bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Era in the Ethics of Human Embryonic Stem Cell Research
Authors: Lo Bernard , Zettler Patricia , Cedars Marcelle I. , Gates Elena , Kriegstein Arnold R. , Oberman Michelle , Reijo Pera Renee , Wagner Richard M. , Wuerth Mary T. , Wolf Leslie E. , Yamamoto Keith R. 
Published: September 2005

AbstractScientific progress in human embryonic stem cell (hESC) research and increased funding make it imperative to look ahead to the ethical issues generated by the expected use of hESCs for transplantation. Several issues should be addressed now, even though phase I clinical trials of hESC transplantation are still in the future. To minimize the risk of hESC transplantation, donors of materials used to derive hESC lines will need to be recontacted to update their medical history and screening. Because of privacy concerns, such recontact needs to be discussed and agreed to at the time of donation, before new hESC lines are derived. Informed consent for phase I clinical trials of hESC transplantation also raises ethical concerns. In previous phase I trials of highly innovative interventions, allegations that trial participants had not really understood the risk and benefits caused delays in subsequent trials. Thus, researchers should consider what information needs to be discussed during the consent process for hESC clinical trials and how to verify that participants have a realistic understanding of the study. Lack of attention to the special ethical concerns raised by clinical trials of hESC transplantation and their implications for the derivation of new hESC lines may undermine or delay progress toward stem cell therapies.
Social and reproductive factors affecting cortisol levels in wild female golden lion tamarins (Leontopithecus rosalia)
Authors: Bales Karen L. , French Jeffrey A. , Hostetler Caroline M. , Dietz James M. 
Published: September 2005

AbstractThe steroid hormone cortisol has been associated with different levels of “stress” as well as different reproductive conditions in many primates. In callitrichids, cortisol has more often been reflective of female reproductive status than of chronic stress. In this study, we addressed the hypothesis that wild golden lion tamarin (Leontopithecus rosalia) females, whose social structure is characterized by low aggression and high social support, would not show rank (“stress”)‐related differences in glucocorticoids but would show reproductive changes. We collected 710 fecal samples from 22 adult females in Poço das Antas Reserve, Brazil, and nearby reintroduction areas, and assayed them for cortisol. Differences in cortisol levels were found between different reproductive conditions. Females in the first trimester of pregnancy had lower cortisol levels than nonpregnant females, although we did not differentiate between basal and ovulating levels in nonpregnant females. Cortisol rose in the third trimester of pregnancy. Primiparous females had a higher rise in the third trimester than multiparous females. No differences in cortisol levels were found among dominant females, ovulatory subordinate females, or anovulatory subordinate females. These results are similar to those obtained in other studies of callitrichid females. The lack of differences in cortisol excretion between dominants and subordinates is likely due to the low levels of overt aggression and the high level of social support available to subordinate females. Am J Primatol 67:25–35, 2005. © 2005 Wiley‐Liss, Inc.
Behavioral strategies and hormonal profiles of dominant and subordinate common marmoset (Callithrix jacchus) females in wild monogamous groups
Authors: Sousa Maria Bernardete Cordeiro , Albuquerque Ana Claudia Sales da Rocha , Albuquerque Fabiola da Silva , Araujo Arrilton , Yamamoto Maria Emilia , Arruda Maria de Fatima 
Published: September 2005

AbstractNew insights into the mating systems of common marmosets suggest that they are mainly monogamous, although polygyny and polyandry occasionally occur. Long‐term monitoring of wild common marmosets has shown that some reports of polygynous groups (i.e., groups that contain more than one reproducing female) in fact indicate an unbalanced reproductive output associated with extragroup copulation. In this study we describe the behavioral and hormonal profiles of common marmoset (Callithrix jacchus) females living in three wild monogamous groups (Q, PBf, and T), varying from five to 11 individuals, at Nísia Floresta field station, RN, Brazil. The mating system of the groups was previously characterized in terms of affiliative, sexual, and mate‐guarding behaviors. Behavioral data were collected once a week, and fecal samples were collected at least twice a week for 10–16 months, depending on the group. A preferential allogrooming relationship was recorded between dominant males and females. Under field conditions the reproductive inhibition of subordinate females appears to be more behavioral than hormonal, since subordinate females of the three groups ovulated and two conceived during the study. In these cases, the subordinate and dominant females reproduced 1 month apart, and infanticide (one case confirmed and one suspected) appeared to be part of the reproductive strategy of dominant females. Following the infanticide, ovarian inhibition (group T) or emigration and return to the natal group (group PBf) were observed. In the third group (Q) the subordinate female showed hormonal profiles compatible with pregnancy, but no infants were seen. These findings reflect the different alternatives that wild subordinate common marmoset females use to reproduce. Am. J. Primatol. 67:37–50, 2005. © 2005 Wiley‐Liss, Inc.
Behavioral indicators of ovarian phase in white‐faced capuchins (Cebus capucinus)
Authors: Carnegie Sarah D. , Fedigan Linda M. , Ziegler Toni E. 
Published: September 2005

AbstractIn many primate species, conspicuous behavioral and/or morphological changes are indicators of the fertile phase of the female cycle. However, several primate species, such as the white‐faced capuchin, lack these cues. This is referred to as “concealed ovulation,” and is argued to be a reproductive strategy that confuses paternity and lowers the risk of infanticide. We studied 10 adult female white‐faced capuchins in Santa Rosa National Park, Costa Rica, from January to June 2002. We determined their ovarian cycling patterns by analyzing fecal ovarian hormones, and compared simultaneously collected behavioral data to determine which, if any, cues females use to signal their fertile phases. We found that four females cycled during the study period but ceased to cycle without becoming pregnant. We considered several explanations for the lack of conception during our study, including reproductive seasonality. We found that female C. capucinus showed only small increases in rates of affiliative/proceptive behaviors directed toward adult males during their periovulatory phases. The best indicator of cycle phase was a significant increase in male affiliative behaviors (e.g., following and grooming bouts) and sexual behaviors (e.g., copulations and courtship displays) directed toward females during the periovulatory phase compared to the nonovulatory phase. Our finding that females exhibit little proceptive behavior, but that copulations and male courtship are nonetheless concentrated in periovulatory phases suggests that even though females do not provide behavioral and morphological cues to ovulation, males are still able to detect it. Infanticide occurs with some frequency in these monkeys, and there is evidence for postconceptive mating as a female strategy to lower risk of infanticide via paternity confusion. However, despite this occurrence of nonconceptive mating and the absence of female cues to ovulation, truly concealed ovulation does not appear to be characteristic of this study population of white‐faced capuchins. Am. J. Primatol. 67:51–68, 2005. © 2005 Wiley‐Liss, Inc.
Female testosterone, dominance rank, and aggression in an Ethiopian population of hybrid baboons
Authors: Beehner Jacinta C. , Phillips‐Conroy Jane E. , Whitten Patricia L. 
Published: September 2005

AbstractStudies on the relationship between female testosterone (T) measures and behavior, particularly in free‐ranging primate populations, remain scant. In this study we used fecal steroid analysis to examine the effects of seasonal, reproductive, and social factors on female T in a group of free‐ranging hybrid baboons (Papio sp.) in the Awash National Park of Ethiopia. We collected behavioral and hormonal data from 25 adult females across an 11‐month period. Solid phase extraction and radioimmunoassay (RIA) techniques were used to quantify T in 776 fecal samples collected weekly from each female. The results indicate that 1) the females had elevated T during pregnancy and during the wet season relative to other periods, 2) female dominance rank was positively related to T measures, and 3) female T and aggression were positively related within subjects but not across subjects. Higher T concentrations during pregnancy are consistent with other published profiles of pregnancy in primates. In combination with data on foraging, wet season increases in T may indicate contest competition for females. The rank–T relationship may be mediated by supplants or aggression. Finally, we discuss the different interpretations of the hormone–behavior relationship based on within‐ and across‐subject analyses. Am. J. Primatol. 67:101–119, 2005. © 2005 Wiley‐Liss, Inc.
Effects of omeprazole or cola beverage on the pharmacokinetics of oral DA‐8159, a new erectogenic, in rats
Authors: Lee Joo H. , Bae Soo K. , Kwon Jong W. , Kim Won B. , Lee Myung G. 
Published: September 2005

AbstractThe changes in pharmacokinetics of DA‐8159 by omeprazole with respect to inhibition of CYP3A1/2 in rats were evaluated. After oral administration of DA‐8159 at dose of 30 mg/kg to rats pretreated with oral omeprazole at 30 mg/kg for 1 week, the total area under the plasma concentration–time curve from time zero to time infinity (AUC) of DA‐8159 was significantly greater (37.5% increase) than that in control rats. This could be due to inhibition of metabolism of DA‐8159 by inhibition of CYP3A1/2 by omeprazole. The AUCDA‐8164 (a metabolite of DA‐8159)/AUCDA‐8159 ratio was also smaller (32.4% decrease) with omeprazole. After oral administration of DA‐8159 at a dose of 30 mg/kg to rats without or with cola beverage, the pharmacokinetic parameters of DA‐8159 and DA‐8164 were not significantly different between two groups of rats. This suggested that cola beverage did not have any considerable effects on CYP3A1/2 in rats. Copyright © 2005 John Wiley & Sons, Ltd.
Liquid chromatographic separation and UV determination of certain antihypertensive agents
Authors: Bhushan R. , Gupta Deepak , Singh Shravan Kumar 
Published: September 2005

AbstractThree antihypertensive agents were extracted and isolated from commercial formulations. These were purified and characterized by melting point, λmax and IR. The percentage recovery by extraction process was in the range 81–91%. Active ingredients from binary formulations were separated by RP‐HPLC using methanol–water (50:50 v/v) and by TLC using CHCl3–CH3OH (6:1) as mobile phase. Detection was by UV at 210 nm in HPLC, and by iodine vapors in TLC. The solvent conditions from TLC were transferred to open column chromatographic separation. Quantitative determination was carried out using TLC and column chromatography supplemented with UV spectrophotometry. Recovery was in the range 82–93%. Two combination of drugs, viz. amlodipine + ramipril and amlodipine + enalapril, were separated by the three modes of liquid chromatography. The percentage recovery was in the range 80–92% by open column. Copyright © 2005 John Wiley & Sons, Ltd.
A rapid HPLC method with fluorometric detection for determination of plasma itraconazole and hydroxy‐itraconazole concentrations in cystic fibrosis children with allergic bronchopulmonary aspergillosis
Authors: Redmann Stefanie , Charles Bruce G. 
Published: September 2005

AbstractThe development and validation of a simple, rapid and selective high‐performance liquid chromatography (HPLC) method is described for the quantitation of itraconazole and hydroxy‐itraconazole in 100 µL of plasma from a paediatric population. The mobile phase of methanol (75% v/v) and water (25% v/v) was pumped at 1 mL/min through a C18 Symmetry™ (3.9 mm i.d. × 150 mm) cartridge. Using a protein‐precipitation method, 100 µL internal standard (IS) solution (R051012, 555 µg/L in acetonitrile) were added to 100 µL of plasma followed by 10 µL zinc sulphate solution (20% w/v). Itraconazole, hydroxy‐itraconazole and IS eluted at 4.7, 8.3 and 12.5 min, respectively and were detected ßuorometrically at 250 nm (excitation) and 380 nm (emission). Recoveries were 87.1–96.7%. Calibrations in drug‐free plasma were linear (r2 > 0.99) from 50 to 2000 µg/L, using 1/c2 (c = concentration) weighting. Intraday and interday imprecision (CV%) was 4.8–17.3 and 6.3–16.6% for itraconazole, and 4.6–17.9 and 7.02–18.4% for hydroxy‐itraconazole. Inaccuracy was −7.1 to −14.7% for itraconazole and −0.1 to −9.7% for hydroxy‐itraconazole. The clinical application of this method was demonstrated by measurement of itraconazole and hydroxy‐itraconazole in plasma samples drawn from paediatric cystic fibrosis patients, who were prescribed itraconazole for treatment of allergic bronchopulmonary aspergillosis. Copyright © 2005 John Wiley & Sons, Ltd.
Palladium(0)‐Catalyzed Cycloisomerization of Enallenes
Authors: Närhi Katja , Franzén Johan , Bäckvall Jan‐E. 
Published: September 2005

AbstractA novel palladium(0)‐catalyzed cycloisomerization of enallenes has been developed. This reaction, catalyzed by [Pd(dba)2] (dba=dibenzylideneacetone) in acetic acid, results in the formation of cyclopentene derivatives and [n.3.0]bicyclic systems (n=3, 4) in good to high yields. The carbon–carbon bond‐forming step is highly stereoselective to give cis‐fused bicyclic systems. The presence of acetic acid as solvent and dba as ligand for palladium(0) turned out to be essential for the reaction in order to provide good reactivity and regioselectivity.
Internalization of a Peptide into Multilamellar Vesicles Assisted by the Formation of an α‐Oxo Oxime Bond
Authors: Richard Antoine , Bourel‐Bonnet Line 
Published: September 2005

AbstractAs part of a drug‐delivery project, we designed and synthesised a novel hydroxylamine cholesterol‐based anchor to ensure the chemoselective ligation of recognition patterns onto multilamellar vesicles by oxime ligation. The entry of a glyoxylyl peptide into the vesicles was unexpectedly assisted by the formation of the α‐oxo oxime bond. We studied extensively the kinetic and thermodynamic aspects of this phenomenon. Briefly, for a glyoxylyl peptide, the speed and ability to enter the vesicle were dependent upon 1) the presence of a hydroxylamine anchor of the type CholE3ONH2, 2) the amount of peptide engaged in the ligation and 3) the flip‐flop motion permitted by the different formulations, in which the presence of cholesterol seems to play an important role.
Total Synthesis of (+)‐Batzelladine A and (−)‐Batzelladine D, and Identification of Their Target Protein
Authors: Shimokawa Jun , Ishiwata Takanori , Shirai Koji , Koshino Hiroyuki , Tanatani Aya , Nakata Tadashi , Hashimoto Yuichi , Nagasawa Kazuo 
Published: September 2005

AbstractAsymmetric total synthesis of batzelladine A (1) and batzelladine D (2) has been achieved. Our synthesis of batzelladines features 1) stereoselective construction of the cyclic guanidine system by means of successive 1,3‐dipolar cycloaddition reaction and subsequent cyclization, 2) direct esterification of the bicyclic carboxylic acid 35 with the guanidine alcohol 8 or 59 to construct the whole carbon skeleton of batzelladines, and 3) one‐step formation of the α,β‐unsaturated aldehyde 53 from the primary alcohol 47 with tetra‐n‐propylammoniumperruthenate (TPAP), providing an efficient route to the left‐hand bicyclic guanidine alcohol of batzelladine A (1). With the synthetic compounds 1 and 2 in hand, their target protein was examined by using immobilized CD4 and gp120 affinity gels. The results indicated that batzelladines A (1) and D (2) bind specifically to CD4.
Characterizing the three‐dimensional organization of telomeres
Authors: Vermolen B. J. , Garini Y. , Mai S. , Mougey V. , Fest T. , Chuang T. C.‐Y. , Chuang A. Y.‐C. , Wark L. , Young I. T. 
Published: September 2005

AbstractBackgroundQuantitative analysis can be used in combination with fluorescence microscopy. Although the human eye is able to obtain good qualitative results, when analyzing the spatial organization of telomeres in interphase nuclei, there is a need for quantitative results based on image analysis.MethodsWe developed a tool for analyzing three‐dimensional images of telomeres stained by fluorescence in situ hybridization in interphase nuclei with DNA counterstained with 4′,6‐diamidino‐2‐phenylindole. After deconvolution of the image, we segmented individual telomeres. From the location of the telomeres we derived a distribution parameter ρT, which indicated whether the telomeres were in a disk (ρT ≫ 1) or not (ρT ≈ 1). We sorted mouse lymphocyte nuclei and measured ρT. We also performed a bromodeoxyuridine synchronous cell sorting experiment on live cells and measured ρT at several instances.ResultsMeasuring ρT for nuclei in G0/G1, S, and G2 produced 1.4 ± 0.1, 1.5 ± 0.2, and 14 ± 2, respectively, showing a significant difference between G2 and G0/G1 or S. For the bromodeoxyuridine synchronous cell sorting experiment, we found a cell cycle dependency of ρT and a correlation between ρT and an observer.ConclusionsIn this study we present a quantitative method to characterize the organization of telomeres using three‐dimensional imaging, image processing, and image analysis. © 2005 International Society for Analytical Cytology
Novel calibration method for flow cytometric fluorescence resonance energy transfer measurements between visible fluorescent proteins
Authors: Nagy Peter , Bene László , Hyun William C. , Vereb György , Braun Manuela , Antz Christof , Paysan Jacques , Damjanovich Sándor , Park John W. , Szöllsi János 
Published: September 2005

AbstractBackgroundThe combination of fluorescence resonance energy transfer (FRET) and flow cytometry offers a statistically firm approach to study protein associations. Fusing green fluorescent protein (GFP) to a studied protein usually does not disturb the normal function of a protein, but quantitation of FRET efficiency calculated between GFP derivatives poses a problem in flow cytometry.MethodsWe generated chimeras in which cyan fluorescent protein (CFP) was separated by amino acid linkers of different sizes from yellow fluorescent protein (YFP) and used them to calibrate the cell‐by‐cell flow cytometric FRET measurements carried out on two different dual‐laser flow cytometers. Then, CFP‐Kip1 was coexpressed in yeast cells with YFP and cyclin‐dependent kinase‐2 (Cdk2) and served as a positive control for FRET measurements, and CFP‐Kip1 coexpressed with a random peptide fused to YFP was the negative control.ResultsWe measured donor, direct, and sensitized acceptor fluorescence intensities and developed a novel way to calculate a factor (α) that characterized the fluorescence intensity of acceptor molecules relative to the same number of excited donor molecules, which is essential for quantifying FRET efficiency. This was achieved by calculating FRET efficiency in two different ways and minimizing the squared difference between the two results by changing α. Our method reliably detected the association of Cdk2 with its inhibitor, Kip1, whereas the nonspecific FRET efficiency between Cdk2 and a random peptide was negligible. We identified and sorted subpopulations of yeast cells showing interaction between the studied proteins.ConclusionsWe have described a straightforward novel calibration method to accurately quantitate FRET efficiency between GFP derivatives in flow cytometry. © 2005 International Society for Analytical Cytology
Fluorescence lifetime imaging in an optically sectioning programmable array microscope (PAM)
Authors: Hanley Quentin S. , Lidke Keith A. , Heintzmann Rainer , Arndt‐Jovin Donna J. , Jovin Thomas M. 
Published: September 2005

AbstractBackgroundThe programmable array microscopes (PAMs) are a family of instruments incorporating arbitrary control of the patterns of illumination and/or detection. The PAM can be used in sectioning and nonsectioning modes, thereby constituting a useful platform for fluorescence lifetime imaging.Methods and ResultsWe used a PAM for acquisition of optically sectioned and widefield fluorescence lifetime images, in which contrast was increased predominantly by suppressing out‐of‐focus light contributions. We simulate, display, and discuss the effects of blurring and fluorophore heterogeneity on lifetime imaging in widefield and confocal configurations.ConclusionSectioning improves the quality of lifetime images of samples with multiple fluorophores or spatially varying Förster resonance energy transfer. © 2005 International Society for Analytical Cytology.
Biphasic calcium response of platelet‐derived growth factor stimulated glioblastoma cells is a function of cell confluence
Authors: Vereb György , Feuerstein Burt G. , Hyun William C. , Fulwyler Mack J. , Balázs Margit , Szöllősi János 
Published: September 2005

AbstractBackgroundPrevious reports have linked the spiking or two‐phased character of calcium transients evoked by platelet‐derived growth factor (PDGF) to the position of cells in the cell cycle without regard to cell–cell contact and communication. Because cell confluence can regulate growth factor receptor expression and dephosphorylation, we investigated the effect of cell culture confluence and cell cycle on calcium responses of PDGF‐BB–stimulated A172 glioblastoma cells.MethodsDigital imaging cytometry was used to correlate the peak and duration of calcium response with bromodeoxyuridine positivity and DNA content and with culture confluence on a cell‐by‐cell basis.ResultsIn serum‐starved cultures, complete two‐phase calcium signals and shorter, lower spikes occurred independent of cell cycle phase. However, the confluence of cell culture seemed essential for inducing a complete response because cells in sparse cultures exhibited mostly short spikes with lower peaks or no transients at all.ConclusionBecause cell confluence, by virtue of cell–cell contacts, is assumed to be an important regulator of proliferation, one is tempted to speculate that in transformed cells the ability to produce stronger growth signals upon reaching confluence and facing contact inhibition could provide a proliferative advantage. © 2005 International Society for Analytical Cytology