bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphology of brachial segments in mudpuppy (Necturus maculosus) spinal cord studied with confocal and electron microscopy
Authors: Jovanovic Ksenija , Burke Robert E.
Published: February 2004

The isolated brachial spinal cord of Necturus maculosus is useful for studies of neural networks underlying forelimb locomotion, but information about its cellular morphology is scarce. We addressed this issue by using confocal and electron microscopy. Remarkably, the central region of gray matter was aneural and consisted exclusively of a tenuous meshwork of glial fibers and large extracellular spaces. Somata of motoneurons (MNs) and interneurons (INs), labeled by retrograde transport of fluorescent tracers from ventral roots and axons in the ventrolateral funiculus, respectively, were confined within a gray neuropil layer abutting the white matter borders, whereas their dendrites projected widely throughout the white matter. About one‐third of labeled INs were found contralaterally, with axons crossing ventral to a thick layer of ependyma surrounding the central canal. Lateral MN dendrites proliferated under the pial surface to form a dense, thin (1–2 μm) plexus immediately beneath a thin layer of glial fibrillary acidic protein‐positive glia limitans. The latter contained arrays of unusual tubular structures (diameter 200–400 nm, length 3 μm) that resembled mitochondria but lacked double membranes or cristae. Dorsal roots (DRs) produced dense presynaptic arbors within a wedge‐shaped afferent termination zone medial to the dorsal root entry, within which dendrites of MNs and INs mingled with dense collections of synaptic boutons. Our data suggest that a major fraction of synaptic interactions takes place within the white matter. This study provides a detailed foundation for designing electrophysiological experiments to study the neural circuits involved in locomotor pattern generation. J. Comp. Neurol. 471:361–385, 2004. Published 2004 Wiley‐Liss, Inc.
Presence and induction of the enzyme NAD(P)H: Quinone oxidoreductase 1 in the central nervous system
Authors: Stringer Janet L. , Gaikwad Amos , Gonzales Bianca N. , Long Delwin J. , Marks Latoia M. , Jaiswal Anil K.
Published: February 2004

NAD(P)H:quinone oxidoreductase 1 (NQO1) catalyzes a reductive detoxification that is thought to protect cells against the adverse effects of quinones and related compounds. NQO1 activity is present in all tissues. Absence of the enzyme produces abnormalities in the redox state and seizures, suggesting an important role of the protein in the central nervous system. Immunohistochemical analysis showed that the protein was found throughout the brain of the adult rat and mouse, with complete absence of the protein in brains from NQO1‐/‐ mice. NQO1 was not seen in any neuronal population, but was localized to Bergmann glial in the cerebellum and a subset of the oligodendrocytes throughout the brain. Prolonged seizures induced in adult rats with kainic acid resulted in an increase in activity of the enzyme throughout the brain, most prominently in the cerebellum, but immunoreactivity did not appear in neurons. Comparison of the axons in the corpus callosum from a wild‐type mouse to a knockout mouse showed that myelin is produced in the absence of NQO1, but there appears to be more small‐diameter axons in the knockout animal. These results suggest that NQO1 has a role in myelination in the central nervous system or in the insulating/wrapping function of glial cells. J. Comp. Neurol. 471:289–297, 2004. © 2004 Wiley‐Liss, Inc.
Mixing in simple models for turbulent diffusion
Authors: Tabak Esteban G. , Tal Fabio A.
Published: February 2004

Simple turbulent diffusive models are proposed as conceptual tools for exploring scenarios involving mixing of stratified flows. Applications include the dynamics of the ocean's top mixed layer, shear instability, breaking internal waves, and turbulent stirring of sharp interfaces. A novel measure of mixing is developed, based on arguments from statistical physics. It is shown that, under turbulent diffusion, this measure grows, and that there are strong indications that, under stirring, flows tend to settle down at a maximum of this measure, subject to global dynamical constraints. © 2004 Wiley Periodicals, Inc.
Adiabatic charge transport and the Kubo formula for Landau‐type Hamiltonians
Authors: Elgart Alexander , Schlein Benjamin
Published: February 2004

The adiabatic charge transport is investigated in a two‐dimensional Landau model perturbed by a bounded potential at zero temperature. We show that if the Fermi level lies in a spectral gap, then in the adiabatic limit the accumulated excess Hall charge is given by the linear response Kubo‐Štreda formula. The proof relies on the expansion of Nenciu, some generalized phase space estimates, and a bound on the speed of propagation. © 2004 Wiley Periodicals, Inc.
Parallel LU factorization of sparse matrices on FPGA‐based configurable computing engines
Authors: Wang Xiaofang , Ziavras Sotirios G.
Published: February 2004

Configurable computing, where hardware resources are configured appropriately to match specific hardware designs, has recently demonstrated its ability to significantly improve performance for a wide range of computation‐intensive applications. With steady advances in silicon technology, as predicted by Moore's Law, Field‐Programmable Gate Array (FPGA) technologies have enabled the implementation of System‐on‐a‐Programmable‐Chip (SOPC or SOC) computing platforms, which, in turn, have given a significant boost to the field of configurable computing. It is possible to implement various specialized parallel machines in a single silicon chip. In this paper, we describe our design and implementation of a parallel machine on an SOPC development board, using multiple instances of a soft IP configurable processor; we use this machine for LU factorization. LU factorization is widely used in engineering and science to solve efficiently large systems of linear equations. Our implementation facilitates the efficient solution of linear equations at a cost much lower than that of supercomputers and networks of workstations. The intricacies of our FPGA‐based design are presented along with tradeoff choices made for the purpose of illustration. Performance results prove the viability of our approach. Copyright © 2004 John Wiley & Sons, Ltd.
A comparison of concurrent programming and cooperative multithreading under load balancing applications
Authors: Maris Justin T. , Keen Aaron W. , Ishihara Takashi , Olsson Ronald A.
Published: February 2004

Two models of thread execution are the general concurrent programming execution model (CP) and the cooperative multithreading execution model (CM). CP provides nondeterministic thread execution where context switches occur arbitrarily. CM provides threads that execute one at a time until they explicitly choose to yield the processor. This paper focuses on a classic application to reveal the advantages and disadvantages of load balancing during thread execution under CP and CM styles; results from a second classic application were similar. These applications are programmed in two different languages (SR and Dynamic C) on different hardware (standard PCs and embedded system controllers). An SR‐like run‐time system, DesCaRTeS, was developed to provide interprocess communication for the Dynamic C implementations. This paper compares load balancing and non‐load balancing implementations; it also compares CP and CM style implementations. The results show that in cases of very high or very low workloads, load balancing slightly hindered performance; and in cases of moderate workload, both SR and Dynamic C implementations of load balancing generally performed well. Further, for these applications, CM style programs outperform CP style programs in some cases, but the opposite occurs in some other cases. This paper also discusses qualitative tradeoffs between CM style programming and CP style programming for these applications. Copyright © 2004 John Wiley & Sons, Ltd.
OpenMP‐oriented applications for distributed shared memory architectures
Authors: Marowka Ami , Liu Zhenying , Chapman Barbara
Published: February 2004

The rapid rise of OpenMP as the preferred parallel programming paradigm for small‐to‐medium scale parallelism could slow unless OpenMP can show capabilities for becoming the model‐of‐choice for large scale high‐performance parallel computing in the coming decade.

The main stumbling block for the adaptation of OpenMP to distributed shared memory (DSM) machines, which are based on architectures like cc‐NUMA, stems from the lack of capabilities for data placement among processors and threads for achieving data locality. The absence of such a mechanism causes remote memory accesses and inefficient cache memory use, both of which lead to poor performance.

This paper presents a simple software programming approach called copy‐inside–copy‐back (CC) that exploits the data privatization mechanism of OpenMP for data placement and replacement. This technique enables one to distribute data manually without taking away control and flexibility from the programmer and is thus an alternative to the automat and implicit approaches. Moreover, the CC approach improves on the OpenMP‐SPMD style of programming that makes the development process of an OpenMP application more structured and simpler.

The CC technique was tested and analyzed using the NAS Parallel Benchmarks on SGI Origin 2000 multiprocessor machines. This study shows that OpenMP improves performance of coarse‐grained parallelism, although a fast copy mechanism is essential. Copyright © 2004 John Wiley & Sons, Ltd.
Resilient infrastructure for network security
Authors: Williamson Matthew M.
Published: February 2004

Present‐day network security mechanisms are based on preventing attacks and responding to them as they occur. In the time before a response is implemented the attack is generally free to damage the system. Because responses are usually human driven, this time is long and the damage can be large. One way to minimize this damage is to create “resilient infrastructure.” This is infrastructure that automatically slows attacks, so buying time for a human response. This article argues the case for resilient infrastructure in network security. © 2004 Wiley Periodicals, Inc. Complexity 9: 34–40, 2004
Axial macrosegregation in Ga‐doped germanium grown by the vertical gradient freeze technique with a rotating magnetic field
Authors: Bellmann M. , Pätzold O. , Wunderwald U. , Cröll A.
Published: February 2004

The impact of a rotating magnetic field (RMF) on the axial segregation in Vertical Gradient Freeze (VGF) grown, Ga doped germanium is investigated. Growth experiments were performed using the VGF‐RMF as well as the conventional VGF technique. Carrier concentration profiles characterising the Ga segregation were measured by the Spreading Resistance method and calibrated using Hall values of carrier concentration and mobility. The Ga concentration rises more gradually under RMF action, i.e., the dopant segregation is significantly reduced by the rotating field. This effect is attributed to a better mixing of the melt. Numerical results on the flow velocity confirm this explanation. The RMF induced flow is much more intense than the natural buoyant convection due to the radial temperature gradient and leads to a pronounced decrease of the effective partition coefficient keff. In the early stages of growth a keff value close to k0 was obtained, i.e., the gallium was almost homogeneously distributed within the melt. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
PbS crystals with clover‐like structure: Preparation, characterization, optical properties and influencing factors
Authors: Ni Yonghong , Liu Hongjiang , Wang Fei , Liang Yongye , Hong Jianming , Ma Xiang , Xu Zheng
Published: February 2004

A new and simple route to synthesize Lead sulfide (PbS) crystals with the clover‐like structure was described in the current paper. PbS was prepared in a simple aqueous solution employing (CH3COO)2Pb and thiourea as the initial materials under 130 W microwave irradiation. No any surfactant or template including organic polyamines with N‐chelation property was needed. The phase and composition of the product were identified by X‐ray powder diffraction (XRD) and X‐ray photoelectron spectra (XPS). TEM observation showed that the product with the six‐petal flower‐shaped structures was obtained, but SEM observation confirmed the clover‐like structure of the product; and the six‐petal flowers were formed via the overlap of two clovers revolved 60° around the center of the flower. Some factors affected the shape of the final product were studied and the optical properties of PbS crystals with the clover‐like structure were measured. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A study of primary nucleation of calcium oxalate monohydrate: II. Effect of urinary species
Authors: El‐Shall H. , Jeon Jin‐hwan , Abdel‐Aal E. A. , Khan S. , Gower L. , Rabinovich Y.
Published: February 2004

Kidney stones consist of various organic and inorganic compounds. Calcium oxalate monohydrate (COM) is the main inorganic constituent of kidney stones. However, the mechanisms for the formation of calcium oxalate kidney stones are not well understood. In this regard, there are several hypotheses including nucleation, crystal growth and/or aggregation of formed COM crystals. The effect of some urinary species such as oxalate, calcium, citrate, and protein on nucleation and crystallization characteristics of COM is determined by measuring the weight of formed crystals and their size distributions under different chemical conditions, which simulate the urinary environment. Statistical experimental designs are used to determine the interaction effects among various factors. The data clearly show that oxalate and calcium promote nucleation and crystallization of COM. This is attributed to formation of a thermodynamically stable calcium oxalate monohydrate resulting from supersaturation. Citrate, however, inhibits nucleation and further crystal growth. These results are explained on the basis of the high affinity of citrate to combine with calcium to form soluble calcium citrate complexes. Thus, citrate competes with oxalate ion for binding to calcium cations. These conditions decrease the amount of free calcium ions available to form calcium oxalate crystals. In case of protein (mucin), however, the results suggest that no significant effect could be measured of mucin on nucleation and crystal growth. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimisation of chromium doping in LiNbO3 single crystals
Authors: Kar S. , Bhatt R. , Bartwal K. S. , Wadhawan V. K.
Published: February 2004

Growth of undoped and Cr doped (0.1, 0.25 and 0.5 mol % Cr2O3) congruently‐ melting‐composition LiNbO3 single crystals by Czochralski technique is reported. Chromium doping was optimised to get crystals with potential for an integrated, broadband, tunable laser in the 700‐1100 nm spectral range. Typical sizes of the grown crystals are 25‐30 mm in diameter and 30‐40 mm in length. Symmetrical and sharp conoscopy pictures confirm the optical homogeneity of the crystals. Optical transmission was recorded for both undoped and doped crystals. 70% transmittance was observed. The grown crystals have reasonably good laser damage threshold. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tetrahedral site of Fe(III) and Cu(II) in renierite
Authors: Rama Subba Reddy R. , Fayazuddin Md. , Siva Reddy G. , Lakshmi Reddy S. , Sambasiva Rao P. , Reddy B. J. , Nieto Garcia F.
Published: February 2004

Renierite from Congo is used in the present investigations. It contains only two transition elements iron and copper. EPR results indicate the presence of Fe(III) and Cu(II) with g values 2.03 and 2.40 respectively. Optical absorption spectrum shows several energies in UV‐Vis and NIR region. These energies indicate both Fe(III) and Cu(II) in tetrahedral site. IR spectrum confirms the presence of sulphate and hydroxyl groups in the mineral. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystal structure refinement of CuxAg1‐xInTe2 bulk material determined from X‐ray powder diffraction data using the Rietveld method
Authors: Moustafa A. M. , El‐Sayad E. A. , Sakr G. B.
Published: February 2004

The influence of the Cu‐content in the quaternary compounds CuxAg1‐xInTe2 (0 ≤ x ≤1) on the structural properties of the bulk material was discussed. Bulk ingot materials of CuxAg1‐xInTe2 solid solutions (x = 0.0, 0.25, 0.50, 0.75 and 1.0) have been synthesized by fusion of the constituent elements in the stoichiometric ratios in vacuum‐sealed silica tubes. The materials compositions were confirmed by using energy dispersive analysis of X‐rays (EDAX). X‐ray powder diffraction measurements were performed for all the prepared samples at 300 K in step scanning mode. The analysis of X‐ray data has indicated that the crystal structure of the prepared materials with different compositions is single‐phase polycrystalline materials corresponding to the tetragonal chalcopyrite structure with space group I$ \bar 4 $2d. The crystal structural parameters were refined by Rietveld method using the Full Prof program. The refined lattice constants (a and c), anion positional parameter, u, and the determined bond distances and angles were found to vary with composition, x, attaining zero tetragonal distortion at x ≈ 0.75, which corresponds to an ideal tetragonal unit cell. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multinationals and corporate social responsibility in developing countries: a case study of Nigeria
Authors: E. Ite Uwem
Published: February 2004

Corporate social responsibility (CSR) has a powerful potential to make positive contributions to addressing the needs of disadvantaged communities in developing countries. On the other hand, there are ways in which CSR could, whether by mistake or design, damage the same communities, politically, socially and economically. This paper presents evidence that demonstrates that although there is a good business case for Shell to contribute to poverty alleviation in the Niger Delta, Nigeria, there is also a danger that in the long term Shell could effectively be leading the pace of, and directing the paths to, socio‐economic development in the region with little or no contribution from the Nigerian government. The paper concludes that lack of national macro‐economic planning and management, backed by equitable resource allocation, and an enabling environment, have significant implications for the overall performance of CSR initiatives by multinational corporations (MNCs) in developing countries. In other words, if the macro‐economy is under‐performing due to government failure, there is a likelihood that the contributions of MNCs to poverty alleviation could fail to achieve the desired outcomes. Good governance in all its dimensions is therefore an important component of the CSR agenda. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment.
Corporate social responsibility and the mining industry: conflicts and constructs
Authors: Jenkins Heledd
Published: February 2004

In response to widespread and increasing criticism, the mining industry has started to pay serious attention to its environmental and social impacts. This has recently manifested itself in the formulation of corporate social responsibility (CSR) policies and strategies and a proliferation of CSR, environmental, sustainability and community reporting. Several brief case studies are used to illustrate the issues and conflicts that arise between mining company operations and the environment and community, and how these have led to the development of corporate strategies to deal with environment and community issues. The paper then examines mining company reports, revealing the language and constructs used by the mining industry to frame its responsibility to the environment and community and role in possible conflicts. Companies need to better understand the complex nature of the communities in which they operate in order that suitably tailored strategies are developed. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment.
Environmental reporting by Indian corporations
Authors: Sahay A.
Published: February 2004

Environmental management has entered boardrooms, factories and business premises with economic, social and legal consequences. Sound environmental management provides corporations with a competitive advantage in addition to fulfilling corporate social responsibility and adding value to the business. The command and control policy of governments, the world over, has not produced the desired result. Corporate environmental reporting is emerging as a tool for the same. Indian corporations, like their counterparts in developed countries, took hesitant steps towards environmental protection – most of them driven by legal compliance. A selected few companies, however, took to environmental protection, enhancement and reporting through overall business considerations. The study indicates that environmental reporting, barring a few cases, is unsystematic and non‐comparable. Though good work is being done by some industrial sectors and some units in different sectors, the reports seem to be aimed more at publicity than providing environmental facts and figures. A good quality of environmental reporting, like good environmental performance, needs to be encouraged and rewarded. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment.
Monitoring of monocyte functional state after extracorporeal circulation: A flow cytometry study
Authors: Sbrana Silverio , Parri Maria Serena , De Filippis Rossella , Gianetti Jacopo , Clerico Aldo
Published: February 2004

Background

Cardiovascular surgery with cardiopulmonary bypass (CPB) induces systemic inflammation and postoperative complications depending on pro‐ and anti‐inflammatory mechanisms. Activated polymorphonuclear cells and monocytes may be responsible for morbidity associated with CPB. Knowledge of the monocyte functional state in particular may help to develop protective interventions.

Methods

Samples were drawn from venous peripheral blood (basal condition, at 4 and 24 h after CPB) and coronary blood (before and after cardioplegic arrest) of 14 patients undergoing cardiac surgery. The following phenotypic and functional parameters of the monocyte population were studied by flow cytometry: surface molecules expression (CD18, CD11a, CD11b, CD14, CD15, CD45, HLA‐DR, and Toll‐like receptor [TLR]‐4), myeloperoxidase (MPO) content, and intracellular cytokine production (tumor necrosis factor [TNF]‐α, interleukin [IL]‐1β, IL‐6, and IL‐8).

Results

Cardiac surgery with CPB induced down‐modulation of surface molecules expression on peripheral monocytes, especially at 24 h after CPB, for CD18, CD11a, and CD11b (P < 0.003) and for the CD15 adhesive cluster (P = 0.0028) and HLA‐DR (P < 0.001). At 4 h after CPB, downregulation was observed for CD14 (P = 0.004), CD45 (P = 0.014), and CD15 (P = 0.0056). A loss of MPO was detected in venous peripheral (at 24 h after CPB, P = 0.01) or coronary (at reperfusion, P < 0.02) blood. The CD15 cluster complex exhibited a down‐modulation in coronary blood (at reperfusion, P = 0.0003). Spontaneous intracellular production of IL‐1β, IL‐6, and IL‐8 decreased at 24 h after CPB (P < 0.05).

Conclusions

The down‐modulation of integrins and adhesive receptor expression and the loss of MPO suggest a strong activation and shedding reaction of circulating monocyte after CPB, further exacerbated by contact with coronary ischemic vessels. The changes of differentiation antigens may reflect the appearance of a partially immature population immediately after CPB. The reduced proinflammatory cytokine production, observed at 24 h after CPB, suggests a functional polarization of circulating monocytes. © 2003 Wiley‐Liss, Inc.
Sensitive measurement of fragmented red cell population using flow cytometry, and its application for estimating thrombotic microangiopathy after stem cell transplantation
Authors: Toba Ken , Tsuchiyama Junjiro , Hashimoto Shigeo , Ichida Takafumi , Kato Kiminori , Watanabe Kenichi , Furukawa Tatsuo , Narita Miwako , Takahashi Masuhiro , Aizawa Yoshifusa
Published: February 2004

Background

Thrombotic microangiopathy (TMA) is one of the lethal complications after hematopoietic stem cell transplantation (SCT). The levels of fragmented red cells (FRCs), thrombomodulin (TM), and factor VIII–related antigen in the blood are the most important markers for estimating TMA. However, the FRC level has been measured by using microscopy and the naked eye; therefore, an improvement in technology to objectively count FRC is necessary.

Methods

We established a novel technique to sensitively measure FRC as glycophorin A dull–positive small particles using a flow cytometer and estimated its reliability in patients treated with SCT. The blood level of FRC was compared with other clinical data in 257 blood samples in 16 clinical courses after SCT of 15 patients.

Results

Sorted glycophorin A dull–positive small particles morphologically showed FRC. Measured FRC percentage had a weak correlation with serum levels of lactate dehydrogenase (LDH) and total bilirubin but not with TM level, whereas TM showed a weak correlation with the levels of aspartate aminotransferase and LDH. In a patient with fulminant TMA, decrement of the FRC level led to improvement in liver parameters after treatment, presumably due to the rapid clearance of FRC, and increased simultaneously with the levels of LDH and bilirubin by the TMA recurrence.

Conclusions

Levels of FRC percentage and TM were independent parameters of TMA. This novel technique may be used as a standard methodology in diagnosing TMA. © 2003 Wiley‐Liss, Inc.
C‐Kit receptor (CD117) expression on myeloblasts and white blood cell counts in acute myeloid leukemia
Authors: Woźniak Jolanta , Kopeć‐Szlęzak Joanna
Published: February 2004

Background

The c‐Kit receptor is considered to play a crucial role in hematopoiesis. Induction of mobilization of hematopoietic cells in the bone marrow requires cooperative signaling through c‐Kit and c‐Kit ligand pathway, and these interactions are important in the retention of stem cells within the bone marrow. Therefore, we analyzed c‐Kit density on the leukemic myeloblasts of patients with acute myeloid leukemia (AML) in relation to white blood cell count (WBC) in the peripheral blood.

Methods

Bone marrow aspirates collected from patients with AML and bone marrow aspirates and leukapheresis products after granulocyte colony‐stimulating factor blood mobilization from adult volunteers were studied. To determine the level of c‐Kit receptor expression, we applied quantitative (relative fluorescence intensity and antibody binding per cell) cytometric methods.

Results

Our data showed negative correlation between the level of c‐Kit expression intensity on myeloblasts and the number of leukocytes in blood of AML patients. The c‐Kit receptor density on myeloblasts in patients with low WBC was significantly stronger than that on myeloblasts in patients with high WBC. In the latter patient group, the density c‐Kit receptor on myeloblasts was similar to that on CD34+ cells in mobilized peripheral blood.

Conclusions

The obtained data suggest an involvement of c‐Kit receptor in the regulation of leukemic myeloblasts egress to the peripheral blood. © 2004 Wiley‐Liss, Inc.
Immunophenotypic analysis of mast cells in mastocytosis: When and how to do it. Proposals of the Spanish Network on Mastocytosis (REMA)
Authors: Escribano Luis , Diaz‐Agustin Beatriz , López Antonio , Núñez López Rosa , García‐Montero Andrés , Almeida Julia , Prados Aranzazu , Angulo Miguel , Herrero Sonia , Orfao Alberto ,   on Behalf of the Spanish Network on Mastocytosis (REMA)
Published: February 2004

Background

Mastocytosis is a term used for a heterogeneous group of disorders characterized by an abnormal proliferation and accumulation of mast cells (MCs) in one or multiple tissues including skin, bone marrow, liver, spleen, and lymph nodes, among others.

Methods

In recent years, multiparameter flow cytometric studies have shown that pathologic MCs from patients with mastocytosis display unique aberrant immunophenotypic characteristics as compared with normal MCs.

Results

Among other features, pathologic MCs show aberrant expression of CD25 and CD2 antigens and abnormally high levels of the CD11c and CD35 complement receptors, the CD59 complement regulatory molecule, the CD63 lysosomal membrane antigen, and the CD69 early‐activation antigen. In addition, MCs from mastocytosis express abnormally low levels of CD117 and unexpectedly high light scatter and autofluorescence characteristics.

Conclusions

These aberrant immunophenotypic features are of great relevance for the assessment of tissue involvement in mastocytosis with consequences in the diagnosis, classification, and follow‐up of the disease and in its differential diagnosis with other entities. In this paper we provide the reader with information for the objective and reproducible identification of pathologic MCs by using quantitative multiparametric flow cytometry, information for their phenotypic characterization, and the criteria currently used for a correct interpretation of the immunophenotypic results obtained. © 2004 Wiley‐Liss, Inc.
Endoscopic ultrasound‐guided fine‐needle aspiration cytology of peripheral nerve‐sheath tumors
Authors: Stelow Edward B. , Lai Rebecca , Bardales Ricardo H. , Linzie Bradley M. , Mallery Shawn , Stanley Michael W.
Published: February 2004

Endoscopic ultrasound (EUS) has allowed for the fine‐needle aspiration and diagnosis of many different gastrointestinal neoplasms, including mesenchymal tumors. Although most mesenchymal tumors of the gastrointestinal tract are gastrointestinal stromal tumors (GISTs), other mesenchymal tumors, including neural tumors, do occur. Proper diagnosis and differentiation of these tumors from GISTs are important because of their different prognoses and treatment regimens. We encountered three peripheral nerve‐sheath tumors of the gastrointestinal tract aspirated by EUS (two schwannomas and a granular‐cell tumor). We report on the endoscopic ultrasound, cytologic, histologic, and immunohistochemical findings of these cases. Diagn. Cytopathol. 2004;30:172–177. © 2004 Wiley‐Liss, Inc.
Exaggerated pigmented granulomatous reaction to the artificial joint implant mimics metastatic melanoma
Authors: Xin Wei , Davenport Robertson D. , Chang Alfred E. , Michael Claire W.
Published: February 2004

Total joint replacement is a common orthopedic procedure. An artificial joint implant may fail due to mechanical mishap and a granulomatous reaction can be induced by the artificial joint debris after the mechanical failure. We report a case of an exaggerated pigmented granulomatous tissue response to metallic artificial joint implant debris in a 72‐yr‐old male that was mistaken for metastatic melanoma. The mass was soft, pigmented, ill‐defined, and located in the right inguinal region. Fine‐needle aspiration revealed numerous black‐pigment laden cells. The cellular features were frequently obscured by the heavy pigmentation. Occasional cells exhibited atypia and prominent nucleoli. There were also abundant extracellular irregular small black particles dispersed in the background. The diagnosis of melanoma involving a lymph node was made. Since there was no prior history of melanoma, it was presumed that this represented metastatic melanoma from an unknown primary. A subsequent exploration of the groin was performed with the intent to resect the disease. At exploration, the mass was found to be contiguous with the hip joint and the frozen section of the mass revealed no evidence of melanoma. The final tissue diagnosis confirmed the frozen section report and showed a granulomatous reaction. This report underscores the diagnostic dilemma associated with the exaggerated pigmented granulomatous reaction due to an artificial prosthesis. Diagn. Cytopathol. 2004;30:198–200. © 2004 Wiley‐Liss, Inc.
Cytologic‐histologic correlations in the diagnosis of inverted sinonasal papilloma
Authors: Gould Victor E. , Manosca Frances , Reddy Vijaya B. , Gattuso Paolo
Published: February 2004

We present cytologic data from multiple samples from two cases of inverted sinonasal papilloma (ISP). These samples displayed the entire spectrum of squamous cell changes, including benign squamous papilloma, variable degrees of dysplasia, and invasive squamous cell carcinoma. In all instances, the cytologic impression coincided with the final diagnosis based on frozen and/or permanent histologic sections from the same samples. We suggest that cytologic examination be viewed as a useful initial approach in the diagnosis of ISP, and in the differential diagnosis of other tumors that occur in the same sites. Diagn. Cytopathol. 2004;30:201–207. © 2004 Wiley‐Liss, Inc.
Systematic temporal variation in the rate of spontaneous eye blinking in human infants
Authors: Bacher Leigh F. , Smotherman William P.
Published: February 2004

The rate of spontaneous eye blinking, a putative index of central dopamine activity based on neuropharmacological and clinical research, has been linked to cognitive activity and behavioral state. Although many species have been studied, few researchers have examined spontaneous eye blinking in human infants. Human infants between 10 and 12 weeks of age were observed before, during, and after a feeding or during attention to visual stimuli. Infants blinked spontaneously several times per minute, and their blinking rate increased during feeding and after the appearance of new visual stimuli. These systematic changes in the rate of spontaneous blinking under controlled conditions suggest that spontaneous blinking rate may reflect reliable variation in central nervous system activity that underlies behavioral and cognitive responses to salient or novel stimuli. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 44: 140–145, 2004.
Associative learning and memory in a chimpanzee fetus: Learning and long‐lasting memory before birth
Authors: Kawai Nobuyuki , Morokuma Seiichi , Tomonaga Masaki , Horimoto Naoki , Tanaka Masayuki
Published: February 2004

We tested whether a chimpanzee fetus could form an association between an extrauterine tone and vibroacoustic stimulation (VAS) using classical conditioning treatment. Two kinds of pure tone were used as the conditioned stimuli, one where a 500‐Hz tone was always followed by a VAS of 80 Hz (110 gal), the unconditioned stimulus (US), and another where a 1000‐Hz tone was never followed by a VAS. This treatment was repeated 156 times in total until natural labor at 233 days of gestational age. Behavioral tests on the 33rd and 58th days after birth revealed a differential response to the tones: The infant displayed an exaggerated response to the 500‐Hz tone, but not to the 1000‐Hz tone. Other naïve chimpanzee infants did not show any response to either tone, which suggests that a chimpanzee fetus can distinguish between tones and form an association, and that it retains such information for at least 2 months after birth. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 44: 116–122, 2004.
Correlated attributes and categorization in the first half‐year of life
Authors: Bhatt Ramesh S. , Wilk Amy , Hill Debra , Rovee‐Collier Carolyn
Published: February 2004

In two experiments with 36 human infants, we asked whether 3‐ and 6‐month‐olds could use correlations between attributes of individual objects to categorize. Infants learned to kick to move block mobiles that simultaneously displayed two categories defined by the figures displayed on them: the colors of the figures and the colors of the blocks. Two features were correlated, and the third varied across categories. Only 6‐month‐olds categorized novel category exemplars that preserved the original feature correlations (Experiment 1A), but both 3‐ and 6‐month‐olds discriminated feature recombinations that broke the original correlations (Experiment 1B). When category exemplars were presented successively, 6‐month‐olds also learned the feature correlations and used them to categorize (Experiment 2), but their performance was less robust. Infants' superior learning when stimuli were presented simultaneously may reflect “unitization,” a learning disposition unique to immature infants. These experiments reveal that infants' ability to use correlated attributes to categorize emerges months earlier than previously thought. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 44: 103–115, 2004.
Localized expression of drm/gremlin in the central nervous system of the chicken embryo
Authors: Huillard Emmanuelle , Marx Maria
Published: February 2004

Drm/Gremlin is a member of the Dan family of bone morphogenetic protein (BMP) antagonists known to function in vertebrate limb outgrowth and lung morphogenesis. Its expression detected in neurons and astrocytes of the adult brain suggested a possible role in brain morphogenesis and/or neuronal versus glial differentiation. To investigate this role, we analysed its expression pattern in the central nervous system of the chicken embryo, by in situ hybridization. In the brain, we found that drm is mainly expressed in the medial pallium in the dorsal telencephalon and in the ventral diencephalon. drm was detected in the meninges of the spinal cord. We also found that drm was expressed in the developing optic nerve and at the optic nerve/pecten junction. In all these territories, distinct bmps are expressed. Taken together, these data suggest that Drm could play a role in the development of the medial pallium and during optic nerve and pecten development by modulating BMP signaling. Developmental Dynamics 229:688–694, 2004. © 2004 Wiley‐Liss, Inc.
In ovo electroporation of avian somites
Authors: Scaal Martin , Gros Jerome , Lesbros Cynthia , Marcelle Christophe
Published: February 2004

In ovo electroporation is a well‐established method of gene transfer into neural and mesenchymal tissue in chick embryos. Electroporation of somites, however, has been hampered by low efficiency due to technical difficulties. Here, we present a powerful technique to electroporate avian somites and subpopulations of somitic cells at high efficiency in ovo. We demonstrate specific targeting of distinct somitic compartments and their derivatives using single or combinations of plasmid expression vectors. This technique opens new perspectives to investigate the morphologic and genetic basis of somite development. Developmental Dynamics 229:643–650, 2004. © 2004 Wiley‐Liss, Inc.
NeuroD induces the expression of visinin and calretinin by proliferating cells derived from toxin‐damaged chicken retina
Authors: Fischer Andy J. , Wang Shu‐Zhen , Reh Thomas A.
Published: February 2004

Müller glia have been shown to be a potential source of neural regeneration in the avian retina. In response to acute damage Müller glia de‐differentiate, proliferate, express transcription factors found in embryonic retinal progenitors, and some of the progeny differentiate into neurons and glia (Fischer and Reh [2001a] Nat. Neurosci. 4:247–252). However, most of the cells produced by proliferating Müller cells appear to remain undifferentiated. The purpose of this study was to test whether the neurogenic gene NeuroD can promote the differentiation of proliferating cells derived from the postnatal chick retina. We used recombinant avian retroviruses to transfect green fluorescent protein (GFP) or NeuroD. The majority of cells transfected with GFP remained undifferentiated, with a few cells differentiating into calretinin‐immunoreactive neurons. Many cells transfected with the NeuroD‐virus expressed calretinin, neurofilament, or visinin, while most cells remained undifferentiated. The number of calretinin‐expressing cells that were generated was increased approximately 20‐fold with forced expression of NeuroD. In addition, we found that cells transfected with NeuroD never expressed glutamine synthetase, a marker of mature Müller glia, suggesting that NeuroD suppresses glial differentiation. We conclude that NeuroD stimulates cells from the toxin‐damaged chicken retina to acquire some neuronal phenotypes. We propose that most of these cells were derived from Müller glia. Developmental Dynamics 229:555–563, 2004. © 2004 Wiley‐Liss, Inc.
Dynamic patterns of apoptosis in the developing chicken heart
Authors: Schaefer Katherine S. , Doughman Yong Qiu , Fisher Steven A. , Watanabe Michiko
Published: February 2004

The outflow tract (OFT) is abnormal in many congenital heart defects. One critical mechanism for morphogenesis of this complex structure is apoptosis. Chicken embryos (stages 19–38; ED4–10) stained with a fluorescent supravital lysosomal dye (LysoTracker Red; LTR) revealed the three‐dimensional relationship between structural changes and apoptosis. The LTR staining peaked in the OFT myocardium at stages 27–32, consistent with our previous analyses using other apoptosis assays. While LTR stained under both the pulmonary artery and the aorta, it was most prevalent in the subaortic myocardium before its elimination. Furthermore, LTR staining was most abundant in the myocardium under intensely cytokeratin‐positive, thick epicardium. These data support the hypothesis that temporally and spatially restricted apoptosis in the OFT myocardium allows the aorta and pulmonary artery to dock at the appropriate angle and level with the proper ventricle. These data also support a relationship between the differentiating epicardium and cardiomyocyte apoptosis. Developmental Dynamics 229:489–499, 2004. © 2004 Wiley‐Liss, Inc.
A primer on using in ovo electroporation to analyze gene function
Authors: Krull Catherine E.
Published: February 2004

The chicken embryo has served as a classic model system for developmental studies due to its easy access for surgical manipulations and a wealth of data about chicken embryogenesis. Notably, the mechanisms controlling limb development have been explored best in the chick. Recently, the method of in ovo electroporation has been used successfully to transfect particular cells/tissues during embryonic development, without the production or infectivity associated with retroviruses. With the sequencing of the chicken genome near completion, this approach will provide a powerful opportunity to examine the function of chicken genes and their counterparts in other species. In ovo electroporation has been most effectively used to date for ectopic or overexpression analyses. However, recent studies indicate that this approach can be used successfully for loss‐of‐function analyses, including protein knockdown experiments with morpholinos and RNAi. Here, I will discuss parameters for using in ovo electroporation successfully to study developmental processes. Developmental Dynamics 229:433–439, 2004. © 2004 Wiley‐Liss, Inc.
Characterization of chicken Nf2/merlin indicates regulatory roles in cell proliferation and migration
Authors: Chen Y. , Gutmann D.H. , Haipek C.A. , Martinsen B.J. , Bronner‐Fraser M. , Krull C.E.
Published: February 2004

The neurofibromatosis 2 (NF2) tumor suppressor protein merlin, or schwannomin, functions as a negative growth regulator such that inactivating mutations in Nf2 predispose humans to tumors. In addition, merlin has a critical role during embryonic development. Nf2‐deficient mice die early during embryogenesis, with defects in gastrulation and extraembryonic tissues. To investigate the function of Nf2/merlin during embryonic development, we first identified the homologous Nf2 gene in chicken (cNf2) and examined the distribution of chicken merlin (c‐merlin) during myogenesis. cNf2 encoded a full‐length mRNA of 1,770 nucleotides and a protein of 589 residues. C‐merlin shared high sequence homology and common protein motifs with vertebrate and Drosophila merlins. In addition, cNF2 functions as a negative growth regulator similar to human and Drosophila merlin in vitro. In vivo, c‐merlin was expressed diffusely in the forming dermomyotome but down‐regulated in migratory muscle precursors in the forelimb. As muscle formed in the limb, c‐merlin expression was up‐regulated. As an initial examination of c‐merlin function during myogenesis, c‐merlin was ectopically expressed in muscle precursors and the effects on muscle development were examined. We show that ectopic merlin expression reduces the proliferation of muscle precursors as well as their ability to migrate effectively in limb mesoderm. Collectively, these results demonstrate that c‐merlin is developmentally regulated in migrating and differentiating myogenic cells, where it functions as a negative regulator of both muscle growth and motility. Developmental Dynamics 229:541–554, 2004. © 2004 Wiley‐Liss, Inc.
Dynamic expression of Lef/Tcf family members and β‐catenin during chick gastrulation, neurulation, and early limb development
Authors: Schmidt Maike , Patterson Margaret , Farrell Elizabeth , Münsterberg Andrea
Published: February 2004

Members of the Lef/Tcf family of HMG‐box transcription factors mediate the response to Wnt as part of the canonical Wnt signaling cascade. Positive and negative cofactors, including β‐catenin, CtBP, and Smad3, regulate the activity of Lef/Tcf transcription complexes. Interaction of Lef/Tcfs with β‐catenin results in target gene activation or repression, depending on the context. Here, we report the cloning of a novel chick Tcf‐1 splice variant and of a partial cDNA for chick Tcf‐3. We describe their expression patterns during early development and have compared them with the expression profiles of Lef‐1 and β‐catenin. We found restricted patterns during gastrulation, neurulation, somitogenesis, and early limb development. β‐catenin and Lef/Tcf expression did not always coincide, indicating developmental contexts in which Lef/Tcf proteins may interact with other cofactors and conversely, the areas in which β‐catenin may interact with other coregulators, or be involved in regulating adhesive properties of cells. Developmental Dynamics 229:703–707, 2004. © 2004 Wiley‐Liss, Inc.
Enteric nervous system patterning in the avian hindgut
Authors: Doyle Adele M. , Roberts Drucilla J. , Goldstein Allan M.
Published: February 2004

The enteric nervous system (ENS) is principally derived from vagal and sacral neural crest cells that migrate throughout the gastrointestinal tract before differentiating into neurons and glia. These cells form two concentric rings of ganglia and regulate intestinal motility, absorption, and secretion. Abnormalities of ENS development can lead to disorders of intestinal function, including Hirschsprung's disease. These disorders are generally limited to the distal hindgut, suggesting unique features to development of this region. This study characterized the normal spatiotemporal development of the ENS within the avian hindgut. Neural crest cells begin to populate the hindgut at E8, with patterning of both plexuses complete by embryonic day 9. Crest‐derived cells arrive in the submucosal layer before the myenteric layer, as well as differentiate to a neuronal phenotype first. The cloaca demonstrates a unique pattern, characterized by a disorganized myenteric plexus and a flattened nerve of Remak. Detailed understanding of normal avian hindgut ENS development will allow better utilization of this model system to study abnormalities of the intestinal nervous system. Developmental Dynamics 229:708–712, 2004 © 2004 Wiley‐Liss, Inc.