References of "Desmecht, Daniel"
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See detailThe bovine (Bos taurus) CD11a-encoding cDNA: molecular cloning, characterisation and comparison with the human and murine glycoproteins
Fett, Thomas ULg; Zecchinon, Laurent ULg; Baise, Etienne ULg et al

in Gene (2004), 325

The bovine cDNA encoding CD11 a cell-surface glycoprotein involved in multiple leukocyte functions, was sequenced and compared with the human and murine sequences. Despite some focal differences, it ... [more ▼]

The bovine cDNA encoding CD11 a cell-surface glycoprotein involved in multiple leukocyte functions, was sequenced and compared with the human and murine sequences. Despite some focal differences, it shares all the main characteristics of its known mammalian homologs. Along with the bovine CD18-encoding cDNA, which is available for a long time, the sequence data provided here will allow the successful expression of bovine CD11a, thus giving the first opportunity to express the Bos taurus beta(2)-integrin CD11a/CD18 (LFA-1, alpha(L)beta(2)) in vitro as a tool to examine the specificities of inflammation in the bovine species. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailCharacterization of the caprine (Capra hircus) beta-2 integrin CD18-encoding cDNA and identification of mutations potentially responsible for the ruminant-specific virulence of Mannheimia haemolytica
Zecchinon, Laurent ULg; Fett, Thomas ULg; Baise, Etienne ULg et al

in Molecular Membrane Biology (2004), 21(5, Sep-Oct), 289-295

The leukocyte integrins play a critical role in a great number of cellular adhesive interactions during the immune response. We describe here the isolation and characterization of the caprine beta(2 ... [more ▼]

The leukocyte integrins play a critical role in a great number of cellular adhesive interactions during the immune response. We describe here the isolation and characterization of the caprine beta(2) (CD18) sub-unit, common to the leukocyte beta(2)-integrin family. The deduced 770-amino-acid sequence reveals a transmembrane protein with 80, 81, 83, 96 and 99% identity with its canine, murine, human, bovine and ovine homologues respectively. Analysis of CD18 sequences emphasizes the functional importance of the beta(2) sub-unit I-like domain, and included metal ion-dependent adhesion site-like motif and confirms that of the cytoplasmic tail. Moreover, comparisons of ruminant versus non-ruminant CD18 sequences allowed the identification of 16 potential mutation sites that could be held responsible for the unique virulence of Mannheimia haemolytica for ruminants. Mannheimiosis is known to be the major respiratory disease among ruminants, whereas it is not pathogenic for other mammals, an observation that has been attributed to a specific interaction between M. haemolytica leukotoxin and ruminants' CD18. Therefore, the data provided here offer the possibility to explore new avenues in studies based on the caprine model and provide key information for future studies aimed at elucidating the molecular mechanisms underlying the ruminant-specific virulence of M. haemolytica. [less ▲]

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See detailExtensive mast cell degranulation in bovine respiratory syncytial virus-associated paroxystic respiratory distress syndrome
Jolly, Sandra ULg; Detilleux, Johann ULg; Desmecht, Daniel ULg

in Veterinary Immunology and Immunopathology (2004), 97(3-4), 125-136

Bovine respiratory syncytial virus (BRSV) infection is an important cause of outbreaks of respiratory disease among calves. This virus commonly induces mild to severe respiratory signs but, in a ... [more ▼]

Bovine respiratory syncytial virus (BRSV) infection is an important cause of outbreaks of respiratory disease among calves. This virus commonly induces mild to severe respiratory signs but, in a substantial proportion of cases, is also reported to be associated with paroxystic respiratory distress syndrome (PRDS). The pathogenesis of this 'malignant' clinical form has not been fully elucidated. The present study aimed at determining whether mast cell (MC) degranulation plays a role in the physiopathologic cascade leading to the PRDS. Paired serum samples were taken in herds during outbreaks of severe respiratory diseases (acute sera) and 3 weeks after (convalescent sera). Based on seroconversion to BRSV and clinical picture, 67 pairs of sera were selected from calves with a BRSV-associated PRDS for circulating MC tryptase determination. A MC metachromatic score was measured in post-mortem lungs from animals died from a BRSV-associated PRDS (principals) and compared with reference scores obtained from healthy lungs (controls). Levels of tryptase were significantly higher in acute sera (26.6+/-12.4 mug/l) compared to convalescent sera (8.4+/-7.8 mug/l; P < 0.001). Metachromatic scores yielded significantly different results between controls and principals (P < 0.01), demonstrating a significant disappearance of metachromatic granules from lung MCs in principals. Taken together, these data demonstrate the presence of an extensive MC degranulation in BRSV-associated PRDS. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailConditional expression of type I interferon-induced bovine Mx1 GTPase in a stable transgenic vero cell line interferes with replication of vesicular stomatitis virus
Baise, Etienne ULg; Pire, Grégory; Leroy, Michael et al

in Journal of Interferon & Cytokine Research (2004), 24(9), 513-521

In some vertebrate species, type I interferon(IFN)-induced Mx gene expression has been shown to confer resistance to some single-stranded RNA (ssRNA) viruses in vitro. Because the bovine species is ... [more ▼]

In some vertebrate species, type I interferon(IFN)-induced Mx gene expression has been shown to confer resistance to some single-stranded RNA (ssRNA) viruses in vitro. Because the bovine species is subject to an exceptionally wide array of infections caused by such viruses, it is anticipated that an antiviral allele should have been retained by evolution at the bovine Mx locus. The identification of such allele may help in evaluating the real significance of the Mx genotype for disease resistance in vivo, in deciphering host-virus molecular interactions involved, or in improving innate disease resistance of livestock through marker-assisted selection. We validated a double transgenic Vero cell clone in which the bovine Mx1 reference allele is placed under control of the human cytomegalovirus (CMV) enhancer-promoter sequence containing elements from the bacterial tetracycline resistance operon to regulate transcription. In the selected clone, transgene repression was very tight, and derepression by doxycycline led to homogeneous 48-h duration expression of physiologic levels of bovine Mx1. Expression of the transgene caused a dramatic decrease in cytopathic efficiency and a 500-5000-fold yield reduction of the Indiana and New Jersey serotypes of vesicular stomatitis virus (VSV). To our knowledge, the transgenic clone developed here is the first ever reported that allows conditional expression of an Mx protein, thus providing a valuable tool for studying functions of Mx proteins in general and that of bovine Mx1 in particular. This latter may henceforward be included in the group of Mx proteins with authenticated anti-VSV activity, which offers new research avenues into the field of host-virus interactions. [less ▲]

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See detailGenomic structure, organisation, and promoter analysis of the bovine (Bos taurus) Mx1 gene
Gérardin; Baise, Etienne ULg; Pire, Grégory et al

in Gene (2004), 326

Some MX proteins are known to confer a specific resistance against a panel of single-stranded RNA viruses. Many diseases due to such viruses are known to affect cattle worldwide, raising the possibility ... [more ▼]

Some MX proteins are known to confer a specific resistance against a panel of single-stranded RNA viruses. Many diseases due to such viruses are known to affect cattle worldwide, raising the possibility that the identification of an antiviral isoform of a bovine MX protein would allow the implementation of genetic selection programs aimed at improving innate resistance of cattle. With this potential application in mind, the present study was designed to isolate the bovine Mx1 gene including its promoter region and to investigate its genomic organisation and promoter reactivity. The bovine Mx1 gene is made up of 15 exons. All exon-intron boundaries conformed to the consensus sequences. A PCR product that contained a approximately 1-kb, 5'-flanking region upstream from the putative transcription start site was sequenced. Unexpectedly, this DNA region did not contain TATA or CCAAT motifs. A computer scan of the region disclosed a series of putative binding sites for known cytokines and transcription factors. There was a GAAAN(1-2)GAAA(C/G) motif, typical of an interferon-sensitive responsive element, between -118 and -107 from the putative transcription start site. There were also a NF-kappaB, two interleukin-6 binding sites, two Sp1 sites and five GC-rich boxes. The region also contained 12 stretches of the GAAA type, as described in all IFN-inducible genes. Bovine Mx1 expression was assessed by Northern blotting and immunofluorescence in the Madin Darby bovine kidney cells (MDBK) cell line treated with several stimuli. In conclusion, the bovine Mx1 gene and promoter region share the major structural and functional characteristics displayed by their homologs described in the rainbow trout, chicken, mouse and man. [less ▲]

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See detailLa myopathie atypique des équidés: particularités cliniques, examens complémentaires et hypothèses étiologiques.
Votion, Dominique ULg; Delguste, Catherine ULg; Amory, Hélène ULg et al

in Journée AVEF (Association des Vétérinaires Equins Français) (2003, October)

La myopathie atypique (MA) des équidés, encore appelée myoglobinurie atypique des chevaux au pré, est un syndrome caractérisé par l’apparition soudaine de faiblesse musculaire, de raideur, de tremblements ... [more ▼]

La myopathie atypique (MA) des équidés, encore appelée myoglobinurie atypique des chevaux au pré, est un syndrome caractérisé par l’apparition soudaine de faiblesse musculaire, de raideur, de tremblements et de sudation profuse généralisée ou localisée. L’animal adopte rapidement une position en décubitus sternal ou latéral. Lorsque de l’urine est émise, celle-ci a une couleur brune « chocolatée ». L’examen clinique révèle fréquemment de la tachycardie, de l’hypothermie et de la dyspnée. Le dosage de l’activité sérique de la créatinine kinase contribue à la présomption de MA en démontrant une destruction musculaire massive mais le diagnostic définitif repose nécessairement sur l’examen histologique des muscles intervenant dans la posture et la respiration, muscles généralement atteints lors de cette maladie ainsi que sur l’examen du muscle cardiaque où des lésions de dégénérescence sont occasionnellement observées. Diverses hypothèses étiologiques sont en cours d’investigation et les plus probables incriminent l’action d’une mycotoxine ou d’une toxine d’origine bactérienne, ingérée ou produite dans le tractus digestif. Néanmoins, une carence nutritionnelle n’est pas exclue. Quelle que soit la cause, il semble que des conditions climatiques défavorables favorisent le déclenchement des symptômes. La récolte de données épidémiologiques permettra de mieux définir les moyens de prévention de cette maladie souvent fatale. [less ▲]

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See detailDifferential diagnosis of neurologically expressed disorders in Western European cattle
Saegerman, Claude ULg; Claes, L.; Dewaele, Albert et al

in Revue Scientifique et Technique (International Office of Epizootics) (2003), 22(1), 83-102

A classification of neurological or neurologically expressed disorders that occur in Western European cattle aged 12 month and over has been established on the basis of aetiology, frequency and conditions ... [more ▼]

A classification of neurological or neurologically expressed disorders that occur in Western European cattle aged 12 month and over has been established on the basis of aetiology, frequency and conditions of appearance, age and type of animals concerned and the main clinical signs observed. Neurologically expressed disorders have been classified according to different groups of causes: biological, non-biological and non-specific or unknown. Differential diagnosis of neurologically expressed disorders is an essential element in the clinical epidemiological surveillance of bovine spongiform encephalopathy. A growing number of aetiologies are described in the scientific literature. The identification and centralised management of neurological disorders will make it possible, one the one hand, to take account of the inherent variability in the clinical forms encountered and in the diagnostic approaches of the observers and, on the other hand, to identify new risk factors in order to control them. [less ▲]

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See detailModulating skeletal muscle mass by postnatal, muscle-specific inactivation of the myostatin gene.
Grobet, Luc ULg; Pirottin, Dimitri ULg; Farnir, Frédéric ULg et al

in Genesis (2003), 35(4), 227-38

By using a conditional gene targeting approach exploiting the cre-lox system, we show that postnatal inactivation of the myostatin gene in striated muscle is sufficient to cause a generalized muscular ... [more ▼]

By using a conditional gene targeting approach exploiting the cre-lox system, we show that postnatal inactivation of the myostatin gene in striated muscle is sufficient to cause a generalized muscular hypertrophy of the same magnitude as that observed for constitutive myostatin knockout mice. This formally demonstrates that striated muscle is the production site of functional myostatin and that this member of the TGFbeta family of growth and differentiation factors regulates muscle mass not only during early embryogenesis but throughout development. It indicates that myostatin antagonist could be used to treat muscle wasting and to promote muscle growth in man and animals. [less ▲]

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See detailL'herpèsvirus alcélaphin 1, l'agent responsable de la forme africaine du coryza gangreneux
Dewals, Benjamin G ULg; Boudry, Christel ULg; Markine-Goriaynoff, Nicolas ULg et al

in Annales de Médecine Vétérinaire (2003), 147(1, FEB-MAR), 1-15

Malignant catarrhal fever (MCF) is a pathology usually lethal which has been described in a large number of ruminant species. Based on the etiology, two main forms of MCF have been described, i.e., the ... [more ▼]

Malignant catarrhal fever (MCF) is a pathology usually lethal which has been described in a large number of ruminant species. Based on the etiology, two main forms of MCF have been described, i.e., the European and the African forms due to ovine herpesvirus 2 (OvHV-2) and alcelaphine herpesvirus 1 (AlHV-1), respectively. The present review is devoted to the African form of MCF and to its causative agent AlHV-1. AlHV-1 belongs to the Gammaherpesvirinae subfamily of the Herpesviridae family. Wildebeests (Connochaetes spp) carry AlHV-1, which is lethal for a large number of ruminant species, while apparently harmless to its natural host. In hosts susceptible to MCF, the pathology is characterized by fever, extensive lymphadenopathy, ulcerative lesions of the digestive and the upper respiratory tracts mucous membranes and severe keratoconjunctivitis. In the present paper, we will review the data available to date on AlHV-1 and on the African form of MCF with emphasis on the pathogenesis, clinical signs and anatomo-pathological lesions of MCF. Finally, we will discuss the relationship between AlHV-1 and wildebeest as an example of symbiosis between a virus and its natural host. [less ▲]

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See detailEpisode de dyspnée consécutive à une intoxication par l’ergot dans une exploitation laitière
Brihoum, Mounir ULg; Desmecht, Daniel ULg; Bony, S. et al

in Annales de Médecine Vétérinaire (2003), 147(5), 353-358

A chronic consumption (3.5 months) of ergot (Claviceps purpurea) contaminated triticale in dairy cows resulted in dyspnea, mainly expiratory, consistent with interstitial pneumonia and emphysema. These ... [more ▼]

A chronic consumption (3.5 months) of ergot (Claviceps purpurea) contaminated triticale in dairy cows resulted in dyspnea, mainly expiratory, consistent with interstitial pneumonia and emphysema. These troubles can be compared to many observations done in humans after long lasting treatments with ergot derivatives [less ▲]

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See detailDiagnostic différentiel des troubles à expression nerveuse dans l’espèce bovine en Europe occidentale
Saegerman, Claude ULg; Claes, L.; Dewaele, A. et al

in Revue Scientifique et Technique (International Office of Epizootics) (2003), 22(1), 61-82

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See detailEffect of somatic growth, strain and sex on double-chamber plethymosgraphic respiratory function values in healthy mice
Flandre, Th.; Leroy, Pascal ULg; Desmecht, Daniel ULg

in Journal of Applied Physiology (2003), 94(3), 1129-1136

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See detailDiagnostic différentiel en cas de présomption de myopathie atypique des équidés : illustration au travers de cas référés à la Faculté de Médecine Vétérinaire de l’Université de Liège au cours du printemps 2003
Votion, Dominique ULg; Delguste, Catherine ULg; Baise, Etienne ULg et al

in Annales de Médecine Vétérinaire (2003), 147

Atypical myopathy is a frequently fatal disease inducing extensive and severe muscular damage, occurring during autumn and spring in grazing horses. The main features of the syndrome are the sudden onset ... [more ▼]

Atypical myopathy is a frequently fatal disease inducing extensive and severe muscular damage, occurring during autumn and spring in grazing horses. The main features of the syndrome are the sudden onset of non pathognomonic symptoms such as weakness, stiffness, sudation, recumbency and when observed, emission of dark urine. Confirmation of the diagnosis is of paramount importance since the disease can be recurrent on limited geographic area. This paper discusses the methodology applied on 7 clinical cases referred with a symptomatology suggestive of atypical myopathy to the Faculty of Veterinary Medicine at Liege University during the spring 2003. Two of those cases were confirmed for atypical myopathy. A presumption of atypical myopathy may be drawn on history and clinical signs. On living animals, the serum concentration of the creatinine phosphokinase enzyme is the most useful biochemical tests as an aid to diagnosis because it confirms the presence of muscle damage. Nevertheless, the definitive diagnosis requires the histological examination of specific muscular samples obtained post-mortem. [less ▲]

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See detailEffect of histamine on lung contractile elements in growing cattle
Jolly, Sandra ULg; Robinson, Edward; Desmecht, Daniel ULg

in American Journal of Veterinary Research (2003), 64

OBJECTIVE: To determine the effect of histamine on the contractile elements of the respiratory tract in neonatal calves and young adult cattle. SAMPLE POPULATION: Samples of trachealis muscle, bronchi ... [more ▼]

OBJECTIVE: To determine the effect of histamine on the contractile elements of the respiratory tract in neonatal calves and young adult cattle. SAMPLE POPULATION: Samples of trachealis muscle, bronchi, and intrapulmonary arteries and veins dissected from the respiratory tracts of healthy bovids (2 to 8 days and 16 to 20 months old). PROCEDURE: Histamine cumulative concentration-effect curves (10(-6) to 10(-3) M) were constructed in duplicate smooth muscle samples mounted in organ baths. Contractile responses to histamine were compared with reference contractions elicited by methacholine (10(-5) M) for airways or KCl (127 mM) for vessels. RESULTS: In young adult cattle, trachealis muscle had a substantial contractile response to histamine (84% of methacholine-induced contraction), whereas bronchi reacted slightly (15 and 20% for large and small bronchi, respectively). Although contractile responses to KCl were comparable in arteries and veins, histamine-induced contractions were greater for intrapulmonary veins than for arteries (202 vs 48% of KCl-induced contraction). In neonatal calves, histamine-induced contraction of veins also exceeded that of arteries (230 vs 54% of KCl-induced contraction); however, unlike in young adult cattle, histamine produced notable contraction of large and small bronchi (48 and 60% of methacholine-induced contraction, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Compared with intrapulmonary arteries, intrapulmonary veins have greater contractile responses to histamine in neonatal and young adult cattle. Data suggest loss of histamine responsiveness in bronchial smooth muscle as neonatal calves grow to young adults. Venodilation may be useful in treatment of lung edema in cattle. [less ▲]

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See detailEffect of somatic growth, strain and sex on double-chamber plethysmographic respiratory function values in healthy mice
Flandre, Thierry; Leroy, Pascal ULg; Desmecht, Daniel ULg

in Journal of Applied Physiology (2003), 94

Double-chamber plethysmography has been recognized since 1979 as a reference technique to measure pulmonary function values in guinea pigs, but it has not gained attention for use in mice. Theoretically ... [more ▼]

Double-chamber plethysmography has been recognized since 1979 as a reference technique to measure pulmonary function values in guinea pigs, but it has not gained attention for use in mice. Theoretically, however, this technique combines the advantages of single-chamber plethysmography with a quantitative assessment of flow and/or volume and a calculated resistance, the interpretation of which in terms of bronchoconstriction is not disputed. Here we show that, when appropriately preconditioned, mice are able to gradually grow accustomed to the apparatus and display extremely stable nasal and thoracoabdominal flow tracings. Overall, strain, sex, and somatic growth had a significant effect on pulmonary function values. The changes in specific airway resistance (sRaw) and enhanced pause (Penh) values were never in the same direction, indicating that they measure different things. The respiratory frequency was far higher in C57BL/6 compared with BALB/c mice. Peak flows, minute volume, specific tidal and minute volumes, and sRaw were also higher, but Penh was smaller. Males breathed at a higher frequency than females, leading to a higher minute volume. Nevertheless, the specific volumes were considerably higher among females. Penh was lower in males, whereas sRaw was identical in both sexes. Changes associated with somatic growth were rapid and important between 5 and 9 wk, then slowed down between 9 and 12-13 wk and became almost imperceptible after. [less ▲]

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See detailFunctional identification of epithelial and smooth muscle histamine-dependent relaxing mechanisms in the bovine trachea, but not in bronchi
Jolly, Sandra ULg; Desmecht, Daniel ULg

in Comparative Biochemistry & Physiology Part C : Toxicology & Pharmacology (2003), 134(1), 91-100

Theoretically, the overall effect of histamine on respiratory smooth muscle is the result of a subtle balance of contraction and relaxation. The aim of the study was to identify histamine type 2 (H2) and ... [more ▼]

Theoretically, the overall effect of histamine on respiratory smooth muscle is the result of a subtle balance of contraction and relaxation. The aim of the study was to identify histamine type 2 (H2) and 3 (H3) receptor-dependent relaxing mechanisms in the contractile elements of the bovine tracheobronchial tree. In bronchial preparations, histamine induced very weak contractions, which were not exacerbated with the H2-antagonist cimetidine. Moreover, precontracted bronchial rings never relaxed in response to cumulative doses of histamine or amthamine (H2-agonist). In intact tracheal preparations, histamine induced strong contractions that were exacerbated by cimetidine (E-max : + 17.2 +/- 6.6%) but not by thioperamide (H3-antagonist). Precontracted tracheal bundles did not relax in response to cumulative doses of the H3-agonist R-alpha-methylhistamine. The tracheal contractile response was higher in denuded compared to intact preparations (11.0+/-1.2 vs. 6.0+/-1.7 g). Cimetidine effect was dramatically potentiated in denuded tracheal strips (+40.0+/-11.7%). It is concluded that the weak response. of bovine bronchi to histamine is due to a relative scarcity of H1 receptors on bronchial smooth muscle rather than to H2- or H3-dependent relaxation. In the bovine trachea, the smooth muscle possesses relaxing H2 but no H3 receptors. The epithelium exercises a relaxation, which is independent from H2 and H3 receptors. (C) 2002 Elsevier Science Inc. All rights reserved. [less ▲]

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See detailInfiltrative lipoma in the foreleg of a horse
Olle, Edwin; Saunders, Jimmy; Desmecht, Daniel ULg

in Vlaams Diergeneeskundig Tijdschrift (2002), 71

This case report describes an infiltrative lipoma in a horse. A slow-growing mass, detected early afterbirth, was present at the caudal aspect of the foreleg (antebrachium) of a 2-year-old gelding ... [more ▼]

This case report describes an infiltrative lipoma in a horse. A slow-growing mass, detected early afterbirth, was present at the caudal aspect of the foreleg (antebrachium) of a 2-year-old gelding. Cytological fea-tures were that of a benign lipoma. Surgical resection was attempted but failed due to the infiltrative natureof the mass. Consequently, the horse was euthanized. Histopathology revealed an infiltrative lipoma. Thistumor is histologically benign but surgical resection is usually impossible due to its infiltrative nature. [less ▲]

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See detailLocal administration of nuclear factor-kB decoy oligodeoxinucleotides prevents allergic airway inflammation
Bureau, Fabrice ULg; Gosset, P.; Desmet, Christophe ULg et al

in 12th European Respiratory Society Annual Congress (2002)

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See detailMetabolic and Structural Abnormalities in Dogs with Early Left Ventricular Dysfunction Induced by Incessant Tachycardia
Mc Entee, Kathleen ULg; Flandre, Thierry; Doizé, Cécile ULg et al

in American Journal of Veterinary Research (2001), 62(6), 889-94

OBJECTIVE: To assess morphologic and metabolic abnormalities in dogs with early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP). ANIMALS: 7 Beagles. PROCEDURE: Plasma ... [more ▼]

OBJECTIVE: To assess morphologic and metabolic abnormalities in dogs with early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP). ANIMALS: 7 Beagles. PROCEDURE: Plasma carnitine concentrations were measured before and after development of ELVD induced by RRVP. At the same times, transvenous endomyocardial biopsy was performed, and specimens were submitted for determination of myocardial carnitine concentrations and histologic, morphometric, and ultrastructural examination. RESULTS: In 4 dogs in which baseline plasma total carnitine concentration was normal, RRVP induced a decrease in myocardial total and free carnitine concentrations and an increase in myocardial esterified carnitine concentration. In 3 dogs in which baseline plasma total carnitine concentration was low, plasma and myocardial carnitine concentrations were unchanged after pacing. Structural changes associated with pacing included perinuclear vacuolization in 3 dogs. Morphometric analyses indicated there was a decrease in myofiber cross-sectional diameter and area following pacing. Electron microscopy revealed changes in myofibrils and mitochondria following pacing. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that moderate to severe alterations in myocyte cytoarchitecture are present in dogs with ELVD induced by RRVP and that in dogs with normal plasma carnitine concentrations, myocardial carnitine deficiency may be a biochemical marker of ELVD. Results also indicated that transvenous endomyocardial biopsy can be used to evaluate biochemical and structural myocardial changes in dogs with cardiac disease. [less ▲]

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See detailEffect of Intravenous Platelet-Activating Factor on Bovine Pulmonary Mast Cells
Jolly, Sandra ULg; Thomas, Cédric; Genicot, Bruno et al

in Journal of Comparative Pathology (2001), 125(Aug-Oct), 81-89

The effect of platelet-activating factor (PAF) on bovine pulmonary mast cells (MCs) was investigated in calves aged 1-4 months. PAF was administered over a 5-min period at a rate of 50 ng/kg/min to six ... [more ▼]

The effect of platelet-activating factor (PAF) on bovine pulmonary mast cells (MCs) was investigated in calves aged 1-4 months. PAF was administered over a 5-min period at a rate of 50 ng/kg/min to six animals, which were killed approximately 10 min later. No macroscopical lesions were observed in the lung tissue of five control calves. On semi-thin toluidine-blue stained sections, MC cytoplasm showed profuse deep-blue granulation. In the lung tissues of PAF-treated calves, striking interstitial, alveolar and interlobular oedema and emphysema were observed. MC granules occurred at the periphery of the cytoplasm and MC nuclei were easily detectable. Moreover, the number of granules in the MC cytoplasm was remarkably low. A few granules with some metachromatic material were sometimes detected outside the cell limits. Ultrastructurally, the matrix pattern of the MC granules in lung tissues of control calves was either amorphous or granular. In lung tissues of the PAF-treated calves, the granular matrix pattern was pronounced, varying from fine- to coarse-grained, and the MCs were of reduced size, with many filiform processes and exocytotic vesicles. These findings indicate that pulmonary MC degranulation was induced by PAF in healthy calves. [less ▲]

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