bluuebunny/crossref_metadata_2025 huggingface dataset:
Associations between the morphology and physiology of ventral‐horn neurons in the adult turtle
Authors: McDonagh Jennifer C. , Hornby T. George , Reinking Robert M. , Stuart Douglas G.
Published: November 2002

This study compared some morphologic and physiological properties of adult turtle spinal motoneurons (MNs) vs. interneurons (INs). Reconstructions were made of 20 biocytin‐stained cells, which had been previously studied physiologically in 2‐mm‐thick slices of lumbosacral spinal cord. The intracellularly measured physiological properties included resting potential, input resistance (RN), threshold (rheobase, IRh), and slope of the stimulus current (I) ‐spike frequency (f) relation. The seven morphologic properties that were quantified for each cell included three indices of somal size (diameter, area, volume), and four of dendritic size: the number of first‐ and last‐order branches, rostrocaudal extent, and Σ individual lengths. Significant differences were shown between all seven morphologic parameters for MNs vs. INs. Despite the small sample size, significant differences were also shown for five of seven parameters for high‐threshold vs. low‐threshold MNs, and three of seven for low‐threshold MNs vs. INs. These latter three parameters were the number of terminal dendritic branches, their rostrocaudal extent, and the Σ dendritic lengths. Linear associations for the MN + IN and the MN samples were stronger between the four dendritic parameters than between soma‐dendritic ones. Exponential associations between morphologic and physiological properties were mostly significant (28 of 30), and their strength was in the order IRh< RN< f/I slope for the MN +IN sample and IRh< RN= f/I slope for the MN sample. There is discussion of the relevance of the above findings to the provisional classification of turtle ventral‐horn neurons on the basis of electrophysiology alone. J. Comp. Neurol. 454:177–191, 2002. © 2002 Wiley‐Liss, Inc.
Expression of nitric oxide synthase and nitric oxide‐sensitive guanylate cyclase in the crustacean cardiac ganglion
Authors: Scholz Nathaniel L. , Labenia Jana S. , De Vente Jan , Graubard Katherine , Goy Michael F.
Published: November 2002

The cardiac ganglion is a simple central pattern‐generating network that controls the rhythmic contractions of the crustacean heart. Enzyme assays and Western blots show that whole heart homogenates from the crab Cancer productus contain high levels of nitric oxide synthase (NOS), an enzyme that catalyzes the conversion of arginine to citrulline with concomitant production of the transmitter nitric oxide (NO). Crab heart NOS is calcium‐dependent and has an apparent molecular weight of 110 kDa. In the cardiac ganglion, antibodies to NOS and citrulline indicate the presence of a NOS‐like protein and NOS enzymatic activity in the four small pacemaker neurons and the five large motor neurons of the cardiac network. In addition, all cardiac neurons label positively with an antibody to cyclic guanosine monophosphate (cGMP). The NO donor sodium nitroprusside (SNP, 10 mM) stimulates additional cGMP production in the isolated ganglion. This increase is blocked by [1H](1,2,4)oxadiazole(4,3‐a)quinoxalin‐1‐one (ODQ, 50 μM), an inhibitor of the NO‐sensitive soluble guanylate cyclase (sGC). Taken together, our data indicate that NO‐ and cGMP‐mediated signaling pathways are enriched in the cardiac system relative to other crab tissues and that the cardiac network may be a target for extrinsic and intrinsic neuromodulation via NO produced from the heart musculature and individual cardiac neurons, respectively. The crustacean cardiac ganglion is therefore a promising system for studying cellular and synaptic mechanisms of nitrergic neuromodulation in a simple pattern‐generating network. J. Comp. Neurol. 454:158–167, 2002. © 2002 Wiley‐Liss, Inc.
Horizontal cell density and mosaic regularity in pigmented and albino mouse retina
Authors: Raven Mary A. , Reese Benjamin E.
Published: November 2002

The present study has examined the density and mosaic regularity of the population of horizontal cells in the pigmented and albino mouse retina. Retinal wholemounts were immunostained for calbindin, and labeled cells within sampled fields were analyzed to determine horizontal cell soma size and density. The X‐Y positional coordinates of each cell were determined, from which the geometrical properties of the mosaic were examined using nearest neighbor and Voronoi domain analyses, and regularity indices were derived from those measures. Autocorrelation and density recovery profile analyses were also conducted to identify the presence of exclusion zones within the population of horizontal cells. For each sampled field, random simulations of matched density, constrained by the physical size of the horizontal cells, were generated and analyzed in parallel. Neither retinal area, nor horizontal cell soma size, nor density differed between the pigmented and albino retinas. Mosaic regularity in pigmented and albino retinas did not differ, but each differed significantly from random simulations of identical density. Horizontal cells in the mouse retina exhibit exclusion zones extending beyond the physical size of the soma, but these were identical in size in the pigmented and albino retina. Such exclusion zones are suggested to reflect homotypic interactions between horizontal cells during early development that mediate cellular repulsion and tangential movement. The lack of any discernable effect brought about by the albino mutation, despite numerous developmental abnormalities associated with the retinal neuroepithelium in albino mice, is consistent with other results showing that homotypic interactions are sufficient for the genesis of the global patterning characteristic of mature retinal mosaics. J. Comp. Neurol. 454:168–176, 2002. © 2002 Wiley‐Liss, Inc.
Cystitis‐induced upregulation of tyrosine kinase (TrkA, TrkB) receptor expression and phosphorylation in rat micturition pathways
Authors: Qiao Li‐Ya , Vizzard Margaret A.
Published: November 2002

This study examined tyrosine kinase receptor (Trk) expression and phosphorylation in lumbosacral dorsal root ganglia (DRG) after acute (8 or 48 hours) or chronic (10 days) cyclophosphamide (CYP)–induced cystitis. Increases in the number of TrkA‐immunoreactive (IR) cell profiles were detected in the L1 and L6 DRG (four‐fold; P ≤ 0.01) and the S1 DRG (1.5‐fold; P ≤ 0.05) but not in the L2, L4, and L5 DRG with CYP‐induced cystitis of acute and chronic duration compared with control rats. The number of TrkB‐IR cell profiles increased in the L1 and L2 DRG (L1: 2.6‐fold; L2: 1.4‐fold; P ≤ 0.05) and in the L6 and S1 DRG (L6: 2.2‐fold; S1: 1.3‐fold; P ≤ 0.05) only after acute CYP treatment (8 hours). After CYP treatment, the percentage of bladder afferent cell profiles expressing TrkA‐IR (∼50%; P ≤ 0.05) increased in L1 and L6 DRG. The percentage of bladder afferent cell profiles expressing TrkB‐IR (∼45%; P ≤ 0.05) in L1, L2, L6, and S1 DRG also increased compared with control cell profiles. The increase in TrkA‐IR in bladder afferent cells occurred 8 hours after CYP treatment and was maintained in L1 DRG with chronic (10 days) CYP‐induced cystitis. However, the increase in bladder afferent cells expressing TrkB‐IR only occurred at the most acute time point examined (8 hours). TrkA‐IR and TrkB‐IR cell profiles also demonstrated phosphorylated Trk‐IR with acute and/or chronic CYP‐induced cystitis. These results demonstrated that CYP‐induced cystitis increases the expression and phosphorylation of Trk receptors in lumbosacral DRG. Expression of neurotrophic factors in the inflamed urinary bladder may contribute to this increased expression, and neurotrophic factor and Trk interactions may play unique roles in decreased urinary tract plasticity with CYP‐induced cystitis. J. Comp. Neurol. 454:200–211, 2002. © 2002 Wiley‐Liss, Inc.
Finding all solutions of piecewise‐linear resistive circuits using the dual simplex method
Authors: Yamamura Kiyotaka , Tanaka Shigeru
Published: November 2002

An efficient algorithm is proposed for finding all solutions of piecewise‐linear (PWL) resistive circuits using linear programming (LP). This algorithm is based on a simple test (termed the LP test) for non‐existence of a solution to a system of PWL equations in a given region. In the conventional LP test, the system of PWL equations is transformed into an LP problem, to which the simplex method is applied. However, this algorithm requires a very large number of pivotings because the simplex method is applied on many regions. In this paper, we introduce the dual simplex method to the LP test, which makes the average number of pivotings per region much smaller (less than one, for example) and makes the algorithm very efficient. By numerical examples, it is shown that the proposed algorithm could find all solutions of large‐scale problems, including those where the number of variables is 300 and the number of linear regions is 10300, in practical computation time. Copyright © 2002 John Wiley & Sons, Ltd.
On complete stability of linear and quadratic programming neural networks
Authors: Forti Mauro
Published: November 2002

The paper addresses complete stability (CS) of the important class of neural networks to solve linear and quadratic programming problems introduced by Kennedy and Chua (IEEE Trans. Circuits Syst., 1988; 35: 554). By CS it is meant that each trajectory converges to a stationary state, i.e. an equilibrium point of the neural network. It is shown that the neural networks in (IEEE Trans. Circuits Syst., 1988; 35: 554) enjoy the property of CS even in the most general case where there are infinite non‐isolated equilibrium points. This result, which is proved by exploiting a new method to analyse CS (Int. J. Bifurcation Chaos 2001; 11: 655), extends the stability analysis by Kennedy and Chua (IEEE Trans. Circuits Syst., 1988; 35: 554) to situations of interest where the optimization problems have infinite solutions. Copyright © 2002 John Wiley & Sons, Ltd.
A DSP‐like analogue processing unit for smart image sensors
Authors: Dupret Antoine , Klein Jacques‐Olivier , Nshare Abdallah
Published: November 2002

An electronic retina featuring DSP‐like programmable analogue processing is addressed. The motivations for designing such an original smart image sensor are accounted for. The architecture of the circuit is described and then the two more important building blocks are detailed. Finally, the practical implementation and tests results are given so as to validate the approach. Copyright © 2002 John Wiley & Sons, Ltd.
Guiding a mobile robot with cellular neural networks
Authors: Vilasís‐Cardona Xavier , Luengo Sonia , Solsona Jordi , Maraschini Alessandro , Apicella Giada , Balsi Marco
Published: November 2002

We show how cellular neural networks (CNNs) are capable of providing the necessary signal processing needed for visual navigation of an autonomous mobile robot. In this way, even complex feature detection and object recognition can be obtained in real time by analogue hardware, making fully autonomous real‐time operation feasible. An autonomous robot was first simulated and then implemented by simulating the CNN with a DSP. The robot is capable of navigating in a maze following lines painted on the floor. Images are processed entirely by a CNN‐based algorithm, and navigation is controlled by a fuzzy‐rule‐based algorithm. Copyright © 2002 John Wiley & Sons, Ltd.
Hyperchaotic behaviour of two bi‐directionally coupled Chua's circuits
Authors: Cannas Barbara , Cincotti Silvano
Published: November 2002

In this paper, a non‐linear bi‐directional coupling of two Chua's circuits is presented. The coupling is obtained by using polynomial functions that are symmetric with respect to the state variables of the two Chua's circuits. Both a transverse and a tangent system are studied to ensure a global validity of the results in the state space. First, it is shown that the transverse system is an autonomous Chua's circuit, which directly allows the evaluation of the conditions on its chaotic behaviour, i.e. the absence of synchronization between the coupled circuits. Moreover, it is demonstrated that the tangent system is also a Chua's circuit, forced by the transverse system; therefore, its dynamics is ruled by a time‐dependent equation. Thus, the calculus of conditional Lyapunov exponents is necessary in order to exclude antisynchronization along the tangent manifold.

The properties of the transverse and tangent systems simplify the study of the coupled Chua's circuits and the determination of the conditions on their hyperchaotic behaviour. In particular, it is shown that hyperchaotic behaviour occurs for proper values of the coupling strength between the two Chua's circuits. Finally, numerical examples are given and discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Characterization of foam cells in nipple aspirate fluid
Authors: Krishnamurthy S. , Sneige N. , Ordóñez N.G. , Hunt K.K. , Kuerer H.M.
Published: November 2002

Foam cells with abundant vacuolated cytoplasm are prominent in most samples of spontaneous nipple discharge, nipple aspirate fluid, and ductal lavage. Although several investigators have attempted to characterize these cells, there is no consensus about whether these cells are derived entirely from macrophages or from both ductal epithelial cells and macrophages. Using immunocytochemical methods, we studied 20 paired specimens of nipple aspirate fluid containing abundant foam cells obtained from the involved breast of women with in situ or invasive carcinoma and from the contralateral normal breast. We used a cocktail of anticytokeratin antibodies including AE1, AE3, and CAM5.2 and the macrophage marker KP1 (CD68). In addition, we examined samples by electron microscopy. The foam cells were consistently negative for cytokeratin and positive for CD68. In every case electron microscopy of these cells revealed irregular outlines with short cytoplasmic processes. The cytoplasm was abundant and contained numerous lysosomes, a small Golgi complex, lipid droplets, mitochondria, and short profiles of rough endoplasmic reticulum. There was no evidence, however, of cell junctions or tonofilaments. The immunocytochemical and electron microscopic findings of our study together clearly support a macrophage derivation for foam cells in nipple aspirate fluid. Diagn. Cytopathol. 2002;27:261–264. © 2002 Wiley‐Liss, Inc.
Diagnostic role of fine‐needle aspiration of pancreatic allograft to detect rejection
Authors: Sariya Dinesh , Kluskens Larry , Assad Lina , Treaba Diana , Reddy Vijaya , Gattuso Paolo
Published: November 2002

The purpose of this study was to assess whether the same principles to evaluate renal transplant by fine‐needle aspiration (FNA) for rejection could be applied to pancreatic allograft. Between 1996–1998, 25 ultrasound‐guided FNAs on 13 patients with pancreatic allograft were performed and ThinPrep® made. The percentage of lymphocytes, lymphoblasts, monocytes, eosinophils, plasma cells, immunoblasts, and macrophages were calculated. Simultaneous peripheral smear was obtained and “total corrected increment” score calculated. Subsequent core biopsy was available in six patients. A total of seven FNAs on three patients were inadequate because of insufficient epithelial cells. No evidence of rejection reported in nine patients was confirmed on biopsy in five patients. One patient reported as suspicious later showed rejection on biopsy. Thus, FNA may be used to monitor the graft status with faster turnaround times. Rejection may be a focal process and FNA may be used for sampling multiple sites. Cytologic diagnosis fairly accurately detects early rejection. Core biopsies are warranted in unsatisfactory specimens and when FNA is suspicious for rejection. Diagn. Cytopathol. 2002;27:266–270. © 2002 Wiley‐Liss, Inc.
Ultrafast Papanicolaou stain and cell‐transfer technique enhance cytologic diagnosis of Hodgkin lymphoma
Authors: Zu Youli , Gangi Maryann D. , Yang Grace C.H.
Published: November 2002

Diagnosis of Hodgkin lymphoma (HL) by fine‐needle aspiration (FNA) is often hampered by aspirated blood that camouflage scattered Hodgkin cells and Reed‐Sternberg (HRS) cells, and the absence of HRS cells in the smears submitted for immunophenotyping. The objective of this study was to develop a simple protocol to overcome these problems. The visibility of HRS cells in Diff‐Quik, traditional, and Ultrafast Papanicolaou (UFP) stains in FNA smears were compared in 73 cases of HL. HRS cells were found to be most visible in UFP because of the hemolysis of aspirated blood and the highlighting of HRS cells by the red‐staining nucleoli. UFP‐stained smears containing HRS cells were subsequently immunophenotyped via the cell‐transfer technique. UFP staining was found to have no deleterious effect on the immunoreactivity of cellular CD15 and CD30 antigens of HRS cells. This simple protocol enhances the cytologic diagnosis of HL, feasible even with a single smear. Diagn. Cytopathol. 2002;27:308–311. © 2002 Wiley‐Liss, Inc.
Subcutaneous myxopapillary ependymoma presenting as a childhood sacrococcygeal tumor: A case report
Authors: Rao I. Satish , Kapila Kusum , Aggarwal Sandeep , Ray Ruma , Gupta Arun Kumar , Verma Kusum
Published: November 2002

Subcutaneous myxopapillary ependymoma in a sacrococcygeal location is an uncommon lesion. We report such a case in a 16‐mo‐old female child, who presented with a sacrococcygeal mass since birth. The cytological picture was that of a malignant small round cell tumor and the diagnosis was missed on cytology, which was retrospectively confirmed on comparison with histology. Although rare, this lesion can be a potential diagnostic pitfall and needs to be distinguished from other malignant tumors occurring at this age and at a similar location, like sacrococcygeal teratoma with immature elements, primitive neuroectodermal tumor (PNET), and PNET with ependymal differentiation. Diagn. Cytopathol. 2002;27:303–307. © 2002 Wiley‐Liss, Inc.
Intrarenal neuroblastoma diagnosed by fine‐needle aspiration: A report of two cases
Authors: Serrano Rosario , Rodríguez‐Peralto José Luis , De Orbe Gabino G. , Melero Carmen , de Agustín Pedro
Published: November 2002

Neuroblastoma is an infrequent tumor of childhood usually located at any site containing sympathetic neural tissue—retroperitoneum and adrenal gland being the most common locations, followed by thoracopulmonary region, mediastinum, head and neck, and pelvis. Two primary renal neuroblastomas were diagnosed in a 6‐yr‐old boy and a 7‐mo‐old boy by computed tomography (CT)‐guided fine‐needle aspiration (FNA) cytology. The smears contained numerous individually scattered small and round cells, with scanty cytoplasm, related to a fibrillary matrix. Scattered larger cells with slightly more cytoplasm were seen among the smaller ones. No tubular or glomeruloid differentiation was noted. Considering the age and cytomorphology, a diagnosis of intrarenal neuroblastoma was made in both cases. An intrarenal mass in a child may occasionally be a neuroblastoma. Our cases demonstrate the usefulness of CT‐guided FNA in diagnosing intrarenal masses in children. Diagn. Cytopathol. 2002;27:294–297. © 2002 Wiley‐Liss, Inc.
Primary squamous cell carcinoma of the endometrium: Case history, pathologic findings, and discussion
Authors: Houissa‐Vuong S. , Catanzano‐Laroudie M. , Baviera E. , Balaton A. , Galet B. , Gedeon I. , Vuong P.N.
Published: November 2002

Primary squamous cell carcinoma of the endometrium (PSCCE) is an exceedingly rare tumor. Rarely are cytological criteria discussed. We report our experience in the cytological diagnosis of a case. A postmenopausal, 64‐yr‐old woman suffered from pyometria. An endometrial Pap smear displayed some malignant squamous cells. Curettage of the cervix and the uterine cavity only recovered some fragments of atypical squamous epithelium whose origin could not be precisely identified. A hysterectomy with bilateral adnexectomy was decided upon. Pathological study evidenced a primary squamous cell carcinoma in the uterine cavity while the cervix was tumor‐free and the lymph nodes were devoid of metastases (pT1, pN0, pM0). The patient died 46 mo PO with multiple pulmonary and renal metastases. The histological feature of PSCCE is identical to that of any tumor of a similar nature, whatever the site, especially the cervix. Confirmation of the primary endometrial nature is only possible on the hysterectomy specimen. Diagn. Cytopathol. 2002;27:291–293. © 2002 Wiley‐Liss, Inc.
Bronchoscopy‐guided transtracheal and transbronchial fine‐needle aspiration biopsy: A 5‐year institutional review of 111 cases
Authors: Xie H. Bill , Cornwell Richard , Grossman Jeffrey E. , Hoerl H. Daniel , Kurtycz Daniel F. I.
Published: November 2002

We reviewed 111 bronchoscopy‐guided transtracheal and transbronchial fine‐needle aspiration (TT/TBNA) specimens from 97 patients to determine the sensitivity and specificity for diagnosing neoplasia compared to surgical biopsy and clinical follow‐up and to determine the optimal number of passes. Fifty were positive for neoplasia, seven were suspicious, one was atypical, 51 were negative, and two were unsatisfactory. Of 57 positive/suspicious cases, 56 were confirmed neoplastic, with one patient lost to follow‐up (specificity with follow‐up: 100%). A positive diagnosis was rendered on the first pass in 29 cases (58%), second in six (12%), third in five (10%), fourth in three (6%), fifth in four (8%), and sixth, ninth, and eleventh passes in one case each (2% each). Twenty‐seven negative cases had confirmed malignancies after their index FNA (sensitivity for neoplasia: 67%). We conclude that TT/TBNA is a highly specific but not always successful diagnostic technique. It appears to be limited by mechanical difficulties that prevent tumor access and cellular uptake in some masses. Little information is gained by procuring more than six samples. Diagn. Cytopathol. 2002;27:276–281. © 2002 Wiley‐Liss, Inc.
Lymphoid and myeloid neoplasms involving cerebrospinal fluid: Comparison of morphologic examination and immunophenotyping by flow cytometry
Authors: Roma Andres A. , Garcia Alejandro , Avagnina Alejandra , Rescia Carla , Elsner Boris
Published: November 2002

We studied 53 samples of cerebrospinal fluid (CSF) by cytologic examination and immunophenotyping by flow cytometry. The samples were taken from 43 patients; 25 had a previous diagnosis of malignant lymphoma/leukemia and the remaining 18 a variety of other diseases involving the central nervous system (CNS). Lymphoma/leukemia was detected in 21 samples: 12 by morphologic examination and immunophenotyping and nine by immunophenotyping alone. There were two cases with a suspicious morphologic examination and negative immunophenotyping in which the final diagnosis were cryptococcal and viral meningitis. In the group of 18 patients, one was diagnosed as a primary malignant lymphoma of the CNS and was positive with cytology and immunophenotyping. The other 17 were negative with both methods and follow‐up showed no evidence of lymphoma/leukemia. This study shows that morphologic examination combined with flow cytometry enhances the detection rate by 75% over morphologic examination alone in CSF samples. Diagn. Cytopathol. 2002;27:271–275. © 2002 Wiley‐Liss, Inc.
Fine‐needle aspiration cytology diagnosis of metastatic gastrointestinal stromal tumor in the liver: A report of three cases
Authors: Padilla Catalina , Saez Amparo , Català Isabel , Vidal August , Garcia Lluis , Tolosa Filomena , Andreu F. Javier , Combalia Neus
Published: November 2002

Gastrointestinal stromal tumor (GIST) is the designation for a major subset of gastrointestinal mesenchymal tumors that histologically, immunocytochemically, and genetically differ from leiomyomas, leiomyosarcomas, and schwannomas. GISTs derive from the interstitial cells of Cajal and, in addition to variable expression of smooth muscle and neural markers, they characteristically express CD34 and CD117. The cytological appearance, including immunocytochemical and mutational analysis of c‐kit gene in primary GIST has been well described. To our knowledge, only two cases of metastatic GIST diagnosed by fine‐needle aspiration (FNA) have been reported. We illustrate three cases of metastatic GIST in the liver. Two cases had no prior history of gastrointestinal tumor and the third case had a 4‐yr previous history of duodenal tumor. Consistent immunocytochemistry and ultrastructual studies supported the diagnosis of GIST. We emphasize that in the appropriate clinical and radiological setting, a confident diagnosis of GIST can be established by FNA of metastatic lesions. Diagn. Cytopathol. 2002;27:298–302. © 2002 Wiley‐Liss, Inc.
Large B‐cell lymphomas: Fine‐needle aspiration plays an important role in initial diagnosis of cases which are falsely negative by flow cytometry
Authors: Verstovsek Gordana , Chakraborty Subhendu , Ramzy Ibrahim , Jorgensen Jeffrey L.
Published: November 2002

Large B‐cell lymphomas (LBCLs) have significant false‐negative results when immunophenotyped by flow cytometry (FC). To clarify the role fine‐needle aspiration (FNA) in reducing this false‐negative rate, 28 cases ultimately diagnosed as LBCL that had FNA as part of the workup and a negative FC were identified. We examined their clinical and cytologic features, in comparison with cases of LBCL with FNAs that were positive by FC. In 24/28 FC‐negative cases (86%) a cytologic diagnosis of suspicious or positive for malignancy was rendered. We conclude that cytologic analysis is more sensitive than FC in the diagnosis of malignancy in FNA of LBCL, particularly in aspirates with low cellularity and/or low viability. Examination of cytospin preparations of the actual material analyzed by FC may provide an indication that an FC result is falsely negative. It is important to recognize the potential of false‐negativity by FC of LBCLs when interpreting FNAs with features suggesting lymphoma. Diagn. Cytopathol. 2002;27:282–285. © 2002 Wiley‐Liss, Inc.
PREPmate automated processor: Comparison of automated and manual methods of liquid‐based gynecologic sample preparation
Authors: Rowe Leslie R. , Marshall C. Jay , Bentz Joel S.
Published: November 2002

The development of procedures for fully automated processing of liquid‐based gynecologic samples has been the focus of considerable interest to the cytology laboratory. Liquid‐based collection and processing technology has been shown to improve sample adequacy, resulting in an overall improvement in quality of sample preparations. PREPmate™, an accessory to the PrepStain™ slide processor, automates the initial enrichment process of mixing and dispensing the specimen over a density gradient. This report describes a study evaluating cellularity and diagnostic reproducibility in SurePath™ samples processed using the PREPmate™ accessory compared to samples processed using a manual technique. Samples processed using the PREPmate™ accessory contained 8.3% more squamous cells. Exact diagnostic reproducibility between preparation types was 83.3%; when considering negative vs. abnormal (ASCUS+), in adequate samples, reproducibility was 100%. Diagn. Cytopathol. 2002;27:312–315. © 2002 Wiley‐Liss, Inc.
Cytomorphologic features of fine‐needle aspiration of metastatic and recurrent melanoma
Authors: Saqi Anjali , McGrath Cindy M. , Skovronsky Daniel , Yu Gordon H.
Published: November 2002

Melanoma is an aggressive malignancy with a growing prevalence. Although early detection and excision offer a potential cure, recurrences and metastases are not uncommon. Fine‐needle aspiration (FNA) can play a vital role in their detection as a relatively noninvasive, rapid, and economical alternative for tracking disease evolution. Prior clinical history and classic cytological features of melanoma (loosely cohesive smear pattern and single cells with large nuclei, prominent nucleoli, and melanin pigment) aid in cytological diagnoses. However, not all melanomas contain melanin pigment or characteristic cytologic features. We examined a large series of melanoma cases to determine the incidence of melanin pigment, the most common cell morphology, and the presence or absence of apoptosis/necrosis associated with this highly aggressive neoplasm. Diagn. Cytopathol. 2002;27:286–290. © 2002 Wiley‐Liss, Inc.
Pineal‐specific expression of green fluorescent protein under the control of the serotonin‐N‐acetyltransferase gene regulatory regions in transgenic zebrafish
Authors: Gothilf Yoav , Toyama Reiko , Coon Steven L. , Du Shao‐Jun , Dawid Igor B. , Klein David C.
Published: November 2002

Zebrafish serotonin‐N‐acetyltransferase‐2 (zfAANAT‐2) mRNA is exclusively expressed in the pineal gland (epiphysis) at the embryonic stage. Here, we have initiated an effort to study the mechanisms underlying tissue‐specific expression of this gene. DNA constructs were prepared in which green fluorescent protein (GFP) is driven by regulatory regions of the zfAANAT‐2 gene. In vivo transient expression analysis in zebrafish embryos indicated that in addition to the 5′‐flanking region, a regulatory sequence in the 3′‐flanking region is required for pineal‐specific expression. This finding led to an effort to produce transgenic lines expressing GFP under the control of the 5′ and 3′ regulatory regions of the zfAANAT‐2 gene. Embryos transiently expressing GFP were raised to maturity and tested for germ cell transmission of the transgene. Three transgenic lines were produced in which GFP fluorescence in the pineal was detected starting 1 to 2 days after fertilization. One line was crossed with mindbomb and floating head mutants that cause abnormal development of the pineal and an elevation or reduction of zfAANAT‐2 mRNA levels, respectively. Homozygous mutant transgenic embryos exhibited similar effects on GFP expression in the pineal gland. These observations indicate that the transgenic lines described here will be useful in studying the development of the pineal gland and the mechanisms that determine pineal‐specific gene expression in the zebrafish. Published 2002 Wiley‐Liss, Inc.
Different patterns of anti‐Müllerian hormone expression, as related to DMRT1, SF‐1, WT1, GATA‐4, Wnt‐4, and Lhx9 expression, in the chick differentiating gonads
Authors: Oréal Emmanuelle , Mazaud Séverine , Picard Jean‐Yves , Magre Solange , Carré‐Eusèbe Danièle
Published: November 2002

In mammals, anti‐Müllerian hormone (AMH) is produced by Sertoli cells from the onset of testicular differentiation and by granulosa cells after birth. In birds, AMH starts to be expressed in indifferent gonads of both sexes at a similar level and is later up‐regulated in males. We previously demonstrated that, unlike in mammals, the onset of AMH expression occurs in chick embryo in the absence of SOX9. We looked for potential factors that might be involved in regulating AMH expression at different stages of chick gonad differentiation by comparing its expression pattern in embryos and young chicken with that of DMRT1, SF‐1, WT1, GATA‐4, Wnt‐4, and Lhx9, by in situ hybridization. The results allowed us to distinguish different phases. (1) In indifferent gonads of both sexes, AMH is expressed in dispersed medullar cells. SF‐1, WT1, GATA‐4, Wnt‐4, and DMRT1 are transcribed in the same region of the gonads, but none of these factors has an expression strictly coincident with that of AMH. Lhx9 is present only in the cortical area. (2) After this period, AMH is up‐regulated in male gonads. The up‐regulation is concomitant with the beginning of SOX9 expression and a sex dimorphic level of DMRT1 transcripts. It is followed by the aggregation of the AMH‐positive cells (Sertoli cells) into testicular cords in which AMH is coexpressed with DMRT1, SF‐1, WT1, GATA‐4, and SOX9. (3) In the females, the low level of dispersed medullar AMH expression is conserved. With development of the cortex in the left ovary, cells expressing AMH accumulate in the juxtacortical part of the medulla, whereas they remain dispersed in the right ovary. At this stage, AMH expression is not strictly correlated with any of the studied factors. (4) After hatching, the organization of left ovarian cortex is characterized by the formation of follicles. Follicular cells express AMH in conjunction with SF‐1, WT1, and GATA‐4 and in the absence of SOX9, as in mammals. In addition, they express Lhx9 and Wnt‐4, the latter being also found in the oocytes. (5) Moreover, unlike in mammals, the chicken ovary retains a dispersed AMH expression in cortical interstitial cells between the follicles, with no obvious correlation with any of the factors studied. Thus, the dispersed type of AMH expression in indifferent and female gonads appears to be bird‐specific and not controlled by the same factors as testicular or follicular AMH transcription. © 2002 Wiley‐Liss, Inc.
Isolation and developmental expression analysis of Tbx22, the mouse homolog of the human X‐linked cleft palate gene
Authors: Bush Jeffrey O. , Lan Yu , Maltby Kathleen M. , Jiang Rulang
Published: November 2002

Mutations in the TBX22 gene have been identified recently in patients with the X‐linked cleft palate and ankyloglossia syndrome, suggesting that the TBX22 transcription factor plays an important role in palate development. However, because ankyloglossia has been reported in the majority of patients with TBX22 mutations, it has been speculated that the cleft palate phenotype is secondary to defective fetal tongue movement. To understand the role of TBX22 in disease pathogenesis and in normal development, it is necessary to carry out a detailed temporal and spatial gene expression analysis. We report here the isolation and developmental expression analysis of the mouse homolog Tbx22. The mouse Tbx22 gene encodes a putative protein of 517 amino acid residues, which shares 72% overall amino acid sequence identity with the human TBX22 protein. By using interspecific backcross analysis, we have localized the Tbx22 gene to mouse chromosome X, in a region syntenic to human chromosome Xq21, where the TBX22 gene resides, indicating that Tbx22 is the ortholog of human TBX22. Our in situ hybridization analysis shows that Tbx22 is expressed in a temporally and spatially highly restricted pattern during mouse palate and tongue development. Together with the mutant phenotypes in human patients, our data indicate a primary role for Tbx22 in both palate and tongue development. © 2002 Wiley‐Liss, Inc.
Anteroposterior axis formation in Xenopus limb bud recombinants: A model of pattern formation during limb regeneration
Authors: Yokoyama Hitoshi , Tamura Koji , Ide Hiroyuki
Published: November 2002

We previously showed that recombinant limb buds with dissociated and reaggregated mesenchyme develop more than 30 digits in Xenopus laevis, which exhibits different capacities for limb regeneration at different developmental stages (Yokoyama et al. [1998] Dev Biol 196:1–10). Cell–cell contact among anterior‐ and posterior‐derived mesenchymal cells is required for anteroposterior (AP) axis formation of recombinant limbs in an intercalary manner. However, whether one‐way induction from posterior cells to anterior cells as proposed by the polarizing zone model or interactions between anterior and posterior cells evoke the AP axis formation in recombinant limbs remains unclear. In this study, we found, by a combination of X‐ray irradiation and a recombinant limb technique, that not one‐way induction but interactions between anterior and posterior cells accompanied by cell contribution are indispensable for AP axis formation in recombinant limbs. Shh was expressed in posterior‐derived not anterior‐derived cells. We propose that the recombinant limb is an excellent model for examining the axis formation mechanism in regenerating limbs because, as in recombinant limbs, cell–cell contact among cells derived from different positions of an amputation plane occurs in the blastema of regenerating limbs. © 2002 Wiley‐Liss, Inc.
Expression of oncostatin M in hematopoietic organs
Authors: Tamura Shinobu , Morikawa Yoshihiro , Miyajima Atsushi , Senba Emiko
Published: November 2002

Murine oncostatin M (OSM), a member of the interleukin‐6 (IL‐6) ‐related cytokine subfamily, stimulates definitive hematopoiesis and liver development. The OSM gene was cloned as a cytokine‐inducible early response gene in some hematopoietic cell lines. In this study, we performed in situ hybridization to examine the tissue distribution of cells expressing OSM mRNA in the developing and the adult mice. Its gene expression was seen in hematopoietic cells of developing liver from 11.5 days postcoitum (dpc), and persisted to the neonates. From 17.5 dpc, OSM mRNA‐positive cells were found in other hematopoietic organs, including bone marrow, thymus, and spleen. The highest levels of gene expression were observed in the adult bone marrow. Most OSM‐expressing cells expressed IL‐5 receptor α subunit, a marker for eosinophil lineage. In addition, some positive cells expressed neutrophil elastase, which was used as a polymorphonuclear neutrophil (PMN) marker. After birth, OSM mRNA was expressed in tissue eosinophils in nonhematopoietic organs, including small intestine, lung, and skin. Our data revealed that eosinophil progenitors and eosinophils as well as PMNs are also an important cellular source of OSM in mice. © 2002 Wiley‐Liss, Inc.
Expression patterns of Wnts, Frizzleds, sFRPs, and misexpression in transgenic mice suggesting a role for Wnts in pancreas and foregut pattern formation
Authors: Heller R. Scott , Dichmann Darwin S. , Jensen Jan , Miller Chris , Wong Gordon , Madsen Ole D. , Serup Palle
Published: November 2002

It is well established that gut and pancreas development depend on epithelial‐mesenchymal interactions. We show here that several Wnt, Frizzled, and secreted frizzled‐related protein (sFRP) encoding mRNAs are present during mouse pancreatic morphogenesis. Wnt5a and 7b mRNA is broadly expressed in foregut mesenchyme starting around embryonic day 10 in mice. Other members expressed are Wnt2b, Wnt5b, and Wnt11. In addition, genes for the Wnt receptors, Frizzled2, 3, 4, 5, 6, 7, 8, and 9 are expressed. To understand potential Wnt functions in pancreas and foregut development in vivo, we analyzed transgenic F0 mouse fetuses expressing Wnt1 and 5a cDNAs under control of the PDX‐1 gene promoter. In PDX‐Wnt1 fetuses, the foregut region normally comprising the proximal duodenum instead resembles a posterior extension of the stomach, often associated with complete pancreatic and splenic agenesis. Furthermore, the boundary between expression domains of gastric and duodenal markers is shifted in a posterior direction. In PDX‐Wnt5a fetuses, several structures derived from the proximal foregut are reduced in size, including the pancreas, spleen, and stomach, without any apparent shift in the stomach to duodenum transition. In these fetuses, overall pancreatic morphology is changed and the pancreatic epithelium is dense and compact, consistent with Wnt5A effects on cell movements and/or attachment. Taken together, these results suggest that Wnt genes participate in epithelial‐mesenchymal signaling and may specify region identity in the anterior foregut. © 2002 Wiley‐Liss, Inc.
Role of VEGF family members and receptors in coronary vessel formation
Authors: Tomanek Robert J. , Holifield Jennifer S. , Reiter Rebecca S. , Sandra Alexander , Lin Jim J.‐C.
Published: November 2002

The specific roles of vascular endothelial growth factor (VEGF) family members and their receptors (VEGFRs) in coronary vessel formation were studied. By using the quail heart explant model, we found that neutralizing antibodies to VEGF‐B or VEGF‐C inhibited tube formation on the collagen gel more than anti–VEGF‐A. Soluble VEGFR‐1, a receptor for VEGF‐A and ‐B, inhibited tube formation by 87%, a finding consistent with that of VEGF‐B inhibition. In contrast, addition of soluble VEGFR‐2, a receptor for VEGF family members A, C, D, and E, inhibited tube formation by only 43%. Acidic FGF‐induced tube formation dependency on VEGF was demonstrated by the attenuating effect of a soluble VEGFR‐1 and ‐2 chimera. The localization of VEGF R‐2 and R‐3 was demonstrated by in situ hybridization of serial sections, which documented marked accumulations of transcripts for both receptors at the base of the truncus arteriosus coinciding with the temporal and spatial formation of the coronary arteries by means of ingrowth of capillary plexuses. This finding suggests that both VEGFR‐2 and R‐3 may play a role in the formation of the coronary artery roots. In summary, these experiments document a role for multiple members of the VEGF family and their receptors in formation of the coronary vascular bed. © 2002 Wiley‐Liss, Inc.
PLEXIN‐D1, a novel plexin family member, is expressed in vascular endothelium and the central nervous system during mouse embryogenesis
Authors: Van Der Zwaag Bert , Hellemons Anita J.C.G.M. , Leenders William P.J. , Burbach J. Peter H. , Brunner Han G. , Padberg George W. , Van Bokhoven Hans
Published: November 2002

The genetic defect in Möbius syndrome 2 (MBS2, MIM 601471), a dominantly inherited disorder characterised by paralysis of the facial nerve, is situated at chromosome 3q21‐q22. We characterised the cDNA and predicted protein, and examined the expression pattern during mouse embryogenesis of a positional candidate gene, PLEXIN‐D1 (PLXND1). The cDNA for PLXND1 is 7095 base pairs in length, coding for a predicted protein of 1925 amino acids. The protein features all known domains of plexin family members, with the exception of the third Met‐related sequence. Northern analysis revealed a very low expression of PLXND1 in adult mouse and adult human tissues. To investigate the expression of PlxnD1 during embryogenesis, RNA in situ hybridisation was performed on mouse embryos from various stages. This investigation revealed expression of PlxnD1 in cells from the central nervous system (CNS) and in vascular endothelium. Early expression in the CNS is located in the ganglia, cortical plate of the cortex, and striatum. At later embryologic stages, neural expression was also seen in the external granular layer of the cerebellum and several nerve nuclei. The expression in the vascular system resides solely in the endothelial cells of developing blood vessels. Based on our results, we suggest that this expression of a member of the plexin family in vascular endothelium could point toward a role in embryonic vasculogenesis. © 2002 Wiley‐Liss, Inc.
Multiple mechanisms of perichondrial regulation of cartilage growth
Authors: Di Nino Dana L. , Crochiere Marsha L. , Linsenmayer Thomas F.
Published: November 2002

We previously observed that the perichondrium (PC) and the periosteum (PO) negatively regulate endochondral cartilage growth through secreted factors. Conditioned medium from cultures of PC and PO cells when mixed (PC/PO‐conditioned medium) and tested on organ cultures of embryonic chicken tibiotarsi from which the PC and PO have been removed (PC/PO‐free cultures) effect negative regulation of growth. Of potential importance, this regulation compensates precisely for removal of the PC and PO, thus mimicking the regulation effected by these tissues in vivo. We have now examined whether two known negative regulators of cartilage growth (retinoic acid [RA] and transforming growth factor‐β1 [TGF‐β1]) act in a manner consistent with this PC/PO‐mediated regulation. The results suggest that RA and TGF‐β1, per se, are not the regulators in the PC/PO‐conditioned medium. Instead, they show that these two factors each act in regulating cartilage growth through an additional, previously undescribed, negative regulatory mechanism(s) involving the perichondrium. When cultures of perichondrial cells (but not periosteal cells) are treated with either agent, they secrete secondary regulatory factors into their conditioned medium, the action of which is to effect precise negative regulation of cartilage growth when tested on the PC/PO‐free organ cultures. This negative regulation through the perichondrium is the only activity detected with TGF‐β1. Whereas, RA shows additional regulation on the cartilage itself. However, this regulation by RA is not “precise” in that it produces abnormally shortened cartilages. Overall, the precise regulation of cartilage growth effected by the action of the perichondrial‐derived factor(s) elicited from the perichondrial cells by treatment with either RA or TGF‐β1, when combined with our previous results showing similar—yet clearly different—“precise” regulation by the PC/PO‐conditioned medium suggests the existence of multiple mechanisms involving the perichondrium, possibly interrelated or redundant, to ensure the proper growth of endochondral skeletal elements. © 2002 Wiley‐Liss, Inc.
PI‐3 kinase activity is required for epithelial‐mesenchymal transformation during palate fusion
Authors: Kang Pei , Svoboda Kathy K.H.
Published: November 2002

Epithelial‐mesenchymal transformation (EMT) is the primary mechanism for the disappearance of medial edge epithelia (MEE) during palate fusion. This phenotype transition is highly regulated by growth factors, extracellular matrix, cell surface receptors, and a variety of intracellular signaling. Phosphatidylinositol‐3 (PI‐3) kinase regulates cytoskeleton reorganization, cell migration, and transforming growth factor (TGF) β–regulated EMT. Therefore, we investigated the role of PI‐3 kinase in EMT during palatal fusion in vitro. Palatal shelves from embryonic (E) 13.5 day mouse embryos were collected and cultured for up to 72 hr. A specific PI‐3 kinase inhibitor, LY294002, was added to the medium at concentrations of 100 ηM, 1 μM, and 10 μM. The fate of midline epithelia was traced by carboxyfluorescence labeling and analyzed by confocal microscopy. Harvested tissues were also processed for immunohistochemical analysis of a specific marker for basal lamina (laminin). Palatal fusion stages were scored on a scale of 1 to 5, with 1 equal to complete nonfusion and 5 equal to complete fusion. The mean fusion score (MFS) was calculated for each treatment group. Palatal shelves fused after 72 hr of culture in control and 100 ηM LY294002 inhibitor‐treated groups, with MFS of 4.67 and 4.5, respectively. Laminin was absent in the midline and epithelia transformed into mesenchyme. However, when cultured palates were treated with 1 and 10 μM LY294002, MEE persisted in the midline and the basal lamina remained intact after 72 hr. The MFS was significantly less in the 1 and 10 μM LY294002‐treated tissues at 2.08 and 1.33, respectively. Our results demonstrate that EMT during palatal fusion in vitro is dependent on PI‐3 kinase activity. © 2002 Wiley‐Liss, Inc.
VEGF signaling is required for the assembly but not the maintenance of embryonic blood vessels
Authors: Argraves W. Scott , Larue Amanda C. , Fleming Paul A. , Drake Christopher J.
Published: November 2002

Here we investigated the importance of vascular endothelial growth factor (VEGF) signaling to the de novo formation of embryonic blood vessels, vasculogenesis, as opposed to the maintenance of blood vessels. We found that antagonizing the activity of the VEGF signaling pathway by using soluble VEGF receptor 1 (sFlt1) or VEGF antibodies inhibited vasculogenesis that occurs in embryos and in cultures of 7.5 days postcoitus prevascular mesoderm. Antagonist treatment resulted in the formation of clusters of endothelial cells not normally observed during vasculogenesis. In contrast, when embryos with established vasculatures or cultures of vascularized mesoderm were treated with sFlt1 or VEGF antibodies, no discernible alterations to the preexisting blood vessels were observed. These observations indicate that, although VEGF signaling is required to promote the mesenchymal to epithelial transition by which angioblasts assemble into nascent endothelial tubes, it is not required by endothelial cells to maintain their organization as an endothelium. © 2002 Wiley‐Liss, Inc.