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1.
Trop Anim Health Prod ; 53(1): 185, 2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33641034

RESUMEN

Rabbit haemorrhagic disease virus (RHDV) was recovered from necropsied rabbits that died during an outbreak characterized by epistaxis, incoordination, paralysis, and multi-organ haemorrhages in Ilorin, Nigeria. The haemagglutination test (HA) and RT-PCR assay targeted against a fragment of the RHDV VP60 gene were performed on liver, spleen, and kidney homogenates; faeces; and urine obtained from the rabbits. Amplicons were purified, sequenced, and phylogenetically analysed. The liver homogenates yielded the highest HA titres while RT-PCR of liver, spleen, and kidneys yielded the expected 1252 bp band. Sequence and phylogenetic analyses revealed that the Nigerian RHDV strain (RHDV/NGR/ILN/001) was 98.57%, 97.95%, and 96.70% homologous with RHDV2 (RHDVGI.2) strains from the Netherlands, Germany, and France, respectively. RHDV/NGR/ILN/001 induced tracheal, intestinal, and mediastinal lymph node haemorrhages, pulmonary oedema and congestion, and enlarged, necrotic liver in experimentally inoculated rabbits. The implications of this study, which is the first report of RHDV in Nigeria, are discussed.


Asunto(s)
Infecciones por Caliciviridae , Virus de la Enfermedad Hemorrágica del Conejo , Animales , Infecciones por Caliciviridae/epidemiología , Infecciones por Caliciviridae/veterinaria , Brotes de Enfermedades , Virus de la Enfermedad Hemorrágica del Conejo/genética , Nigeria/epidemiología , Filogenia
2.
J Econ Entomol ; 111(2): 716-724, 2018 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-29361020

RESUMEN

Pheromone components of cerambycid beetles are often conserved, with a given compound serving as a pheromone component for multiple related species, including species native to different continents. Consequently, a single synthesized compound may attract multiple species to a trap simultaneously. Furthermore, our previous research in east-central Illinois had demonstrated that pheromones of different species can be combined to attract an even greater diversity of species. Here, we describe the results of field bioassays in the northeastern, midwestern, southeastern, south-central, and southwestern United States that assessed attraction of cerambycids to a 'generic' pheromone blend containing six known cerambycid pheromone components, versus the individual components of the blend, and how attraction was influenced by plant volatiles. Nineteen species were attracted in significant numbers, with the pheromone blend attracting about twice as many species as any of the individual components. The blend attracted species of three subfamilies, whereas individual components attracted species within one subfamily. However, some antagonistic interactions between blend components were identified. The plant volatiles ethanol and α-pinene usually enhanced attraction to the blend. Taken together, these experiments suggest that blends of cerambycid pheromones, if selected carefully to minimize inhibitory effects, can be effective for sampling a diversity of species, and that plant volatiles generally enhance attraction. Such generic pheromone blends may serve as an effective and economical method of detecting incursions of exotic, potentially invasive species.


Asunto(s)
Escarabajos , Control de Insectos/instrumentación , Feromonas , Animales , Monoterpenos Bicíclicos , Etanol , Control de Insectos/estadística & datos numéricos , Masculino , Monoterpenos , Estados Unidos
4.
J Interferon Cytokine Res ; 19(8): 943-51, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10476942

RESUMEN

The purpose of this investigation was to examine the safety and efficacy of four dosages of natural human interferon-alpha (nHuIFN-alpha) delivered over a 12-week period orally in lozenges (150 IU and 450 IU, once [QD] or three times [TID] daily) compared to placebo in subjects with primary Sjögren's syndrome. This randomized, double-blinded clinical trial demonstrated that nHuIFN-alpha at a dose of 150 IU administered TID by oral lozenge significantly improved stimulated whole saliva output compared to placebo after 12 weeks of treatment. The 150 IU TID dose also was suggestive of benefit for 5 of 7 subjective measures of oral and ocular comfort. IFN lozenges demonstrated a good safety profile, with no serious adverse events found in any treatment group. There were no significant differences between the placebo and the four doses of IFN for adverse events by total number, organ system, severity, dropouts, and number judged to be related to treatment. In conclusion, these results demonstrated that the use of 150 IU IFN lozenges TID for 12 weeks in subjects with primary Sjögren's syndrome improved salivary output and decreased complaints of xerostomia without causing significant adverse medical events.


Asunto(s)
Interferón-alfa/uso terapéutico , Síndrome de Sjögren/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Interferón-alfa/efectos adversos , Masculino , Persona de Mediana Edad , Mucosa Bucal/efectos de los fármacos , Saliva/metabolismo , Tasa de Secreción/efectos de los fármacos
5.
J Interferon Cytokine Res ; 19(8): 961-8, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10476944

RESUMEN

One hundred and twelve fibromyalgia syndrome (FMS) patients were randomized into one of four demographically similar groups (n = 28/group). Sequential primary FMS patient volunteers were to receive daily sublingual placebo or interferon-alpha (IFN-alpha) at 15, 50, or 150 IU. After a screening evaluation, analgesic or sedative hypnotic medications were withdrawn. Two weeks later, daily IFN-alpha or placebo was initiated with follow-up evaluations at 2-week intervals ending with week 6. One primary, three secondary, and seven tertiary variables were assessed. Study outcome was based on improvement in the tender point index (TPI). The TPI did not improve with any IFN-alpha dose. However, significant improvement was seen in morning stiffness and in physical function with the 50 IU IFN-alpha (p < 0.01). None of the other outcome means changed significantly and no adverse events were attributable to IFN-alpha therapy.


Asunto(s)
Fibromialgia/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Fenómenos Fisiológicos Musculoesqueléticos/efectos de los fármacos , Administración Sublingual , Adolescente , Adulto , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Interferón-alfa/efectos adversos , Masculino , Persona de Mediana Edad , Síndrome , Resultado del Tratamiento
6.
J Interferon Cytokine Res ; 19(8): 969-78, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10476945

RESUMEN

A clinical study was designed to utilize flow cytometric immunophenotyping and chromium release from cultured tumor target cells to characterize peripheral blood mononuclear leukocyte (PBML) subpopulations and natural killer activity in healthy normal controls (n = 18) and in patients with fibromyalgia syndrome (FMS) at baseline (n = 124) and again after 6 weeks of treatment with low-doses of orally administered human interferon-alpha (IFN-alpha). Volunteer subjects discontinued all analgesic and sedative hypnotic medications for 2 weeks prior to the baseline phlebotomy. Laboratory measures included a complete blood count; a phenotypic analysis of PBML by flow cytometry; and in vitro natural killer (NK) cell activity. After baseline blood sample collection, the FMS patients were randomized to one of four parallel treatment groups (n = 28/group) to receive sublingual IFN-alpha (15 IU, 50 IU, 150 IU), or placebo every morning for 6 weeks. The tests were repeated at week 6 to evaluate treatment effects. At baseline, FMS patients exhibited fewer lymphocytes and more CD25+ T lymphocytes than did normal controls. By week 6, the main significant and consistent change was a decrease in the HLA-DR+ CD4+ subpopulation in the 15 IU and 150 IU treatment groups. These data do not support an immunologically dysfunctional PBML phenotype among patients with FMS as has been observed in the chronic fatigue syndrome.


Asunto(s)
Antígenos de Superficie/sangre , Fibromialgia/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Células Asesinas Naturales/efectos de los fármacos , Linfocitos/efectos de los fármacos , Administración Sublingual , Adolescente , Adulto , Anciano , Biomarcadores , Estudios de Casos y Controles , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Fibromialgia/inmunología , Citometría de Flujo , Humanos , Inmunofenotipificación , Células Asesinas Naturales/inmunología , Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Síndrome
7.
Arch Ophthalmol ; 98(9): 1617-20, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7425925

RESUMEN

A patient with advanced renal failure and bilateral exophthalmos was found to have urinary obstruction caused by retroperitoneal fibrosis, as well as bilateral orbital pseudotumors. Pseudotumor of the orbit, especially when bilateral, has been associated with a wide variety of systemic conditions. Although the association of pseudotumor and retroperitoneal fibrosis is uncommon, any patient with bilateral orbital pseudotumor and renal insufficiency should be examined for the possible presence of a treatable urinary obstruction.


Asunto(s)
Exoftalmia/complicaciones , Enfermedades Orbitales/complicaciones , Fibrosis Retroperitoneal/complicaciones , Anciano , Femenino , Humanos , Fallo Renal Crónico/complicaciones , Músculos Oculomotores/patología , Enfermedades Orbitales/diagnóstico , Enfermedades Orbitales/patología , Esclerosis , Obstrucción Ureteral/complicaciones , Obstrucción Ureteral/terapia
8.
Brain Res Bull ; 47(1): 43-7, 1998 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-9766388

RESUMEN

Physiological studies indicate that neurons in the upper cervical spinal cord have descending projections to the lumbosacral spinal cord and mediate inhibition of dorsal horn neurons activated from afferent input. In the present study, retrograde tracing techniques were used to examine the distribution of propriospinal neurons in C1-C2 spinal segments that project to lumbosacral spinal segments. Fluorogold or horseradish peroxidase were injected unilaterally or bilaterally into the L5-S1 spinal segments. After 2-4 days, rats were perfused with fixative and C1-C2 spinal segments were processed for retrograde labeling. Numerous neurons were found in the C1-C2 segments. In unilaterally and bilaterally injected rats, retrogradely labeled neurons were located on both the ipsilateral and contralateral sides. Retrogradely labeled neurons were located in the following locations: lateral cervical and spinal nuclei, nucleus proprius, ventral horn and the central gray region (area X). These studies demonstrate a descending projection from C1-C2 segments to the lower lumbar and sacral spinal cord. We hypothesize that many of these C1-C2 propriospinal neurons are important in modulating responses of spinal neurons at lower segmental levels to various peripheral stimuli.


Asunto(s)
Neuronas/fisiología , Propiocepción/fisiología , Médula Espinal/fisiología , Estilbamidinas , Animales , Colorantes Fluorescentes , Peroxidasa de Rábano Silvestre , Región Lumbosacra , Masculino , Ratas , Ratas Sprague-Dawley , Médula Espinal/citología
9.
Br J Ophthalmol ; 78(2): 95-8, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8123633

RESUMEN

Cataract surgery is performed more easily if mydriasis can be maintained until the intraocular lens has been inserted. Intraocular irrigation with adrenaline is thought to be of benefit in this respect, and is used by some surgeons but not others. This prospective double blind controlled trial assessed the efficacy and safety of using perioperative adrenaline during extracapsular cataract surgery, as an adjunct to preoperative topical mydriatics. Seventy patients were randomised to receive intraocular irrigation fluid with or without 1:1,000,000 adrenaline. The adrenaline entering the eye through the anterior capsulotomy needle helped to resist the miosis induced by expression of the nucleus (7.1 versus 6.5 mm). The mydriasis maintained during irrigation aspiration was significantly greater in the group receiving adrenaline (6.6 versus 6.0 mm, p < 0.02). Their pupil diameters were also significantly larger at 20 minutes (p < 0.001) and 30 minutes (p < 0.01) into surgery. Pupillary constriction to a diameter of less than 5 mm occurred more frequently in the group not receiving adrenaline. Pulse rate and blood pressure in the 27 patients who had local anaesthesia showed no significant difference between the treatment groups (p > 0.05), and there was no significant variation from baseline (p > 0.05). Intraocular irrigation with adrenaline 1:1,000,000 is a safe and effective means of maintaining mydriasis during cataract surgery.


Asunto(s)
Extracción de Catarata , Epinefrina/administración & dosificación , Pupila/efectos de los fármacos , Administración Tópica , Anciano , Método Doble Ciego , Femenino , Humanos , Cuidados Intraoperatorios , Masculino , Estudios Prospectivos , Irrigación Terapéutica , Resultado del Tratamiento
10.
Br J Ophthalmol ; 67(3): 203-5, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6824626

RESUMEN

The concentrations of clobetasone butyrate and betamethasone were measured in aqueous humour of patients undergoing cataract extraction 12.5 to 18.5 hours after application into the lower conjunctival sac of an ointment containing 0.1% of the steroid. Samples were assayed from 10 patients receiving clobetasone butyrate and 13 patients receiving betamethasone phosphate. There were measurable concentrations in only 2 samples in the former group, and both were 0.1 ng/ml. In the betamethasone group measurable concentrations were found in 11 samples, and the concentrations ranged from 0.5 to 20.3 ng/ml, with the highest concentrations between 12.5 and 13.5 hours after application. The concentration of betamethasone in the aqueous humour decreased by about 90% in the 6 hours from 12.5 to 18.5 hours after application. It is speculative as to whether it is these differences in pharmacokinetic behaviour, or other differences in biological or physicochemical properties, which are responsible for the minimal effect on intraocular pressure induced by clobetasone butyrate compared with betamethasone.


Asunto(s)
Antiinflamatorios/metabolismo , Humor Acuoso/metabolismo , Betametasona/análogos & derivados , Clobetasol/metabolismo , Anciano , Betametasona/metabolismo , Extracción de Catarata , Clobetasol/administración & dosificación , Clobetasol/análogos & derivados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pomadas , Factores de Tiempo
11.
Br J Ophthalmol ; 63(10): 687-9, 1979 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-508679

RESUMEN

Cefuroxime (Zinacef) is a new second generation cephalosporin which is resistant to beta-lactamases produced by both Gram-negative and Gram-positive organisms, with an antibacterial spectrum that includes practically all likely ocular pathogens except pseudomonas. It is shown to penetrate into the eye after intravenous (1.5g) or intramuscular (1 g) injection and achieve therapeutic concentrations, with absence of side effects. Cefuroxime is therefore a useful antibiotic for ophthalimic infections and should have a role in combination with gentamicin in intraocular infections, particularly those of unknown aetiology.


Asunto(s)
Humor Acuoso/metabolismo , Cefuroxima/metabolismo , Cefalosporinas/metabolismo , Adulto , Anciano , Cefuroxima/administración & dosificación , Cefuroxima/sangre , Femenino , Humanos , Inyecciones Intramusculares , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad
12.
Arch Immunol Ther Exp (Warsz) ; 41(3-4): 193-7, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8129561

RESUMEN

Fifty-six calves, seronegative for infectious bovine rhinotracheitis (IBR) virus, were randomly divided into 7 equal groups (n = 8) and given 0.0, 0.05, 0.50, or 5.00 international units (IU) of natural or recombinant human interferon alpha per kg body weight (nHuIFN-alpha or rHuIFN-alpha, respectively) orally once daily for 4 consecutive days, starting 2 days before intranasal inoculation with virulent IBR virus. Calves given 0.05 IU nHuIFN-alpha/kg bwt had significantly greater weight gain at days 15 (P < 0.10) and 25 (P < 0.05) than the placebo-treated (0.0 IU) control group. The treatment groups given 0.05 and 0.5 IU nHuIFN-alpha/kg bwt nHuIFN-alpha had fewer days with temperature > 40 degrees C (P < 0.05 and P = 0.10, respectively), and lower mean rectal temperatures on days 8 and 11 (0.05 IU/kg bwt; P < 0.10) or on day 11 (0.5 IU/kg bwt; P < 0.10). None of the calves given 0.05 IU nHuIFN-alpha/kg bwt required antibiotic therapy. Calves given 0.50 IU/kg bwt of nHuIFN-alpha, or 0.05 IU/kg bwt of rHuIFN-alpha had fewer (P < 0.05) total days of antibiotic therapy compared to controls. These data indicate that low dose oral IFN-alpha treatment significantly reduced the clinical effects of IBR virus infection in feedlot cattle in an interferon dose-dependent fashion.


Asunto(s)
Rinotraqueítis Infecciosa Bovina/terapia , Interferón-alfa/uso terapéutico , Administración Oral , Animales , Anticuerpos Antivirales/sangre , Temperatura Corporal/efectos de los fármacos , Bovinos , Ingestión de Alimentos/efectos de los fármacos , Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/sangre , Interferón Tipo I/uso terapéutico , Interferón-alfa/metabolismo , Masculino , Proteínas Recombinantes , Aumento de Peso/efectos de los fármacos
13.
Vet Immunol Immunopathol ; 45(3-4): 355-60, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7676616

RESUMEN

During a natural outbreak of transmissible gastroenteritis (TGE), groups of piglets were treated orally for 4 consecutive days with placebo or 1.0, 10.0 or 20.0 international units (IU) natural human interferon alpha (nHuIFN alpha). Piglets that were 1-12 days of age and given 1.0, 10.0 or 20.0 IU nHuIFN alpha had significantly (P < 0.01) greater survival rates than placebo-treated piglets; survival rates were the greater for the highest level of nHuIFN alpha treatment. In contrast, beneficial effects of nHuIFN alpha were not observed in piglets farrowed during the disease outbreak and given nHuIFN alpha within hours of birth. Oral nHuIFN alpha therapy modulates the natural course of high morbidity and mortality commonly seen with TGE.


Asunto(s)
Brotes de Enfermedades/veterinaria , Gastroenteritis Porcina Transmisible/terapia , Interferón-alfa/uso terapéutico , Administración Oral , Animales , Animales Recién Nacidos , Femenino , Gastroenteritis Porcina Transmisible/epidemiología , Interferón-alfa/administración & dosificación , Masculino , Pronóstico , Tasa de Supervivencia , Porcinos , Texas/epidemiología
14.
Food Chem Toxicol ; 40(7): 871-98, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12065209

RESUMEN

This paper contains a review of the history, natural occurrence, human consumption, metabolism, manufacture, and the results of eight standardized animal safety studies using trehalose. Trehalose (alpha,alpha-trehalose) is a naturally occurring sugar containing two D-glucose units in an alpha,alpha-1,1 linkage. Trehalose functions in many organisms as an energy source or a protectant against the effects of freezing or dehydration. It also possesses physical and/or chemical properties that are different than other sugars, which may make trehalose an attractive ingredient in food, health and beauty and pharmaceutical products. Data are presented supporting safe human consumption of trehalose in doses up to 50 g, and the physiologic ability of humans to digest it. No consistent treatment-related, dose-dependent adverse effects were observed in any of the eight safety studies performed at doses up to 10% of the diets. On the basis of these toxicity studies, human studies in which doses of trehalose were administered to various populations, and consumption of trehalose in commercial products in Japan, it is concluded that trehalose is safe for use as an ingredient in consumer products when used in accordance with current Good Manufacturing Practices.


Asunto(s)
Trehalosa/administración & dosificación , Animales , Femenino , Humanos , Masculino , Pruebas de Toxicidad , Trehalosa/efectos adversos
15.
Eur J Ophthalmol ; 4(1): 29-34, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7912576

RESUMEN

Ibopamine is a dopaminergic mydriatic of proven use for fundoscopy. This double-blind prospective trial assessed its efficacy and safety as a preoperative mydriatic agent. 105 patients undergoing extracapsular cataract surgery were randomly allocated to receive Ibopamine 1%, Ibopamine 1% with Cyclopentolate 1%, or the control Phenylephrine 10% with Cyclopentolate 1%. Ibopamine alone achieved good mydriasis prior to anaesthesia, but this was not maintained intraoperatively. Cyclopentolate combined with Ibopamine, produced consistently greater mydriasis than when combined with Phenylephrine, but the difference became less marked as surgery continued. Analysis in relation to the stage of surgery showed that the greatest stimulus to miosis occurred during expression of the nucleus. Pulse rate and blood pressure in the 51 local anaesthetic cases showed no significant difference between the treatment groups, and there was no significant variation from baseline. The incidence of local side effects was similar in the three groups, and there were no systemic symptoms attributable to the drops. In conclusion, Ibopamine is a safe and effective mydriatic agent for cataract surgery, when used in combination with Cyclopentolate.


Asunto(s)
Extracción de Catarata , Desoxiepinefrina/análogos & derivados , Dopaminérgicos/administración & dosificación , Pupila/efectos de los fármacos , Anciano , Ciclopentolato/administración & dosificación , Desoxiepinefrina/administración & dosificación , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Iris/efectos de los fármacos , Lentes Intraoculares , Masculino , Soluciones Oftálmicas , Fenilefrina/administración & dosificación , Estudios Prospectivos
16.
Am J Vet Res ; 47(6): 1217-24, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3729121

RESUMEN

In vitro interactions of bovine pulmonary lavage cells (PLC) and pathogenic isolates of Pasteurella haemolytica biotype A, serotype 1, were examined, using a luminol-dependent chemiluminescence (LDCL) assay. The PLC containing high concentrations of bovine alveolar macrophages were incubated with living and heat-killed P haemolytica at bacteria to PLC ratio of approximately 1:1. Kinetics of the mean LDCL response of bovine PLC to heat-killed P haemolytica cells were characterized by a gradual increase in the amount of light emitted over 150 minutes followed by a slight decrease at 180 minutes. In contrast, the LDCL responses of reaction mixtures containing living P haemolytica were characterized by the development of a maximal response at 60 minutes followed by a continued precipitous decrease in light emission to background values by 150 minutes. Differences were not noticed in the LDCL response of PLC suspensions from the same cow to 3 P haemolytica isolates. In each instance, reaction mixtures containing heat-killed bacteria had a similar LDCL profile that was characterized by continuous production of light over 180 minutes, whereas all reaction mixtures containing living bacteria underwent a precipitous decrease in light emission, which eventually resulted in a complete cessation of chemiluminescence. The PLC suspensions from different cattle did not respond to bacterial stimuli uniformly, with respect to the amplitude or detailed nature of the LDCL profile. The time that lapsed between the addition of living P haemolytica to PLC suspensions and the complete cessation of chemiluminescence varied for different cows.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Enfermedades de los Bovinos/microbiología , Macrófagos/fisiología , Infecciones por Pasteurella/veterinaria , Alveolos Pulmonares/citología , Infecciones del Sistema Respiratorio/veterinaria , Animales , Bovinos , Enfermedades de los Bovinos/fisiopatología , Técnicas In Vitro , Mediciones Luminiscentes , Luminol , Pasteurella/aislamiento & purificación , Infecciones por Pasteurella/fisiopatología , Infecciones del Sistema Respiratorio/fisiopatología , Irrigación Terapéutica
17.
Am J Vet Res ; 50(3): 329-34, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2648902

RESUMEN

Live Pasteurella haemolytica biotype A, serotype 1 isolates (n = 3) and Escherichia coli K-12, strain W3110, were reacted with bovine pulmonary lavage cell (PLC) suspensions. The comparative effects of the different bacteria on the functional and metabolic activity of alveolar macrophages (AMO) in the PLC suspensions were assessed simultaneously by use of 51Cr release, luminol-dependent chemiluminescence (LDCL), and AMO bactericidal assays. The bovine PLC responded differently to E coli, than to the 3 P haemolytica isolates in each of the 3 experimental test systems; however, responses to each of the P haemolytica isolates were not found to be significantly different. Unopsonized live P haemolytica cells adversely affected the functional and metabolic response of PLC, whereas there was no evidence of a cytotoxic (cytocidal) influence of E coli. A difference in 51Cr release for reaction mixtures containing E coli and P haemolytica was not detected at zero time; however, at each subsequent time, reaction mixtures phagocytically stimulated with P haemolytica had significantly increased amount of 51Cr release (P less than 0.05), compared with those mixtures containing E coli. Bovine AMO in the PLC suspensions were able to effectively kill E coli in vitro, but were unable to prevent survival and subsequent growth of P haemolytica. The luminol-dependent chemiluminescence profiles for reaction mixtures phagocytically stimulated with E coli provided evidence of sustained production of oxygen radicals with antimicrobial capabilities by bovine AMO in the PLC. Production of these highly reactive antimicrobial oxidants appeared initially in cultures containing P haemolytica but, subsequently, their production declined precipitously and ceased altogether.


Asunto(s)
Líquido del Lavado Bronquioalveolar/citología , Macrófagos/inmunología , Pasteurella/inmunología , Fagocitosis , Animales , Bovinos , Escherichia coli/inmunología , Mediciones Luminiscentes , Macrófagos/metabolismo
18.
Am J Vet Res ; 51(8): 1161-6, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2201228

RESUMEN

A commercially available microbiological identification system and DNA:DNA hybridization were used to determine relationships between and within serovars 1-13 of Pasteurella haemolytica, and between P haemolytica and P multocida and 4 species of Actinobacillus. All serovars of P haemolytica that belonged to biovar A were related with mean DNA homology of 78%, whereas all serovars of P haemolytica that belonged to biovar T were related to each other with mean DNA homology of 90%. The DNA:DNA hybridization between strains of biovars A and T ranged from 3 to 13%, indicating little or no genetic relationship between the 2 biovars of P haemolytica. The DNA homology between all serovars of P haemolytica and other species of non-P haemolytica bacteria tested (P multocida and actinobacilli) was less than 14%, suggestive of essentially no genetic relationship of P haemolytica with the ATCC reference strains of the genus Pasteurella or the genus Actinobacillus. Enzymatic differences were observed between P haemolytica and the other non-P haemolytica bacteria tested; however, the microbiological identification system that uses enzymatic reactions could not distinguish among biovars of P haemolytica. Results of this research support other data that suggest that biovars A and T of P haemolytica should be classified as separate species, but do not support the inclusion of either biovar A or T within the genus Actinobacillus.


Asunto(s)
Técnicas de Tipificación Bacteriana , Secuencia de Bases , ADN Bacteriano/aislamiento & purificación , Pasteurella/clasificación , Homología de Secuencia de Ácido Nucleico , Fosfatasa Ácida/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Pasteurella/enzimología , Especificidad de la Especie , Terminología como Asunto
19.
Am J Vet Res ; 50(2): 221-5, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2719384

RESUMEN

An in vitro bactericidal assay that used bovine heparinized blood was investigated for its usefulness in detecting differences in the bactericidal immunity of calves against Pasteurella haemolytica serotype 1 (Ph1). Greater than 90% of killing occurred within 30 minutes. The substitution of fetal calf serum for autologous calf plasma caused loss of bactericidal activity of the blood. Decomplemented calf serum also was low in bactericidal activity. The blood bactericidal assay appears to be opsonin antibody-dependent and complement-dependent. The coefficient of variation (CV) that can be expected with this assay was established by use of a group of 8 calves; within-day CV maximum was 0.9, and between-day CV maximum was 2.1. The blood bactericidal assay was used to evaluate 30 calves under typical market stress from 4 farms in eastern Tennessee. All calves had decreased bactericidal activity, as they moved into a feedyard in Texas. The bactericidal activity was reduced among sick calves, based on the severity of clinical signs. Morbidity was highest during the first 14 days in the feedlot. During this period, healthy calves had a decreased bactericidal index (BI) of 4 points, and calves with clinical signs of bovine respiratory tract disease for 3 days had a decreased BI of 8 points. The average reduction in the BI of calves with clinical signs of bovine respiratory tract disease for 6 or more days was 14 points.


Asunto(s)
Actividad Bactericida de la Sangre , Enfermedades de los Bovinos/inmunología , Bovinos/inmunología , Pasteurella/inmunología , Infecciones del Sistema Respiratorio/veterinaria , Animales , Anticuerpos Antibacterianos/inmunología , Proteínas del Sistema Complemento/inmunología , Femenino , Masculino , Proteínas Opsoninas/inmunología , Infecciones por Pasteurella/inmunología , Infecciones por Pasteurella/veterinaria , Infecciones del Sistema Respiratorio/inmunología
20.
Am J Vet Res ; 52(11): 1842-7, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1785726

RESUMEN

Classical hemolytic complement (C) of calves was analyzed during a protocol designed to imitate the usual market handling of feeder calves from the southeastern United States. Serum C concentrations of the calves (n = 100 x 4 years) were evaluated on their farm of origin, on arrival at an auction market, on arrival at a feedyard, and during their first 4 weeks in the feedyard. Complement concentrations (measured in CH50 units) were typically lowest at the farm of origin and highest when the calves entered the auction market 28 to 133 days later. Serum C concentrations decreased after the calves encountered the severe stresses of being in the auction market for 7 days, 24-hour truck transport (1,932 km) to the feedyard, and the first 7 days in the feedyard. The C concentrations recovered after 21 to 28 days in the feedyard. Steers had significantly (P less than or equal to 0.05) lower C concentrations than did heifers in 3 of 4 years at the farm of origin, and in 2 of 4 years at the auction market. Morbid calves had significantly (P less than or equal to 0.05) lower C values than did healthy calves on day 7 in the feedyard in 3 of 4 years. There were significant differences in C concentrations of calves from different farms of origin in each of the 4 years. There was no significant difference in C concentrations of calves that were vaccinated vs those not vaccinated with Pasteurella haemolytica.


Asunto(s)
Enfermedades de los Bovinos/inmunología , Proteínas del Sistema Complemento/análisis , Estrés Fisiológico/veterinaria , Animales , Vacunas Bacterianas , Bovinos , Femenino , Masculino , Mannheimia haemolytica/inmunología , Infecciones del Sistema Respiratorio/inmunología , Infecciones del Sistema Respiratorio/veterinaria , Factores Sexuales , Estrés Fisiológico/inmunología , Vacunación/veterinaria
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