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1.
J Dairy Sci ; 107(3): 1734-1750, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37806632

RESUMEN

This study aimed to characterize the development of systemic and colon tissue resident B and γδ T cells in newborn calves from birth until weaning. At birth, calves have limited capacity to initiate immune responses, and the immune system gradually matures over time. Gamma delta (γδ) T cells are an important lymphocyte subset in neonatal calves that confer protection and promote immune tolerance. A total of 36 newborn calves were enrolled in a longitudinal study to characterize how systemic and colon tissue resident B and γδ T cells develop from birth until weaning. Blood and colon biopsy samples were collected on d 2, 28, and 42 to determine the proportions of various B and γδ T cell subsets by flow cytometry. We classified γδ T cells into different functional subsets according to the level of expression intensity of the coreceptors WC1.1 (effector function) and WC1.2 (regulatory function). Furthermore, naive B cells were classified based on the expression IgM receptor, and activation state was determined based on expression of CD21 and CD32, 2 receptors with opposing signals involved in B cell activation in early life. Additional colon biopsy samples were used for 16S sequencing, and microbial diversity data are reported. At birth, γδ T cells were the most abundant lymphocyte population in blood, accounting for 58.5% of the lymphocyte pool, after which the proportions of these cells declined to 38.2% after weaning. The proportion of γδ T cells expressing WC1.1 decreased by 50% from d 2 to d 28, whereas no change was observed in the expression of WC1.2. In the colon, there was a 50% increase of γδ T cells after weaning and the proportion of WC1.2+ γδ T cells doubled from d 28 to 42. The proportion of IgM+ B lymphocytes in blood increased from 23.6% at birth to 30% after weaning, were the proportion of B cells expressing CD21 increased by 25%, while the proportion of B cells expressing CD32 decreased by 30%. While no changes were observed for the overall proportion of IgM+ B lymphocytes in the colon, there was a 6-fold increase in the proportion of CD21+ B cells from pre- (d 28) to postweaning (d 42). Microbial diversity increased from d 2 of life to 28 and declined abruptly after weaning. The reduction in microbial diversity during weaning was negatively correlated with the increase in all γδ T cell subsets and CD21+ B cells. These data suggest that developmental adaptations after birth coordinate expansion of γδ T cells to provide early systemic protection, as well as to steer immune tolerance, while B cells mature over time. Additionally, the increase of colonic γδ T cells on d 42 suggests a protective role of these cells during weaning.


Asunto(s)
Linfocitos B , Mucosa Intestinal , Animales , Bovinos , Masculino , Destete , Estudios Longitudinales , Linfocitos T , Inmunoglobulina M
2.
J Dairy Sci ; 106(4): 2857-2865, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36797191

RESUMEN

In cattle, maternal immunoglobulins are transferred through colostrum to provide passive immunity to the neonatal calf once they are absorbed into circulation. Cows can be assessed for antibody- and cell-mediated immune responses (AMIR and CMIR, respectively), and through estimated breeding values (EBV) and genomic parent averages (GPA), cows can be classified as having high, average, or low immune response (IR). The objective of this study was to identify associations of colostral IgG concentrations with IR in dairy cows. High IR dairy cows identified by GPA or EBV were hypothesized to produce higher colostral IgG concentrations than cows with average or low IR. Colostrum was collected from Holstein dairy cows from 3 large commercial herds (n = 590) in the United States and 1 research herd at the Ontario Dairy Research Centre (n = 275) in Canada. For the US herds, IR GPA were available through genotyping. For the Canadian herd, IR EBV were available through phenotyping and pedigree information. Colostral IgG concentrations were measured by radial immunodiffusion and analyzed using general linear models in SAS. Based on a prediction equation, cows in US herds with a CMIR GPA of 1 would have colostral IgG concentrations 6.3 g/L higher on average than cows with a CMIR GPA of 0. High CMIR cows produced statistically greater colostral IgG concentrations (least squares mean ± standard error of the mean, 107.5 ± 7.7 g/L) than low CMIR cows (91.4 ± 7.1 g/L), with intermediate values for average CMIR cows (105.1 ± 5.6 g/L). No differences were found among AMIR categories in US cows. The Canadian herd showed a trend for cows with high CMIR EBV (continuous variable) to produce greater colostral IgG. No differences were observed among high, average, and low AMIR EBV classifications in Canadian cows. The findings suggest that selective breeding of Holstein cows to enhance CMIR could contribute to higher-quality colostrum in succeeding generations.


Asunto(s)
Calostro , Inmunoglobulina G , Embarazo , Femenino , Bovinos , Animales , Lactancia/fisiología , Inmunidad Celular , Ontario
3.
Clin Psychol Rev ; 100: 102251, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36716584

RESUMEN

This systematic review aimed to determine whether the use of specific behaviour change technique (BCT) groups are associated with greater effectiveness for psychosocial interventions delivered to family and close friends (FCFs) impacted by addiction. A systematic search of peer-reviewed and grey literature published until August 2021 identified 32 studies in 38 articles. An established BCT taxonomy (93 BCTs clustered into 16 groups) was adapted (inclusion of seven additional BCT groups) and applied to 57 interventions. The meta-analyses indicated that some, but not all, FCF outcomes were improved by the exclusion of BCTs within several groups (Reward and Threat, Scheduled Consequences, Confrontation of the Addicted Person to Engage in Treatment, and Goals and Planning) and inclusion of BCTs within the Restoring a Balanced Lifestyle group. Addicted person outcomes were improved by the inclusion of some BCTs within several groups (Repetition and Substitution, Reward and Threat, Scheduled Consequences, and Restoring a Balanced Lifestyle). Relationship functioning outcomes were improved by the inclusion of BCTs within the Confrontation of the Addicted Person to Engage in Treatment group. Future research involving the development and evaluation of numerous interventions or comprehensive multi-component interventions that can address the various needs of FCFs, without counteracting them, is required.


Asunto(s)
Terapia Conductista , Amigos , Humanos , Terapia Conductista/métodos , Recompensa
5.
BMJ Open ; 7(3): e013490, 2017 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-28255094

RESUMEN

INTRODUCTION: The primary purpose of this study is to evaluate the relative effectiveness of 2 of the best developed and most promising forms of therapy for problem gambling, namely face-to-face motivational interviewing (MI) combined with a self-instruction booklet (W) and follow-up telephone booster sessions (B; MI+W+B) and face-to-face cognitive-behavioural therapy (CBT). METHODS AND ANALYSIS: This project is a single-blind pragmatic randomised clinical trial of 2 interventions, with and without the addition of relapse-prevention text messages. Trial assessments take place pretreatment, at 3 and 12 months. A total of 300 participants will be recruited through a community treatment agency that provides services across New Zealand and randomised to up to 10 face-to-face sessions of CBT or 1 face-to-face session of MI+W+up to 5 B. Participants will also be randomised to 9 months of postcare text messaging. Eligibility criteria include a self-perception of having a current gambling problem and a willingness to participate in all components of the study (eg, read workbook). The statistical analysis will use an intent-to-treat approach. Primary outcome measures are days spent gambling and amount of money spent per day gambling in the prior month. Secondary outcome measures include problem gambling severity, gambling urges, gambling cognitions, mood, alcohol, drug use, tobacco, psychological distress, quality of life, health status and direct and indirect costs associated with treatment. ETHICS AND DISSEMINATION: The research methods to be used in this study have been approved by the Ministry of Health, Health and Disability Ethics Committees (HDEC) 15/CEN/99. The investigators will provide annual reports to the HDEC and report any adverse events to this committee. Amendments will also be submitted to this committee. The results of this trial will be submitted for publication in peer-reviewed journals and as a report to the funding body. Additionally, the results will be presented at national and international conferences. TRIAL REGISTRATION NUMBER: ACTRN12615000637549.


Asunto(s)
Conducta Adictiva/terapia , Terapia Cognitivo-Conductual/métodos , Juego de Azar/terapia , Entrevista Motivacional , Folletos , Envío de Mensajes de Texto , Femenino , Humanos , Masculino , Proyectos de Investigación , Método Simple Ciego , Teléfono
6.
J Dairy Sci ; 99(3): 2358-2363, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26774725

RESUMEN

The objective of this study was to evaluate IgG and ß-lactoglobulin (ß-LG) concentrations in colostrum and milk of Canadian Holsteins (n=108) classified as high (H), average (A), or low (L) for antibody-mediated (AMIR) or cell-mediated immune responses (CMIR) based on estimated breeding values. It was hypothesized that H-AMIR and H-CMIR cows produce colostrum (first milking) and milk (d 5 postcalving) with higher concentrations of IgG and ß-LG. Data for IgG and ß-LG in colostrum and milk were analyzed independently using mixed linear models. Least squares means were compared using Tukey's test. Cows classified as H-AMIR had higher IgG and ß-LG concentrations in colostrum compared with A- and L-AMIR cows; 84% of H-AMIR, 69% of A-AMIR, and 68% of L-AMIR cows had over 5,000 mg/dL IgG in colostrum. No differences in IgG and ß-LG concentrations in colostrum were noted among cows ranked on CMIR or in milk of cows ranked on AMIR. ß-Lactoglobulin and IgG concentrations were positively correlated in colostrum. Breeding cows for H-AMIR status may reduce failure of passive transfer of IgG in their calves; ß-LG may play a role in bovine immune defenses. Colostrum from H-AMIR cows may serve as a more economical feedstock source for manufacturing natural health products.


Asunto(s)
Bovinos/inmunología , Calostro/química , Inmunoglobulina G/metabolismo , Lactoglobulinas/metabolismo , Leche/química , Animales , Bovinos/metabolismo , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Inmunodifusión/veterinaria , Lactancia
7.
Res Vet Sci ; 103: 170-5, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26679813

RESUMEN

Lactobacilli are commensal microbes that reside in the intestines of several species, including chickens. Structural constituents of lactobacilli are able to stimulate the host immune system. Macrophages are crucial players in both innate and adaptive immune systems. Here, we investigated the effects of Lactobacillus acidophilus, Lactobacillus reuteri, Lactobacillus salivarius and their cell-free culture supernatants on the pro-inflammatory gene expression profile, nitric oxide (NO) production and phagocytosis by chicken macrophages. Substantial differences were found among Lactobacillus strains in their capacity to induce pro-inflammatory cytokines. L. acidophilus only up-regulated interferon (IFN)-γ, while L. reuteri and L. salivarius up-regulated interleukin (IL)-1ß, IL-6, IL-8 and IL-12 expression. Supernatant of L. salivarius up-regulated IL-1ß, IL-8 and IFN-γ expression, while the other cell-free supernatants did not induce significant changes. Moreover, L. reuteri and L. salivarius increased macrophage phagocytosis, but all cell-free supernatants increased macrophage NO production and did not change phagocytosis activity.


Asunto(s)
Pollos/inmunología , Pollos/microbiología , Lactobacillus/fisiología , Macrófagos/inmunología , Animales , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Citocinas/genética , Citocinas/metabolismo , Regulación de la Expresión Génica , Óxido Nítrico/metabolismo , Fagocitosis , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Análisis de Secuencia de ADN/veterinaria , Simbiosis
8.
J Vet Intern Med ; 28(2): 599-602, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24495235

RESUMEN

BACKGROUND: Rapid identification of sepsis enables prompt administration of antibiotics and is essential to improve patient survival. Procalcitonin (PCT) is a biomarker used to diagnose sepsis in people. Commercial assays to measure canine PCT peptide have not been validated. OBJECTIVE: To investigate the validity of a commercially available enzyme-linked immunosorbent assay (ELISA) marketed for the measurement of canine PCT. ANIMALS: Three dogs with sepsis, 1 healthy dog, 1 dog with thyroid carcinoma. METHODS: Experimental study. The ELISA's ability to detect recombinant and native canine PCT was investigated and intra-assay and interassay coefficients of variability were calculated. Assay validation including mass spectrometry of the kit standard solution was performed. RESULTS: The ELISA did not consistently detect recombinant canine PCT. Thyroid lysate yielded a positive ELISA signal. Intra-assay variability ranged from 18.9 to 77.4%, while interassay variability ranged from 56.1 to 79.5%. Mass spectrometry of the standard solution provided with the evaluated ELISA kit did not indicate presence of PCT. CONCLUSIONS AND CLINICAL IMPORTANCE: The results of this investigation do not support the use of this ELISA for the detection of PCT in dogs.


Asunto(s)
Calcitonina/sangre , Ensayo de Inmunoadsorción Enzimática/veterinaria , Precursores de Proteínas/sangre , Animales , Biomarcadores/sangre , Enfermedades de los Perros/sangre , Perros/sangre , Reproducibilidad de los Resultados , Sepsis/sangre , Sepsis/veterinaria , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/veterinaria
9.
Prev Vet Med ; 113(2): 231-40, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-24269039

RESUMEN

Calfhood disease is an important problem on many dairy operations that can have substantial effects on heifer survival and productivity, and has economic and welfare impacts. Neonatal calf diarrhea (NCD) and bovine respiratory disease (BRD) are the most common causes of morbidity and mortality in young dairy cattle. The objective of this observational study was to investigate factors associated with the risks of morbidity and mortality, and with growth, in commercial dairy heifers calves. A total of 2874 heifer calves from 19 commercial dairy farms in Minnesota and Ontario were enrolled at 1-7 days of age and followed for approximately 3 months. Using cut-points of serum total protein of 5.2 and 5.7 g/dl, the incidences of failure of transfer of passive immunity (FTPI) were 11 and 32%, respectively. A cut-point of 5.7 g/dl was the most predictive of BRD before 5 weeks of age (sensitivity=40%, specificity=69%). The positive predictive value was poor (PPV=18%), but the negative predictive value was good (NPV=87%). A cut-point of 5.2g/dl was most predictive of death before 5 weeks of age (sensitivity=27%, specificity=89%, PPV=5%, NPV=98%). Serum total protein during the first week of life was a poor predictor of NCD. Over 23% of calves were treated for diarrhea. Risk factors were weight at enrollment, other diseases before 2 weeks of age, and an interaction between season of birth and herd-level incidence of NCD. Almost 22% of calves were treated at least once for BRD. Factors associated with an increased risk of BRD included herd-level incidence of BRD, season of birth, navel dipping, other diseases before 2 weeks of age, failure of transfer of passive immunity, and manual control of temperature in pre-weaning housing. Administration of supplemental antibody products at birth was associated with a reduced incidence of BRD. Overall mortality was 3.5%. Risk of mortality was increased by treatment for BRD and other diseases. The mean average weight gain was 0.95 kg/day (range: 0.11-1.62 kg/day; SD=0.2). Twinning status, FTP, treatment for NCD or other diseases, and month of birth influenced body weight. This study illustrated relationships among various diseases, mortality, and growth. Furthermore, it demonstrated the importance of colostrum for protection against BRD and improved growth performance, while bringing into question the optimal method of determining failure of transfer of passive immunity.


Asunto(s)
Enfermedades de los Bovinos/inmunología , Diarrea/veterinaria , Inmunización Pasiva/veterinaria , Enfermedades Respiratorias/veterinaria , Crianza de Animales Domésticos , Animales , Animales Recién Nacidos , Proteínas Sanguíneas/análisis , Bovinos , Enfermedades de los Bovinos/epidemiología , Diarrea/epidemiología , Diarrea/inmunología , Femenino , Incidencia , Modelos Logísticos , Minnesota/epidemiología , Ontario/epidemiología , Valor Predictivo de las Pruebas , Prevalencia , Enfermedades Respiratorias/epidemiología , Enfermedades Respiratorias/inmunología , Factores de Riesgo , Estaciones del Año , Sensibilidad y Especificidad
10.
J Dairy Sci ; 95(11): 6731-9, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22959931

RESUMEN

Bovine respiratory disease (BRD) is one of the most common infectious causes of morbidity and mortality in young dairy cattle. The objective of this randomized clinical trial was to determine the effectiveness of 1 or 2 doses of a 5-way, modified-live viral vaccine, administered to heifer calves before weaning to aid in the prevention of BRD. The hypotheses were that vaccination would reduce the incidence of BRD and mortality, and that 2 doses would be more effective than 1. A total of 2,874 heifer calves from 19 commercial dairy farms in Minnesota and Ontario were enrolled at 1 to 7d of age and were followed until 3 mo of age. Calves were randomly assigned to receive a commercial, intramuscular, modified-live vaccine against bovine viral diarrhea virus types 1 and 2, bovine respiratory syncytial virus, bovine herpesvirus type 1, and parainfluenza virus type 3 at 15 to 21 d of age (2 wk only), 35 to 42 d (5 wk only), both 2 and 5 wk, or sterile saline at both times (unvaccinated controls). The incidence of failure of passive transfer was 11 or 32%, using cut-points of serum total protein of 5.2 and 5.7 g/dL, respectively. Overall, 22% of calves were treated at least once for BRD. The incidence risk of naturally occurring BRD was 7.7% before 2 wk of age, 8.0% between 2 and 5 wk, and 9.5% between 5 wk and 3 mo of age, and was not different between vaccination groups. Overall mortality throughout the 3-mo study period was 3.5%. Mortality was 1.6% before 2 wk of age, 0.5% between 2 and 5 wk, and 1.2% between 5 wk and 3 mo of age. The risk of mortality was not affected by vaccination. Mean average daily gain of 1.07 kg/d from 5 wk to 3 mo of age was not different between vaccine groups. In this population of commercial, home-raised calves, with an overall low incidence of failure of passive transfer, intramuscular vaccination with a multivalent, modified live viral vaccine at 2 or 5 wk of age or both was not associated with a decreased risk of BRD or mortality, or with growth until 3 mo of age. Reasons for these findings may include interference by maternal antibodies, unresponsiveness of the neonatal immune system, timing of immunity relative to pathogen exposure, disease caused by pathogens other than the viruses in the vaccine, or herd immunity. However, in populations with higher incidence of failure of passive transfer or risk of BRD, calves with low levels of specific antibodies may respond differently to vaccination.


Asunto(s)
Complejo Respiratorio Bovino/prevención & control , Vacunas Virales/uso terapéutico , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Animales Recién Nacidos/inmunología , Animales Recién Nacidos/virología , Complejo Respiratorio Bovino/epidemiología , Complejo Respiratorio Bovino/inmunología , Complejo Respiratorio Bovino/mortalidad , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/prevención & control , Virus de la Diarrea Viral Bovina Tipo 1/inmunología , Virus de la Diarrea Viral Bovina Tipo 2/inmunología , Femenino , Infecciones por Herpesviridae/inmunología , Infecciones por Herpesviridae/prevención & control , Herpesvirus Bovino 1/inmunología , Incidencia , Virus de la Parainfluenza 3 Bovina/inmunología , Infecciones por Virus Sincitial Respiratorio/prevención & control , Virus Sincitial Respiratorio Bovino/inmunología , Infecciones por Respirovirus/prevención & control , Infecciones por Respirovirus/veterinaria
11.
Psychol Med ; 42(11): 2433-44, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22717172

RESUMEN

BACKGROUND: When gambling opportunities are made available to the public in a given jurisdiction, some individuals participate occasionally and others more frequently. Among frequent gamblers, some individuals develop problematic involvement and some do not. This study addresses the association among demographic and social risk factors, frequency of gambling and gambling disorders. METHOD: Data from an adult community sample (n=1372) were used to identify risk factors for higher-frequency gambling and disordered gambling involvement. RESULTS: Individuals with higher intelligence, older individuals and more religious individuals were less frequent gamblers. Males, single individuals and those exposed to gambling environments (friends and family who gamble) and those who started to gamble at a younger age were more frequent gamblers. Excitement-seeking personality traits were also higher among more frequent gamblers. A different set of risk factors was associated with the likelihood of gambling disorder among these higher-frequency gamblers. These variables included mental health indicators, childhood maltreatment and parental gambling involvement. Among higher-frequency gamblers, individuals who smoke cigarettes, those with a diagnosis of alcohol or drug dependence or obsessive-compulsive disorder, those with higher anxiety or depression and those with higher impulsivity and antisocial personality traits were more likely to report gambling-related problems. These individuals were also more likely to report gambling on electronic gambling machines (e.g. slot machines). CONCLUSIONS: These data suggest a model in which higher-frequency gambling, particularly with electronic gambling machines, when combined with any type of emotional vulnerability increased the likelihood of gambling disorder.


Asunto(s)
Juego de Azar/epidemiología , Adulto , Alberta/epidemiología , Comorbilidad , Femenino , Juego de Azar/etiología , Juego de Azar/psicología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Sexuales
12.
Biotechnol Appl Biochem ; 58(3): 198-202, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21679244

RESUMEN

The aim of this study was to incorporate antigens from Mannheimia haemolytica culture supernatant, and an immune modulatory molecule, recombinant bovine C3d (rBoC3d), into immune stimulating complexes (ISCOMs) using neutravidin-biotin interaction. Biotinylated ISCOM matrix was generated using a commercial kit. The biotinylated ISCOM matrix was incubated with neutravidin and then centrifuged in a sucrose density gradient. The rBoC3d was expressed as an in vivo biotinylated protein and with a c-Myc tag (EQKLISEEDL) engineered to facilitate detection. The neutravidin-coated ISCOM matrix was incubated with biotinylated antigens from M. haemolytica culture supernatants and rBoC3d. To test the association among the neutravidin-coated ISCOM matrix, biotinylated antigens and rBoC3d, an analytical sucrose density gradient (10-40%, w/w) was performed. The experimental formulations were run in SDS-PAGE gels under reducing conditions. For Western immunoblot analysis, polyclonal bovine antiavidin, monoclonal anti-c-Myc, monoclonal antileukotoxin, and anti-GS60 antibodies were used to detect the presence of neutravidin, rBoC3d, leukotoxin, and GS60 antigens, respectively. By taking advantage of the biotin-neutravidin interaction, not only leukotoxin but also the recombinant immunomodulatory molecule, rBoC3d, was incorporated into ISCOM particles.


Asunto(s)
Antígenos Bacterianos/inmunología , Avidina/metabolismo , Biotina/metabolismo , Complemento C3d/inmunología , Medios de Cultivo/química , ISCOMs/inmunología , Mannheimia haemolytica/inmunología , Animales , Antígenos Bacterianos/aislamiento & purificación , Biotecnología , Bovinos , Mannheimia haemolytica/citología , Proteínas Recombinantes/inmunología
13.
Vet Immunol Immunopathol ; 128(1-3): 192-8, 2009 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-19046777

RESUMEN

Recognition of the mucosal portal of entry for many infectious diseases and of the relevance of mucosal immune response to protection has encouraged the development of vaccines administered by mucosal routes, principally oral and intranasal, for stimulation of intestinal and nasopharyngeal lymphoid tissues respectively. The oral route is problematic in cattle and other ruminants where antigen degradation in the rumen is likely, prior to transit to the intestine. On the other hand, rumination can be exploited for exposure of nasopharyngeal tissues during cudding if vaccine antigen is expressed by a fibrous feed like alfalfa. An increase in anti-leukotoxin (Lkt) IgA was demonstrated in nasal secretions of calves following feeding of alfalfa expressing a truncated Lkt50 from Mannheimia haemolytica, and there is evidence suggesting that such vaccination may protect against experimentally induced pneumonia. Intranasal vaccination is an alternative approach for use in pre-ruminating calves. Intranasal administration of ISCOMs carrying soluble antigens of M. haemolytica, including native Lkt, induced Lkt specific IgA in nasal secretions after vaccination at 4 and 6 weeks of age. Subcutaneous (s.c.) administration of the same vaccine induced Lkt specific IgG in both serum and nasal secretions, whereas s.c. administration of a commercial M. haemolytica vaccine did not. Regardless of the vaccination strategy employed it is difficult to assess the immunogenicity of mucosally administered vaccines because production of secreted antibodies tends to be transient, and they do not persist on the mucosal surface in the absence of ongoing antigenic stimulation. An additional challenge is demonstration of vaccine efficacy in response to experimental infection. Protection of the mucosally vaccinated animal will most probably result from recall response, which may not amplify sufficiently to counter the effects of experimental pulmonary delivery of a large bolus of virulent bacteria, even though the response would suffice over the more prolonged and gradual infection that occurs in natural induction of pneumonia.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Vacunación/veterinaria , Vacunas/administración & dosificación , Vacunas/inmunología , Administración Oral , Animales , Animales Recién Nacidos , Antígenos/metabolismo , Bovinos , Rumen/metabolismo
14.
Anim Health Res Rev ; 8(2): 117-28, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18218156

RESUMEN

Mannheimia haemolytica is the principal bacterium isolated from respiratory disease in feedlot cattle and is a significant component of enzootic pneumonia in all neonatal calves. A commensal of the nasopharynx, M. haemolytica is an opportunist, gaining access to the lungs when host defenses are compromised by stress or infection with respiratory viruses or mycoplasma. Although several serotypes act as commensals, A1 and A6 are the most frequent isolates from pneumonic lungs. Potential virulence factors include adhesin, capsular polysaccharide, fimbriae, iron-regulated outer membrane proteins, leukotoxin (Lkt), lipopolysaccharide (LPS), lipoproteins, neuraminidase, sialoglycoprotease and transferrin-binding proteins. Of these, Lkt is pivotal in induction of pneumonia. Lkt-mediated infiltration and destruction of neutrophils and other leukocytes impairs bacterial clearance and contributes to development of fibrinous pneumonia. LPS may act synergistically with Lkt, enhancing its effects and contributing endotoxic activity. Antibiotics are employed extensively in the feedlot industry, both prophylactically and therapeutically, but their efficacy varies because of inconsistencies in diagnosis and treatment regimes and development of antibiotic resistance. Vaccines have been used for many decades, even though traditional bacterins failed to demonstrate protection and their use often enhanced disease in vaccinated animals. Modern vaccines use culture supernatants containing Lkt and other soluble antigens, or bacterial extracts, alone or combined with bacterins. These vaccines have 50-70% efficacy in prevention of M. haemolytica pneumonia. Effective control of M. haemolytica pneumonia is likely to require a combination of more definitive diagnosis, efficacious vaccines, therapeutic intervention and improved management practices.


Asunto(s)
Vacunas Bacterianas/inmunología , Complejo Respiratorio Bovino/epidemiología , Complejo Respiratorio Bovino/microbiología , Mannheimia haemolytica/patogenicidad , Crianza de Animales Domésticos/métodos , Animales , Animales Recién Nacidos , Complejo Respiratorio Bovino/prevención & control , Bovinos , Exotoxinas/inmunología , Neumonía Enzoótica de los Becerros/epidemiología , Neumonía Enzoótica de los Becerros/microbiología , Neumonía Enzoótica de los Becerros/prevención & control , Factores de Riesgo , Serotipificación/veterinaria
15.
J Clin Microbiol ; 39(8): 2807-13, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11473996

RESUMEN

Because of their similarities to infants in mucosal immune responses and their susceptibility to human rotavirus (HRV) diarrhea, gnotobiotic pigs provide a useful model for rotaviral disease. In this study, we performed quantitative enzyme-linked immunospot (ELISPOT) assays to measure local and systemic isotype-specific antibody-secreting cell (ASC) responses to individual structural (VP4, VP6, and VP7) and nonstructural (NSP3 and NSP4) proteins of Wa HRV. The Spodoptera frugiperda cells expressing each recombinant baculovirus HRV protein were formalin fixed and used as antigen for ELISPOT assays. Neonatal gnotobiotic pigs were orally inoculated once with virulent Wa (WaV) or three times with attenuated Wa (WaA) HRV or mock inoculated (Mock) and then were challenged with virulent Wa (WaV/PC) 28 days after the first inoculation. The ASCs from intestinal and systemic lymphoid tissues of pigs from each group were quantitated by ELISPOT assay at the day of challenge, at postinoculation day 28 (WaV, WaA, and Mock) or at postchallenge day (PCD) 7 (WaV+WaV/PC, WaA+WaV/PC, and Mock+WaV/PC). In all virus-inoculated pigs, regardless of the inoculum, lymphoid tissue, or isotype, VP6 induced the highest numbers of ASCs, followed by VP4; ASCs specific for VP7, NSP3, and NSP4 were less numerous. At challenge, total HRV- and HRV protein-specific immunoglobulin A (IgA) and IgG ASCs in intestinal lymphoid tissues were significantly greater in WaV- than in WaA-inoculated pigs, and WaV pigs were fully protected against diarrhea postchallenge, whereas the WaA pigs were partially protected. At PCD 7, there were no significant differences in ASC numbers for any HRV proteins between the WaV+WaV/PC and WaA+WaV/PC groups.


Asunto(s)
Células Productoras de Anticuerpos/inmunología , Vida Libre de Gérmenes , Infecciones por Rotavirus/inmunología , Rotavirus/inmunología , Porcinos , Proteínas Virales/inmunología , Animales , Animales Recién Nacidos , Modelos Animales de Enfermedad , Humanos , Hibridomas , Rotavirus/patogenicidad , Infecciones por Rotavirus/virología , Esparcimiento de Virus
16.
J Consult Clin Psychol ; 69(1): 50-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11302277

RESUMEN

Two brief treatments for problem gambling were compared with a waiting-list control in a randomized trial. Eighty-four percent of participants (N = 102) reported a significant reduction in gambling over a 12-month follow-up period. Participants who received a motivational enhancement telephone intervention and a self-help workbook in the mail, but not those who received the workbook only, had better outcomes than participants in a 1-month waiting-list control. Participants who received the motivational interview and workbook showed better outcomes than those receiving the workbook only at 3- and 6-month follow-ups. At the 12-month follow-up, the advantage of the motivational interview and workbook condition was found only for participants with less severe gambling problems. Overall, these results support the effectiveness of a brief telephone and mail-based treatment for problem gambling.


Asunto(s)
Juego de Azar/psicología , Motivación , Psicoterapia Breve/métodos , Autocuidado/psicología , Adulto , Canadá , Humanos , Persona de Mediana Edad , Resultado del Tratamiento
17.
Addict Behav ; 26(1): 121-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11196286

RESUMEN

Recovered problem gamblers (N = 37) described the processes used in overcoming their gambling problem using a modified version of the Processes of Change Questionnaire (J. O. Prochaska, W. F. Velicer, C. C. DiClemente, & J. S. Fava, 1988). The most frequently used processes were cognitive-experiential in nature and included self-reevaluation, environmental reevaluation, dramatic relief, and self-liberation. The least-used processes were reinforcement management and social liberation. Individuals who had sought gambling treatment reported greater use of most processes, in particular cognitive-experiential ones, compared with self-changers. The processes reported by participants were similar to those elicited through open-ended questions, but the results for problem gamblers differ from results of studies of other types of behavior change.


Asunto(s)
Juego de Azar/psicología , Motivación , Adulto , Cognición , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Autoimagen , Conducta Social , Encuestas y Cuestionarios
18.
J Subst Abuse ; 13(4): 443-58, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11775075

RESUMEN

PURPOSE: Rates of smoking are much higher among persons with alcohol problems and a history of depressive illness than persons without those disorders. Drug use in general may be motivated by outcome expectancies such as negative affective reduction and relaxation. Persons with a history of depression may smoke as a means of mood management. The role of outcome expectancies and major depression in maintaining smoking behavior in a high-risk group of smokers, such as recovering alcoholics, has not been thoroughly examined. METHODS: Using a cross-sectional design, 161 abstinent alcohol-dependent men and women who smoked were administered the Inventory to Diagnose Depression (IDD), a self-report instrument for assessing current and lifetime depression according to DSM-IV criteria, and measures of alcohol dependence, nicotine dependence, smoking motives, and situation-defined temptations to smoke. RESULTS: As expected, smoking motives and temptations were moderated by history of depression. Alcoholics with a history of depression were more likely to smoke with the expectancy of negative affect reduction than those with no prior major depression. Using multiple regression, negative affective reduction, addiction, and severity of past depression were the strongest predictors of current temptations to smoke. IMPLICATIONS: These results suggest that individuals with a combined history of alcoholism and major depression are at a high risk to use smoking as a means of mood enhancement.


Asunto(s)
Alcoholismo/psicología , Trastorno Depresivo/psicología , Fumar/psicología , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino , Distribución por Sexo , Cese del Hábito de Fumar/psicología , Templanza , Resultado del Tratamiento
19.
J Virol ; 74(19): 8843-53, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10982326

RESUMEN

We investigated the immunogenicity of recombinant double-layered rotavirus-like particle (2/6-VLPs) vaccines derived from simian SA11 or human (VP6) Wa and bovine RF (VP2) rotavirus strains. The 2/6-VLPs were administered to gnotobiotic pigs intranasally (i.n.) with a mutant Escherichia coli heat-labile toxin, LT-R192G (mLT), as mucosal adjuvant. Pigs were challenged with virulent Wa (P1A[8],G1) human rotavirus at postinoculation day (PID) 21 (two-dose VLP regimen) or 28 (three-dose VLP regimen). In vivo antigen-activated antibody-secreting cells (ASC) (effector B cells) and in vitro antigen-reactivated ASC (derived from memory B cells) from intestinal and systemic lymphoid tissues (duodenum, ileum, mesenteric lymph nodes [MLN], spleen, peripheral blood lymphocytes [PBL], and bone marrow lymphocytes) collected at selected times were quantitated by enzyme-linked immunospot assays. Rotavirus-specific immunoglobulin M (IgM), IgA, and IgG ASC and memory B-cell responses were detected by PID 21 or 28 in intestinal and systemic lymphoid tissues after i.n. inoculation with two or three doses of 2/6-VLPs with or without mLT. Greater mean numbers of virus-specific ASC and memory B cells in all tissues prechallenge were induced in pigs inoculated with two doses of SA11 2/6-VLPs plus mLT compared to SA11 2/6-VLPs without mLT. After challenge, anamnestic IgA and IgG ASC and memory B-cell responses were detected in intestinal lymphoid tissues of all VLP-inoculated groups, but serum virus-neutralizing antibody titers were not significantly enhanced compared to the challenged controls. Pigs inoculated with Wa-RF 2/6-VLPs (with or without mLT) developed higher anamnestic IgA and IgG ASC responses in ileum after challenge compared to pigs inoculated with SA11 2/6-VLPs (with or without mLT). Three doses of SA 11 2/6-VLP plus mLT induced the highest mean numbers of IgG memory B cells in MLN, spleen, and PBL among all groups postchallenge. However, no significant protection against diarrhea or virus shedding was evident in any of the 2/6-VLP (with or without mLT)-inoculated pigs after challenge with virulent Wa human rotavirus. These results indicate that 2/6-VLP vaccines are immunogenic in gnotobiotic pigs when inoculated i.n. and that the adjuvant mLT enhanced their immunogenicity. However, i.n. inoculation of gnotobiotic pigs with 2/6-VLPs did not confer protection against human rotavirus challenge.


Asunto(s)
Linfocitos B/inmunología , Toxinas Bacterianas/inmunología , Enterotoxinas/inmunología , Proteínas de Escherichia coli , Vida Libre de Gérmenes/inmunología , Inmunidad Innata , Infecciones por Rotavirus/inmunología , Rotavirus/inmunología , Animales , Formación de Anticuerpos , Bovinos , Infecciones por Escherichia coli/inmunología , Humanos , Mutación , Porcinos , Virión/inmunología
20.
Addiction ; 95(5): 777-89, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10885052

RESUMEN

AIM: An exploratory study was conducted to understand the process of recovery from gambling problems. DESIGN: Media recruitment was used to identify a resolved (n = 43) and a comparison group of active pathological gamblers (n = 63). PARTICIPANTS: Participants showed evidence of significant problems related to gambling as well as high rates of co-morbid mood and substance use disorders. The median length of resolution was 14 months with a range of 6 weeks to 20 years. FINDINGS: Resolved gamblers reported a variety of reasons for quitting gambling, related mainly to emotional and financial factors. They did not experience a greater number of precipitating life events compared with active gamblers but did report an increase in positive and a decrease in negative life events in the year after resolution. Both resolved and active gamblers who had relatively more severe problems were more likely to have had treatment or self-help involvement, whereas those with less severe problems, if resolved, were "naturally recovered". CONCLUSIONS: The results support the need for a continuum of treatment options for problem gamblers and provide helpful information about recovery processes.


Asunto(s)
Juego de Azar/psicología , Aceptación de la Atención de Salud/psicología , Adulto , Anciano , Femenino , Humanos , Masculino , Medios de Comunicación de Masas , Persona de Mediana Edad , Selección de Paciente , Remisión Espontánea , Autorrevelación , Encuestas y Cuestionarios , Resultado del Tratamiento
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