bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect ofd‐Amphetamine and Sydnocarb on the Extracellular Level of Dopamine, 3,4‐Dihydroxyphenylacetic Acid, and Hydroxyl Radicals Generation in Rat Striatum
Authors: ANDERZHAONOVA E. A. , AFANAS'EV I. I. , KUDRIN V. S. , RAYEVSKY K. S.
Published: July 2010

d‐AMPH and its congeners are able to produce several neurotoxic effects, including behavioral evidences of dopaminergic dysfunction, enhanced generation of reactive oxygen species, and depletion of endogenous DA. As has been shown, Sydnocarb produces a slow and gradual increase of the parameters of dopaminergic dysfunction. Present investigations report that Sydnocarb, the original Russian psychostimulant, at a dose of 23.8 mg/kg (equimolar to 5 mg/kgd‐AMPH) elicited a moderate increase in the extracellular level of DA. We found that Sydnocarb increased OH generation in less degree than that byd‐AMPH. Sydnocarb was also able to elicit stereotyped behavior, but to a less extent thand‐AMPH. Differences between the mode of action of this drug were previously observed. In our study, the DOPAC extracellular level was significantly decreased after the fourth injection of Sydnocarb, unlike withd‐AMPH treatment. Taken together, this finding probably reflects less neurotoxic potential of the novel, original psychostimulant Sydnocarb with good clinical efficaciousness in comparison to the amphetamine.
Prevention of Dopaminergic Neurotoxicity by Targeting Nitric Oxide and Peroxynitrite: Implications for the Prevention of Methamphetamine‐induced Neurotoxic Damage
Authors: IMAM SYED Z. , ISLAM FAKHRUL , ITZHAK YOSSEF , SLIKKER WILLIAM , ALI SYED F.
Published: July 2010

Methamphetamine (METH) is a neurotoxic psychostimulant that produces catecholaminergic brain damage by producing oxidative stress and free radical generation. The role of oxygen and nitrogen radicals is well documented as a cause of METH‐induced neurotoxic damage. In this study, we have obtained evidence that METH‐induced neurotoxicity is the resultant of interaction between oxygen and nitrogen radicals, and it is mediated by the production of peroxynitrite. We have also assessed the effects of inhibitors of neuronal nitric oxide synthase (nNOS) as well as scavenger of nitric oxide and a peroxynitrite decomposition catalyst. Significant protective effects were observed with the inhibitor of nNOS, 7‐nitroindazole (7‐NI), as well as by the selective peroxynitrite scavenger or decomposition catalyst, 5,10,15,20‐tetrakis(2,4,6‐trimethyl‐3,5‐sulfonatophenyl)porphyrinato iron III (FeTPPS). However, the use of a nitric oxide scavenger, 2‐phenyl‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide (c‐PTIO), did not provide any significant protection against METH‐induced hyperthermia or peroxynitrite generation and the resulting dopaminergic neurotoxicity. In particular, treatment with FeTPPS completely prevented METH‐induced hyperthermia, peroxynitrite production, and METH‐induced dopaminergic depletion. Together, these data demonstrate that METH‐induced dopaminergic neurotoxicity is mediated by the generation of peroxynitrite, which can be selectively protected by nNOS inhibitors or peroxynitrite scavenger or decomposition catalysts.
Dopamine Uptake Blockers Nullify Methamphetamine‐induced Decrease in Dopamine Uptake and Plasma Membrane Potential in Rat Striatal Synaptosomes
Authors: WESTPHALEN R. I. , STADLIN A.
Published: July 2010

Rat striatal synaptosomes showed a reduced capacity to generate a membrane potential after being exposed to methamphetamine (METH) for 1 h. As a consequence, the dopamine (DA) synaptosomes were impeded in their electrogenic‐dependent reuptake of dopamine. The capacity for METH‐exposed nerve terminals to generate a membrane potential may contribute to the ability of METH to destroy dopaminergic neurons. DA uptake inhibitors (DAUIs) were found to counteract the METH‐induced decrease in synaptosomal [3H]DA Vmax by stablizing METH‐induced reductions in PMP. Because DAUIs showed the same effects as a Na+‐channel blocker, DAUIs may prevent METH‐induced destruction of dopaminergic neurons by raising plasma membrane potential.
Age as a Susceptibility Factor in the Striatal Dopaminergic Neurotoxicity Observed in the Mouse following Substituted Amphetamine Exposure
Authors: MILLER DIANE B. , O'CALLAGHAN JAMES P. , ALI SYED F.
Published: July 2010

A number of substituted amphetamines, including methamphetamine (METH) are considered dopaminergic neurotoxicants. METH causes long‐term depletions of striatal dopamine (DA) and its metabolites (DOPAC and HVA) that are accompanied by other changes indicative of nerve terminal degeneration. These include argyrophilia as detected by silver degeneration stains and an elevation in glial fibrillary acidic protein (GFAP), a marker of reactive gliosis in response to injury, as well as a long‐term decrease in tyrosine hydroxylase (TH) protein levels. The susceptibility to the dopaminergic neurotoxicity of METH and the other amphetamines can be affected by a number of factors including age, gender, stress, and environment. Many of these susceptibility factors have been extensively investigated in the rat but less so in the mouse. As the availability of genetically altered mice continues to expand, this species is increasingly selected for study. Thus, in previous work we determined that stress, gender, and the environment can significantly impact the neurotoxicity of the amphetamines. Here we determined how age affects the striatal DA depletion and GFAP elevation induced byd‐METH in C57BL/6 mice. Age was a significant determinant of the ability of a known neurotoxic regimen ofd‐METH (10 mg/kg × 4) to produce striatal DA depletion with one‐month‐old C57BL/6 mice displaying minimal and nonpersistent depletion of DA or its metabolites while mice 12 months of age displayed large and persistent depletions of DA (87%), DOPAC (71%), and HVA (94%). Large elevations in striatal GFAP were induced in mice 2‐23 months of age byd‐METH, with lower dosages ofd‐METH being effective in the older mice. In contrast, the usual neurotoxic regimen ofd‐METH was minimally effective in inducing GFAP elevations (49% over control) in one‐month‐old mice, despite elevations in body temperature equivalent to those observed in older mice. Although increasing the dosage ofd‐METH (20 to 80 mg/kg) did increase the GFAP response (100% over control), it was still well below that usually exhibited at the usual neurotoxic dosage (300‐400% over control) in fully mature mice. These data suggest maturity of striatal dopamine systems may be an essential element in the striatal damage induced by the neurotoxic amphetamines.
Plasma Catecholamines during an Ultrarapid Heroin Detoxification
Authors: MACEDO T. R.A. , RELVAS J. , FONTES RIBIERO C. A. , PACHECO F. , MORGADINHO M. T. , PINTO C. M. , GOMES P. C. , VENTURA M. , HENRIQUES V. , NUNES S. V. , RUIS G. R. , RAMALHEIRA C. , BOTO I. , VALE L. L.
Published: July 2010

The adrenergic system has long been known to be activated in a situation of stress and thus during opiate withdrawal. A method for detoxification that decreases the stimulation of the sympathetic nervous system will prevent changes of catecholamine levels. Some of such methods have been developed. One of them uses direct transition from heroin to oral naltrexone after deep sedation with midazolam in conjunction with naloxone, droperidol, ondansetron, and clonidine treatment for 24 hours. Can such method prevent adrenergic changes? Moreover, 5‐HT has been related to mood disorders. This study aims to determine plasma catecholamines and 5‐HT before heroin withdrawal, during the day of the withdrawal, and at the ends of the first day, the first week, and the first 6 months. Forty‐three patients with more than 6 years of drug abuse volunteered to seek help to detoxify. After clinical evaluation, blood samples were taken. Plasma catecholamines were isolated by standard alumina procedures and measured by high‐performance liquid chromatography with electrochemical detection. Only for NE was there a significant decrease in the day of heroin withdrawal with deep sedation, followed the next day by an increase. During the following days, NE plasma concentrations returned slowly to basal levels. Epinephrine and dopamine plasma levels did not significantly change. Platelet 5‐HT levels progressively decreased from the day before detoxification until the last period of observation. We also found that there were no abrupt changes in cardiovascular functions. In conclusion, our results suggest that this type of ultrarapid opiate detoxification prevents the dramatic activation of the autonomic nervous system.
Ca2+Oscillations in Response to Methamphetamine in Dopamine Neurons of the Ventral Tegmental Area in Rats Subchronically Treated with This Drug
Authors: URAMURA KAZUHIDE , YADA TOSHIHIKO , MUROYA SHINJI , TAKIGAWA MORIKUNI
Published: July 2010

Mesolimbic dopamine neurons in the ventral tegmental area (VTA), which project to the nucleus accumbens and prefrontal cortex, play an important role in the regulation of emotion, rewarding, and cognition. The dopamine neurons in the VTA have also been implicated in schizophrenia and drug abuse. Methamphetamine (METH) can induce a schizophrenia‐like psychosis. Thus, the VTA is a likely effector site for the action of METH. However, effects of METH on the mesolimbic dopamine neurons are largely unknown. We treated adult SD rats with METH (5 mg/kg/day) or saline for 7 days, isolated single VTA neurons from these treated rats, and monitored the neuronal activities by measuring cytosolic Ca2+concentration ([Ca2+]i), which was followed by immunocytochemical identification of dopamine neurons. Acute administration of METH under superfusion conditions concentration‐dependently increased [Ca2+]iin VTA dopamine neurons isolated from METH‐ and saline‐treated rats. Furthermore, acutely administered METH induced oscillations of [Ca2+]ionly in the dopamine neurons of the METH‐treated group. The METH‐induced [Ca2+]ioscillations were inhibited by Ca2+‐free conditions and by Ca2+ channel blockers. In conclusion, subchronic METH treatment sensitizes VTA dopamine neurons to this drug, resulting in induction of [Ca2+]ioscillations. This sensitization of VTA dopamine neurons may account, at least in part, for the psycho‐stimulant effects of METH, such as the dependence on and sensitization to METH.
The Neurochemical Basis for the Behavioral Effects of Triadimefon
Authors: HILL DONNA , IKAIDDI MARGARETMARY , MAZZIO ELIZABETH , SOLIMAN KARAM F.A.
Published: July 2010

Administration of triadimefon (TDF) [1‐(4‐chlorophenoxy)‐3,3‐dimethyl‐1‐(1‐H‐1,2,4‐triazol‐1‐yl)‐2‐butanone] in rodents incites heightened locomotor and stereotypy response, primarily through potentiation of dopaminergic activity. In the present study, 8 male Sprague‐Dawley rats received repeated injections, on alternate days (100 mg/kg, 14 days) of TDF or corn oil. Enhanced locomotor and stereotypy behavioral patterns occurred in response to TDF injections, lasting until the 12thday of injection. Tolerance to this effect was evident by a lack of response to TDF injection by the 14thday. Similarly, a withdrawal period and challenge dose of TDF (5 days, 25 mg/kg) was ineffective in espousing locomotor or stereotypy behavioral changes. Cross sensitization to cocaine was also evident, since withdrawal and a challenge dose (8 days, 5 mg/kg) was also ineffective. Adaptative biochemical changes in dopaminergic function were examined after both acute (100 mg/kg) and repeated administration of TDF (100 mg/kg, 14 days) by examining [3H]dopamine (DA) uptake and DA release in both striatal (ST) and nucleus accumbens (NA) tissue. In corroboration with behavioral pattern indicating development of tolerance, there were significant changes in dopaminergic function. Repeated TDF exposurein vivoresulted in significant attenuation of ST and NA DA uptake in response to TDF (10−4to 10−7M) or cocaine (10−5to 10−8M)in vitro. Acute exposure to TDFin vivoalso attenuated ST DA inhibitory effects of cocaine and TDF. Repetitive administration of TDFin vivohad no effect onin vitroTDF‐ or amphetamine‐stimulated release of ST or NA DA. However, there was a significant reduction in amphetamine‐stimulated DA release in animals after acute exposure to TDFin vivo. It was concluded from this study that the effects of chronic TDF exposure may primarily involve effects on DA uptake in the ST and NA.
The Relationship between Neural Alterations and Behavioral Deficits after Prenatal Exposure to Heroin
Authors: YANAI JOSEPH , STEINGART RUTH A. , SNAPIR NACHUM , GVARYAHU GADI , ROZENBOIM ISRAEL , KATZ AMNON
Published: July 2010

The present studies employ multitudinous approaches in order to overcome the methodological obstacles in the understanding of the relationship between neurochemical alterations and behavioral deficits induced by heroin during prenatal development. Mice were exposed prenatally to heroin via daily subcutaneous injections of 10 mg/kg, on gestation days 9‐18. At age 50 days, the heroin‐exposed offspring displayed behavioral deficits as assessed in the eight‐arm and Morris mazes, pointing to possible alteration in the septohippocampal cholinergic innervations. Biochemically there was increased presynaptic activity of these innervations as attested to by the increased [3H]hemicholinium‐3 (HC‐3) binding sites and by K+‐stimulated inositol phosphate (IP) formation. Postsynaptically, there was global hyperactivation along the different components of the nerve conduction cascade, including an increase in M1 muscarinic receptor Bmax, a general increase in G‐proteins (GP) including the most relevant, Gq subtype, and an increase in IP formation and in basal protein kinase C (PKC) activity. However, there was desensitization of PKC activity in response to cholinergic agonist in the heroin‐exposed offspring. Transplantation of normal embryonic cholinergic cells to the impaired hippocampus reserved the behavioral deficits and both the pre‐ and postsynaptic hyperactivity and resensitized PKC activity.

To support and further strengthen the findings of the neural grafting study, correlation of the heroin‐induced behavioral deficits with the biochemical alterations, done within individuals, was applied. The results showed high |r|| values for IP formation, basal PKC, and PKC desensitization. The |r|| values for HC‐3 binding were statistically significant but relatively low. Taken together, the findings of the neural grafting and correlation studies bring us closer to understanding the relationship between the prenatal heroin‐induced biochemical and behavioral changes.

However, mammalian models possess the inherent methodological hindrances, stemming from possible maternal effects. To provide a control for these confounding variables, a chick embryo model was applied in which filial imprinting, a behavior related to a specific hyperstriatal nucleus, served as an endpoint. Heroin was administered to developing chick embryos by injecting the eggs (20 mg/kg) on incubation days (ID) 0 or 5. Prehatch exposure to heroin markedly diminished the ability for filial imprinting in the hatched chicks.
Short‐Term Regulation of NHE3 by EGF and Protein Kinase C but Not Protein Kinase A Involves Vesicle Trafficking in Epithelial Cells and Fibroblasts
Authors: DONOWITZ M. , JANECKI A. , AKHTER S. , CAVET M. E. , SANCHEZ F. , LAMPRECHT G. , ZIZAK M. , KWON W. L. , KHURANA S. , YUN C. H.C. , TSE C. M.
Published: July 2010

Abstract: NHE3 is an intestinal epithelial isoform Na+/H+ exchanger that is present in the brush border of small intestinal, colonic, and gallbladder Na+‐absorbing epithelial cells. NHE3 is acutely up‐ and downregulated in response to some G protein‐linked receptors, tyrosine kinase receptors, and protein kinases when studied in intact ileum, when stably expressed in PS120 fibroblasts, and in the few studies reported in the human colon cancer cell line Caco‐2. In most cases this is due to changes in Vmax of NHE3, although in response to cAMP and squalamine there are also changes in the K′ (H+)i of the exchanger. The mechanism of the Vmax regulation as shown by cell surface biotinylation and confocal microscopy in Caco‐2 cells and biotinylation in PS120 cells involves changes in the amount of NHE3 on the plasma membrane. In addition, in some cases there are also changes in turnover number of the exchanger. In some cases, the change in amount of NHE3 in the plasma membrane is associated with a change in the amount of plasma membrane. A combination of biochemical studies and transport/inhibitor studies in intact ileum and Caco‐2 cells demonstrated that the increase in brush border Na+/H+ exchange caused by acute exposure to EGF was mediated by PI 3‐kinase. PI 3‐kinase was also involved in FGF stimulation of NHE3 expressed in fibroblasts. Thus, NHE3 is another example of a transport protein that is acutely regulated in part by changing the amount of the transporter on the plasma membrane by a process that appears to involve vesicle trafficking and also to involve changes in turnover number.
Molecular Diversity of Plaques of Epithelial‐Adhering Junctions
Authors: BORRMANN CAROLA M. , MERTENS CLAUDIA , SCHMIDT ANSGAR , LANGBEIN LUTZ , KUHN CAECILIA , FRANKE WERNER W.
Published: July 2010

Abstract: In biochemical and immunocytochemical comparisons of adhering junctions of different epithelia, we have observed differences in molecular composition not only between the intermediate filament‐attached desmosomes and the actin filaments‐anchoring adherens junctions but also between desmosomes of different tissues and of different strata in the same stratified epithelium. In addition we now report cell type‐specific differences of molecular composition and immunoreactivity in both desmosomes and adherens junctions of certain simple epithelia. Whereas the zonula adhaerens of human intestinal and colonic epithelial cells, and of carcinomas derived therefrom, contains the additional armadillo‐type plaque protein ARVCF, this protein has not been detected in the zonula adhaerens of hepatocytes. Similarly, plakophilin 3 is present in the desmosomal plaques of intestinal and colonic cells but appears to be absent from the hepatocytic desmosomes. We suggest that these profound compositional differences in the junctions of related simple epithelia are correlated to functional differences of the specific type of epithelium.
Stress‐Induced Decrease of the Intestinal Barrier Function: The Role of Muscarinic Receptor Activation
Authors: GROOT JACK , BIJLSMA PIETER , KALKEREN ANNETTE VAN , KILIAAN AMANDA , SAUNDERS PAUL , PERDUE MARY
Published: July 2010

Abstract:Recently the breakdown of the barrier function of the intestinal epithelium after application of an experimental psychological and physical stress protocol in rats has been observed. Not only did smaller molecules pass from the luminal to the serosal side, but so also did larger proteins with the dimensions of luminal antigens and toxins. The increased permeability for macromolecules is primarily due to a decrease of the tightness of thezonula occludens, but an increased endocytotic uptake indicates that transcytosis is increased also. From studies of model systems it can be concluded that activation of the intracellular protein kinase C route by muscarinic receptor activation or histamine receptor activation can be one of the underlying cellular pathways. The physical pathway relaying the stress from the brain to the intestinal tract appears to be the parasympathetic branch of the autonomic nervous system. The difference in reaction of different strains suggests that coping style is an important determinant of the response of the intestinal barrier to stress.
Mechanisms of Cholera Toxin‐Induced Diarrhea
Authors: BEUBLER E. , SCHULIGOI R.
Published: July 2010

Abstract: In the pathogenesis of cholera, cyclic adenosine monophosphate, 5‐hydroxytryptamine, prostaglandins, and the function of neuronal structures have been implicated. To elucidate the role of different isoforms of cyclooxygenase (COX)‐1 and COX‐2, selective COX‐2 inhibitors were used. The selective COX‐2 inhibitors NS‐398 and DFU completely suppressed cholera toxin‐induced prostaglandin E2 biosysthesis and caused a dose‐dependent inhibition of cholera toxin‐induced fluid secretion in the rat jejunum in vivo. Constitutive expression of COX‐1 but also of COX‐2 mRNA was found in mucosal scrapings of the rat jejunum. Cholera toxin had no effect on COX‐1 as well as COX‐2 mRNA expression. Treatment of rats with dexamethasone did not effect cholera toxin‐induced prostaglandin E2 biosynthesis and did not influence the expression of COX‐2 mRNA, further substantiating that cholera toxin does not cause an induction of COX‐2 mRNA. Treatment of rats with E. coli lipopolysaccharide caused a marked increase in COX‐2 mRNA expression that was inhibited by dexamethasone. In conclusion, the results provide evidence that cholera toxin, in addition to other mediators, uses prostaglandin E2 to exert its secretory effect and that in the case of cholera toxin prostaglandins are metabolized via COX‐2.
Effects of Clostridium difficile Toxins on Epithelial Cell Barrier
Authors: POTHOULAKIS CHARALABOS
Published: July 2010

Abstract: Clostridium difficile is the primary agent responsible for many patients with antibiotic‐associated diarrhea and almost all patients with pseudomembranous colitis following antibiotic therapy. C. difficile infection is the most frequent form of colitis in hospitals and nursing homes and affects millions of patients in the United States and abroad. The first event in the pathogenesis of C. difficile infection involves alterations of the indigenous colonic microflora by antibiotics, followed by colonization with C. difficile. C. difficile causes diarrhea and colitis by releasing two high molecular weight protein exotoxins, toxin A and toxin B, with potent cytotoxic and enterotoxic properties. Evidence presented here indicates that C. difficile toxins compromise the epithelial cell barrier by at least two pathophysiologic pathways, one involving disaggregation of actin microfilaments in colonocytes via glucosylation of the Rho family of proteins leading to epithelial cell destruction and opening of the tight junctions, whereas the other appears to involve early release of proinflammatory cytokines from intestinal epithelial cells probably via activation of MAP kinases. We speculate that cytokines released from intestinal epithelial cells in response to toxin A exposure will diffuse into the lamina propria and activate macrophages, enteric nerves, and sensory neurons to release SP, CGRP, and NT, which, in turn, interact with immune and inflammatory cells and amplify the inflammatory response. Dissection of this inflammatory cascade may help us understand the pathophysiology of inflammatory diarrhea caused by this important pathogen.
Ion Transport during Growth and Differentiation
Authors: VENKATASUBRAMANIAN J. , SAHI J. , RAO M. C.
Published: July 2010

Abstract:The major function of the adult colon is to reabsorb fluid from the chyme. This ability to conserve salt and water is especially important in newborns, where reserves are small and diarrhea is frequent. Although much is known about regulation of Cl−transport in the adult colon, postnatal changes in electrolyte transport are not well characterized. We have established anin vitromodel to study colonic epithelial cells (colonocytes) at different stages of development. Primary cultures were isolated from newborn, weanling, and adult rabbit colon and properties such as growth and Cl−transport characterized. The isolation procedure yielded a crypt‐enriched population of cells, and the cell yield per gram mucosa increased with age. The colonocytes also showed an age‐related decrease in attachment to extracellular matrix, with maximum attachment seen with Matrigel and collagen IV. The crypt enrichment was confirmed by demonstrating that the cell population was capable of transporting Cl−, which was stimulated by agents such as forskolin and phorbol esters at all ages. Agents that increased intracellular cGMP, however, did not increase Cl−transport at any age. It was interesting to observe that the secondary bile acid, taurodeoxycholate, stimulated Cl−transport only in the adult but not newborn or weanling distal colonocytes. We have demonstrated that rabbit distal colonocytes can be kept viable in culture and transport Cl−at all ages. However, the regulation of Cl−transport changes during ontogeny and depends on the signaling pathway.
The Role of the OIE in International Trade
Authors: WILLIS NORMAN G.
Published: July 2010

Abstract: The OIE (Office International des Epizooties), the world animal health organization, has been addressing the most serious animal diseases throughout the globe for the past 75 years. It has developed guidelines for safe international trade in animals and animal products as part of its original mandate. Since the establishment of the World Trade Organization and the Sanitary and Phytosanitary Agreement, the role for the OIE has changed. At this point in the history of the OIE, new demands, expectations and challenges lie ahead as the OIE faces a new role in international trade.
The Impact of Diseases on the Importation of Animals and Animal Products
Authors: WALTON THOMAS E.
Published: July 2010

Abstract: For decades the veterinary services of the united states and other nations protected Their Livestock and poultry industries from the ravages of introduced animal diseases by rigorous import restrictions. this policy of zero risk frequently translated to no or reduced trade in animals and animal products or dramatic trade inequities. however, gatt articles enforced by the WTO require that imported products be treated no less favorably than domestically produced goods with regard to animal health restrictions. Under authority from the WTO, the OIE establishes recommendations and guidelines for the regulation of trade in animals and products of animal origin through the OIE International Animal Health Code, sets animal health standards, and reports global animal health situations and statuses. diseases often have a dramatic impact on the animal agricultural industries of a nation‐disease outbreaks may be deleterious to the competitiveness of the products of one nation but offer opportunities for others. the potential dangers of lax vigilance, insufficient scientifically valid data, inadequate sps measures, and errors in assessing risk can turn the heady experience of seemingly unlimited growth in international markets and demand for one's products into a catastrophic return to reality. The experience of the United Kingdom and countries of Europe with bovine spongiform encephalopathy is a case in point. It is estimated that the cost of the outbreak of this disease to the economy of the UK has been more than $3 billion. Responses of their trading partners, including the US, to this outbreak were abrupt and restrictive. Although the decision was controversial, the US stopped importation of live cattle from the UK in the late 1980'S and subsequently, in 1997, importation of all products of ruminant origin was stopped from all countries of europe. the transmission of the disease to continental europe and the disclosure that the pathogen was associated with a fatal human illness, rocked consumer confidence in the safety of the UK beef supply, brought down the ruling political party in the UK, and forced major changes in the beef industry.
A Perspective on Animal Protein Production in Sub‐Saharan Africa
Authors: TACHER G. , LETENNEUR L. , CAMUS E.
Published: July 2010

Abstract: A large survey of animal protein production in sub‐saharan Africa was performed. The objective was to identify specific production needed to ensure sustainable development. starting from data collection and analysis to gain control of this information, the study proposes possible paths of evolution for supply and demand for animal production. Africa will be the continent where the demand will grow the most (together with Asia), because of demography and urbanization. Urbanization will represent an extraordinary opportunity for the development of animal production. In 2020, the global demand will be 20 million tons per year (7.3 in 1994) for meat, 45 million tons for milk (18.6 in 1994) and 2.9 million tons for eggs (1.1 in 1994). Red meat, which now provides 55.6% of present meat consumption will satisfy only 36.5% in 2020. This underlines the immense effort needed to intensify ruminant production and/or to develop monogastric production. Consequently, there is a need in tropical animal health and research for better knowledge and control of monogastric diseases and particularly those linked to intensification. The development of peri‐urban milk production will require particular attention to hemoparasitic diseases. Globally, there is an urgent need to set up projects for the development of animal production.
The Increasing Significance of International Trade in Equids and Its Influence on the Spread of Infectious Diseases
Authors: TIMONEY PETER J.
Published: July 2010

Abstract: Expansion in international trade in equids and equine semen has been especially notable over the past 10‐15 years among those countries historically identified as having significant breeding and performance horse industries. the continuing trend towards globalization of the horse industry received additional impetus in january, 1995, following establishment of the World Trade Organization (WTO), whose primary goal is to promote freer economic exchange between member countries through the reduction or elimination of protectionist barriers to trade. Continued growth in international trade, closely related to changing trends in the horse industry, has greatly increased the risk of spread of a wide range of equine infectious diseases between countries. in consequence, the global distribution of certain of these diseases is likely to change in the future. Within the past 30‐40 years, there have been numerous confirmed instances of the spread of specific diseases through the international movement of equids or shipment of semen, some of which have resulted in epidemics of major economic importance. Under the Sanitary‐Phytosanitary Agreement of the WTO, national agencies have had to rethink their traditional “zero‐risk” approach in regulating the importation of equids or equine semen from other countries. Mindful of the risks of disease spread inherent in such transactions, authorities must now accept that primary emphasis in today's global economic climate must be on greater facilitation of trade, rather than attempting to provide absolute disease preventive safeguards.
Contagious Bovine Pleuropneumonia: A Reassessment of the Efficacy of Vaccines Used in Africa
Authors: THIAUCOURT F. , YAYA A. , WESONGA H. , HUEBSCHLE O. J.B. , TULASNE J. J. , PROVOST A.
Published: July 2010

Abstract: Contagious bovine pleuropneumonia is a major threat for cattle in Africa. Since 1956 the T1/44 strain has been used as a vaccine, and later on, T1sr, a streptomycin‐resistant variant that gives fewer post‐vaccinal reactions had been developed. These vaccines are known not to be very efficient but they normally should provide protection for about eight months. However, recent emergency vaccinations, performed in various countries in the southern part of the continent apparently met with failure, casting doubts on the identity as well as the protection afforded by the T1sr strain. A vaccine trial has been designed to reassess the real protection afforded by these vaccines in face of recently isolated pathogenic strains. Great care has been taken to test the original vaccinal strains at a dose corresponding to the minimum requirement by international standards. The test was performed in Cameroon, Kenya, and Namibia as to take into account the genetic diversity that exists among the pathogenic strains. In those conditions, the protection rate at three months varied from 33 to 67%, whatever the strain used, T1/44 or T1sr. These results call for additional research for vaccine development and careful planning of strategies in the fight against CBPP.
American Canine Hepatozoonosis: An Emerging Disease in the New World
Authors: EWING S. A. , PANCIERA R. J. , MATHEW J. S. , CUMMINGS C. A. , KOCAN A. A.
Published: July 2010

Abstract:Hepatozoon caniswas first described from dogs in 1905 in India andRhipicephalus sanguineuswas identified as the vector. Dogs on the Texas Gulf Coast were recognized in 1978 to have hepatozoonosis, and it was thought thatH. canishad entered the New World. Later, it was realized that American canine hepatozoonosis (ACH) is more debilitating than its Old World counterpart, often resulting in death. When the malady and parasite were characterized, a new species,H. americanum, was described, in 1997. Phylogenetic analysis, based on 18S rRNA gene sequence and classical taxonomic features, revealed that the two dog parasites are closely related.Amblyomma maculatum, the Gulf Coast tick (GCT), has been demonstrated to be an excellent vector; nymphal ticks were readily infected and oocysts from newly molted adults were uniformly infectious for dogs. The merogonic cycle ofH. americanumin dogs and the sporogonic development in the invertebrate host have been described. ACH is diagnosed primarily by histologic examination of skeletal muscle. Curative therapy is not available, but anti‐protozoal and anti‐inflammatory drugs may prolong life. Naturally infected coyotes have been found in Oklahoma and Texas, and experimental infections have been produced in this canid. Additional effort is needed to determine the vertebrate host range ofH. americanumand to define the enzootic cycle of which dogs have become a part; likewise, more work is required to determine whether larval GCTs can acquire infection and transmit it as nymphs.
Neosporosis: Aspects of Epidemiology and Host Immune Response
Authors: INNES ELISABETH A. , BUXTON DAVID , MALEY STEPHEN , WRIGHT STEPHEN , MARKS JOANNE , ESTEBAN IRMA , RAE ALISTAIR , SCHOCK ALEX , WASTLING JONATHAN
Published: July 2010

Abstract:Neospora caninumis a recently recognized protozoan parasite which has been described as causing a neuromuscular paralysis in dogs and is emerging as a major cause of bovine infertility and abortion worldwide. The parasite is known to infect a range of warm blooded animals but the disease predominates in dogs and cattle. It is not yet known ifN. caninumcan infect and cause disease in people. The dog has recently been identified as the definitive host and the parasite may be transmitted through the ingestion of oocysts or congenitally from mother to fetus.N. caninumis known to infect red foxes (Vulpes vulpes) and coyotes (Canis latrans) and the role of wildlife species as reservoirs of infection requires further investigation. Little is known about the range of parasite genotypes within the environment or the variation in virulence between different strains. RAPD‐PCR analysis of geographically distinct bovine and canine isolates has revealed little genetic variation. Epidemiological studies from different areas of the world have investigated the importance ofN. caninumas an abortifacient agent and longitudinal studies have shown the high rate (approximately 80%) of congenital transmission within infected herds. Information on the rates of repeat abortion due to neosporosis are less well defined however current estimates put this at 5% suggesting that cattle may develop some form of protective immunity againstN. caninum‐induced abortion. Diagnosis of the disease is based upon detection of the parasite in the tissues, most commonly using immunohistochemistry with additional information provided by serology. However, although positive fetal serology is a strong indicator of exposure to the parasite, care should be taken in the interpretation of maternal serology. As we understand more about the epidemiology of neosporosis we are also better able to interpret the results of diagnostic tests. The mere presence of the parasite does not necessarily infer that this was the primary cause of abortion. CD4+T‐cells, interferon gamma and macrophages have all been found to significantly inhibit multiplication ofN. caninumtachyzoites. The nature of a protective immune response and its modulation in the pregnant animal is discussed.
Cryptosporidiosis: A Global Challenge
Authors: MOSIER DEREK A. , OBERST RICHARD D.
Published: July 2010

Abstract:During the last 30 years, our concept of cryptosporidiosis has changed from that of a rare, largely asymptomatic disease, to an important cause of diarrhea in animals and humans worldwide. Significant disease first appeared in cattle. Subsequently, the zoonotic danger of the organism was recognized in HIV‐infected persons and young children.Cryptosporidiumare now ubiquitous and disease has been described in over 79 host species. Cryptosporidiosis has become a major cause of calfhood diarrhea worldwide. In humans it accounts for up to 20% of all cases of childhood diarrhea in developing countries and is a potentially fatal complication of AIDS. Waterborne contamination is a growing concern as a source of widespread outbreaks of disease. Factors that have contributed to the emergence of cryptosporidiosis in animals include biological features of the organism, the lack of an effective treatment or preventative, increased environmental contamination, and trends in livestock production. In humans the zoonotic nature of infection and an increased at‐risk population have contributed to disease. Genetic characterization ofCryptosporidium, improved detection methods, and a better understanding of the factors that predispose to disease are important contributions to understanding the epidemiology of cryptosporidiosis.
Development, Testing and Commercialization of a New Brucellosis Vaccine for Cattle
Authors: CHEVILLE NORMAN F.
Published: July 2010

Abstract:Vaccines used against brucellosis do not generally protect completely against infection or abortion. genetic analysis has revealed differences in arrangements of dna sequences between these vaccine strains and the virulent parent strain and permits the specific identification of field isolates ofB. abortusas wild‐type or vaccine strain.B. abortusstrain 19 is a low‐virulence, live vaccine developed for use in cattle. Although it is effective, strain 19 vaccine had a tropism for the placenta and caused abortion when given to pregnant cows, was infectious for humans, and caused serologic responses in calves that could not be differentiated from those in cattle infected with natural field strains. in the mid‐1980s the need for a new vaccine emerged when the USDA increased its efforts in brucellosis eradication. In the 1990s, research on biosafety, vaccine efficacy and field application rapidly established the fact that strain RB51 is protective in cattle at doses comparable to those of strain 19. Thus,Brucella abortusstrain RB51 is the vaccine of choice against brucellosis of cattle in the United States. Studies have established the relative efficacy of strain RB51 vaccine on bison, and the vaccine has also been accepted for use in commercial bison herds in the U.S.
Ethnoveterinary Medicine and Indigenous Pharmacopoeia of Passoré Province in Burkina Faso
Authors: TAMBOURA HAMIDOU H. , SAWADOGO L. L. , KABORÉ HENRI , YAMEOGO SALFO M.
Published: July 2010

Abstract: A study of traditional animal health care practices in Passoré province of Burkina Faso led to the characterization of 24 diseases, together with their local names, causes of their appearance, and their treatment. Most (95%) of the medicinal recipes used to treat affected animals were based on plants.
Humoral Immune Response of Dogs Immunized with Salivary Gland, Midgut, or Repeated Infestations with Rhipicephalus sanguineus
Authors: JITTAPALAPONG SATHAPORN , STICH ROGER W. , GORDON JOHN C. , BREMER CATHERINE A. , BARRIGA OMAR O.
Published: July 2010

Abstract: The antibody (Ab) responses of dogs immunized with adult tick salivary gland (TSG), midgut (TMG), or repeated infestations of Rhipicephalus sanguineus were monitored to determine if there is an association between Ab production and R. sanguineus performance. Tick‐naïve dogs were immunized with TSG or TMG and subjected to two challenge infestations. The control group was infested five times at 21‐day intervals. The ELISA technique was used to measure Ab levels in sera from these dogs, which expressed different forms of resistance against R. sanguineus. In dogs immunized with TSG or TMG, similar Ab levels were detected against TMG, TSG, muscle, synganglion, and reproductive organs. However, these sera had different Ab levels against egg mass, unfed larvae, fed larvae, and nymph antigens. Ab levels to muscle, nerve, and reproductive antigens were lower than those observed when TMG or TSG antigens were used. Sera from dogs immunized with TMG or TSG responded to most tick stages or tissue antigens, whereas repeated infestation sera showed the lowest response among the three groups.
Evaluation of a New Sandwich ELISA Kit That Uses Serum for Detection of Cattle Persistently Infected with BVD Virus
Authors: SALIKI JEREMIAH T. , HUCHZERMEIER ROY , DUBOVI EDWARD J.
Published: July 2010

Abstract: Cattle immunotolerant to and persistently infected (PI) with bovine viral diarrhea (BVD) virus (BVDV) constitute the mechanism by which BVDV persists in and spreads among cattle herds. Detection and elimination of PI cattle are necessary for control of BVD. Serum is an excellent specimen for BVD PI testing because of high survivability of BVDV in serum and ease of collection, storage, and handling. Currently, microtiter virus isolation (VI) employing serum and sandwich ELISAs (S‐ELISA) on tissues or leukocytes are used for BVDV PI screening. This paper evaluates a new S‐ELISA kit that uses serum as the diagnostic sample. Cattle sera (n= 408) were tested using VI and the S‐ELISA. The VI detected 172 BVDV‐positive sera. Of these, 18 were confirmed PI cattle. The S‐ELISA was positive on all PI samples. Considering only the PI animals, and using VI as the gold standard, the relative sensitivity of S‐ELISA was 100%. The overall relative sensitivity was 93.6% and the agreement quotient (κ) was 0.94. The relative specificity of the kit, based on 236 VI‐negative sera, was 100%. These data indicate that the new kit is very adequate for detection of BVDV PI cattle.
Comparison between c‐ELISA and CFT in Detecting Antibodies to Mycoplasma mycoides mycoides Biotype SC in Cattle Affected by CBPP in Botswana
Authors: AMANFU W. , SEDIADIE S. , MASUPU K. V. , RABOROKGWE M. V. , BENKIRANE A. , GEIGER R. , THIAUCOURT F.
Published: July 2010

Abstract: Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides mycoides biotype small colony (SC) (MmmSC) appears to be making a serious comeback in Africa after successful control programs in many parts of the continent during the 1960s and 1970s. Botswana, a country that has been free from the disease for more than 50 years, was affected in 1995. An eradication policy was adopted by the Government of Botswana in which 320,000 cattle in the affected district of Ngamiland, Northwestern Botswana were slaughtered. This was followed by a restocking exercise in which 70,000 cattle were sent to the outbreak areas as replacement stock. It became necessary to carry out serosurveillance in order to ensure that the disease did not reenter Botswana and to ensure that the replacement stock remained free from the disease. The specificity and sensitivity of the complement fixation test (CFT) in Botswana was assessed in 82 cattle affected by the disease and held in a double fenced quarantine camp. The newly developed competitive ELISA was made available to the National Veterinary Laboratory (NVL) through the FAO/IAEA Joint Division in Vienna, Austria. Using postmortem lesions as the gold standard and a 2 × 2 contingency table, the two tests were compared in terms of their sensitivity and specificity in detecting antibodies to MmmSC. The CFT was found to be slightly more sensitive than the c‐ELISA, and this could be related to the stage of the disease. A long‐term study comparing the progression of the disease with the two tests is, therefore, essential.
Conservation Medicine
Authors: DEEM SHARON L. , KILBOURN ANNELISA M. , WOLFE NATHAN D. , COOK ROBERT A. , KARESH WILLIAM B.
Published: July 2010

Abstract: The Field Veterinary Program (FVP) of the Wildlife Conservation Society (WCS) was created in 1989 to combat the wildlife disease and health problems that increasingly complicate the process of wildlife conservation. The FVP provides veterinary services for the more than 300 WCS conservation projects located in more than 50 countries around the world. Most of these projects are in tropical regions and many have a wildlife/domestic livestock component. Wildlife health care provided by the FVP staff includes (1) identifying critical health factors; (2) monitoring health status; (3) crisis intervention; (4) developing and applying new technologies; (5) animal handling and welfare concerns; and (6) training. Additionally, the staff of the FVP give expert advice to many governmental and non‐governmental agencies that are involved in setting policies directly related to wildlife health and conservation issues. In this paper, two FVP projects are presented as examples of studies that have increased our understanding of the role wildlife diseases may play in the health of livestock and human populations, as well as the role humans and livestock may play in the health of wildlife populations. Examples of the collaborative work between the FVP staff and scientists from many disciplines (e.g., acarologists, mycobacterium experts, ecologists, and biologists) are also presented.
A Study on the Time of Ovicidal Effect of Some Anthelmintics in Djallonke Sheep and Its Implication for the Control of Parasitic Helminth Infections
Authors: AGYEI A. D.
Published: July 2010

Abstract: The time lag between the administration of five different anthelmintics and the exertion of their ovicidal effect on worm eggs was monitored in five groups of Djallonke sheep. In this experiment, all the animals in all treated groups and an untreated control group were grazed together. Worm egg output and the number of infective strongylate nematode larvæ (L3s) recovered from fecal cultures from each group were observed every four hours for 72 h. The earliest time observed for the occurrence of ovicidal effect resulting in the absence of L3s in fecal cultures was 8 h after the administration of the anthelmintics. However, this time was not the same for all the anthelmintics. The implication of the results are discussed in relation to its application for worm control.
Anaplasmosis Control and Diagnosis in South Africa
Authors: DE WAAL DANIËL T.
Published: July 2010

Abstract:Anaplasmosis is widespread in South Africa with more than 99% of the total cattle population at risk. Five tick species have been experimentally shown to be capable of transmittingAnaplasmain South Africa. Mechanical transmission through blood contaminated instruments and biting flies also occurs. Vaccination againstAnaplasma marginaleby administration of anAnaplasma centralelive‐blood vaccine has been practiced in this country since 1912. Although generally a mild pathogen,Anaplasma centralecan cause severe clinical reactions following vaccination and also does not afford complete protection against allA. marginaleisolates. Anaplasmosis vaccine is routinely available in a deep‐frozen form and approximately 220,000 doses of vaccine are sold per annum. Microscopic examination of stained thin blood smears is still the most reliable and cost effective method of confirming a clinical diagnosis of anaplasmosis. Several diagnostic tests, such as the complement fixation tests, card agglutination test, and enzyme‐linked immunosorbent assay (ELISA) have been developed to identify carrier cattle. A competitive inhibition ELISA test, based on antibody binding to a recombinant MSP‐5 protein conserved amongAnaplasmaspecies, is routinely used at this laboratory.