta2AR as compared with arginine-16 (Arg-16). The form of the receptor with glutamic acid at codon 27 (Glu-27), on the other hand, has been shown to be resistant to downregulation when compared with glutamine-27 (Gln-27), but only when coexpressed with Arg-16. To assess if different genotypes of these two polymorphisms would show differential responses to inhaled beta2AR agonists, we genotyped 269 children who were participants in a longitudinal study of asthma. Spirometry was performed before and after administration of 180 microg of albuterol, and a positive response was considered an increase of >15.3% predicted FEV1. There was marked linkage disequilibrium between the two polymorphisms, with 97.8% of all chromosomes that carried Arg-16 also carrying Gln-27. When compared to homozygotes for Gly-16, homozygotes for Arg-16 were 5.3 times (95% confidence interval 1.6-17.7) and heterozygotes for beta2AR-16 were 2.3 times (1.3-4.2) more likely to respond to albuterol, respectively. Similar trends were observed for asthmatic and nonasthmatic children, and results were independent of baseline lung function, ethnic origin, and previous use of antiasthma medication. No association was found between the beta2AR-27 polymorphism and response to albuterol. These results may explain some of the variability in response to therapeutic doses of albuterol in children.

A complementary DNA clone encoding a functional receptor for prostaglandin F2 alpha (PGF2 alpha) has been isolated from an ovine large luteal cell complementary DNA library (prepared from day 10 mid-luteal phase RNA). This receptor, which has been designated FP, consists of 362 amino acids (M(r) = 40,982) and is a member of the family of G protein-coupled receptors. Radioligand binding studies with membranes prepared from transfected COS cells demonstrated specific 17-[3H]phenyl-trinor-PGF2 alpha binding that was displaced by prostanoids in the order of 17-phenyl-trinor-PGF2 alpha > PGF2 alpha > fluprostenol > PGD2 > PGE2 >> 8-epi PGF2 alpha. Xenopus laevis oocytes injected with RNA encoding the ovine FP receptor responded to 17-phenyl-trinor-PGF2 alpha with increased membrane chloride conductance in calcium-free medium. Northern blot analysis with RNA from day 10 corpus luteum showed a major band of approximately 6.1 kilobases. On day 14, when luteolysis usually starts, the abundance of this 6.1-kilobase band was variable between individual ewes, and on day 16, when luteolysis is underway, the message was uniformly less abundant. This variability appeared to correlate with circulating progesterone. Thus, when the progesterone level was high (days 10 and 14 depending on whether luteolysis had started), the amount of FP receptor message was high, whereas when the progesterone level was low or falling (day 16), the amount of FP receptor message decreased. We have cloned an ovine FP receptor whose expression confers appropriate functional activity in COS cells and Xenopus oocytes. Furthermore, the level of messenger RNA encoding the FP receptor is high in the midluteal phase ovine corpus luteum and decreases during luteolysis.

Sry is the testes determining factor gene located on the Y chromosome. We sought sequence variation in potential promoter regions that might explain the gradiation in sex reversal seen when different domesticus strains are bred to C57BL/6J females since sequence variation previously found in the coding region is not sufficient to explain it. Dideoxy sequencing identified a 10 bp deletion in the 5' flanking region limited to YDOM chromosomes of weak effect. A PCR strategy to search for deletions in this region disclosed another deletion which was shown to be different by sequencing.

We have studied the metabolism of compounds containing 31P in normal breast using magnetic resonance spectroscopy (MRS). Spectra were acquired from non-lactating pre-menopausal breast (n = 14 women), lactating breast (n = 8) and post-menopausal breast (n = 8). The standard acquisition protocol used a 5.5 cm surface coil with the volunteer prone to minimize chest wall signal contamination. In pre-menopausal non-lactating women the phosphocreatine (PCr) peak area, expressed relative to the sum of all 31P peak areas, was negatively correlated with breast size (r = -0.56, p = 0.02) suggesting that much of the PCr signal originated from the chest wall. The phosphodiester (PDE) relative peak area was positively correlated with breast size (r = 0.71; p = 0.002). Spectra could be acquired at all phases of the menstrual cycle. In sequential examinations of five women not taking the oral contraceptive pill (OCP), phosphomonoester (PME) relative peak area was significantly lower on Week 2 than other weeks of the cycle (p = 0.03). Among pre-menopausal women no clear difference was apparent between the spectra from women taking the OCP and those not taking the OCP. Lactating breast had significantly higher PME relative peak area than non-lactating pre-menopausal breast (p = 0.02), probably reflecting the higher proportion of epithelial tissue in lactation; the lower PCr relative peak area in lactating breast (p = 0.05) is probably due to the greater size of the breast during lactation. Spectra were acquired from post-menopausal women but with a relatively low signal-to-noise ratio. The only significant difference between 31P relative peak areas of breast spectra acquired from pre- and post-menopausal women was that less PCr was detected in the post-menopausal volunteers (p = 0.03), probably as a result of differences in breast size.

The authors critically examine a 1990 study by Alan W. Evans concerning the assumption of interregional equilibrium in recent migration research. "We here argue that Evans is unconvincing in his primary substantive argument; we provide an alternative reading of the literature that supports this assertion....[We then illustrate] the substantive issues in terms of a simple formal model that allows for both equilibrium and disequilibrium migration." The geographical focus is on the United States. A reply by Evans is included (pp. 89-97)., (excerpt)

Sry is the testes determining factor gene located on the Y chromosome. We have performed dideoxy sequencing or restriction enzyme digestion of Sry sequences amplified by PCR from a variety of inbred strains and species of mice. A nonconservative replacement of Thr for Isoleu at position 61 was found in Sry from the Y chromosome of Mus musculus domesticus, Mus spretus, and Mus caroli. We demonstrate that this variation is not sufficient to explain the gradiation in the sex-reversal seen when different domesticus strains are bred to C57BL/6J females.

Dural sinus thrombosis can be a difficult diagnosis to establish because it may present with nonspecific signs of raised intracranial pressure. Diagnosis by CT is well documented but signs may be subtle. Angiography is the "gold standard" but is invasive and requires a very high index of clinical suspicion to request. Magnetic resonance offers a method of demonstrating the dural sinuses in multiple planes and, furthermore, flow within the sinuses may be depicted by MR angiography. We report on three cases where the diagnosis of superior sagittal sinus thrombosis due to calvarial metastases was missed by CT, primarily due to their site over the convexity, but was demonstrated accurately using MR with MR angiography.

A 1.96 kbp cDNA encoding a male Beagle dog liver cytochrome P-450 of 503 amino acid residues (Mr 57,636) has been isolated and sequenced. The deduced amino acid sequence is 79.8%, 69.3% and 74.1% identical to the P450IIIA forms human NF25, rat PCN1 and rabbit LM3c, respectively. The amino terminal sequence is identical to the first 28 residues of the dog P450IIIA form PBD-1. Southern blot analysis yields restriction patterns consistent with IIIA gene subfamily multiplicity.

The nucleotide sequence of a cDNA that codes for the major phenobarbital (PB)-inducible male beagle dog hepatic cytochrome P450 has been determined. Using a rabbit P450IIB cDNA probe (R. Gasser, M. Negishi, and R. M. Philpot, 1988, Mol. Pharmacol, 32, 22-30), a cDNA clone with a 2.6-kilobase pair insert was isolated from a lambda gt11 library prepared from hepatic mRNA from a PB-treated dog. The cloned insert was sequenced and found to contain an open reading frame coding for a polypeptide of 494 amino acids (Mr 56,183). The encoded protein can be assigned to the P450IIB subfamily on the basis of homology to cytochromes P450 from other species. The deduced amino acid sequence is 79% identical to that reported for rabbit P450 BO (P450IIB4) and 75% identical to that for rat P450b (P450IIB1). The sequence identity decreases to less than 52% when the dog sequence is compared with other P450II subfamilies. The deduced NH2-terminal 30 amino acids encoded by the dog cDNA are identical to those determined by sequence analysis of purified dog cytochrome P450 PBD-2, and the amino acid composition concurs with that determined for the PBD-2 protein (D. B. Duignan, I. G. Sipes, T. B. Leonard, and J. R. Halpert, 1987, Arch. Biochem. Biophys. 255, 290-303). Northern blots revealed two mRNA species of approximately 1.9 and 2.9 kilobases in length, which hybridized to the coding region of the dog P450IIB cDNA. The level of total hybridizable mRNA was increased approximately sixfold in livers from PB-treated dogs compared with that in untreated animals. This increase correlates well with the reported nearly sixfold increase in the level of PBD-2 protein and the fivefold increase in the rate of hepatic metabolism of 2,2',4,4',5,5'-hexachlorobiphenyl following PB treatment. The two mRNA species may result from the use of different polyadenylation signals located in the 3'-noncoding region or from transcription of more than one gene for PBD-2. Southern blot analysis indicated that the dog P450IIB subfamily contains at least two closely related genes.

Digoxin serum concentration rises in the presence of quinidine. To determine whether quinidine alters digoxin bioavailability, six subjects received 1.0 mg of digoxin intravenously alone and by mouth on alternate weeks during steady-state oral quinidine administration. The area under the digoxin concentration:time curves (AUC) and the amount of digoxin excreted in the urine (Xxu) were determined for the 96 hr after each of the four experiments. Values for digoxin bioavailability relative to the corresponding intravenous study in the absence and presence of quinidine were (+/- S.D.) 73.5 +/- 8.6% and 79.5 +/- 22.6% (P greater than 0.05) for serum and 69.8 +/- 6.8% and 70.2 +/- 10.5% (P greater than 0.05) for urine. There was no difference in the steady-state quinidine serum concentration during the 4 days after intravenous and oral digoxin. We conclude that quinidine does not alter digoxin bioavailability and therefore that altered absorption does not explain the rise in digoxin serum concentration in the presence of quinidine.

The effect of quinidine on digitoxin single-dose pharmacokinetics was evaluated in five healthy adults. Blood was collected for 3 weeks, and a complete urine collection was obtained for 4 days, after a single intravenous dose of digitoxin. The protocol was conducted once while each subject was taking oral quinidine, for 3 weeks, and then repeated 10 days after discontinuing quinidine treatment. Quinidine induced the following changes in digitoxin pharmacokinetics: Elimination half-life was prolonged from 174 +/- 25 to 261 +/- 58 hours (p less than 0.02); total body clearance decreased from 1.54 +/- 0.40 to 1.09 +/- 0.31 mL/h . kg (p less than 0.05); renal clearance decreased from 0.65 +/- 0.07 to 0.46 +/- 0.17 mL/h . kg (p less than 0.05). Digitoxin volume of distribution and protein binding were unaltered by quinidine. Quinidine caused a rise in serum digitoxin levels. Digitoxin total body clearance was decreased by quinidine to an extent comparable to that reported for digoxin; however, the mechanism of the interaction with the two digitalis glycosides may, in part, be different.

The pharmacokinetic behavior of digitoxigenin is affected by the number of glycosides present. This study was conducted to compare the bioavailabilities of the bis- and monodigitoxosides of digitoxigenin in man. Intravenous and oral doses of the two drugs were administered to six normal volunteers. Blood samples were collected up to 28 days after each dose, and assayed for the specific drug administered and for total radioassayable drug. Both drugs were virtually completely absorbed, based on serum concentrations of administered drug plus metabolites. However, the mean bioavailability of unchanged bisdigitoxoside was only 56.3% indicating that substantial metabolism occurred prior to entry into the systemic circulation. Monodigitoxoside was virtually completely metabolized prior to entry into the systemic circulation.

A specific assay is described for measuring the concentration of digitoxin and the bis- and monoglycosides of digitoxigenin in serum. The procedure includes: (1) addition of a tracer amount of tritium labeled parent compound to the serum in order to measure percentage recovery; (2) solvent extraction to separate polar and non-polar metabolites; (3) reversed-phase thin-layer chromatography of the non-polar fraction to separate digoxigenins from digitoxigenins; (4) thin-layer chromatography to isolate digitoxin, and the bis- and monoglycosides of digitoxigenin; and (5) use of an 125I-radioimmunoassay to determine the concentration of the glycosides. Each of these three glycosides was administered intravenously to a normal subject, and the concentration of parent compound was measured in the serum at various times.

The relevance of concepts of equilibrium to the analysis of migration between Mexico and the United States is examined. A theoretical model applicable to this type of international migration is first developed. The next section "presents some limited and tentative empirical observations and suggests the knowledge which might be needed for a more precise understanding of the utility differentials between countries which give rise to migration, legal or illegal." A final section is devoted to the policy implications of this approach to migration analysis., (excerpt)

A multinomial logit model of residence and job change is developed and estimated using U.S. data from the Michigan Panel Study of Income Dynamics. It is found that both housing demand and job search characteristics are significant determinants of the decision to migrate and that both equilibrium and disequilibrium forces induce migration and job change. In addition, "the data do not appear to be ordered with respect to job and residence change contingencies with the exception of changing neither job nor residence relative to all other contingencies.", (excerpt)

"Various disciplines have produced models to explain and predict human migration. A model is presented providing a taxonomy through which interdisciplinary insights can be synthesized. The imperfect information view emphasizes the role of wage differentials as representing arbitragible real utility differentials. The perfect information approach holds that wage and rent differentials are compensating differentials, eliminating real utility variation over space.... Empirical results [for the United States] are presented which support the latter equilibrium view.... The increasing relative importance of amenities as a determinant of migration [is suggested].", (excerpt)

The dextrorotatory enantiomer of aminoglutethimide is 38 times more potent than the levoenantiomer in inhibiting aromatization of testosterone by human placental microsomes. The spectral affinity constant for microsomal cytochrome P-450 is 36 times greater for the d-enantiomer. Enzymatic inhibition and affinity are highly correlated for each of the isomers as well as for the racemic mixture. Spectral analysis of the interactions of the inhibitors with the substrate supports the evidence for participation of cytochrome P-450 in aromatization.

We evaluated the effect of quinidine on digoxin pharmacokinetic in six patients with severe renal failure. Quinidine reduced the total body clearance of digoxin from 1.87 to 1.06 l/hour (p less than 0.001), and prolonged the digoxin half-life of elimination from 5.20 to 9.61 days (p less than 0.01). The digoxin volume of distribution was unchanged. Renal clearance of digoxin was negligible; thus, the decrease in total body clearance was due to a decrease in the nonrenal clearance of digoxin. The mean trough serum concentrations of quinidine ranged from 1.0 to 3.0 micrograms/ml. We conclude that in patients with chronic renal failure, the dose of digoxin should be decreased by 50% if quinidine therapy is initiated.

Absorbance changes in the spectrum of cytochrome P-450 were related to the inhibition of [26-14C]cholesterol oxidation to [14C]isocaproate and pregnenolone in mitochondria from bovine corpus luteum produced by two types of ligands. Nitrogenous inhibitors, such as aminoglutethimide, elicit an absorption maximum at about 427 nm and a minimum at about 393 nm (type II), while steroidal inhibitors, such as (20R)-20-(p-tolyl)-5-pregnene-3beta,20-diol (20-tolyl-pregnenediol), cause difference spectra with maximum at about 420 nm and minimum at about 390 nm (reverse type I). The magnitude of spectral change and the amount of inhibition of pregnenolone synthesis by aminoglutethimide are closely correlated at concentrations ranging from 5 to 750 muM and by the model steroid, 20-tolyl-pregnenediol, at concentrations from 0.5 to 25 muM. The responses are concentration dependent and linear over the range of effective concentrations. The concentrations of inhibitors for the half-maximal inhibition of pregnenolone biosynthesis are identical with the concentrations producing half-maximal spectral changes within experimental error. Displacement of substrate from cytochrome P-450 and/or stabilization of the redox potential subsequent to to the ligation of heme iron is proposed as the specific mechanism of cholesterol side chain cleavage inhibition. Finding, together, the two procedures offer a sensitive, specific, and accurate means of screening inhibitors of the cholesterol side chain cleavage system.

Several groups of compounds were tested for their ability to inhibit cholesterol side chain cleavage and induce spectral change in cytochrome P-450 from bovine corpus luteum, bovine adrenal cortex, and human placental mitochondria. The substances tested include: steroids, pyridines, glutarimides, anilines and imidazoles. Good correlation was found between spectral change and enzymatic inhibition, especially in the corpus luteum which has only a single P-450-linked steroid hydroxylase. The cholesterol side chain cleavage enzyme systems from each of the three sources appear to have similar affinities for the inhibitors, which adds further support to the concept that these cytochrome P-450s are functionally identical.

The purpose of this study was to determine if there is a linear relationship between oral doses of digoxin and various measurements of steady-state digoxin plasma concentration and urinary excretion in patients with wide range of renal function. Ten patients (mean age 58 years) with creatinine clearances greater than 50 ml/min/1.73 m2 BSA (mean creatinine clearance 80 ml/min/1.73 m2 BSA) and nine patients mean age 61 years) with creatinine clearances less than 50 ml/min/1.73 m2 BSA (mean creatinine clearance 20 ml/min/1.73 m2 BSA) were given digoxin tablets orally at two or three different dose levels (dose range 0.0313--0.5 mg/day). After a dosing period equal to at least five half-lives, three to four consecutive daily digoxin plasma concentrations were determined. Plasma concentrations and urinary digoxin excretion were measured during one 24-hour dosing interval at each dose level. Digoxin plasma and urine concentrations were determined in triplicate using radioimmunoassay. Individual patient plots provided evidence of linearity for: digoxin 24-hour steady-state plasma concentration vs dose; digoxin 24-hour cumulative urinary excretion versus dose; and area under the digoxin plasma concentration-time curve during a 24-hour dosing interval vs dose. Absolute values for these various parameters indicated substantial interpatient variation probably due to patient differences in both digoxin absorption and digoxin total body clearance. These results indicate that there is a linear relationship between digoxin plasma concentration and dose in patients with normal and decreased renal function. This linearity is support for dose-independent pharmacokinetics of digoxin in man. We conclude from these data that a change in digoxin dose should result in a proportional change in digoxin plasma concentration over the dose range examined.

Six subjects were evaluated for the effect of quinine, the l-isomer of quinidine, on digoxin pharmokinetics. A 1.0-mg intravenous digoxin dose was given before and during quinine administration, followed by the measurement of digoxin serum and urine concentrations for 96 hr after each dose. Quinine reduced digoxin total body clearance by 26% from 2.98 to 2.22 ml/min/kg (p < 0.03). Digoxin elimination half-life (t 1/2) was lengthened from 34.2 to 51.8 hr, reflecting a 32% decrease in digoxin elimination rate constant (p < 0.003). Quinine did not reduce digoxin renal clearance or any volumes of distribution. The amount of digoxin excreted into the urine increased from x = 628. 29 micrograms to x = 772.52 micrograms (p < 0.02). Digoxin nonrenal clearance decreased an average of 55% from 1.2 to 0.55 ml/min/kg (p < 0.05). These results suggest that quinine alters digoxin metabolism or biliary secretion, reducing digoxin total body clearance by a mechanism that is qualitatively similar, but quamtitatively different, from quinidine.