bluuebunny/crossref_metadata_2025 huggingface dataset:
Phase III Study of R-CVP Compared With Cyclophosphamide, Vincristine, and Prednisone Alone in Patients With Previously Untreated Advanced Follicular Lymphoma
Authors: Marcus Robert , Imrie Kevin , Solal-Celigny Philippe , Catalano John V. , Dmoszynska Anna , Raposo João C. , Offner Fritz C. , Gomez-Codina José , Belch Andrew , Cunningham David , Wassner-Fritsch Elisabeth , Stein George
Published: July 2008

Purpose

To compare the long-term outcome of patients with previously untreated follicular lymphoma (FL) needing therapy, after treatment with cyclophosphamide, vincristine and prednisone (CVP) versus CVP plus rituximab (R-CVP) and to evaluate the predictive value of known prognostic factors after treatment with R-CVP.

Patients and Methods

Patients with previously untreated CD20-positive stage III/IV FL were randomly assigned to eight cycles of R-CVP (n = 159) or CVP alone (n = 162). The median follow-up period was 53 months.

Results

The primary end point—time to treatment failure (TTF), which included patients without a response after four cycles as an event—was significantly prolonged in patients receiving R-CVP versus CVP (P < .0001). Improvements in all other end points, including overall and complete response rates (P < .0001), time to progression (TTP; P < .0001), response duration (P < .0001), time to next antilymphoma treatment (P < .0001), and overall survival (OS; P = .029; 4-year OS: 83% v 77%;) were achieved with R-CVP versus CVP alone. Univariate analyses demonstrated an improvement in TTP with R-CVP versus CVP irrespective of the Follicular Lymphoma International Prognostic Index (FLIPI) subgroup, the International Prognostic Index (IPI) subgroup, baseline histology, and the presence or absence of B symptoms or bulky disease. By multivariate analysis, FLIPI retains a strong predictive power for TTP in the presence of the trial treatment effect.

Conclusion

Analysis of all outcome measures, including OS, confirm the benefit of adding R to CVP in the front-line treatment of FL.
Addition of Rituximab to Standard Chemotherapy Improves the Survival of Both the Germinal Center B-Cell–Like and Non–Germinal Center B-Cell–Like Subtypes of Diffuse Large B-Cell Lymphoma
Authors: Fu Kai , Weisenburger Dennis D. , Choi William W.L. , Perry Kyle D. , Smith Lynette M. , Shi Xinlan , Hans Christine P. , Greiner Timothy C. , Bierman Philip J. , Bociek R. Gregory , Armitage James O. , Chan Wing C. , Vose Julie M.
Published: July 2008

Purpose

Diffuse large B-cell lymphoma (DLBCL) includes at least two prognostically important subtypes (ie, germinal center B-cell–like [GCB] and activated B-cell–like [ABC] DLBCL), which initially were characterized by gene expression profiling and subsequently were confirmed by immunostaining. However, with the addition of rituximab to standard chemotherapy, the prognostic significance of this subclassification of DLBCL is unclear.

Patients and Methods

We studied 243 patient cases of de novo DLBCL, which included 131 patient cases treated with rituximab plus standard chemotherapy (rituximab group) and 112 patient cases treated with only standard chemotherapy (control group). The cases were assigned to GCB or non-GCB subgroups (the latter of which included both ABC DLBCL and unclassifiable DLBCL) on the basis of immunophenotype by using the Hans method. Clinical characteristics and survival outcomes of the two patient groups were compared.

Results

The clinical characteristics of the patients in the rituximab and the control groups were similar. Compared with the control group, addition of rituximab improved the 3-year overall survival (OS; 42% v 77%; P < .001) of patients with DLBCL. Rituximab-treated patients in either the GCB or the non-GCB subgroups also had a significantly improved 3-year OS compared with their respective subgroups in the control group (P < .001). In the rituximab group, the GCB subgroup had a significantly better 3-year OS than the non-GCB subgroup (85% v 69%; P = .032). Multivariate analyses confirmed that rituximab treatment was predictive for survival in both the GCB and the non-GCB subgroups.

Conclusion

In this retrospective study, we have shown that the subclassification of DLBCL on the basis of the cell of origin continues to have prognostic importance in the rituximab era.
Effect of Molecular Disease Subsets on Disease-Free Survival in Randomized Adjuvant Chemotherapy Trials for Estrogen Receptor–Positive Breast Cancer
Authors: Pusztai Lajos , Broglio Kristine , Andre Fabrice , Symmans W. Fraser , Hess Kenneth R. , Hortobagyi Gabriel N.
Published: July 2008

Purpose

The majority of estrogen receptor (ER)–positive cancers are sensitive to endocrine therapy and may not derive much further benefit from chemotherapy, but a subset are potentially chemotherapy sensitive. Molecular diagnostic tests allow the identification of these various subsets with some accuracy. The goal of the current analysis was to examine how the proportion of cases in the various risk (recurrence score [RS]) categories of a commercially available multigene assay influences the power of randomized trials to show benefit from adjuvant chemotherapy.

Methods

We modeled 10-year disease-free survival (DFS) for hypothetical, two-arm clinical trials that randomly assigned patients with ER-positive breast cancer to endocrine therapy alone or endocrine therapy plus chemotherapy. We varied the proportion of patients in low, intermediate, and high RS categories and used DFS estimates for each risk group based on results from the Southwest Oncology Group 8814 study.

Results

The probability of observing significant improvement in DFS as a result of chemotherapy decreases as the proportion of patients in the low RS category increases. For example, if a trial is designed with 80% power and the actual proportion of low RS patients accrued to the study increases from 40% to 60%, the power drops to 63%.

Conclusion

Variable accrual of low RS patients into different randomized adjuvant chemotherapy trials may partly explain contradictory results in the literature. Studies can be underpowered to detect improvement with chemotherapy as a result of inclusion of too many patients with low RS. Future adjuvant studies for ER-positive breast cancer will need to consider stratifying patients by molecular subtype.
The effectiveness of parental communication in modifying the relation between food advertising and children's consumption behaviour
Authors: Buijzen Moniek
Published: July 2008

The aim of this study was to examine the effectiveness of various types of parental communication in modifying children's responses to television food advertising. In a combined diary‐survey study among 234 parents of 4‐ to 12‐year‐old children, I investigated how different styles of advertising mediation (active vs. restrictive) and consumer communication (concept‐oriented vs. socio‐oriented) moderated the relation between children's advertising exposure and their consumption of advertised energy‐dense food products. Interaction analysis in regression showed that active advertising mediation (i.e. explaining the purpose and nature of advertising), and socio‐oriented consumer communication (i.e. emphasizing control and restrictions) significantly reduced the impact of advertising on children's food consumption. Parental restrictions of advertising exposure were only effective among younger children (<8). These results suggest that critical discussion about advertising and rule making about consumption are most effective in countering the impact of food advertising.
Generativity and imagination in autism spectrum disorder: Evidence from individual differences in children's impossible entity drawings
Authors: Low Jason , Goddard Elizabeth , Melser Joseph
Published: July 2008

This study examined the cognitive underpinnings of spontaneous imagination in autism spectrum disorder (ASD) by way of individual differences. Children with ASD (N=27) and matched typically developing (TD) children were administered Karmiloff‐Smith's (1990) imaginative drawing task, along with measures that tapped specific executive functions (generativity, visuospatial planning, and central coherence processing style) and false belief theory of mind (ToM) understanding. The ASD group drawings displayed deficits in imaginative content and a piecemeal pictorial style. ASD participants also showed group deficits in generativity, planning and ToM, and exhibited weak coherence. Individual differences in generativity were related to imaginative drawing content in the ASD group, and the association was mediated through planning ability. Variations in weak coherence were separately related to a piecemeal drawing style in the ASD group. Variations in generativity were also linked with imaginative drawing content in the TD group; the connection unfolded when it received pooled variance from receptive language ability, and thereupon mediated through false belief reasoning to cue imaginative content. Results are discussed in terms of how generativity plays a broad and important role for imagination in ASD and typical development, albeit in different ways.
Establishing a Reference Interval for Bone Turnover Markers in 637 Healthy, Young, Premenopausal Women From the United Kingdom, France, Belgium, and the United States
Authors: Glover Sarah J , Gall Martin , Schoenborn-Kellenberger Oliver , Wagener Michael , Garnero Patrick , Boonen Steven , Cauley Jane A , Black Dennis M , Delmas Pierre D , Eastell Richard
Published: July 2008

Robust reference intervals are needed for the interpretation of bone turnover markers in large phase III fracture trials. The objectives of the study were to (1) estimate reference intervals for serum bone alkaline phosphatase (bone ALP), serum procollagen type I N propeptide (PINP), serum β cross-linked C-telopeptides of type I collagen (S-βCTX), and urinary cross-linked N-telopeptides of type I collagen (U-NTX) in healthy young premenopausal women; (2) examine geographical differences on bone turnover markers; and (3) assess factors known to influence bone turnover and test whether these explain any regional differences. We studied 637 eligible women from four countries that participated in the Horizon-PFT study (United Kingdom, France, Belgium, United States). The women were 30–39 yr of age (mean, 34.6 yr), with regular cyclic menses. Subjects completed a medical and lifestyle questionnaire. Two-sided 95% reference intervals were estimated on transformed values and transformed back to the original scale using the proposed methodology of the International Federation of Clinical Chemistry. S-βCTX was significantly higher in France relative to the United Kingdom (p = 0.01), and PINP was higher in France (p < 0.001) and Belgium (p = 0.02) relative to the United Kingdom and significantly higher in France relative to the United States (p < 0.01) by ANOVA. Overall, one could associate low bone turnover markers with nonsmoking, use of a contraceptive pill, exercise, being close to the time of ovulation, and having high 25-hydroxyvitamin D levels. Countries differed by these characteristics, and once allowed for in the statistical model, any country differences were attenuated or removed.
High-Resolution pQCT Analysis at the Distal Radius and Tibia Discriminates Patients With Recent Wrist and Femoral Neck Fractures
Authors: Vico Laurence , Zouch Mohamed , Amirouche Adel , Frère Delphine , Laroche Norbert , Koller Bruno , Laib Andres , Thomas Thierry , Alexandre Christian
Published: July 2008

We depict a fragility bone state in two primitive osteoporosis populations using 3D high-resolution peripheral in vivo QCT (HR-pQCT). Postmenopausal women (C, controls, n = 54; WF, wrist, n = 50; HF, hip, n = 62 recent fractured patients) were analyzed for lumbar and hip DXA areal BMD (aBMD), cancellous and cortical volumetric BMD (vBMD), and microstructural and geometric parameters on tibia and radius by HR-pQCT. Principal component analysis (PCA) allowed extracting factors that best represent bone variables. Comparison between groups was made by analysis of covariance (ANCOVA). Two factors (>80% of the entire variability) are extracted by PCA: at the radius, the first is a combination of trabecular parameters and the second of cortical parameters. At the tibia, we found the reverse. Femoral neck aBMD is decreased in WF (8.6%) and in HF (18%) groups (no lumbar difference). WF showed a ∼20% reduction in radius trabecular vBMD and number. Radius cortical vBMD and thickness decrease by 6% and 14%, respectively. At the tibia, only the cortical compartment is affected, with ∼20% reduction in bone area, thickness, and section modulus and 6% reduction in vBMD. HF showed same radius trabecular alterations than WF, but radius cortical parameters are more severely affected than WF with reduced bone area (25%), thickness (28.5%), and vBMD (11%). At the tibia, trabecular vBMD and number decrease by 26% and 17.5%, respectively. Tibia cortical bone area, thickness, and section modulus showed a >30% decrease, whereas vBMD reduction reached 13%. Geometry parameters at the tibia displayed the greatest differences between healthy and fractured patients and between wrist and hip fractures.
Bioactive Nanofibers Instruct Cells to Proliferate and Differentiate During Enamel Regeneration
Authors: Huang Zhan , Sargeant Timothy D , Hulvat James F , Mata Alvaro , Bringas Pablo , Koh Chung-Yan , Stupp Samuel I , Snead Malcolm L
Published: July 2008

During tooth development, ectoderm-derived ameloblast cells create enamel by synthesizing a complex protein mixture serving to control cell to matrix interactions and the habit of hydroxyapatite crystallites. Using an in vitro cell and organ culture system, we studied the effect of artificial bioactive nanostructures on ameloblasts with the long-term goal of developing cell-based strategies for tooth regeneration. We used branched peptide amphiphile molecules containing the peptide motif Arg-Gly-Asp, or “RGD” (abbreviated BRGD-PA), known to self-assemble in physiologic environments into nanofibers that display on their surfaces high densities of this biological signal. Ameloblast-like cells (line LS8) and primary enamel organ epithelial (EOE) cells were cultured within PA hydrogels, and the PA was injected into the enamel organ epithelia of mouse embryonic incisors. The expression of amelogenin, ameloblastin, integrin α5, and integrin α6 was detected by quantitative real-time PCR and immunodetection techniques. We performed cell proliferation assay using BrdU labeling and a biomineralization assay using Alizarin red S staining with quantitative Ca2+ measurements. In the cell culture model, ameloblast-like cells (LS8) and primary EOE cells responded to the BRGD-PA nanostructures with enhanced proliferation and greater amelogenin, ameloblastin, and integrin expression levels. At the site of injection of the BRGD-PA in the organ culture model, we observed EOE cell proliferation with differentiation into ameloblasts as evidenced by their expression of enamel specific proteins. Ultrastructural analysis showed the nanofibers within the forming extracellular matrix, in contact with the EOE cells engaged in enamel formation and regeneration. This study shows that BRGD-PA nanofibers present with enamel proteins participate in integrin-mediated cell binding to the matrix with delivery of instructive signals for enamel formation.
Hormone Therapy Improves Femur Geometry Among Ethnically Diverse Postmenopausal Participants in the Women's Health Initiative Hormone Intervention Trials
Authors: Chen Zhao , Beck Thomas J , Cauley Jane A , Lewis Cora E , LaCroix Andrea , Bassford Tamsen , Wu Guanglin , Sherrill Duane , Going Scott
Published: July 2008

Loss of bone strength underlies osteoporotic fragility fractures. We hypothesized that hormone interventions significantly improve the structural geometry of proximal femur cross-sections. Study participants were from the Women's Health Initiative hormone intervention trials: either the conjugated equine estrogen (CEE) only (Nplacebo = 447, NCEE = 422) trial or the estrogen (E) plus progestin (P) (Nplacebo = 441, NE+P = 503) trial, who were 50–79 yr old at baseline and were followed up to 6 yr. BMD scans by DXA were conducted at baseline, year 1, year 3, and year 6. Femur geometry was derived from hip DXA scans using the hip structural analysis (HSA) method. Mixed effects models with the intent-to-treat analysis approach were used. There were no significant differences in treatment effects between the E-alone and the E + P trial, so the analyses were conducted with participants combined from both trials. Treatment benefits (p < 0.05) on femur geometry were observed as early as 1 yr after the intervention. From baseline to year 6, section modulus (a measure of maximum bending stress) was preserved, and buckling ratio (an index of cortical instability under compression) was reduced by hormone interventions (p < 0.05); the differences in the percent changes from baseline to year 6 between women on hormone intervention versus women on placebo were 2.3–3.6% for section modulus and –5.3% to – 4.3% for buckling ratio. Hormone interventions led to favorable changes in femur geometry, which may help explain the reduced fracture risk observed in hormone interventions.
Site-Specific Deterioration of Trabecular Bone Architecture in Men and Women With Advancing Age
Authors: Lochmüller Eva-Maria , Matsuura Maiko , Bauer Jan , Hitzl Wolfgang , Link Thomas M , Müller Ralph , Eckstein Felix
Published: July 2008

We tested the hypothesis that the age dependence of trabecular bone microstructure differs between men and women and is specific to skeletal site. Furthermore, we aimed to investigate the microstructural pattern of bone loss in aging. Microstructural properties of trabecular bone were measured in vitro in 75 men and 75 age-matched women (age, 52–99 yr) using μCT. Trabecular bone samples were scanned at a 26-μm isotropic resolution at seven anatomical sites (i.e., distal radius, T10 and L2 vertebrae, iliac crest, femoral neck and trochanter, and calcaneus). DXA measurements were obtained at the distal radius and proximal femur and QCT was used at T12. No significant decrease in bone density or structure with age was found in men using μCT, DXA, or QCT at any of the anatomical sites. In women, a significant age-dependent decrease in BV/TV was observed at most sites, which was strongest at the iliac crest and weakest at the distal radius. At most sites, the reduction in BV/TV was associated with an increase in structure model index, decrease in Tb.N, and an increase in Tb.Sp. Only in the calcaneus was it associated with a significant decrease in Tb.Th. In conclusion, a significant, site-specific correlation of trabecular bone microstructure with age was found in women but not in men of advanced age. The microstructural basis by which a loss of BV/TV occurs with age can vary between anatomical sites.
Efficacy of Bazedoxifene in Reducing New Vertebral Fracture Risk in Postmenopausal Women With Osteoporosis: Results From a 3-Year, Randomized, Placebo-, and Active-Controlled Clinical Trial
Authors: Silverman Stuart L , Christiansen Claus , Genant Harry K , Vukicevic Slobodan , Zanchetta José R , de Villiers Tobie J , Constantine Ginger D , Chines Arkadi A
Published: July 2008

In this 3-yr, randomized, double-blind, placebo- and active-controlled study, healthy postmenopausal women with osteoporosis (55–85 yr of age) were treated with bazedoxifene 20 or 40 mg/d, raloxifene 60 mg/d, or placebo. The primary endpoint was incidence of new vertebral fractures after 36 mo; secondary endpoints included nonvertebral fractures, BMD, and bone turnover markers. Among 6847 subjects in the intent-to-treat population, the incidence of new vertebral fractures was significantly lower (p < 0.05) with bazedoxifene 20 mg (2.3%), bazedoxifene 40 mg (2.5%), and raloxifene 60 mg (2.3%) compared with placebo (4.1%), with relative risk reductions of 42%, 37%, and 42%, respectively. The treatment effect was similar among subjects with or without prevalent vertebral fracture (p = 0.89 for treatment by baseline fracture status interaction). The incidence of nonvertebral fractures with bazedoxifene or raloxifene was not significantly different from placebo. In a posthoc analysis of a subgroup of women at higher fracture risk (femoral neck T-score ≤ –3.0 and/or ≥1 moderate or severe vertebral fracture or multiple mild vertebral fractures; n = 1772), bazedoxifene 20 mg showed a 50% and 44% reduction in nonvertebral fracture risk relative to placebo (p = 0.02) and raloxifene 60 mg (p = 0.05), respectively. Bazedoxifene significantly improved BMD and reduced bone marker levels (p < 0.001 versus placebo). The incidence of vasodilatation, leg cramps, and venous thromboembolic events was higher with bazedoxifene and raloxifene compared with placebo. In conclusion, bazedoxifene significantly reduced the risk of new vertebral fracture in postmenopausal women with osteoporosis and decreased the risk of nonvertebral fracture in subjects at higher fracture risk.
Effect of Temporal Changes in Bone Turnover on the Bone Mineralization Density Distribution: A Computer Simulation Study
Authors: Ruffoni Davide , Fratzl Peter , Roschger Paul , Phipps Roger , Klaushofer Klaus , Weinkamer Richard
Published: July 2008

The heterogeneous distribution of mineral content in trabecular bone reflects the continuous renewal of bone material in bone remodeling and the subsequent increase in mineral content in the newly formed bone packets. The bone mineralization density distribution (BMDD) is typically used to describe this nonuniform mineral content of the bone matrix. Our mathematical model describes changes of the BMDD of trabecular bone as a function of bone resorption and deposition rates and the mineralization kinetics in a newly formed bone packet. Input parameters used in the simulations were taken from experimental studies. The simulations of the time evolution of the BMDD after increase in bone turnover (perimenopausal period) resulted in a shift of the BMDD toward lower values of the mineral content. Transiently, there was a broadening of the BMDD configuration partly showing two peaks, which points to a strongly heterogeneous distribution of the mineral. Conversely, when the remodeling rate was reduced (antiresorptive therapy), the BMDD shifted toward higher values of the mineral content. There was a transient narrowing of the distribution before broadening again to reach the new steady state. Results from this latter simulation are in good agreement with measurements of the BMDD of patients after 3 and 5 yr of treatment with risedronate. Based on available experimental data on bone remodeling, this model gives reliable predictions of changes in BMDD, an important factor of bone material quality. With the availability of medications with a known effect on bone turnover, this knowledge opens the possibility for therapeutic manipulation of the BMDD.
Unraveling Ambiguous NAT2 Genotyping Data
Authors: Agúndez José A G , Golka Klaus , Martínez Carmen , Selinski Silvia , Blaszkewicz Meinolf , García-Martín Elena
Published: July 2008

Background: Arylamine N-acetyltransferase 2 (CoASAc; NAT2, EC 2.3.1.5) is a drug-metabolizing enzyme that displays common polymorphisms leading to impaired drug metabolism and adverse drug effects. Determination of the N-acetyltransferase 2 (arylamine N-acetyltransferase) (NAT2) genotype in clinical practice is hampered by the occurrence of ambiguous haplotype combinations that may lead to patient misclassification. We determined the frequencies for ambiguous NAT2 haplotypes and diplotypes in a white population and investigated the use of PHASE v2.1.1, a statistical program for haplotype reconstruction, to clarify this ambiguity and classify individuals according to their acetylation status.

Methods: By means of allele-specific haplotype mapping and sequencing, we determined the haplotypes for 7 common single-nucleotide polymorphisms in the NAT2 gene (n = 2624 haplotypes). To test the performance of PHASE, actual genotypes were deconstructed and then reconstructed by haplotype prediction.

Results: We identified 21 NAT2 allelic variants, including a new variant allele that combines the single-nucleotide polymorphisms rs1801279, rs1799929, and rs1208. In contrast, the previously described variant alleles *5G, *5J, *6E, *7A, *11A, *11B, and *14B were not identified in the study population. Ambiguous haplotypes were observed in 98 alleles (3.7%), and ambiguous diplotypes were observed in 64 individuals (4.9%). Eleven individuals (0.8%) were misclassified by the use of haplotype prediction.

Conclusions: Ambiguous NAT2 genotyping data are common. Actual NAT2 genotypes cannot be fully determined by haplotype prediction techniques. This study provides real haplotype data that can be used as a guide to convert NAT2 haplotypes and diplotypes into actual genotypes in white individuals.
Propagation of bovine spermatogonial stem cells in vitro
Authors: Aponte Pedro M , Soda Takeshi , Teerds Katja J , Mizrak S Canan , van de Kant Henk J G , de Rooij Dirk G
Published: July 2008

The access to sufficient numbers of spermatogonial stem cells (SSCs) is a prerequisite for the study of their regulation and further biomanipulation. A specialized medium and several growth factors were tested to study the in vitro behavior of bovine type A spermatogonia, a cell population that includes the SSCs and can be specifically stained for the lectin Dolichos biflorus agglutinin. During short-term culture (2 weeks), colonies appeared, the morphology of which varied with the specific growth factor(s) added. Whenever the stem cell medium was used, round structures reminiscent of sectioned seminiferous tubules appeared in the core of the colonies. Remarkably, these round structures always contained type A spermatogonia. When leukemia inhibitory factor (LIF), epidermal growth factor (EGF), or fibroblast growth factor 2 (FGF2) were added, specific effects on the numbers and arrangement of somatic cells were observed. However, the number of type A spermatogonia was significantly higher in cultures to which glial cell line-derived neurotrophic factor (GDNF) was added and highest when GDNF, LIF, EGF, and FGF2 were all present. The latter suggests that a proper stimulation of the somatic cells is necessary for optimal stimulation of the germ cells in culture. Somatic cells present in the colonies included Sertoli cells, peritubular myoid cells, and a few Leydig cells. A transplantation experiment, using nude mice, showed the presence of SSCs among the cultured cells and in addition strongly suggested a more than 10 000-fold increase in the number of SSCs after 30 days of culture. These results demonstrate that bovine SSC self-renew in our specialized bovine culture system and that this system can be used for the propagation of these cells.
Excess estrogen sulfoconjugation as the possible cause for a poor sign of parturition in pregnant cows carrying somatic cell clone fetuses
Authors: Hirayama Hiroki , Sawai Ken , Moriyasu Satoru , Hirayama Muneyuki , Goto Yuji , Kaneko Etsushi , Miyamoto Akio , Ushizawa Koichi , Takahashi Toru , Minamihashi Akira
Published: July 2008

We conducted this study to elucidate a factor causing a poor sign of parturition and prolonged gestation, which is frequently observed in cows carrying somatic clone fetuses. Pre-partum rises in concentrations of plasma estrone and estradiol-17β in the recipient cows pregnant with clones were subtle. By contrast, the plasma concentration of estrone sulfate in clone pregnancies increased gradually from pre-initiation of parturition induction whereas control cows that received in vivo-derived embryos showed a significant increase at parturition. Therefore, in clone pregnancies, the ratio of estrone/estrone sulfate was low during the pre-partum period compared with control. Messenger RNA expression of estrogen sulfotransferase (SULT1E1) in the placenta at parturition was significantly higher in clone pregnancies than control pregnancies and was localized in binucleate cells (BNC). SULT1E1 mRNA abundance was negatively and positively correlated with concentrations of maternal estrone and estrone sulfate at parturition respectively. Messenger RNA expressions of estrogen sulfatase (STS) and aromatase (CYP19) were similar between clone and control pregnancies and were localized in BNC and caruncular epithelial cells. STS and CYP19 mRNA abundances showed positive correlations with maternal estradiol-17β concentration. The population of BNC in the placenta did not differ between clone and control pregnancies. Plasma cortisol concentration of vaginally delivered newborn clone calves was comparable with those of control, although cesarean section delivered clone calves showed a low concentration. These results suggest that excess estrogen sulfoconjugation is the reason for the perturbed low ratio of active to inactive estrogens and the resulting hormonal imbalance contributes to the lack of overt signs of readiness for parturition in cows pregnant with clones.
Disruption of the endothelial nitric oxide synthase gene affects ovulation, fertilization and early embryo survival in a knockout mouse model
Authors: Pallares Pilar , Garcia-Fernandez Rosa A , Criado Luis M , Letelier Claudia A , Esteban David , Fernandez-Toro Jose M , Flores Juana M , Gonzalez-Bulnes Antonio
Published: July 2008

Two consecutive experiments determined whether disruption of the endothelial nitric oxide synthases (NOS) gene (Nos3) affects ovulation, fertilization, implantation, and embryo development. In the first trial, Nos3-knockout mice (groups Nos3−/−) and wild-type mice (groups Nos3+/+) showed significant differences in mean number of corpora lutea (9.7±1.2 in Nos3−/− versus 14.2±1.2 in Nos3+/+; P<0.01), rate of anovulation (48.3±7.3% in Nos3−/− versus 29.7±6.3 in Nos3+/+; P<0.05), total mean number of recovered oocytes/zygotes (4.0±1.1 in Nos3−/− versus 10.4±1.6 in Nos3+/+; P<0.01), and non-fertilization rate (50.7 in Nos3−/− versus 3.3% in Nos3+/+; P<0.001). In the second trial, implantation and early pregnancy losses in Nos3-knockout and wild-type dams were detected by real-time ultrasound imaging. The number of embryos reaching implantation was higher in Nos3+/+ than in Nos3−/− mice (7.5±0.4 vs 4.0±0.4; P<0.005); thereafter, embryo losses were detected between days 8.5 and 13.5, in 62.5% of the Nos3-knockout dams and, at days 10.5 and 11.5, in 16.7% of the control females (P<0.005). Thus, NO and NOS3 deficiencies affect reproductive and developmental features in the Nos3-knockout mouse model.
Frequency-Dependent Selection and the Evolution of Assortative Mating
Authors: Otto Sarah P , Servedio Maria R , Nuismer Scott L
Published: July 2008

A long-standing goal in evolutionary biology is to identify the conditions that promote the evolution of reproductive isolation and speciation. The factors promoting sympatric speciation have been of particular interest, both because it is notoriously difficult to prove empirically and because theoretical models have generated conflicting results, depending on the assumptions made. Here, we analyze the conditions under which selection favors the evolution of assortative mating, thereby reducing gene flow between sympatric groups, using a general model of selection, which allows fitness to be frequency dependent. Our analytical results are based on a two-locus diploid model, with one locus altering the trait under selection and the other locus controlling the strength of assortment (a “one-allele” model). Examining both equilibrium and nonequilibrium scenarios, we demonstrate that whenever heterozygotes are less fit, on average, than homozygotes at the trait locus, indirect selection for assortative mating is generated. While costs of assortative mating hinder the evolution of reproductive isolation, they do not prevent it unless they are sufficiently great. Assortative mating that arises because individuals mate within groups (formed in time or space) is most conducive to the evolution of complete assortative mating from random mating. Assortative mating based on female preferences is more restrictive, because the resulting sexual selection can lead to loss of the trait polymorphism and cause the relative fitness of heterozygotes to rise above homozygotes, eliminating the force favoring assortment. When assortative mating is already prevalent, however, sexual selection can itself cause low heterozygous fitness, promoting the evolution of complete reproductive isolation (akin to “reinforcement”) regardless of the form of natural selection.
Dissection of Darkener of Apricot Kinase Isoform Functions in Drosophila
Authors: Kpebe Arlette , Rabinow Leonard
Published: July 2008

The Darkener of apricot (Doa) locus of Drosophila encodes a LAMMER protein kinase affecting alterative splicing, and hence sex determination, via the phosphorylation of SR and SR-like proteins. Doa encodes 6 different kinases via alternative promoter usage. To provide further insight into the roles of the multiple isoforms, we mapped polymorphisms, deletions, and P-element insertions in the locus, identifying several that are largely, if not completely, isoform specific in their effects. These tests, along with the use of lines permitting overexpression and interfering RNA expression, demonstrate that the major isoforms of 55 and 105 kDa perform separate functions. The 105-kDa and a minor 138-kDa isoform are both vital but do not apparently perform functions essential for sex determination. Curiously, male-specific lethality induced by overexpression of the 55-kDa kinase in the larval fat body is rescued by coexpression of TRA, suggesting a sex-specific physiological role for this isoform. Maternal effects in which the survival of heteroallelic adults depends upon the direction of the cross are consistent with a role for a 105-kDa cytoplasmic kinase in oogenesis or early larval development.
Within-Generation Mutation Variance for Litter Size in Inbred Mice
Authors: Casellas Joaquim , Medrano Juan F
Published: July 2008

The mutational input of genetic variance per generation ($\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{{\sigma}}_{\mathrm{m}}^{2}\) \end{document}$) is the lower limit of the genetic variability in inbred strains of mice, although greater values could be expected due to the accumulation of new mutations in successive generations. A mixed-model analysis using Bayesian methods was applied to estimate $\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{{\sigma}}_{\mathrm{m}}^{2}\) \end{document}$ and the across-generation accumulated genetic variability on litter size in 46 generations of a C57BL/6J inbred strain. This allowed for a separate inference on $\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{{\sigma}}_{\mathrm{m}}^{2}\) \end{document}$ and on the additive genetic variance in the base population ($\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{{\sigma}}_{\mathrm{a}}^{2}\) \end{document}$). The additive genetic variance in the base generation was 0.151 and quickly decreased to almost null estimates in generation 10. On the other hand, $\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{{\sigma}}_{\mathrm{m}}^{2}\) \end{document}$ was moderate (0.035) and the within-generation mutational variance increased up to generation 14, then oscillating between 0.102 and 0.234 in remaining generations. This pattern suggested the existence of a continuous uploading of genetic variability for litter size ($\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(h^{2}{=}0.045\) \end{document}$). Relevant genetic drift was not detected in this population. In conclusion, our approach allowed for separate estimation of $\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{{\sigma}}_{\mathrm{a}}^{2}\) \end{document}$ and $\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{{\sigma}}_{\mathrm{m}}^{2}\) \end{document}$ within the mixed-model framework, and the heritability obtained highlighted the significant and continuous influence of new genetic variability affecting the genetic stability of inbred strains.
A Theory of Age-Dependent Mutation and Senescence
Authors: Moorad Jacob A , Promislow Daniel E L
Published: July 2008

Laboratory experiments show us that the deleterious character of accumulated novel age-specific mutations is reduced and made less variable with increased age. While theories of aging predict that the frequency of deleterious mutations at mutation–selection equilibrium will increase with the mutation's age of effect, they do not account for these age-related changes in the distribution of de novo mutational effects. Furthermore, no model predicts why this dependence of mutational effects upon age exists. Because the nature of mutational distributions plays a critical role in shaping patterns of senescence, we need to develop aging theory that explains and incorporates these effects. Here we propose a model that explains the age dependency of mutational effects by extending Fisher's geometrical model of adaptation to include a temporal dimension. Using a combination of simple analytical arguments and simulations, we show that our model predicts age-specific mutational distributions that are consistent with observations from mutation-accumulation experiments. Simulations show us that these age-specific mutational effects may generate patterns of senescence at mutation–selection equilibrium that are consistent with observed demographic patterns that are otherwise difficult to explain.
Functional Conservation of β-Hairpin DNA Binding Domains in the Mcm Protein of Methanobacterium thermoautotrophicum and the Mcm5 protein of Saccharomyces cerevisiae
Authors: Leon Ronald P , Tecklenburg Marianne , Sclafani Robert A
Published: July 2008

Mcm proteins are an important family of evolutionarily conserved helicases required for DNA replication in eukaryotes. The eukaryotic Mcm complex consists of six paralogs that form a heterohexameric ring. Because the intact Mcm2-7 hexamer is inactive in vitro, it has been difficult to determine the precise function of the different subunits. The solved atomic structure of an archaeal minichromosome maintenance (MCM) homolog provides insight into the function of eukaryotic Mcm proteins. The N-terminal positively charged central channel in the archaeal molecule consists of β-hairpin domains essential for DNA binding in vitro. Eukaryotic Mcm proteins also have β-hairpin domains, but their function is unknown. With the archaeal atomic structure as a guide, yeast molecular genetics was used to query the function of the β-hairpin domains in vivo. A yeast mcm5 mutant with β-hairpin mutations displays defects in the G1/S transition of the cell cycle, the initiation phase of DNA replication, and in the binding of the entire Mcm2-7 complex to replication origins. A similar mcm4 mutation is synthetically lethal with the mcm5 mutation. Therefore, in addition to its known regulatory role, Mcm5 protein has a positive role in origin binding, which requires coordination by all six Mcm2-7 subunits in the hexamer.
Differential Gene Expression of TRPM1, the Potential Cause of Congenital Stationary Night Blindness and Coat Spotting Patterns (LP) in the Appaloosa Horse (Equus caballus)
Authors: Bellone Rebecca R , Brooks Samantha A , Sandmeyer Lynne , Murphy Barbara A , Forsyth George , Archer Sheila , Bailey Ernest , Grahn Bruce
Published: July 2008

The appaloosa coat spotting pattern in horses is caused by a single incomplete dominant gene (LP). Homozygosity for LP (LP/LP) is directly associated with congenital stationary night blindness (CSNB) in Appaloosa horses. LP maps to a 6-cM region on ECA1. We investigated the relative expression of two functional candidate genes located in this LP candidate region (TRPM1 and OCA2), as well as three other linked loci (TJP1, MTMR10, and OTUD7A) by quantitative real-time RT–PCR. No large differences were found for expression levels of TJP1, MTMR10, OTUD7A, and OCA2. However, TRPM1 (Transient Receptor Potential Cation Channel, Subfamily M, Member 1) expression in the retina of homozygous appaloosa horses was 0.05% the level found in non-appaloosa horses (R = 0.0005). This constitutes a >1800-fold change (FC) decrease in TRPM1 gene expression in the retina (FC = −1870.637, P = 0.001) of CSNB-affected (LP/LP) horses. TRPM1 was also downregulated in LP/LP pigmented skin (R = 0.005, FC = −193.963, P = 0.001) and in LP/LP unpigmented skin (R = 0.003, FC = −288.686, P = 0.001) and was downregulated to a lesser extent in LP/lp unpigmented skin (R = 0.027, FC = −36.583, P = 0.001). TRP proteins are thought to have a role in controlling intracellular Ca2+ concentration. Decreased expression of TRPM1 in the eye and the skin may alter bipolar cell signaling as well as melanocyte function, thus causing both CSNB and LP in horses.
Use of Complementary and Alternative Medicine by Pediatric Patients With Functional and Organic Gastrointestinal Diseases: Results From a Multicenter Survey
Authors: Vlieger Arine M. , Blink Marjolein , Tromp Ellen , Benninga Marc A.
Published: July 2008

OBJECTIVES. Many pediatric patients use complementary and alternative medicine, especially when facing a chronic illness for which treatment options are limited. So far, research on the use of complementary and alternative medicine in patients with functional gastrointestinal disease has been scarce. This study was designed to assess complementary and alternative medicine use in children with different gastrointestinal diseases, including functional disorders, to determine which factors predicted complementary and alternative medicine use and to assess the willingness of parents to participate in future studies on complementary and alternative medicine efficacy and safety.

PATIENTS AND METHODS. The prevalence of complementary and alternative medicine use was assessed by using a questionnaire for 749 children visiting pediatric gastroenterology clinics of 9 hospitals in the Netherlands. The questionnaire consisted of 35 questions on the child's gastrointestinal disease, medication use, health status, past and future complementary and alternative medicine use, reasons for its use, and the necessity of complementary and alternative medicine research.

RESULTS. In this study population, the frequency of complementary and alternative medicine use was 37.6%. A total of 60.3% of this group had used complementary and alternative medicine specifically for their gastrointestinal disease. This specific complementary and alternative medicine use was higher in patients with functional disorders than organic disorders (25.3% vs 17.2%). Adverse effects of allopathic medication, school absenteeism, age ≤11 years, and a low effect of conventional treatment were predictors of specific complementary and alternative medicine use. Almost all (93%) of the parents considered it important that pediatricians initiate complementary and alternative medicine research, and 51% of parents were willing to participate in future complementary and alternative medicine trials.

CONCLUSIONS. Almost 40% of parents of pediatric gastroenterology patients are turning to complementary and alternative medicine for their child. Lack of effectiveness of conventional therapy, school absenteeism, and adverse effects of allopathic medication are more important predictors of complementary and alternative medicine use than the type of gastrointestinal disease. Because evidence on most complementary and alternative medicine modalities in children with gastrointestinal disorders is lacking, there is an urgent need for research in this field.
Hydroxyestrogens inhibit angiogenesis in swine ovarian follicles
Authors: Basini G , Bussolati S , Santini S E , Bianchi F , Careri M , Mangia A , Musci M , Grasselli F
Published: July 2008

The rapid, controlled, and cyclical nature of angiogenesis in the ovarian follicle suggests the potential for sex steroids to influence neovascularization. Angiogenesis is regulated by a local balance between the levels of endogenous stimulators and inhibitors. Multiple lines of evidence suggest that estrogens stimulate angiogenesis via effects on endothelial cells. However, it is of outstanding value to investigate the negative control of this process. Since the main estrogen metabolites, 2-hydroxyestradiol and 4-hydroxyestradiol (4-OHE2) have been demonstrated to function as anti-estrogen in several estrogen-dependent organs; the aim of this study was to investigate their potential involvement in the modulation of follicular angiogenesis. Hydroxyestrogens were quantified in swine follicular fluid and their effects were studied on granulosa cell vascular endothelial growth factor (VEGFA) production and tested in an angiogenesis bioassay. Our study documents that these molecules are physiologically present in swine follicular fluid and their concentrations significantly (P<0.001) increase during follicle development. Moreover, angiogenesis bioassay revealed that both hydroxyestrogens significantly (P<0.001) inhibited new vessel growth. We evidenced that the most potent negative effect is mediated by 4-OHE2. The anti-angiogenic potential of this molecule is also supported by its ability to inhibit (P<0.001) VEGFA production by granulosa cells. Increased knowledge in this area is of utmost importance for future therapeutic options to contrast infertility disorders associated with aberrant angiogenesis; this would be also very useful for the treatment of diseases characterized by disregulated angiogenesis and vascular regression.
Internal stability of crushed sands: experimental study
Authors: Valdes J. R. , Koprulu E.
Published: July 2008

The current paper documents an experimental study conducted to evaluate the internal stability of sands subjected to seepage at high stresses. A custom-made one-dimensional compression cell with fluid flow capabilities was used to load and flush saturated specimens composed of selected sands with heterogeneous mineral composition. The degree of internal stability (i.e. the extent to which a soil can retain its mobile particles) was quantified with both the size distribution curves and the relative amounts of fragments collected in the effluent. Results indicate that: (a) uniform internally stable sands become internally unstable at high stresses, albeit temporarily; and (b) internal instability features are dependent on mineral composition and the extent of particle breakage. Particle-level force analyses suggest that the internal stability of crushed sands is dependent on the hydrodynamic conditions imposed.