Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
1.
Health Educ Res ; 38(5): 458-468, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36943373

RESUMO

In 2021, guidelines for early childhood education and care were released recommending children are provided access to outdoor areas during all free play sessions to reduce the risk of coronavirus disease of 2019 transmission, aligning with the existing recommendations to increase children's physical activity. There is a need to understand how to disseminate guidelines in this setting as dissemination is a prerequisite of adoption and implementation. This randomized controlled trial explored the impact of a video-based strategy to disseminate guidelines on family day care educators' intentions to adopt outdoor free play guidelines. Educators (N = 255) were randomized to receive a video (intervention) or text-based (usual care) resource via email describing recommendations. Educators were invited to participate in a post-intervention survey at 5-week follow-up assessing intentions to adopt guidelines. The secondary outcomes included knowledge, beliefs about capabilities, beliefs about consequences, social/professional role and identity, goals, implementation of guidelines, acceptability of resource and intervention reach. There was no statistically significant difference between groups in intentions to adopt guidelines [ß = 0.01 (95% confidence interval -0.50 to 0.52), P = 0.97], nor for any secondary outcomes. Further investigation is needed to identify effective dissemination strategies in the family day care setting to increase the adoption of public health guidelines.


Assuntos
COVID-19 , Criança , Humanos , Pré-Escolar , Intenção , Hospital Dia , Creches , Exercício Físico/fisiologia
2.
Growth Horm IGF Res ; 19(3): 212-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18976947

RESUMO

OBJECTIVES: Growth hormone (GH) and its receptor (GHR) are widely expressed in the CNS. During development, GH signaling regulates both proliferation of neural progenitor cells as well as their differentiation into neurons and glia. Here we have examined the effect of GH signaling on adult subventricular zone derived neural progenitor cells cultured as neurospheres. DESIGN: GH was added to adult wild-type (WT) neurosphere cultures and neurosphere growth measured using the MTT cell proliferation assay. To examine the influence of endogenous GH production on neural progenitors, neurospheres derived from GH receptor knockout (GHRKO) mice were examined by measuring neurosphere sizes and Ki67 and TUNEL immunoreactivity. In addition, neurosphere growth curves were compared following long term culture. Finally, the differentiation of WT vs. GHRKO neurospheres was compared using immunocytochemistry for betaIII-tubulin and GFAP. RESULTS: While GH alone was insufficient to support neurosphere formation, it enhanced neurosphere growth by 20% in the presence of epidermal growth factor and fibroblast growth factor-2. Compared to wildtype neurospheres, GHRKO neurospheres were smaller, contained fewer proliferating cells and exhibited reduced self-renewal in long term culture. Addition of GH increased STAT5 phosphorylation levels in neurosphere cells. Upon differentiation, GHRKO neurospheres showed accelerated neurogenesis, although over time similar numbers of betaIII-tubulin positive neurons were generated by cells of both genotypes. CONCLUSIONS: GH functions as an autocrine mitogen in adult neurosphere cultures and promotes proliferation of neural progenitor cells as well as self-renewal of neurosphere cultures. In addition, signaling through the GHR appeared to delay neuronal differentiation in adult neurospheres.


Assuntos
Proliferação de Células/efeitos dos fármacos , Hormônio do Crescimento/farmacologia , Neurogênese , Neurônios/citologia , Neurônios/fisiologia , Receptores de Fatores de Crescimento/fisiologia , Células-Tronco/fisiologia , Animais , Western Blotting , Diferenciação Celular , Células Cultivadas , Técnicas Imunoenzimáticas , Imunoprecipitação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/efeitos dos fármacos , Fosforilação , Fator de Transcrição STAT5 , Esferoides Celulares/metabolismo , Tubulina (Proteína)/metabolismo
3.
J Neuroimmunol ; 206(1-2): 32-8, 2009 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-19027965

RESUMO

Interferons are produced following neural damage as part of the inflammatory response and may thus affect neural stem cell function. We compared the effects of interferon-gamma and interferon-beta on the proliferation and differentiation of adult murine neural progenitors. Both interferons inhibited neurosphere proliferation due to cell cycle arrest in G1 but only interferon-gamma induced neuronal differentiation. Both interferons induced differential phosphorylation of STAT proteins and a modest and late upregulation of the cell cycle regulator p27 but not several other likely cell cycle regulators. Thus in neural progenitor cells, anti-proliferative effects of interferons are not necessarily linked to differentiation.


Assuntos
Células-Tronco Adultas/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Interferon beta/farmacologia , Interferon gama/farmacologia , Neurônios/fisiologia , Análise de Variância , Animais , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Citometria de Fluxo/métodos , Imunoprecipitação , Ventrículos Laterais/citologia , Camundongos , Camundongos Endogâmicos C57BL , Neuritos/efeitos dos fármacos , Neurônios/citologia , Fosforilação/efeitos dos fármacos , Fatores de Transcrição STAT/metabolismo , Fatores de Tempo , Tubulina (Proteína)/metabolismo
6.
Health Educ Res ; 15(4): 463-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11066463

RESUMO

This study evaluated a National Institute for Occupational Safety and Health (NIOSH), Centers for Disease Control and Prevention, Alert concerning the risk and prevention of latex allergy among health care workers. It has been estimated that 8-12% of health care workers are sensitized to latex. NIOSH Alerts are publications that are intended to educate stakeholders about risks in the workplace; this Alert contained four recommendations for administrative control measures that hospital decision makers could adopt to reduce the risk of latex allergy to employees. The Alert was mailed to a random selection of Directors of Infection Control and Directors of Nursing in hospitals in the US. A random sample of these targeted recipients and a control group were surveyed by telephone (N = 298). Although nearly all of the respondents were concerned about latex allergy (96%), those reporting having seen the Alert were significantly more likely to report an intention to advocate for one or more of the control measures.


Assuntos
Fidelidade a Diretrizes/estatística & dados numéricos , Administração Hospitalar/normas , Hipersensibilidade ao Látex/prevenção & controle , Saúde Ocupacional , Recursos Humanos em Hospital/normas , Tomada de Decisões Gerenciais , Luvas Protetoras/normas , Administração Hospitalar/estatística & dados numéricos , Humanos , National Institute for Occupational Safety and Health, U.S. , Inovação Organizacional , Gestão de Riscos , Estados Unidos
8.
Pediatr Res ; 45(3): 355-62, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10088654

RESUMO

Bilirubin, the breakdown product of heme from erythrocytes, accumulates in the neonate in the first days of life. In recent years, the antioxidant properties of bilirubin have been demonstrated in vitro and in vivo, yet it is clear that bilirubin can be toxic to cells. To study the range in which bilirubin exerts its beneficial effect, we used erythrocytes derived from cord blood and incubated them with 0-60 mg/dL bilirubin combined with 3 g/dL BSA (bilirubin/BSA) to mimic physiologic and pathologic conditions. Oxidative stress was induced by incubating the erythrocytes with a solution of 0.6 mM H2O2 and 0.15 M CuSO4 to generate hydroxyl radical mediated injury. The loss of fluorescence of cis-parinaric acid and the degree of protein oxidation of erythrocyte membranes were assessed. Additionally, we determined erythrocyte membrane integrity, glucose-6 phosphate dehydrogenase activity, and adenosine triphosphatase activity before and after incubation with bilirubin/BSA. Incubation with bilirubin/BSA at concentrations up to 60 mg/dL and a bilirubin/BSA molar ratio of two was associated with dose-dependent protection of erythrocytes against lipid peroxidation. However, concentrations of bilirubin equal to or exceeding 30 mg/dL and a bilirubin:BSA ratio of one were associated with increased protein oxidation, decreased erythrocyte glucose-6 phosphate dehydrogenase and adenosine triphosphatase activity, and altered cell membrane integrity. We conclude that bilirubin, at physiologic concentrations, protects neonatal red blood cells against oxidative stress in the presence of physiologic concentrations of BSA but that bilirubin concentrations of 30 mg/dL or higher and a bilirubin:BSA ratio of greater than one are associated with significant cytotoxicity.


Assuntos
Antioxidantes/farmacologia , Bilirrubina/farmacologia , Eritrócitos/efeitos dos fármacos , Sangue Fetal , Relação Dose-Resposta a Droga , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/patologia , Eritrócitos/metabolismo , Eritrócitos/patologia , Humanos , Recém-Nascido , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo
9.
Blood ; 92(11): 4404-14, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9834247

RESUMO

In erythrocytes, 80-kD protein 4.1R regulates critical membrane properties of deformability and mechanical strength. However, previously obtained data suggest that multiple isoforms of protein 4. 1, generated by alternative pre-mRNA splicing, are expressed during erythroid differentiation. Erythroid precursors use two splice acceptor sites at the 5' end of exon 2, thereby generating two populations of 4.1 RNA: one that includes an upstream AUG-1 in exon 2' and encodes high molecular weight isoforms, and another that skips AUG-1 in exon 2' and encodes 4.1 by initiation at a downstream AUG-2 in exon 4. To begin an analysis of the complex picture of protein 4.1R expression and function during erythropoiesis, we determined the number and primary structure of 4.1R isoforms expressed in erythroblasts. We used reverse-transcription polymerase chain reaction to amplify and clone full-length coding domains from the population of 4.1R cDNA containing AUG-1 and the population excluding AUG-1. We observed an impressive repertoire of 4.1R isoforms that included 7 major and 11 minor splice variants, thus providing the first definitive characterization of 4.1R primary structures in a single-cell lineage. 4.1R isoforms, transfected into COS-7 cells, distributed to the nucleus, cytoplasm, plasma membrane, and apparent centrosome. We confirmed previous studies showing that inclusion of exon 16 was essential for efficient nuclear localization. Unexpectedly, immunochemical analysis of COS-7 cells transfected with an isoform lacking both AUG-1 and AUG-2 documented that a previously unidentified downstream translation initiation codon located in exon 8 can regulate expression of 4.1R. We speculate that the repertoire of primary structure of 4.1R dictates its distinct binding partners and functions during erythropoiesis.


Assuntos
Proteínas do Citoesqueleto , Eritropoese/fisiologia , Proteínas de Membrana/metabolismo , Neuropeptídeos , Processamento Alternativo , Animais , Células COS , Diferenciação Celular , Eritrócitos/citologia , Eritrócitos/fisiologia , Regulação da Expressão Gênica , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/genética , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transfecção
10.
Anaesthesia ; 53(6): 529-35, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9709136

RESUMO

To examine the risk factors of early postoperative emergencies that required an intensive care team intervention, a matched nested case-control study (34 cases and 126 controls) was conducted. Over a 17-month period, the incidence of early postoperative emergencies occurring within 48 h of surgery was 0.21% (95% confidence intervals (CI): 0.14%-0.30%). The intensive care team treated two cardiac arrests and three respiratory arrests. The major physiological changes which led to ward staff summoning an intensive care team were hypotension (13 cases) and a decreased level of consciousness (nine cases). Significant associations with early postoperative emergencies were high ASA (> or = IV) physical status grades (odds ratio: 4.51, 95% CI: 1.24-16.40) and surgery performed outside normal working hours (odds ratio: 4.40, 95% CI: 1.41-13.69). High-risk patients may benefit from a visit by a postoperative care team during the early postoperative period but this requires further evaluation.


Assuntos
Cuidados Críticos , Equipe de Assistência ao Paciente , Complicações Pós-Operatórias/terapia , Adulto , Idoso , Análise de Variância , Estudos de Casos e Controles , Emergências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , New South Wales , Assistência Noturna , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Fatores de Risco , Índice de Gravidade de Doença
11.
Can J Anaesth ; 44(9): 946-54, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9305558

RESUMO

PURPOSE: To determine the risk of unanticipated intraoperative events (UIE) in patients assessed at a preanaesthetic clinic compared with those not assessed at the clinic. METHODS: Preoperative and intraoperative data were collected on 6130 elective surgical patients by procedural anaesthetists over a 12-month-period at an Australian tertiary referral hospital. The procedural anaesthetists rated the level of preparation and identified predefined unanticipated intraoperative events. A logistic regression model was used to identify significant risk factors of UIE and was further validated on another sample of 482 patients (one month) by a goodness-of-fit test. RESULTS: Of the 6130 elective surgical patients, 2000 (33%) had been assessed at the preanaesthetic clinic. There was a greater proportion of ASA II to IV patients seen at the clinic than patients not assessed at the clinic (chi 2(3) = 689.92, P < 0.001). Nonclinic patients were more likely to be inadequately prepared than clinic patients (RRunadjusted = 1.61, 95% CI: 1.25 to 2.04, P < 0.001). The overall incidence of intraoperative events was 4.14% (95% CI: 3.64% to 4.64%). Despite adjusting for the preparation level, type of anaesthesia, admission category, ASA physical status and duration of anaesthesia, clinic patients were 1.94 (95% CI: 1.42 to 2.64) times more likely to experience an UIE than nonclinic patients (P < 0.001). CONCLUSION: Although clinic patients were more often optimally prepared, their adjusted risk of UIE was higher than nonclinic patients. The procedural anaesthetist needs to be vigilant with these high risk patients, even if they have been assessed at a preanaesthetic clinic.


Assuntos
Anestesiologia , Complicações Intraoperatórias , Cuidados Pré-Operatórios , Medição de Risco , Adulto , Procedimentos Cirúrgicos Ambulatórios , Anestesia por Condução , Anestesia Geral , Estudos de Coortes , Intervalos de Confiança , Procedimentos Cirúrgicos Eletivos , Feminino , Nível de Saúde , Humanos , Incidência , Modelos Logísticos , Masculino , Anamnese , Pessoa de Meia-Idade , Análise Multivariada , Avaliação em Enfermagem , Admissão do Paciente , Seleção de Pacientes , Curva ROC , Reprodutibilidade dos Testes , Fatores de Risco , Procedimentos Cirúrgicos Operatórios/classificação , Inquéritos e Questionários , Fatores de Tempo
12.
Proc Natl Acad Sci U S A ; 94(10): 5467-72, 1997 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-11038545

RESUMO

Transcripts for two genes expressed early in alfalfa nodule development (MsENOD40 and MsENOD2) are found in mycorrhizal roots, but not in noncolonized roots or in roots infected with the fungal pathogen Rhizoctonia solani. These same two early nodulin genes are expressed in uninoculated roots upon application of the cytokinin 6-benzylaminopurine. Correlated with the expression of the two early nodulin genes, we found that mycorrhizal roots contain higher levels of trans-zeatin riboside than nonmycorrhizal roots. These data suggest that there may be conservation of signal transduction pathways between the two symbioses-nitrogen-fixing nodules and phosphate-acquiring mycorrhizae.

13.
Anaesth Intensive Care ; 24(6): 685-93, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8971318

RESUMO

We have identified some of the most frequently measured anaesthetic outcomes and their independent risk factors, and discussed the limitations and advantages in using various risk adjustment strategies. Many studies suggest that preoperative assessments may contribute to preventing the occurrence of anaesthetic-related morbidity and mortality, and to high levels of patient satisfaction. The use of health status measurements as a preoperative screening tool in assessing anaesthetic risk offers a potential area for future work. Research into measuring anaesthetic outcomes in a reliable and valid manner will be an important tool in improving standards of anaesthetic practice and in delivering quality anaesthesia to our patients.


Assuntos
Anestesia/efeitos adversos , Avaliação de Resultados em Cuidados de Saúde , Anestesia/mortalidade , Nível de Saúde , Humanos , Satisfação do Paciente , Fatores de Risco
14.
Pediatr Res ; 40(6): 815-21, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8947956

RESUMO

In the neonatal lung, hyperoxic exposure is associated with induction of various genes and critical antioxidants. Heme oxygenase, specifically the HO-1 isoenzyme, is regulated in oxidant stress and may also serve to limit oxidative damage. However, it is not known whether neonatal lung HO-1 is regulated in hyperoxia specifically and, if so, what type of regulation occurs. Therefore, we attempted to answer these questions using newly born (< 12 h) Wistar rats exposed to hyperoxia for 3 d. Neonatal rat lungs were evaluated daily for total HO activity, immunoreactive HO-1 protein, and steady state levels of HO-1 mRNA and compared with air-exposed controls. In neonatal rats, we noted an increased lung HO activity after 3 d of hyperoxic exposure. Additionally, evaluation of HO activity after immunoprecipitation of HO-1 protein suggested that HO-1 contributed most of the increase in lung total HO activity observed in hyperoxia. Nonetheless, we did not see a significant difference in immunoreactive HO-1 protein in neonatal lungs after 3 d of hyperoxic exposure, although we did so on d 2. Also, in contrast with previous reports, we did not detect any significant differences in steady state levels of HO-1 mRNA on any day of hyperoxic exposure compared with air. We therefore conclude that neonatal rat lung HO-1 is regulated in hyperoxia and speculate that the regulation of neonatal lung HO-1 occurs by posttranscriptional mechanisms, at least within the first days of hyperoxic exposure.


Assuntos
Envelhecimento/metabolismo , Regulação Enzimológica da Expressão Gênica , Heme Oxigenase (Desciclizante)/biossíntese , Hiperóxia , Pulmão/enzimologia , Animais , Animais Recém-Nascidos , Regulação da Expressão Gênica no Desenvolvimento , Isoenzimas/biossíntese , Peroxidação de Lipídeos , Pulmão/crescimento & desenvolvimento , Reação em Cadeia da Polimerase , Ratos , Ratos Wistar
16.
Crit Care Med ; 24(4): 618-22, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8612413

RESUMO

OBJECTIVES: To evaluate the training of clinical staff in the use of interhospital transfer guidelines and to examine the underlying decision-making behavior in organizing patient transfers between hospitals. DESIGN: Prospective assessment of clinical scenarios, given before (time 1), immediately after (time 2), and 3 months after (time 3) a program informing clinical staff about the use of interhospital transfer guidelines. SETTING: Three emergency departments and one intensive care unit at three hospitals and a medical retrieval service in Sydney, Australia. SUBJECTS: Physicians, nurses, and a paramedic working in critical care areas and at a medical retrieval service. MEASUREMENTS AND MAIN RESULTS: A questionnaire containing clinical scenarios was administered to clinical staff. There was a significant difference in mean scores for selecting the appropriate escort levels across time (F2,78 = 24.2; p < .01) and for participant's experience with interhospital transfer (F2,39 = 4.63; p = .02). Significant improvement in mean scores occurred between time 1 (7.55 +/- 1.84 and time 2 (9.48 +/- 1.47) (t41 = -6.21; p < .01). The improvement in selecting appropriate escorts was maintained at time 3 (mean score 9.86 +/- 2.01). The error rate for inappropriate assignment of low levels of escorts decreased from 35% (time 1) to 10% (time 2) and 14% (time 3). Using conjoint analysis, there were large variations in the decision-making behaviour between each time period. The relative importance of each factor in influencing the decision to organize an escort at time 3 were as follows: treatment (43%); physiology (29%); patient age (24%); and diagnosis (4%). The decision-making model observed at time 3 had a high predictive value (87%) as compared with the model at time 1 (48%). CONCLUSION: Clinical staff can make informed and appropriate decisions by using standardized guidelines when organizing interhospital transfers.


Assuntos
Cuidados Críticos/normas , Tomada de Decisões Gerenciais , Serviço Hospitalar de Emergência/normas , Unidades de Terapia Intensiva/normas , Transferência de Pacientes/normas , Análise de Variância , Intervalos de Confiança , Cuidados Críticos/estatística & dados numéricos , Serviço Hospitalar de Emergência/organização & administração , Serviço Hospitalar de Emergência/estatística & dados numéricos , Guias como Assunto , Humanos , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/estatística & dados numéricos , Corpo Clínico Hospitalar/educação , Corpo Clínico Hospitalar/organização & administração , Corpo Clínico Hospitalar/estatística & dados numéricos , New South Wales , Transferência de Pacientes/organização & administração , Transferência de Pacientes/estatística & dados numéricos , Estudos Prospectivos
17.
Vet Pathol ; 33(2): 159-70, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8801709

RESUMO

One hundred 4-week-old cesarean-derived colostrum-deprived pigs were inoculated with one of two different US porcine reproductive and respiratory syndrome virus (PRRSV) isolates (VR2385, VR2431) or the European Lelystad virus to detect and compare the location and amount of virus antigen. Interstitial pneumonia, myocarditis, lymphadenopathy, and encephalitis were consistently seen in all three groups; however, disease and lesions were more severe in the VR2385 group. Immunohistochemical evaluation of formalin-fixed tissues revealed virus antigen in alveolar macrophages in lungs of 22/25, 14/25, 14/25, and 0/25 of the VR2385, VR2431, Lelystad, and control pigs, respectively. Follicular macrophages and dendritic cells in the lymph nodes of 14/25, 10/25, 10/25, and 0/25 pigs from the VR2385, VR2431, Lelystad, and control groups, respectively, stained positive for virus antigen. Similar cells in the tonsils from 25/25, 21/25, 23/25, and 0/25 pigs from the VR2385, VR2431, Lelystad, and control groups, respectively, stained positive for virus antigen. Other tissues and cells in which virus antigen was detected included macrophages and endothelial cells in the heart, macrophages, and interdigitating cells in the thymus, macrophages and dendritic cells in the spleen and Peyer's patches, and macrophages in hepatic sinusoids, renal medullary interstitium, and adrenal gland. PRRSV persisted in macrophages in the lung, tonsil, lymph node, and spleen for at least 28 days. Significantly more PRRSV antigen was detected in the lung (P < 0.01), lymph nodes (P < or = 0.05), and tonsils (P < 0.05) of the VR2385 pigs than was detected in the same tissues of the VR2431 and Lelystad pigs. The cell types in which PRRSV antigen was detected and the distribution of PRRSV antigen-positive cells within particular tissues and organs were generally similar for the different virus inoculation groups despite differences in virulence of the isolates.


Assuntos
Antígenos Virais/análise , Arterivirus/imunologia , Infertilidade Feminina/veterinária , Pneumopatias/veterinária , Doenças dos Suínos/virologia , Animais , Arterivirus/isolamento & purificação , Arterivirus/patogenicidade , Feminino , Infertilidade Feminina/virologia , Pneumopatias/virologia , Suínos , Síndrome , Distribuição Tecidual
18.
J Vet Diagn Invest ; 8(1): 11-20, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9026065

RESUMO

One hundred forty-six 5-week- old cesarean-derived, colostrum-deprived (CDCD) pigs were inoculated intranasally with 1 of 9 US porcine reproductive and respiratory syndrome virus (PRRSV) isolates. Differences were found in severity of clinical respiratory disease, rectal temperatures (P < or = 0.001), gross lung lesions (P < or = 0.001), and microscopic lung lesions (P < or = 0.05). Gross lung lesions were generally most severe 10 days postinoculation and were distributed primarily in the cranial, middle, and accessory lobes and ventromedial portion of the caudal lung lobes. Mean gross lung lesion scores estimating the percentage of lung affected by pneumonia at 10 days postinoculation ranged from 16.7% +/- 2.8% (mean +/- SEM, n = 10) for isolate ISU-51 to 62.4% +/- 5.7% (n = 10) for isolate ISU-28. Microscopic lung lesions were characterized by hyperplastic and hypertrophied type 2 pneumocytes, septal infiltration by mononuclear cells, and accumulation of necrotic alveolar exudate. Lymph node follicular hyperplasia and focal necrosis was seen with all 9 isolates. This CDCD pig model was useful for demonstration of significant differences in pathogenicity among US PRRSV isolates. This difference in pathogenicity may help explain the variation of severity of clinical disease observed in field outbreaks of porcine reproductive and respiratory syndrome and should provide for meaningful comparison of PRRSV genotypes.


Assuntos
Infecções por Arterivirus/veterinária , Arterivirus/patogenicidade , Colostro , Pulmão/patologia , Doenças dos Suínos , Animais , Arterivirus/isolamento & purificação , Infecções por Arterivirus/patologia , Infecções por Arterivirus/fisiopatologia , Cesárea , Feminino , Pulmão/virologia , Pneumopatias/patologia , Pneumopatias/veterinária , Pneumopatias/virologia , Gravidez , Suínos , Síndrome , Virulência
19.
Vet Pathol ; 32(6): 648-60, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8592800

RESUMO

The Lelystad virus or one of two US isolates (VR2385, VR2431) of porcine reproductive and respiratory syndrome virus were given intranasally to 25 4-week-old cesarian-derived colostrum-deprived pigs. Pigs from these groups were necropsied at 1, 2, 3, 5, 7, 10, 15, 21, or 28 days postinoculation. The Lelystad virus and VR2431 induced mild transient pyrexia, dyspnea, and tachypnea. VR2385 induced labored and rapid abdominal respiration, pyrexia, lethargy, anorexia, and patchy dermal cyanosis. All three isolates induced multifocal tan-mottled consolidation involving 6.8% (n = 9; SEM = 3.4) of the lung for Lelystad, 9.7% (n = 9, SEM = 2.7) of the lung for VR2431, and 54.2% (n = 9, SEM = 4.4) of the lung for VR2385 at 10 days postinoculation. Characteristic microscopic lung lesions consisted of type 2 pneumocyte hypertrophy and hyperplasia, necrotic debris and increased mixed inflammatory cells in alveolar spaces, and alveolar septal infiltration with mononuclear cells. Lymphadenopathy with follicular hypertrophy, hyperplasia, and necrosis was consistently seen. Similar follicular lesions were also seen in Peyer's patches and tonsils. Lymphohistiocytic myocarditis and encephalitis were reproduced with all three isolates. Clinical respiratory disease and gross and microscopic lung lesion scores were considerably and significantly more severe in the VR2385-inoculated pigs. All three viruses were readily isolated from sera, lungs, and tonsils throughout the 28 days of the study. The lymphoid and respiratory systems have the most remarkable lesions and appear to be the major site of replication of these viruses. This work demonstrated a marked difference in pathogenicity of porcine reproductive and respiratory syndrome isolates.


Assuntos
Infecções por Arterivirus/veterinária , Arterivirus/patogenicidade , Doenças dos Suínos/virologia , Glândulas Suprarrenais/patologia , Glândulas Suprarrenais/virologia , Animais , Arterivirus/isolamento & purificação , Arterivirus/fisiologia , Infecções por Arterivirus/virologia , Encéfalo/patologia , Encéfalo/virologia , Modelos Animais de Doenças , Dispneia/etiologia , Dispneia/veterinária , Encefalite/etiologia , Encefalite/veterinária , Feminino , Febre/etiologia , Febre/veterinária , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Coração/virologia , Intestino Delgado/patologia , Intestino Delgado/virologia , Pulmão/patologia , Pulmão/virologia , Pneumopatias/etiologia , Pneumopatias/veterinária , Linfonodos/patologia , Linfonodos/virologia , Miocárdio/patologia , Tonsila Palatina/patologia , Tonsila Palatina/virologia , Baço/patologia , Baço/virologia , Suínos , Conchas Nasais/patologia
20.
Arch Virol ; 140(4): 745-55, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7794115

RESUMO

The putative membrane (M) protein (ORF 6) and nucleocapsid (N) protein (ORF 7) genes of five U.S. isolates of porcine reproductive and respiratory syndrome virus (PRRSV) with differing virulence were cloned and sequenced. To determine the genetic variation and the phylogenetic relationship of PRRSV, the deduced amino acid sequences of the putative M and N proteins from these isolates were aligned, to the extent known, with other PRRSV isolates, and also other members of the proposed arterivirus group including lactate dehydrogenase-elevating virus (LDV) and equine arteritis virus (EAV). There was 96-100% amino acid sequence identity in the putative M and N genes among U.S. and Canadian PRRSV isolates with differing virulence. However, their amino acid sequences varied extensively from those of European PRRSV isolates, and displayed only 57-59% and 78-81% identity, respectively. The phylogenetic trees constructed on the basis of the putative M and N genes of the proposed arterivirus group were similar and indicated that both U.S. and European PRRSV isolates were related to LDV and were distantly related to EAV. The U.S. and European PRRSV isolates fell into two distinct groups, suggesting that U.S. and European PRRSV isolates represent two distinct genotypes.


Assuntos
Arterivirus/classificação , Capsídeo/genética , Proteínas do Core Viral/genética , Proteínas da Matriz Viral/genética , Sequência de Aminoácidos , Animais , Arterivirus/genética , Sequência de Bases , Primers do DNA , DNA Viral , Europa (Continente) , Genes Virais , Genótipo , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Suínos , Estados Unidos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...