bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid, high throughput determination of cervical cytology specimen adequacy using a capillary‐based cytometer
Authors: Polina Ryan , Sturgis Charles , Patterson John , Patterson Bruce K. 
Published: November 2007

AbstractDespite the fact that compact instruments dedicated to counting cells are readily available especially in hematology, liquid‐based cervical cytology specimen adequacy is still determined by pathologist review following the preparation of slides. More than 100 liquid‐based cervical cytology specimens collected in ThinPrep vials were processed into slides for diagnosis and assessment of specimen adequacy using the Bethesda 2001 criteria. Residual liquid (100 μL) was transferred to a single well of a 96‐well plate and run in a capillary cytometer (Guava Technologies, Hayward, CA) with forward scatter and side scatter detectors. We determined that the sensitivity and specificity of this assay for unsatisfactory samples was 100% and 97%, respectively, compared with cytopathologic examination. The difference in the concentration of ectocervical cells/μL (EPU) between samples determined to be unsatisfactory by virtue of less than an estimated 5,000 cells per slide and satisfactory samples were statistically significant (P< 0.001). Here, we report the use of this rapid specimen adequacy assay on a small, capillary based, personal cytometer. Use of this instrument reduced the amount of sample required by >90% and reduced the average per sample assay time from 120 s to 10 s compared with flow cytometry. © 2007 Clinical Cytometry Society
Cooperative activity of multiple upper layer proteins for thalamocortical axon growth
Authors: Maruyama Takuro , Matsuura Masahiro , Suzuki Kazuhiro , Yamamoto Nobuhiko 
Published: November 2007

AbstractDuring development, sensory thalamocortical (TC) axons grow into the neocortex and terminate primarily in layer 4. To study the molecular mechanism that underlies lamina‐specific TC axon termination, we investigated the responsiveness of TC axons to ephrin‐A5, semaphorin‐7A (Sema7A) and kit ligand (KL), which are expressed in the upper layers of the developing cortex. Dissociated cells of the dorsal thalamus from embryonic rat brain were cultured on dishes that were coated with preclustered Fc‐tagged extracellular domains of these molecules. Each protein was found to promote TC axon growth in a dose‐dependent fashion of a bell‐shaped curve. Any combination of the three proteins showed a cooperative effect in lower concentrations but not in higher concentrations, suggesting that their growth‐promoting activities act in a common pathway. The effect of spatial distributions of these proteins was further tested on a filter membrane, in which these proteins were printed at a size that recapitulates the scale of laminar thickness in vivo, using a novel protein‐printing technique, Simple‐To‐mAke Micropore Protein‐Printing (STAMP2) method. The results demonstrated that TC axons grew massively on the laminin‐coated region but were prevented from invading the adjacent ephrin‐A5‐printed region, suggesting that TC axons detect relative differences in the growth effect between these regions. Moreover, the inhibitory action of ephrin‐A5 was enhanced by copresence with KL and Sema7A. Together, these results suggest that the lamina‐specific TC axon targeting mechanism involves growth‐inhibitory activity by multiple molecules in the upper layers and detection in the molecular environments between the upper and deep layers. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008
Inter‐ and Intramolecular C–H···O Bonding in the Anions of 1,3‐Indandione Derivatives
Authors: Sigalov Mark , Krief Pnina , Shapiro Lev , Khodorkovsky Vladimir 
Published: November 2007

AbstractDerivatives of a series of 1,3‐indandione (1) self‐condensation products (2–4) and their anions (2a–4a) were investigated by NMR and UV/Vis spectroscopy and quantum mechanical calculations. These compounds exhibit a number of unusual features in their NMR spectra. Parent compound 1 is nearly not ionized in DMSO, whereas 3 is ionized completely. In contrast, derivatives 2 and 4 undergo partial ionization in DMSO and interaction between the neutral and anionic species affords the anionic intermolecular complexes, which exhibit both temperature‐ and concentration‐dependent NMR spectra. The NMR spectra of pure salts 2a and 3a are concentration independent, but temperature dependent. Charge delocalization in anions 2a and 3a gives rise to restricted rotation over the partial double bonds connecting the indane fragments. Energies of barriers to rotation were estimated from the temperature dependence of the 13C NMR spectra. The intramolecular aromatic C–H···O hydrogen bonding found previously in 2–4 is also observed in corresponding anions 2a–4a.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Cyclotetrapeptide Mimics Based on a 13‐Membered, Partially Modified Retro‐Inverso Structure
Authors: Gentilucci Luca , Cardillo Giuliana , Tolomelli Alessandra , Spampinato Santi , Sparta Antonino , Squassabia Federico 
Published: November 2007

AbstractCyclic tetrapeptides (CTP) incorporating a distinct β‐amino acid represent realistic conformationally homogeneous CTP analogs, and they can find application in medicinal chemistry as turn mimics and scaffolds. In this respect, we synthesized a small library of CTP‐mimics based on a 13‐membered, partially modified retro‐inverso (PMRI) structure containing a 1,2‐diamine as a β‐amino acid mimetic and malonic acid as a glycine surrogate. Conformational analysis revealed that the PMRI–CTP models containing an unsubstituted diamine (1, 2) exhibited a certain flexibility. On the contrary, the introduction of a chiral, substituted 1,2‐diamine rendered the backbone more rigid (3, 4) and induced type I β‐turn structures. The comparison with a β‐amino acid containing CTP revealed that the PMRI–CTPs can be regarded as alternative β‐turn scaffolds. To validate the structural deductions based on conformational analysis, we synthesized a couple of diastereomeric RGD analogs (5, 6) as integrin inhibitors, and we found a clear relationship between the 3D display of the pharmacophores and biological activity. In particular, 6 showed good efficacy in inhibiting fibronectin adhesion to the αvβ3 integrin‐expressing human melanoma cells SK‐MEL‐24 (EC50 = 3.7 × 10–7). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Identification of resident hepatic stem cell populations
Authors: Shackel Nicholas A , Warner Fiona J , Kowdley Kris , McCaughan Geoffrey , Trautwein Christian 
Published: November 2007

Abstract

Human hepatic stem cells (hHpSCs), which are pluripotent precursors of hepatoblasts and thence of hepatocytic and biliary epithelia, are located in ductal plates in fetal livers and in Canals of Hering in adult livers. They can be isolated by immunoselection for epithelial cell adhesion molecule-positive (EpCAM+) cells, and they constitute approximately 0.5–2.5% of liver parenchyma of all donor ages. The self-renewal capacity of hHpSCs is indicated by phenotypic stability after expansion for >150 population doublings in a serum-free, defined medium and with a doubling time of approximately 36 h. Survival and proliferation of hHpSCs require paracrine signaling by hepatic stellate cells and/or angioblasts that coisolate with them. The hHpSCs are approximately 9 microm in diameter, express cytokeratins 8, 18, and 19, CD133/1, telomerase, CD44H, claudin 3, and albumin (weakly). They are negative for alpha-fetoprotein (AFP), intercellular adhesion molecule (ICAM) 1, and for markers of adult liver cells (cytochrome P450s), hemopoietic cells (CD45), and mesenchymal cells (vascular endothelial growth factor receptor and desmin). If transferred to STO feeders, hHpSCs give rise to hepatoblasts, which are recognizable by cordlike colony morphology and up-regulation of AFP, P4503A7, and ICAM1. Transplantation of freshly isolated EpCAM+ cells or of hHpSCs expanded in culture into NOD/SCID mice results in mature liver tissue expressing human-specific proteins. The hHpSCs are candidates for liver cell therapies.

Reproduced from Journal of Experimental Medicine, 2007, 204:1973–1987. Copyright 2007 Rockefeller University Press.
Calcium‐ and pH‐dependent localization of annexin A6 isoforms in Balb/3T3 fibroblasts reflecting their potential participation in vesicular transport
Authors: Strzelecka‐Kiliszek Agnieszka , Buszewska Malgorzata E. , Podszywalow‐Bartnicka Paulina , Pikula Slawomir , Otulak Katarzyna , Buchet Rene , Bandorowicz‐Pikula Joanna 
Published: November 2007

AbstractAnnexin A6 (AnxA6), calcium‐ and membrane‐binding protein, is involved in membrane dynamics. It exists in the cell in two isoforms, AnxA6‐1 and AnxA6‐2, varying only by the VAAEIL sequence. In most cells, AnxA6‐1 predominates. A limited number of observations suggests that both isoforms differ from each other functionally. The EGF‐dependent Ca2+influx in A431 cells is inhibited only by AnxA6‐1. Moreover, AnxA6‐2 was found to exhibit higher affinity for Ca2+. In this report we addressed the potential significance of the VAAEIL deletion in AnxA6‐2. For this purpose, we expressed AnxA6 isoform cDNAs in bacteria or mouse Balb/3T3 fibroblasts. The recombinant AnxA6‐2 was characterized by a less extended molecular shape than that of AnxA6‐1 and required a narrower [Ca2+] range to bind liposomes. Upon lowering pH in the presence of EGTA recombinant AnxA6‐2 became less hydrophobic than AnxA6‐1 as revealed by the Triton X‐114 partition. Furthermore, AnxA6‐2 revealed stronger F‐actin binding than that of AnxA6‐1. Immunofluorescence microscopy showed that the EGFP‐tagged AnxA6 isoforms expressed in Balb/3T3 fibroblasts relocate in a Ca2+‐ and H+‐sensitive manner to the vesicular structures in a perinuclear region or in cytosol. Cell fractionation showed that in resting conditions AnxA6‐1 is associated with early endosomes and AnxA6‐2 with late endosomes, and an increase in [Ca2+] and/or [H+] induced their opposite distribution. These findings suggest a potentially independent regulation, localization, and function of AnxA6 isoforms in Balb/3T3 fibroblasts. More generally, our findings suggest distinct functions of AnxA6 isoforms in membrane dynamics. J. Cell. Biochem. 104: 418–434, 2008. © 2007 Wiley‐Liss, Inc.
The hardness kernel as the basis for global and local reactivity indices
Authors: Torrent‐Sucarrat Miquel , Salvador Pedro , Solà Miquel , Geerlings Paul 
Published: November 2007

AbstractIn a very recent article (Torrent‐Sucarrat et al., J Comput Chem 2007, 28, 574), we have shown how to evaluate the global hardness for polyatomic molecules using a hardness kernel approximation. We present here an extension of this previous work by improving the model used to evaluate the hardness kernel and the Fukui function. In addition, the concept of the local hardness is analyzed in detail, and for the first time, profiles of local hardness with kinetic and exchange‐correlation contributions for polyatomic molecules are reported. Finally, the concept of condensed atomic hardness is introduced and its usefulness as chemical reactivity descriptor is examined. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
Relaxation of the mouse pubic symphysis during late pregnancy is not accompanied by the influx of granulocytes
Authors: Rosa Renata Giardini , Tarsitano Christiane Aparecida Badin , Hyslop Stephen , Yamada Áureo Tatsumi , Toledo Olga Maria S. , Joazeiro Paulo Pinto 
Published: November 2007

AbstractIn some animals, such as mice and guinea pigs, a hormonally controlled mechanism increases the flexibility of the pubic symphysis and enhances the cervical remodeling necessary for safe delivery. Cervical ripening during pregnancy is associated with a paradoxical influx of leukocytes. However, the changes in cell metabolism during relaxation of the mouse pubic symphysis for delivery have not been extensively studied. In this work, we used light microscopy and transmission and scanning electron microcopy, as well as immunohistochemistry and Western blotting for MMP‐8, to investigate the involvement of granulocytes or resident stromal cells in the relaxation of the virgin pubic symphysis during late pregnancy (days 18 and 19, before delivery) in vivo and in explanted joints. MMP‐8 was studied because this collagenase is a hallmark for cervical ripening associated with the influx of granulocytes during late pregnancy. Extensive dissolution and disorganization of the extracellular matrix was seen around fibroblastic‐like cells in late pregnancy. In contrast to the cervix (positive control), morphological and immunohistochemical analyses revealed that there was no characteristic cellular inflammatory response in the interpubic tissue. Staining for MMP‐8 was observed in chondroid and fibroblastic‐like cells of virgin and relaxed interpubic ligament, respectively. However, no granulocytes were seen during the extensive remodeling of the pubic joint in late pregnancy. These results indicate that constitutive stromal cells may have an important role in tissue relaxation during remodeling of the pubic symphysis in pregnancy. Microsc. Res. Tech., 2008. © 2007 Wiley‐Liss, Inc.
Cortical evoked potentials from pallidal stimulation in patients with primary generalized dystonia
Authors: Tisch Stephen , Rothwell John C. , Zrinzo Ludvic , Bhatia Kailash P. , Hariz Marwan , Limousin Patricia 
Published: November 2007

AbstractDeep brain stimulation (DBS) of globus pallidus internus (GPi) has emerged as an effective treatment for primary generalized dystonia. However, the physiological mechanisms of improvement are not fully understood. Cortical activity in response to pallidal stimulation was recorded in 6 patients with primary generalized dystonia >6 months after bilateral GPi DBS. Scalp electroencephalogram was recorded using 60 surface electrodes during 10 Hz bipolar pallidal DBS at each electrode contact pair. Anatomical position of the electrode contacts in relation to the GPi, medial medullary lamina and globus pallidus externus (GPe) was determined from the postoperative stereotactic MRI. In all six patients an evoked potential (EP) was observed with average onset latency of 10.9 ms ± 0.77, peak latency 26.6 ms ± 1.6, distributed mainly over the ipsilateral hemisphere, maximal centrally. The mean amplitude of this potential was larger with stimulation in posteroventral GPi than in GPe (3.36 μV vs. 0.50 μV, P < 0.0001). The EP was absent in one patient‐side, ipsilateral to a previous thalamotomy. Low frequency GPi stimulation produces an EP distributed centrally over the ipsilateral hemisphere. The latency and distribution of the EP are consistent with stimulation of pallidothalamic neurons projecting to the sensorimotor cortex. Because the EP is larger and more consistently present with stimulation of posteroventral GPi than GPe, it may provide a physiological tool to identify contacts within the optimal surgical target. © 2007 Movement Disorder Society
Lung MRI using an MR‐compatible active breathing control (MR‐ABC)
Authors: Arnold Johannes F.T. , Mörchel Philipp , Glaser Eckard , Pracht Eberhard D. , Jakob Peter M. 
Published: November 2007

AbstractThis work introduces an MR‐compatible active breathing control device (MR‐ABC) that can be applied to lung imaging. An MR‐ABC consists of a pneumotachograph for respiratory monitoring and an airway‐sealing unit. Using an MR‐ABC, the subjects were forced to suspend breathing for short time intervals, which were used in turn for data acquisition. While the breathing flow was stopped, data acquisition was triggered by ECG to achieve simultaneous cardiac and respiratory synchronization and thus avoid artifacts from blood flow or heart movement. The flow stoppage allowed a prolonged acquisition window of up to 1.5 sec. To evaluate the potential of an MR‐ABC for segmented k‐space acquisition, diaphragm displacement was investigated in five volunteers and compared with images acquired using breath‐holding, a respiratory belt, and free breathing. Respiratory movement was comparatively low using the breath‐hold approach, a respiratory belt or an MR‐ABC. During free‐breathing diaphragm displacement was comparatively large. To demonstrate the potential of an MR‐ABC, lung MRI was performed using whole‐chest 3D gradient‐echo imaging, multislice turbo spin‐echo (TSE) imaging, and short tau inversion recovery TSE (STIR‐TSE). Cardiorespiratory synchronization was used for each sequence. None of the volunteers reported any discomfort or inconvenience when using an MR‐ABC. Flow stoppage of up to 2.5 sec per breathing cycle was well tolerated, therefore allowing for a reduction of the total imaging time as compared to usage of a respiratory belt or MR navigator. Magn Reson Med, 2007. © 2007 Wiley‐Liss, Inc.
Compartmental relaxation and diffusion tensor imaging measurements in vivo in λ‐carrageenan‐induced edema in rat skeletal muscle
Authors: Fan Reuben H. , Does Mark D. 
Published: November 2007

AbstractIntegrated diffusion tensor T2 measurements were made on normal and edematous rat muscle, and the data were fitted with one‐ and two‐compartment models, respectively. Edematous muscle exhibited a short‐lived component (T2 = 28 ± 6 ms), with diffusion characteristics similar to that of normal muscle, and a long‐lived component (T2 = 96 ± 27 ms), with greater mean apparent diffusion coefficient (ADC) and lower fractional anisotropy (FA). With this two‐component description of diffusion and relaxation, values of ADC and FA estimated with a conventional pulsed‐gradient spin‐echo sequence will depend on the echo time, relative fraction of short‐lived and long‐lived water signals, and the intrinsic ADC and FA values within the tissue. On the basis of the relative differences in water diffusion properties between long‐lived and short‐lived water signals, as well as the similarities between the short‐lived component and normal tissue, it is postulated that these two signal components largely reflect intracellular and extracellular water. Copyright © 2007 John Wiley & Sons, Ltd.
Solving the hub location problem in a star–star network
Authors: Labbé Martine , Yaman Hande 
Published: November 2007

AbstractWe consider the problem of locating hubs and assigning terminals to hubs for a telecommunication network. The hubs are directly connected to a central node and each terminal node is directly connected to a hub node. The aim is to minimize the cost of locating hubs, assigning terminals and routing the traffic between hubs and the central node. We present two formulations and show that the constraints are facet‐defining inequalities in both cases. We test the formulations on a set of instances. Finally, we present a heuristic based on Lagrangian relaxation. © 2007 Wiley Periodicals, Inc. NETWORKS, 2008
Polynomial algorithms for partitioning a tree into single‐center subtrees to minimize flat service costs
Authors: Apollonio N. , Lari I. , Ricca F. , Simeone B. , Puerto J. 
Published: November 2007

AbstractThis paper deals with the following graph partitioning problem. Consider a connected graph with n nodes, p of which are centers, while the remaining ones are units. For each unit‐center pair there is a fixed service cost and the goal is to find a partition into connected components such that each component contains only one center and the total service cost is minimum. This problem is known to be NP‐hard on general graphs, and here we show that it remains such even if the service cost is monotone and the graph is bipartite. However, in this paper we derive some polynomial time algorithms for trees. For this class of graphs we provide several reformulations of the problem as integer linear programs proving the integrality of the corresponding polyhedra. As a consequence, the tree partitioning problem can be solved in polynomial time either by linear programming or by suitable convex nondifferentiable optimization algorithms. Moreover, we develop a dynamic programming algorithm, whose recursion is based on sequences of minimum weight closure problems, which solves the problem on trees in O(np) time. © 2007 Wiley Periodicals, Inc. NETWORKS, 2008
Prostate‐specific antigen levels in relation to cadmium exposure and zinc intake: results from the 2001–2002 national health and nutrition examination survey
Authors: van Wijngaarden Edwin , Singer Eric A. , Palapattu Ganesh S. 
Published: November 2007

AbstractBACKGROUNDCadmium exposure has been suggested as a risk factor for prostate cancer, and experimental literature suggests that the carcinogenic effect of cadmium is modified by the presence of zinc. We evaluated total prostate‐specific antigen (PSA) levels in relation to urinary cadmium concentrations and dietary zinc intake.METHODSPSA levels were determined in 1,320 men over the age of 40 in the 2001–2002 National Health and Nutrition Examination Survey (NHANES). Urinary cadmium concentrations were measured in about one‐third of the sample population, whereas dietary zinc intake was based on participants' 24‐hr recall. Information on all three variables was available for 422 men in the 2001–2002 NHANES survey. We performed linear regressions to evaluate the relationships these factors after accounting for age and other covariates.RESULTSLittle evidence for an association between cadmium and elevated PSA level was observed. However, the data provide suggestive evidence for an interaction between zinc intake and cadmium exposure (P for interaction = 0.09). Among men with zinc intake less than the median level of 12.67 mg/day, an increase in 1 µg/g creatinine cadmium exposure was associated with a 35% increase in PSA level. In contrast, among men with greater than median zinc intake, little evidence for an association between cadmium and PSA was found.CONCLUSIONSThese findings suggest a protective effect of zinc intake on cadmium‐induced prostatic injury, and may provide further rationale for investigating the impact of these factors individually and jointly on the etiology of prostate cancer. Prostate 68: 122–128, 2008. © 2007 Wiley‐Liss, Inc.
Return immigration: the chronic migration of Canadian immigrants, 1991, 1996 and 2001
Authors: King Karen M. , Newbold K. Bruce 
Published: November 2007

AbstractRecognizing that immigration is not a one‐time event, the international migration literature has acknowledged return emigration as one option. Typically, international return migrations are evaluated as returns to a country of birth, although they may also involve returns to the host country following a brief sojourn or period outside. However, this form of ‘return’ immigration has received limited attention. Using data drawn from the 1991, 1996 and 2001 Canadian censuses, we examine return immigration, defined here as the immigration act of foreign‐born residents of Canada who have temporarily emigrated from Canada and who subsequently return to Canada. Firstly, we describe the volume and characteristics of Canadian immigrants who undertake return immigration. Secondly, we examine the likelihood of immigrants to undertake a return immigration given their socio‐economic and demographic characteristics. Understanding such return immigrations is one way to an understanding of Canada's attractiveness and ability to retain immigrants. In general, we found the characteristics of return immigrants conformed to general migration theories and the domestic return migration literature. Copyright © 2007 John Wiley & Sons, Ltd.