bluuebunny/crossref_metadata_2025 huggingface dataset:
Mycobacterial Isolations in Captive Elephants in the United States
Authors: PAYEUR JANET B. , JARNAGIN J. L. , MARQUARDT J. G. , WHIPPLE D. L.
Published: July 2009

Abstract: Interest in tuberculosis in elephants has been increasing over the past several years in the United States. Several techniques have been used to diagnose mammalian tuberculosis. Currently, the test considered most reliable for diagnosis of TB in elephants is based on the culture of respiratory secretions obtained by trunk washes.
Tick‐Borne Diseases (TBDs) of Dairy Cows in a Mediterranean Environment
Authors: TASSI P. , CARELLI G. , CECI L.
Published: July 2009

Abstract: A longitudinal study of tick‐borne diseases (TBDs) in Southern Italy was carried out by monitoring two dairy farms (A and B) located in the Apulia Region. On each farm ten calves and ten heifers were observed monthly from May 1999 to February 2001 for clinical signs and blood parameters; antibodies against Babesia bigemina and Anaplasma marginale using an ELISA test were also monitored for the first eight months of the study. Totals of 28 and 14 cases of TBDs were observed in the complete herds of Farms A and B, respectively. Timing of disease appearance, categories of animals affected and changes in blood parameters are discussed.
Pathology of Avian Pox in Wild Red‐Legged Partridges (Alectoris rufa) in Spain
Authors: GORTÁZAR C. , MILLÁN J. , HÖFLE U. , BUENESTADO F. J. , VILLAFUERTE R. , KALETA E. F.
Published: July 2009

Abstract: The diagnosis and pathology of an avian pox outbreak in free‐living red‐legged partridges in Cádiz, Southern Spain, is described. Diagnosis of the disease was based on histopathology, ultrastructural examination of, and virus isolation from lesions of necropsied animals. Lesions were present mainly in juvenile partridges (41%), and were observed primarily on the dorsal part of the digits or on the hock joint. The lesions ranged from small wartlike nodules to large tumor‐like lesions. The presence of acute lesions of any grade as opposed to absence of lesions or healed lesions adversely affected body condition of the partridges (P < .01). Further investigations on the epidemiology of the disease and on the relation of the isolated strains to other avian poxviruses are under way.
New Advances in the Biochemical Diagnosis of Pheochromocytoma
Authors: LENDERS JACQUES W.M. , PACAK KAREL , EISENHOFER GRAEME
Published: July 2009

Abstract: Pheochromocytomas are dangerous tumors that, although a rare cause of hypertension, require consideration among large numbers of patients. The resulting low prevalence of the tumor among tested populations and the inadequacies of commonly used biochemical tests make excluding or confirming the tumor an often difficult and time‐consuming task. Recognition that catecholamines are metabolized to free metanephrines within pheochromocytoma tumor cells, and that this process is independent of catecholamine release, provides a rationale for use of these metabolites in the biochemical diagnosis of pheochromocytoma. Here we briefly review the history of biochemical diagnosis of pheochromocytoma in relation to recent data about the diagnostic utility of plasma free metanephrines for detection of these tumors. Measurements of urinary or plasma catecholamines have reasonable sensitivity for detection of most pheochromocytomas, particularly those in patients with sustained hypertension. False‐negative test results can, however, occur in asymptomatic patients tested because of an adrenal incidentaloma or a familial predisposition for pheochromocytoma, or when sampling is carried out between episodes of paroxysmal hypertension. Measurements of urinary total metanephrines or vanillylmandelic acid are less reliable and are of little value as initial screening tests. In contrast, measurements of plasma concentrations or free metanephrines or 24‐hour urinary outputs of fractionated normetanephrine and metanephrine almost always reveal the tumor. Although, both tests have similarly high sensitivity, the relatively low specificity of urinary fractionated metanephrines means that pheochromocytomas can be more efficiently excluded or confirmed using measurements of plasma free metanephrines.
New Genetic Insights in Familial Hyperaldosteronism
Authors: JACKSON RICHARD V. , LAFFERTY ANTHONY , TORPY DAVID J. , STRATAKIS CONSTANTINE
Published: July 2009

Abstract: Aldosterone, the major circulating mineralocorticoid, particiates in blood volume and serum potassium homeostasis. Primary aldosteronism is a disorder characterized by hypertension and, in more severe form, hypokalemia, due to autonomous aldosterone secretion from the adrenocortical zona glomerulosa. Improved screening techniques, particularly application of the plasma aldosterone: plasma renin activity ratio, has led to renewed interest in Conn's original proposal that primary aldosteronism may be the cause of increased blood pressure in about 10% of adults with hypertension. Glucocorticoid‐remediable aldosteronism (GRA) was the first described familial form of hyperaldosteronism. The disorder is characterized by aldosterone secretory function regulated chronically by ACTH. Hence, aldosterone hypersecretion can be chronically suppressed by exogenous glucocorticoids such as dexamethasone in physiologic‐range doses. This autosomal dominant disorder has been shown to be caused by a hybrid gene mutation formed by a cross‐over of genetic material between the ACTH‐responsive regulatory portion of the 11b‐hydroxylase (CYP11B1) gene and the coding region of the aldosterone synthase (CYP11B2) gene. Familial hyperaldosteronism type II (FH‐II), so named to distinguish the disorder from GRA or familial hyperaldosteronism type I (FH‐I), is characterized by inheritance consistent with an autosomal dominant pattern of autonomous aldosterone hypersecretion which is not suppressible by dexamethasone. Linkage analysis in a single large kindred, and direct mutation screening, has shown that this disorder is unrelated to mutations in the genes for aldosterone synthase or the angiotensin II receptor. A recent genome‐wide search has identified a genetic linkage between FH‐II in this single large kindred and polymorphic gene markers on chromosome 7 in a region that corresponds to cytogenetic band 7p22. This is the first identified locus for FH‐II. Several possible candidate genes have been localized to the 7p22 region. The precise genetic cause of FH‐II remains to be elucidated.
Familial/Sporadic Glucocorticoid Resistance Syndrome and Hypertension
Authors: KINO TOMOSHIGE , VOTTERO ALESSANDRA , CHARMANDARI EVANGELIA , CHROUSOS GEORGE P.
Published: July 2009

Abstract: Glucocorticoids regulate diverse functions important for the maintenance of central nervous system, cardiovascular, metabolic, and immune homeostasis. The actions of these hormones are mediated by the specific intracellular glucocorticoid receptors (GRs). Pathologic conditions associated with changes of tissue sensitivity to these hormones have been described. The syndrome of familial/sporadic glucocorticoid resistance is characterized by hypercortisolism without Cushing syndrome stigmata. Many of the patients present with hypertension, with or without hypokalemic alkalosis, as a result of elevated concentrations of cortisol and other salt‐retaining steroids. The molecular defects of 4 kindreds and one sporadic case have been elucidated as inactivating mutations in the ligand‐binding domain of the GR. In two patients in whom the GR was mutated at amino acid isoleucine 559 to aspartic acid (GRαI559N) and isoleucine 747 to methionine (GRαI747M), respectively, glucocorticoid resistance developed at the heterozygous state, with transdominant negative activity of each of the mutant receptors upon the wild‐type protein. Retention of the wild‐type receptor in the cytoplasm by the mutant receptor was found in the former, while inappropriate accumulation of p160‐type coactivators on the promoter region of glucocorticoid‐responsive genes, because of a defective interaction between the AF2 region of the mutant receptor and the LXXLL motif of the coactivators, was determined in the latter. These results suggest that the pathologic mechanisms of glucocorticoid resistance is quite broad, and this is reflected in the wide variability of the clinical picture in patients with the syndrome.
Diagnostic Localization of Pheochromocytoma
Authors: PACAK KAREL , EISENHOFER GRAEME , CARRASQUILLO JORGE A. , CHEN CLARA C. , WHATLEY MILLIE , GOLDSTEIN DAVID S.
Published: July 2009

Abstract: Pheochromocytoma is a rare but clinically important tumor of catecholamine‐secreting chromaffin cells. This tumor constitutes a surgically curable cause of hypertension. Therefore, correct localization of pheochromocytoma is essential for effective management of this tumor. Several conventional and nuclear imaging modalities are currently available to localize pheochromocytoma. Computed tomography (CT) and magnetic resonance imaging (MRI) have good sensitivity but poor specificity for detecting pheochromocytoma, and nuclear imaging approaches such as 131I‐metaiodobenzylguanidine scintigraphy or [111In]‐DTPA‐D‐Phe‐pentetreotide (Octreoscan) have limited sensitivity. However, specificity of 131I‐metaiodobenzylguanidine scintigraphy is very good and this means of imaging provides a method for confirming that a tumor is a pheochromocytoma and rules out metastatic disease. Recently, we introduced a new imaging method, 6‐[18F]fluorodopamine positron emission tomography, that can be used successfully for the detection of solitary and metastatic pheochromocytomas. Our preliminary data suggest that this method is superior to other nuclear imaging methods including metaiodobenzylguanidine and octreotide scintigraphy. In this report we provide an update regarding nuclear imaging of primary and metastatic pheochromocytoma, particularly using 6‐[18F]fluorodopamine positron emission tomographic scanning.
Genomic Medicine
Authors: ALESCI SALVATORE , CHROUSOS GEORGE P. , PACAK KAREL
Published: July 2009

Abstract: Recent improvements in defining the molecular basis of disease have encouraged scientists worldwide to develop new therapeutic strategies based on engineered genes and cells. Genomic medicine has the potential to revolutionize diagnosis and therapy of a variety of human diseases, including endocrine disorders. Hypertension is the presenting feature of some of these disorders, such as congenital adrenal diseases, and adrenal and pituitary tumors. Preclinical data indicate that gene transfer to both the adrenal gland and the pituitary is not only feasible but also quite efficient. Research in this field is only in its infancy, but with the ever‐increasing advances in DNA technologies, genomic therapies for endocrine hypertension may become available within the next few decades.
Hypoxia Activates Multiple Transcriptional Pathways in Mouse Pheochromocytoma Cells
Authors: EVINGER MARIAN J. , CIKOS STEFAN , NWAFOR‐ANENE VICTORIA , POWERS JAMES F. , TISCHLER ARTHUR S.
Published: July 2009

Abstract:Mouse pheochromocytoma cells (MPCs) provide an excellent model system for investigating the effects of hypoxia on catecholamine enzyme genes and on transcription factors mediating stress responses. RT‐PCR detects rapid, transient increases in PNMT mRNA in hypoxic MPC 712 cells. Additionally, elevation of mRNAs encoding transcription factors hypoxia inducible factor 1 (HIF‐1) α subunit and Egr‐1 are evident within 60 min incubation in anoxia. Therefore, hypoxia elicits rapid transcriptional responses in numerous genes expressed by chromaffin cells.
Catecholamine Metabolism: An Update on Key Biosynthetic Enzymes and Vesicular Monoamine Transporters
Authors: FLATMARK TORGEIR , ALMÅS BJØRG , ZIEGLER MICHAEL G.
Published: July 2009

Abstract: At the meeting, new interesting information was presented on the complex regulation of catecholamine (CA) metabolism in different catecholaminergic neuroendocrine cells. In this review we focus on the rate‐limiting enzymes in CA biosynthesis, including (1) structure‐function relationships, (2) transcriptional and posttranslational regulation, and (3) disease‐associated mutant forms. Moreover, some recent studies on the structure and function of the vesicular monoamine transporters are discussed.
Enhancement of Neuronal Nicotinic Receptor Activity of Rat Chromaffin Cells by a Novel Class of Peptides
Authors: NISTRI ANDREA , DI ANGELANTONIO SILVIA
Published: July 2009

Abstract: The N‐terminal 1‐7 fragment of the neuropeptide CGRP inhibits neuronal nicotinic acetylcholine receptors (nAChRs) of rat chromaffin cells. To identify the structural motif responsible for this action, we investigated the effects of shorter CGRP fragments on patch‐clamped rat chromaffin cells in culture. CGRP1‐6 evoked no direct change in baseline current or input conductance, but it strongly potentiated inward currents induced by very fast, nondesensitizing applications of nicotine. Potentiation was use independent and present even when coapplied with nicotine. The action of CGRP1‐6 was voltage independent and agonist independent. Because equimolar concentrations of CGRP1‐6 and CGRP1‐7 left nicotine‐induced submaximal currents unchanged, these peptides presumably acted via a similar site through which they generated opposite effects. This observation also suggests that a single amino acid deletion could transform a peptide antagonist into a potentiating one. Deleting one amino acid from the COO− end of the CGRP1‐6 sequence yielded CGRP1‐5, which retained smaller potentiating activity. Even the CGRP1‐4 fragment possessed slight potentiation, which was lost with CGRP1‐3. CGRP1‐6 preferentially potentiated small over large responses to nicotine. One possibility is that CGRP1‐6 interacted with nAChRs like an allosteric modulator (e.g., physostigmine). Coapplication of enhancing concentrations of physostigmine and CGRP1‐6 led to linear summation of the individual effects, while CGRP1‐6 could partly reverse the depression by a large concentration of physostigmine. These data indicate functionally distinct sites of action for CGRP1‐6 and physostigmine. Potentiation of nicotinic receptors by CGRP1‐6 and its derivatives suggests them to be a new class of molecules enhancing activity mediated by nAChRs.
Calcium Entry, Calcium Redistribution, and Exocytosis
Authors: CUCHILLO‐IBÁÑEZ INMACULADA , ALBILLOS ALMUDENA , ALDEA MARCOS , ARROYO GLORIA , FUENTEALBA JORGE , GARCÍA ANTONIO G.
Published: July 2009

Abstract: At a given cytosolic domain of a chromaffin cell, the rate and amplitude of the Ca2+ concentration, [Ca2+]c, depend on at least three efficient regulatory mechanisms: (1) the plasmalemmal Ca2+ channels; (2) the endoplasmic reticulum (ER); and (3) the mitochondria. High‐voltage activated Ca2+ channels of the L, N, P/Q, and R subtypes are expressed with different densities in various mammalian species; they are regulated by G proteins coupled to purinergic and opiate receptors, as well as by voltage and the local changes of [Ca2+]c. Targeted aequorin and confocal microscopy show that Ca2+ entry through Ca2+ channels can refill the ER to near millimolar concentrations and causes the release of ER Ca2+ (CICR). We have also seen that, depending on its degree of filling, the ER may act as a sink or source of Ca2+ that modulates the release of catecholamine. Targeted aequorins with different Ca2+ affinities show that mitochondria undergo surprisingly rapid millimolar Ca2+ transients ([Ca2+]M) upon stimulation of chromaffin cells with ACh, high K+, or caffeine. Physiological stimuli generate [Ca2+]c microdomains at these functional complexes in which the local subplasmalemmal [Ca2+]c rises abruptly from 0.1 μM to about 50 μM. This triggers CICR, mitochondrial Ca2+ uptake, and exocytosis in nearby secretory active sites. That this is true is shown by the observation that protonophores abolish mitochondrial Ca2+ uptake and drastically increase catecholamine release by 3‐ to 5‐fold. This increase is likely due to acceleration of vesicle transport from a reserve pool to a ready‐release vesicle pool; such transport might be controlled by Ca2+ redistribution to the cytoskeleton, through CICR and/or mitochondrial Ca2+ release.
Calcium Transport Proteins in Active Secretory Zones
Authors: SCHNEIDER A. S. , MAH S. J. , FARHADI M. , GRINDI E. , DAVIS K. H.
Published: July 2009

Abstract: We have found that Na—Ca exchange influences Ca2+ efflux, signal decay, and the rate of secretion in chromaffin cells. We now report the presence of two distinct splicing variant isoforms of Na—Ca exchange proteins in bovine chromaffin cells and their transport properties in chromaffin granules and plasma membrane vesicles.
Pharmacological Regulation of the Late Steps of Exocytosis
Authors: BORGES RICARDO , MACHADO J. DAVID , BETANCOR GEMA , CAMACHO MARCIAL
Published: July 2009

Abstract:We used amperometry to analyze the role of several second messengers and drugs in the exocytotic kinetics of bovine chromaffin cells. Activation of PKG produces a slowing down of exocytosis, which is not generally accompanied by changes in the net granule content of catecholamines. These effects are also observed after mild PKA activation. However, strong PKA stimulation also causes an increase in the apparent granule content of catecholamines, suggesting the presence of composed fusion. Conversely, PKC activation promotes acceleration of the exocytotic process. We also analyzed the contribution of different Ca2+channel subtypes to the exocytotic kinetics at the single event level. Although N‐subtype channels do not contribute to total catecholamine release, their blockade produces a slowing down of exocytosis without changes in granule content. However, L or P/Q blockade causes, in addition, a reduction in the apparent granule content. The L‐type agonist BAY‐K‐8644 produces giant secretory amperometric spikes, indicating that Ca2+favors composed fusion prior to exocytosis. Our data suggest that second messengers continuously regulate exocytotic kinetics and granule content. In addition, several well‐known antihypertensive agents, such as sodium nitroprusside, organic nitrates, hydralazine, or Ca2+antagonists, could be acting through these novel mechanisms on sympathetic synapses by changing the synaptic performance, thereby producing additional vasodilatory effects.
The Role of Different Scinderin Domains in the Control of F‐Actin Cytoskeleton during Exocytosis
Authors: LEJEN T. , PENE T. DUMITRESCU , ROSÉ S. D. , TRIFARÓ J‐M.
Published: July 2009

Abstract: Scinderin (Sc), a Ca2+‐regulated actin‐binding protein, has been previously shown to control submembranous actin dynamics in regulated secretion. The results of the present study suggest the possibility that Sc might act as a molecular switch in the control of cortical F‐actin dynamics during secretion.
New Structure Involved in Transient Membrane Fusion and Exocytosis
Authors: CHO S‐J. , WAKADE A. , PAPPAS G. D. , JENA B. P.
Published: July 2009

Abstract: Our studies using atomic force microscopy (AFM) reveal a new group of plasma membrane structures involved in exocytosis in live pancreatic acinar cells. These studies demonstrate that “pits” and “depressions” are sites at the apical plasma membrane in live cells, where membrane‐bound secretory vesicles dock and transiently fuse to release vesicular contents.
Inositol 1,4,5‐Trisphosphate Receptor/Ca2+ Channel Modulatory Role of Chromogranins A and B
Authors: YOO SEUNG HYUN , SO SEUNG HO , HUH YANG HOON , PARK HEE YUN
Published: July 2009

Abstract: The secretory granules function as the major IP3‐sensitive intracellular Ca2+ store of secretory cells. Recently it was found that the secretory granules contain three isoforms of inositol 1,4,5‐trisphosphate receptor (IP3R)/Ca2+ channels and high‐capacity, low‐affinity Ca2+ storage proteins chromogranins A (CgA) and B (CgB). The IP3R/Ca2+ channel was shown to directly interact with CgA and CgB at the intragranular pH 5.5, and this coupling led to modulation of the IP3R/Ca2+ channel activity by the coupled chromogranins. These results provide the molecular structural basis of the IP3‐mediated Ca2+ release mechanism of secretory granules.
Vasostatins Exert Negative Inotropism in the Working Heart of the Frog
Authors: CORTI A. , MANNARINO C. , MAZZA R. , COLOMBO B. , LONGHI R. , TOTA B.
Published: July 2009

Abstract: An in vitro isolated working frog heart (Rana esculenta) was used to study the effects of exogenous CGA1‐76 (vasostatin 1), CGA1‐113 (vasostatin 2), and the synthetic CGA7‐57 on cardiac performance. Under basal cardiac conditions, the dose‐response curves of the three peptides from 10−8 to 10−7 M showed a significant calcium‐dependent negative inotropism that involved neither the endocardial endothelium nor the adrenergic and muscarinic receptors. In addition, the CgA fragments clearly counteracted the typical positive inotropism of isoprenaline (10−<9 M). Taken together, these results provide the first evidence for a cardio‐suppressive role for the vasostatins.
Plasticity of Pheochromocytoma Cell Lines from Neurofibromatosis Knockout Mice
Authors: POWERS JAMES F. , SCHELLING KIMBERLEY H. , BRACHOLD JAIME M. , TISCHLER ARTHUR S.
Published: July 2009

Abstract: Adrenergic mouse pheochromocytoma (MPC) cells from heterozygous neurofibromatosis knockout mice show little or no expression of the NGF receptor trk A and do not undergo neuronal differentiation in response to NGF. However, they express high levels of receptor tyrosine kinase, Ret, and GDNF family receptor α1 (GFRα1) in vivo and in vitro and respond to glial cell line—derived neurotrophic factor (GDNF). In addition, they form short processes in response to PACAP or cyclic AMP. Morphological effects of GDNF, PACAP, or cyclic AMP are similar to those of NGF, PACAP, or cyclic AMP on PC12 cells, and all three agents cause downregulation of PNMT mRNA. The MAP kinase kinase inhibitor U0126 inhibits both baseline proliferation and stimulated process outgrowth, consistent with a model in which sustained low‐level ERK activation drives proliferation, and more intense activation drives neuronal differentiation. The sensitivity of MPC cells to U0126 both may reflect mechanisms that cause pheochromocytomas in neurofibromatosis and aid in their clarification.
Mechanism of Sorting Proopiomelanocortin and Proenkephalin to the Regulated Secretory Pathway of Neuroendocrine Cells
Authors: LOH Y. PENG , MALDONADO ALEX , ZHANG CHUNFA , TAM WINNIE H. , CAWLEY NIAMH
Published: July 2009

Abstract: Proopiomelanocortin (POMC) and proenkephalin (PE) are synthesized at the endoplasmic reticulum and transported to the trans‐Golgi network (TGN) where they are sorted and packaged into dense‐core granules of the regulated secretory pathway (RSP). The mechanism of sorting POMC and PE to the RSP in neuroendocrine cells was investigated. Consensus sorting signals comprising two acidic residues and two hydrophobic residues exposed on the surface of N‐POMC1‐26 and N‐PE1‐32 were identified and shown to be sufficient and necessary for targeting POMC and PE to the RSP in PC12, Neuro2a, and AtT‐20 cells. The acidic residues of these sorting signals bind specifically to basic residues on the sorting receptor membrane, carboxypeptidase E (CPE), to effect sorting to the RSP. Analysis of POMC and PE sorting in Neuro2a cells depleted of CPE by CPE antisense RNA, and Cpefat/fat mouse pituitary cells lacking CPE showed missorting of both these molecules to the constitutive pathway in vivo. Thus, POMC and PE are sorted to the RSP at the TGN by a mechanism involving the interaction of a specific sorting signal on these molecules with the sorting receptor, CPE.
Role of Protein Kinases in Neuropeptide Gene Regulation by PACAP in Chromaffin Cells
Authors: HAMELINK CAROL , LEE HYEON‐WOO , HSU CHANG‐MEI , EIDEN LEE E.
Published: July 2009

Abstract:Pituitary adenylate cyclase—activating polypeptide (PACAP) is an adrenomedullary cotransmitter that along with acetylcholine is responsible for driving catecholamine and neuropeptide biosynthesis and secretion from chromaffin cells in response to stimulation of the splanchnic nerve. Two neuropeptides whose biosynthesis is regulated by PACAP include enkephalin and vasoactive intestinal polypeptide (VIP). Occupancy of PAC1 PACAP receptors on chromaffin cells can result in elevation of cyclic AMP, inositol phosphates, and intracellular calcium. The proenkephalin A and VIP genes are transcriptionally responsive to signals generated within all three pathways, and potentially by combinatorial activation of these pathways as well. The characteristics of PACAP regulation of enkephalin and VIP biosynthesis were examined pharmacologically for evidence of involvement of several serine/threonine protein kinases activated by cAMP, IP3, and/or calcium, including calmodulin kinase II, protein kinase A, and protein kinase C. Evidence is presented for the differential involvement of these protein kinases in regulation of enkephalin and VIP biosynthesis in chromaffin cells, and for a prominent role of the mixed‐function (tyrosine and serine/threonine) MAP kinase family in mediating transcriptional activation of neuropeptide genes by PACAP.
Catecholaminergic Pathways, Chromaffin Cells, and Human Disease
Authors: PARMER ROBERT J. , ZINDER OREN
Published: July 2009

Abstract: Recent studies demonstrate major effects of adrenal medullary and catecholaminergic pathways on a wide variety of normal physiologic and regulatory events. Alterations in these pathways, involving changes in catecholamines or in proteins and peptides costored and coreleased with catecholamines, may lead to profound changes in autonomic, cardiovascular, neuroendocrine, metabolic, nociceptive, and immune function. These findings have important implications for a variety of human disease states. In addition, molecules associated with catecholaminergic function may provide novel diagnostic and therapeutic strategies for human disease and suggest specific genetic loci as important and fruitful targets for further genetic and pharmacogenetic studies.
Virally Mediated Delivery of Enkephalin and Other Neuropeptide Transgenes in Experimental Pain Models
Authors: WILSON STEVEN P. , YEOMANS DAVID C.
Published: July 2009

Abstract: We have constructed recombinant herpes simplex virus type 1 vectors for delivery of genes to sensory neurons in an attempt to modulate nociception. Delivery of recombinant viruses to the skin of mice results in expression of encoded complementary DNA (cDNA) genes in DRG neurons within three to four days. Expression of marker genes persists for at least 10 weeks. Testing of baseline thermal nociceptive latencies at the site of virus application revealed no differences between a control virus and a virus encoding human preproenkephalin (hPPE) when performed at either low stimulus intensities (C‐fiber activation) or high stimulus intensities (Aδ neurons). By contrast, sensitization of nociceptors by capsaicin or dimethylsulfoxide was reduced or abolished by infection with the virus encoding hPPE, but not by a control virus. These antihyperalgesic responses are mediated by opioids released at the central terminals of the primary afferents because they are blocked by intrathecal administration of the opioid antagonist naloxone. Similar experiments performed in macaques demonstrated an antihyperalgesic effect of the herpes virus vector encoding hPPE. This hPPE‐encoding virus was also tested in a model of neuropathic pain in mice, with similar effect. A virus containing an antisense cDNA for calcitonin gene‐related peptide precursor (ACGRP) has also been constructed and found to reverse C‐fiber hyperalgesia caused by application of capsaicin to the skin for up to 14 weeks postinfection. These results raise the possibility that herpes‐mediated, gene‐based approaches to treat chronic pain states may be useful in therapy of chronic pain in humans.
Chromogranin A‐Activated Microglial Cells Induce Neuronal Apoptosis
Authors: ULRICH GABRIELLE , CIESIELSKI‐TRESKA JAROSLAVA , TAUPENOT LAURENT , BADER MARIE‐FRANCE
Published: July 2009

Abstract: Chromogranin (CgA), a protein upregulated in many neuropathologies, can induce an activated phenotype in microglial cells that leads to neuronal apoptosis. The death‐signaling pathways mobilized in neurons involve the death receptor Fas, p38 MAP kinase, and mitochondrial cytochrome c. We propose that CgA represents a potent endogenous inflammatory factor responsible for neuronal degeneration.
Science's Signal Transduction Knowledge Environment
Authors: GOUGH NANCY R.
Published: July 2009

Abstract: Knowledge environment (KE) describes the collection of electronic networking tools that have been and continue to be developed by AAAS and Stanford University libraries. Knowledge environments use practical, production‐quality tools to systematize the consensus knowledge within a scientific domain and facilitate users' access to that knowledge. Science's Signal Transduction Knowledge Environment (STKE) is the first in this new concept in electronic publishing that combines the traditional, albeit electronic, publishing of articles, such as reviews, perspectives, and protocols, with tools for organizing and collating information in the cross‐disciplinary field of signal transduction. One of the major tools developed for the STKE is the Connections Map database and the software (called CMADES [Connections Maps Authority Data Entry Software]) created to facilitate data entry by Pathway Authorities. The Connections Maps are a graphical representation of a database of information about the molecules involved in cellular signaling cascades. CMADES automates many of the functions involved in adding data into the Connections Maps database, such as references and descriptors, as well as allowing the Authorities to indicate the relationships between the components in the pathway through the use of a graphing tool. CMADES and the Connections Maps represent evolving tools that assist the Authorities in systemizing information regarding a particular system at the organism‐ and cell‐specific level and the canonical level, as well as provide the STKE user with organized and expert‐supplied information about signal transduction pathways.
Efficacy of Semliki Forest Virus Transduction of Bovine Adrenal Chromaffin Cells
Authors: DUNCAN RORY R. , GREAVES JENNIFER , TAPECHUM SOMPOL , APPS DAVID K. , SHIPSTON MICHAEL J. , CHOW ROBERT H.
Published: July 2009

Abstract: In using chromaffin cells as a model for studying the mechanism of regulated exocytosis, there is a requirement for an efficient, safe, and robust system for the transduction and expression of heterologous cDNA in these cells. We have used Semliki Forest virus to transduce cDNAs encoding various proteins fused to enhanced green fluorescent protein (EGFP) into cultured bovine adrenal cells. Transduction is highly efficient but has no significant effect on the steady state levels of several endogenous proteins or of catecholamines in the transfected cells. Furthermore, the transfected cells show depolarization‐induced calcium currents and nicotine‐induced catecholamine release. We present data to show that virally transduced proteins are targeted to their intracellular locations correctly in chromaffin cells. The fusion protein pro‐ANF‐EGFP is specifically targeted to large dense‐core vesicles as shown by its colocalization with acidophilic dyes and chromogranin A, making this a useful system for the study of secretory vesicle dynamics.
Simulation and Identification of Deterministic Structures in Thermal and Magnetic Convection
Authors: HANJALIĆ KEMAL , KENJEREŠ SAŠA
Published: July 2009

Abstract: Large‐scale vortical structures, found in many flows in nature, in laboratory or industrial equipment, have often a deterministic character. Simulation, identification, visualization, and interpretation of such structures is essential for understanding the physics of turbulence and transport processes, and for their control, but still poses a challenge especially in complex flows at high Reynolds and Rayleigh numbers. We show that such structures can be simulated by a transient Reynolds‐averaged Navier‐Stokes (T‐RANS) approach. Various structure‐identification methods show that the captured deterministic structures resemble closely those obtained from experiments or direct numerical simulations (DNS). The potential of the T‐RANS method is illustrated by examples of classical and magnetic Rayleigh‐Bénard (R‐B) convection in a range of Rayleigh numbers that are at present inaccessible to experiments or other simulation techniques.
Visualization of Molecular Dynamics by Simulation
Authors: OTA MASAHIRO , QI YINGXIA
Published: July 2009

Abstract: The mechanism of formation of methane hydrate is investigated here at a molecular level. The key to whether or not methane hydrates can be formed is the stability of the hydrate structure. This paper deals with a computer simulation of methane hydrate type 1 formation by a molecular dynamics method and an accurate description of the crystal structure. Computer simulation results show that very stable type 1 methane hydrates can be formed below 275 K, in which 46 water and 8 methane molecules are contained in a single cubic unit cell of length 12.0 Å. Above 275 K, the stability of the hydrates increasingly degrades, logarithmically as a power function, up to 300 K, with no stability at 350 K. Pressure, as a parameter of formation conditions, increases with temperature and becomes tremendously high at 350 K. Hydrates with various hydration numbers (at least one guest molecule in a small cage) have roughly the same degree of stability, but higher pressures are required for hydrates with fewer guest molecules. Empty hydrates dissolve above 275 K.
Visualization of Turbulent Wedges under Favorable Pressure Gradients Using Shear‐Sensitive and Temperature‐Sensitive Liquid Crystals
Authors: CHONG TZE‐PEI , ZHONG SHAN , HODSON HOWARD P.
Published: July 2009

Abstract: Turbulent wedges induced by a three‐dimensional surface roughness placed on a flat plate were studied using both shear sensitive and temperature sensitive liquid crystals, respectively denoted by SSLC and TSLC. The experiments were carried out at a free‐stream velocity of 28 m/sec at three different favorable pressure gradients. The purpose of this investigation was to examine the spreading angles of the turbulent wedges, as indicated by their associated surface shear stresses and heat transfer characteristics, and to obtain more insight about the behavior of transitional momentum and thermal boundary layers when a streamwise pressure gradient exists. It was shown that under a zero pressure gradient the spreading angles indicated by the two types of liquid crystals are the same, but the difference increases as the level of the favorable pressure gradient increases. The result from the present study is important for modelling the transition of thermal boundary layers over gas turbine blades.
Visualization and Measurement of Multiphase Flow in Porous Media Using Light Transmission and Synchrotron X‐Rays
Authors: DARNAULT CHRISTOPHE J.G. , DICARLO DAVID A. , BAUTERS TIM W.J. , STEENHUIS TAMMO S. , PARLANGE J.‐YVES , MONTEMAGNO CARLO D. , BAVEYE PHILIPPE
Published: July 2009

Abstract: Non‐aqueous phase liquids enter the vadose zone as a result of spills or leaking underground storage facilities, thus contaminating groundwater resources. Measuring the contaminant concentrations is important in assessing the risk to human health and the environment and to develop effective remediation. This research presents the development and application of the light transmission method (LTM) for three‐phase flow systems, aimed at investigating unstable fingered flow in a soil‐air‐oil‐water system. The LTM uses the hue and intensity of light transmitted through a slab chamber to measure fluid content, since total liquid content is a function of both hue and light intensity. Evaluation of the LTM is obtained by comparing experiments with LTM and synchrotron X‐rays. The LTM captures the spatial resolution of the fluid contents and can provide new insights into rapidly changing, two‐phase and three‐phase flow systems. Application of the LTM as a visualization technique for environmental and physical phenomena is noted. Visualization by LTM of groundwater remediation by surfactants as well as visualization of model cluster growth and fractal dimensions was also explored.
Modeling the Spreading Cortical Depression Wavefront
Authors: BAYSAL UGUR , HAUEISEN JENS
Published: July 2009

Abstract: Spreading cortical depression (SCD) is a wave of depolarization that spreads across the cortex at 2–5 mm/min and is followed by a 5–10 minute reduction in EEG activity. It is assumed that SCD is involved in the pathophysiology of migraine. We present a new model and a visualization technique for the spread of excitation on realistic brain surfaces. The usefulness of the technique is demonstrated on a rat brain that had been segmented from a three‐dimensional magnetic resonance image data set. With the help of this methodology it is possible to create specific patient models to better understand the mechanisms of SCD.
Time‐Varying Current Density Distributions in the Human Heart and Brain
Authors: HAUEISEN JENS , ZIOLKOWSKI MAREK , LEDER UWE
Published: July 2009

Abstract: A new method for visualizing and postprocessing three‐dimensional time varying vector fields is presented. This method is based on equivalent ellipsoids fitted to these fields. The new technique has been tested on vector fields representing current density reconstruction results based on biomagnetic data from a cardiac patient and a neurological patient. Multiple foci in the vector fields are extracted by multiple ellipsoids which are fitted in an iterative manner. The new method enables visualization of even very complex vector fields, as well as statistical postprocessing.
Microscopic Study of Crystal Growth in Cryopreservation Agent Solutions and Water
Authors: TAO LE‐REN , HUA TSE‐CHAO
Published: July 2009

Abstract: Ice formation inside or outside cells during cryopreservation is evidently the main factor of cryoinjury to cells. In the study described here a high voltage DC electric field and a cryomicroscopic stage were used to test DMSO and NaCl solutions under electric field strengths ranging from 83 kV/m to 320 kV/m. Dendritic ice crystals became asymmetric when the electric field was activated. This change in the ice crystal shape was more pronounced in the ionic NaCl solution. In addition, ice growth of distilled water without an electric field was tested under different cooling rates.
Visualization of Droplet Boiling on Heated Transparent Solid Surfaces with Various Thermal Properties
Authors: INADA SHIGEAKI
Published: July 2009

Abstract: The purpose of the research described in this paper is to elucidate the phenomenon of miniaturization boiling, which involves the scatter of a large number of minute liquid particles from a droplet surface to the atmosphere when the droplet impinges on a solid heating surface. This behavior was photographed from the underside of the heating surface, with special attention to the liquid‐solid contact. Transparent solid surfaces with various thermal properties included sapphire, glass with indium tin oxide coating, quartz, and quartz with chromium coating.
Visualization of Flow and Heat Transfer Augmentation by Oblique Impingement Jets
Authors: KIMOTO HIDEO , NUNTADUSIT CHAYUT , HAMABE KENJI
Published: July 2009

Abstract: Various nozzle geometries for impingement cooling jets have recently been devised and favorable designs for cooling effectiveness have been reported. However, impinging flow and the characteristics of impingement cooling are not sufficiently clear. This paper reports on an investigation of impingement jet cooling techniques. The impingement cooling characteristics by oblique jets through a rectangular nozzle have been clarified. Preliminary numerical simulations have not necessarily presented the details of heat transfer characteristics of the oblique jets.
Investigation of Transport Phenomena Inside a Microcapsule
Authors: GOUBERGRITS LEONID , AFFELD KLAUS , DEBAENE PERRINE , KERTZSCHER ULRICH
Published: July 2009

Abstract: Mass transfer within a microcapsule is enhanced by convection, achieved by introducing a movable body inside the microcapsule. This body has a different density from the fluid within the microcapsule and can be moved relative to the microcapsule by application of an external force, such as a magnetic field or acceleration/deceleration. The effect of the transport improvement was investigated as a function of the Peclet number (Pe) by using computational fluid dynamics and particle image velocimetry. The results show that the period to achieve 80% saturation in the microcapsule was reduced by 60% with a movable body with half of the diameter of the microcapsule and Pe= 600, compared to the mass transport in the microcapsule with a non‐movable body.
Numerical Visualization of Two‐Phase Plume Formation in a Stratification Flow Environment
Authors: CHEN BAIXIN , NISHIO MASAHIRO , SONG YONGCHEN , SOMEYA SATOSHI , AKAI MAKOTO
Published: July 2009

Abstract: Evolution of two‐phase plumes driven by air bubble buoyancy in a stratification ambient in a rectangular tank is visualized numerically by means of two‐phase flow theory and large‐eddy simulation technology. With a focus on the discrete nature of the buoyant dispersed phase and the role of momentum exchange between two phases in plume formation, we investigated the phenomena of mass entraining‐in and peeling‐out for continuous phase plume, which may result from a complicated and intricate interplay with phase interaction and dynamic stability of the stratification ambient, respectively. Numerical simulations show that although mass entraining‐in and peeling‐out appear to be distinguished entirely in the vertical direction, they interact or couple locally within inner of the plume and present a discontinuity in nature. The numerically visualized three‐dimensional density field also indicates the same plume characteristics.
Flow Characteristics of Two Immiscible Liquid Layers Subjected to a Horizontal Temperature Gradient
Authors: SOMEYA SATOSHI , MUNAKATA TETSUO , NISHIO MASAHIRO , OKAMOTO KOJI , MADARAME HARUKI
Published: July 2009

Abstract: Marangoni convection, driven by an interfacial instability due to a surface tension gradient, presents a significant problem in crystal growth in normal microgravity environments. It is important to suppress and control the convection phenomenon for better material processing, especially in crystal growth by the liquid encapsulated Czochralski or liquid encapsulated floating zone techniques, in which the melt is encapsulated in an immiscible medium. Marangoni convection can occur on the liquid‐liquid interface and on the gas‐liquid free surface. Buoyancy driven convection can also affect and complicate the flow. In the study we report here, experiments were carried out with two liquid layers, silicone oil and fluorinert, in an open and enclosed rectangular cavity. The flow in the cavity was subjected to a horizontal temperature gradient. The interactive flow near the liquid‐liquid interface was measured by the particle image velocimetry technique. The measured flow field is in agreement with numerical predictions. Free surface fluctuations with several dominant frequencies were also measured.
Further Immunohistochemical Evidence for Impaired NO Signaling in the Hypothalamus of Depressed Patients
Authors: BERNSTEIN H.‐G. , HEINEMANN A. , KRELL D. , MAWRIN C. , BIELAU H. , DANOS P. , DIEKMANN S. , KEILHOFF G. , BOGERTS B. , BAUMANN B.
Published: July 2009

Abstract: The cellular expression of nitric oxide synthase (NOS) was studied in neurons of the Nuc. suprachiasmaticus (SCN) of depressed patients and matched controls. The number of NOS‐immunoreactive SCN neurons was significantly reduced in depression. We conclude that affective disorders are accompanied by impaired hypothalamic NO signaling.
Nitric Oxide Production Stimulated by the Basic Fibroblast Growth Factor Requires the Synthesis of Ceramide
Authors: ARENA SARA , PATTAROZZI ALESSANDRA , THELLUNG STEFANO , VILLA VALENTINA , CORSARO ALESSANDRO , MASSA ALESSANDRO , DIANA FABRIZIO , SPOTO GIUSEPPE , FORCELLA SABRINA , DAMONTE GIANLUCA , FILOCAMO MIRELLA , BENATTI UMBERTO , SCHETTINI GENNARO , FLORIOA TULLIO
Published: July 2009

Abstract:Nitric oxide (NO) is an intracellular and intercellular mediator involved in the modulation of many physiologic and pathologic processes including the regulation of neoangiogenesis. We analyzed the effects of basic fibroblast growth factor (bFGF) on NO production in CHO‐K1 cells and the intracellular mechanisms involved. bFGF induces NO production through activation of the endothelial NO synthase (eNOS), causing a subsequent increase in cGMP levels. In most systems, eNOS activation is a Ca2+‐calmodulin‐dependent process. In CHO‐K1 cells, NO production by bFGF is Ca2+and MAP kinase independent, because it was not reverted by pretreatment with intracellular Ca2+chelators or MEK inhibitors. Translocation of the eNOS from the plasma membrane, where it is bound to caveolin 1, to the cytosol is the crucial step in the synthesis of NO. We demonstrate that the cytosolic translocation of eNOS is caused by increased synthesis of ceramide dependent by the bFGF activation of sphingomyelinase. Indeed, in the presence of the sphingomyelinase inhibitors D609 or desipramine, bFGF‐dependent NO production is abrogated. To support this evidence we evaluated ceramide concentration using HPLC‐electrospray ionization‐mass spectrometry in controls and in bFGF‐treated cells: after bFGF stimulation, a substantial increase in ceramide levels was observed. These data were further confirmed by the lack of NO production in response to fibroblast growth factor in fibroblasts derived from Niemann Pick patients who genetically lack the enzyme sphingomyelinase. In conclusion, ceramide in CHO‐K1 cells is responsible for a novel Ca2+/calmodulin‐independent mechanism for eNOS activation after fibroblast growth factor stimulation.
β‐Arrestin 1 Couples Thrombin to the Rapid Activation of the Akt Pathway
Authors: GOEL REEMA , BALDASSARE JOSEPH J.
Published: July 2009

Abstract: In a variety of cell types including chinese hamster embryonic fibroblasts (IIC9 cells), α‐thrombin is a potent mitogen. Thrombin irreversibly activates Par 1, a member of the seven membrane‐spanning superfamily of G protein‐coupled receptors (GPCRs). This, in turn, activates several heterotrimeric G proteins and induces signaling pathways that are critical for cell cycle reentry and proliferation. In IIC9 cells, α‐thrombin activates the phosphatidylinositol‐3‐OH kinase (PI 3‐Kinase)/Akt pathway, which is essential for G1 cell cycle progression. At present the mechanism for activation and regulation of the PI 3‐kinase/Akt pathway is not fully understood. My preliminary data demonstrates a role for β‐arrestin 1 in the regulation of α‐thrombin‐induced Akt activity. In addition to their importance in receptor down‐regulation, β‐arrestins are now known to scaffold proteins involved in stimulating specific signaling pathways. My preliminary data show that ≺‐thrombin activates a rapid Akt activity in a β‐arrestin 1‐dependent manner in IIC9 cells.
Activation of the p38 MAPK and ERK1/2 Pathways Is Required for Fas‐Induced IL‐8 Production in Colonic Epithelial Cells
Authors: O'BRIEN DARREN , O'CONNOR TERRY , SHANAHAN FERGUS , O'CONNELL JOE
Published: July 2009

Abstract: This paper aims to examine the contribution of all three of the MAP kinase signaling pathways to Fas‐induced IL‐8 up‐regulation in HT29 colon epithelial cells.
Signaling Pathways Leading to Apoptosis or Survival in Immature and Mature B Cells
Authors: SÁRMAY G. , KONCZ G. , BODOR Cs. , KÖVESDI D. , GÁTI R. , GERGELY J.
Published: July 2009

Abstract: In the absence of phosphorylated Gab2, immature B cells are unable to maintain a prolonged signal transduction, which is necessary for the transcriptional regulation and activation of the cells. Thus, the lack of Gab2 phosphorylation may drive immature B cells to apoptosis.