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1.
Multivariate Behav Res ; : 1-14, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36762914

RESUMO

This study is the first to investigate how 3-year-olds learn simple rules from feedback using the Toddler Card Sorting Task (TCST). To account for intra- and inter- individual differences in the learning process, latent Markov models were fitted to the time series of accuracy responses using maximum likelihood techniques (Visser et al., 2002). In a first, exploratory study (N = 110, 3- to 5-years olds) a considerable group of 3-year olds applied a hypothesis testing learning strategy. A second study confirmed these results with a preregistered study (3-years olds, N = 60). Under supportive learning conditions, a majority of 3-year- olds was capable of hypothesis testing. Furthermore, older children and those with bigger working memory capacities were more likely to use hypothesis testing, even though the latter group perseverated more than younger children or those with smaller working memory capacities. 3-year-olds are more advanced feedback-learners than assumed.

2.
Pancreatology ; 22(7): 973-986, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35864067

RESUMO

BACKGROUND AND AIMS: Pancreatic cancer has a dismal prognosis. So far, imaging has been proven incapable of establishing an early enough diagnosis. Thus, biomarkers are urgently needed for early detection and improved survival. Our aim was to evaluate the pooled diagnostic performance of DNA alterations in pancreatic juice. METHODS: A systematic literature search was performed in EMBASE, MEDLINE Ovid, Cochrane CENTRAL and Web of Science for studies concerning the diagnostic performance of DNA alterations in pancreatic juice to differentiate patients with high-grade dysplasia or pancreatic cancer from controls. Study quality was assessed using QUADAS-2. The pooled prevalence, sensitivity, specificity and diagnostic odds ratio were calculated. RESULTS: Studies mostly concerned cell-free DNA mutations (32 studies: 939 cases, 1678 controls) and methylation patterns (14 studies: 579 cases, 467 controls). KRAS, TP53, CDKN2A, GNAS and SMAD4 mutations were evaluated most. Of these, TP53 had the highest diagnostic performance with a pooled sensitivity of 42% (95% CI: 31-54%), specificity of 98% (95%-CI: 92%-100%) and diagnostic odds ratio of 36 (95% CI: 9-133). Of DNA methylation patterns, hypermethylation of CDKN2A, NPTX2 and ppENK were studied most. Hypermethylation of NPTX2 performed best with a sensitivity of 39-70% and specificity of 94-100% for distinguishing pancreatic cancer from controls. CONCLUSIONS: This meta-analysis shows that, in pancreatic juice, the presence of distinct DNA mutations (TP53, SMAD4 or CDKN2A) and NPTX2 hypermethylation have a high specificity (close to 100%) for the presence of high-grade dysplasia or pancreatic cancer. However, the sensitivity of these DNA alterations is poor to moderate, yet may increase if they are combined in a panel.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Carcinoma Ductal Pancreático/diagnóstico , Detecção Precoce de Câncer , Mutação , Suco Pancreático/química , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas
3.
Langmuir ; 37(21): 6549-6555, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34008985

RESUMO

When proteins in aqueous solutions are exposed to solid substrates, they adsorb due to the dynamic interplay of electrostatic, van der Waals, and hydration interactions and do so in a rather irreversible fashion, which makes protein recovery troublesome. Here, we use a gold electrode as the solid substrate and modulate the surface potential to systematically induce protein adsorption as well as partial desorption. We use different methods such as surface plasmon resonance, atomic force microscopy, and electrowetting and show that biasing the electrode to more negative potentials (by -0.4 V compared to the open-circuit potential at pH 6) results in an increased adsorption barrier of 6 kJ mol-1 for the negatively charged protein ß-lactoglobulin. Further, we clearly demonstrate that this is due to an increased double layer potential of -0.06 V and an increase in hydration repulsion. This indicates that an electric potential can directly influence surface interactions and thus induce partial ß-lactoglobulin desorption. These observations can be the basis for biosensors as well as separation technologies that use only one trigger to steer protein ad- and desorption, which is low in energy requirement and does not generate large waste streams, as is the case for standard protein separation technologies.


Assuntos
Água , Adsorção , Eletrodos , Microscopia de Força Atômica , Eletricidade Estática
4.
R Soc Open Sci ; 11(9): 240049, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39233722

RESUMO

Paranormal beliefs encompass a wide variety of phenomena, including the existence of supernatural entities such as ghosts and witches, as well as extraordinary human abilities such as telepathy and clairvoyance. In the current study, we used a nationally representative sample ( N = 2534 ) to investigate the presence and correlates of paranormal beliefs among the secular Dutch population. The results indicated that most single paranormal phenomena (e.g. belief in clairvoyance) are endorsed by 10-20% of Dutch respondents; however, 55.6% of respondents qualify as paranormal believers based on the preregistered criterion that they believe in at least one phenomenon with considerable certainty. In addition, we invited four analysis teams with different methodological expertise to assess the structure of paranormal beliefs using traditional factor analysis, network analysis, Bayesian network analysis and latent class analysis (LCA). The teams' analyses indicated adequate fit of a four-factor structure reported in a 1985 study, but also emphasized different conclusions across techniques; network analyses showed evidence against strong connectedness within most clusters, and suggested a five-cluster structure. The application of various analytic techniques painted a nuanced picture of paranormal beliefs and believers in The Netherlands and suggests that despite increased secularization, subgroups of the general population still believe in paranormal phenomena.

5.
Burns ; 50(1): 31-40, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37985268

RESUMO

BACKGROUND: The use of patient-reported outcomes to improve burn care increases. Little is known on burn patients' views on what outcomes are most important, and about preferences regarding online Patient Reported Outcome Measures (PROMs). Therefore, this study assessed what outcomes matter most to patients, and gained insights into patient preferences towards the use of online PROMs. METHODS: Adult patients (≥18 years old), 3-36 months after injury completed a survey measuring importance of outcomes, separately for three time periods: during admission, short-term (<6 months) and long-term (6-24 months) after burn injury. Both open and closed-ended questions were used. Furthermore, preferences regarding the use of patient-reported outcome measures in burn care were queried. RESULTS: A total of 140 patients were included (response rate: 27%). 'Not having pain' and 'good wound healing' were identified as very important outcomes. Also, 'physical functioning at pre-injury level', 'being independent' and 'taking care of yourself' were considered very important outcomes. The top-ten of most important outcomes largely overlapped in all three time periods. Most patients (84%) had no problems with online questionnaires, and many (67%) indicated that it should take up to 15 minutes. Patients' opinions differed widely on the preferred frequency of follow-up. CONCLUSIONS: Not having pain and good wound healing were considered very important during the whole recovery of burns; in addition, physical functioning at pre-injury level, being independent, and taking care of yourself were deemed very important in the short and long-term. These outcomes are recommended to be used in burn care and research, although careful selection of outcomes remains crucial as patients prefer online questionnaires up to 15 minutes.


Assuntos
Queimaduras , Qualidade de Vida , Adulto , Humanos , Adolescente , Países Baixos , Queimaduras/terapia , Medidas de Resultados Relatados pelo Paciente , Dor
6.
Burns ; 50(7): 1925-1934, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38902131

RESUMO

BACKGROUND: Value-based healthcare (VBHC) is increasingly implemented in healthcare worldwide. Transparent measurement of the outcomes most important and relevant to patients is essential in VBHC, which is supported by a core set of most important quality indicators and outcomes. Therefore, the aim of this study was to develop a VBHC-burns core set for adult burn patients. METHODS: A three-round modified national Delphi study, including 44 outcomes and 24 quality indicators, was conducted to reach consensus among Dutch patients, burn care professionals and researchers. Items were rated on a nine-point Likert scale and selected if ≥ 70% in each group considered an item 'important'. Subsequently, instruments quantifying selected outcomes were identified based on a literature review and were chosen in a consensus meeting using recommendations from the Dutch consensus-based standard set and the Dutch Centre of Expertise on Health Disparities. Time assessment points were chosen to reflect the burn care and patient recovery process. Finally, the initial core set was evaluated in practice, leading to the adapted VBHC-burns core set. RESULTS: Twenty-seven patients, 63 burn care professionals and 23 researchers participated. Ten outcomes and four quality indicators were selected in the Delphi study, including the outcomes pain, wound healing, physical activity, self-care, independence, return to work, depression, itching, scar flexibility and return to school. Quality indicators included shared decision-making (SDM), the number of patients receiving aftercare, determination of burn depth, and assessment of active range of motion. After evaluation of its use in clinical practice, the core set included all items except SDM, which are assessed by 9 patient-reported outcome instruments or measured in clinical care. Assessment time points included are at discharge, 2 weeks, 3 months, 12 months after discharge and annually afterwards. CONCLUSION: A VBHC-burns core set was developed, consisting of outcomes and quality indicators that are important to burn patients and burn care professionals. The VBHC-burns core set is now systemically monitored and analysed in Dutch burn care to improve care and patient relevant outcomes. As improving burn care and patient relevant outcomes is important worldwide, the developed VBHC-burns core set could be inspiring for other countries.


Assuntos
Queimaduras , Técnica Delphi , Indicadores de Qualidade em Assistência à Saúde , Humanos , Queimaduras/terapia , Adulto , Países Baixos , Masculino , Feminino , Pessoa de Meia-Idade , Consenso , Cicatrização , Autocuidado , Retorno ao Trabalho , Dor , Avaliação de Resultados em Cuidados de Saúde , Medidas de Resultados Relatados pelo Paciente , Prurido/terapia , Cuidados de Saúde Baseados em Valores
7.
Anaesthesia ; 68(1): 74-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23121322

RESUMO

We studied tracheal intubation in manikins and patients with a camera embedded in the tip of the tracheal tube (Vivasight(™) ). Four people in two teams and two individuals attempted intubation of a manikin through an i-gel(™) 10 times each. The tracheas of 12 patients with a Mallampati grade of 1 were intubated with a Vivasight tracheal tube through a Berman airway, passed over a Frova(™) introducer. All 60 manikin intubations were successful, taking a mean (SD) time of 1.4 (0.5) s. The fastest intubation was performed in 0.5 s. All 12 participants' tracheas were successfully intubated in a median (IQR [range]) time of 90 (70-120 [50-210]) s. Seven participants complained of a sore throat, comparable with earlier findings for standard laryngoscopy and intubation: five mild; one moderate; and one severe. Tracheal intubation with the Vivasight through the i-gel or Berman airway is an alternative to existing techniques, against which it should be compared in randomised controlled trials in human participants. It has potential as a fast airway rescue technique.


Assuntos
Manuseio das Vias Aéreas/instrumentação , Manuseio das Vias Aéreas/métodos , Intubação Intratraqueal/instrumentação , Intubação Intratraqueal/métodos , Laringoscópios , Adulto , Análise de Variância , Anestesia Geral , Estudos de Viabilidade , Feminino , Humanos , Máscaras Laríngeas , Laringoscopia , Masculino , Manequins , Pessoa de Meia-Idade , Faringite/epidemiologia , Faringite/etiologia , Complicações Pós-Operatórias/epidemiologia , Tamanho da Amostra
8.
Mult Scler ; 17(4): 441-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21148017

RESUMO

BACKGROUND: Acute disseminated encephalomyelitis (ADEM) affects children more frequently than adults. Current studies investigating ADEM in different age groups are difficult to compare. OBJECTIVE: To investigate whether the clinical presentation, outcome and disease course of ADEM differ between adults and children. METHODS: Disease characteristics of 25 adults and 92 children suffering from ADEM between 1988 and 2008 were compared. RESULTS: The most common presenting symptoms of ADEM in both groups were pyramidal signs and encephalopathy. Ataxia occurred more frequently in children (p = 0.002). In general, MRI showed ill-defined and large white matter lesions in both groups, whereas periventricular lesions were more prevalent in adults (p = 0.001). In adults, duration of hospitalization was longer (p = 0.002) and intensive care unit (ICU) admission was more frequently required (p = 0.043). Three adults (12%) and one child (1%) died (p = 0.030). Fewer adults had complete motor recovery after their first clinical event (p < 0.001). In 73 patients follow-up time was ≥ 2 years and most of these patients remained monophasic. Although relapses after ADEM can occur, only one adult (5%) and five children (6%) converted to MS. CONCLUSIONS: The clinical presentations in children and adults share similarities, but the disease course and outcome of ADEM is more severe in adults with respect to hospitalization, ICU admission, recovery and mortality.


Assuntos
Progressão da Doença , Encefalomielite Aguda Disseminada/diagnóstico , Índice de Gravidade de Doença , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Encéfalo/fisiopatologia , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Encefalomielite Aguda Disseminada/patologia , Encefalomielite Aguda Disseminada/fisiopatologia , Feminino , Seguimentos , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
9.
Cardiovasc Intervent Radiol ; 44(6): 952-958, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33462682

RESUMO

PURPOSE: To investigate the performance of two microwave ablation (MWA) systems regarding ablation volume, ablation shape and variability. MATERIALS AND METHODS: In this ex vivo study, the Emprint and Amica MWA systems were used to ablate porcine livers at 4 different settings of time and power (3 and 5 minutes at 60 and 80 Watt). In total, 48 ablations were analysed for ablation size and shape using Vitrea Advanced Visualization software after acquisition of a 7T MRI scan. RESULTS: Emprint ablations were smaller (11,1 vs. 21,1 mL p < 0.001), more spherical (sphericity index of 0.89 vs. 0.59 p < 0.001) and showed less variability than Amica ablations. In both systems, longer ablation time and higher power resulted in significantly larger ablation volumes. CONCLUSION: Emprint ablations were more spherical, and the results showed a lower variability than those of Amica ablations. This comes at the price of smaller ablation volumes.


Assuntos
Técnicas de Ablação/métodos , Fígado/cirurgia , Animais , Ablação por Cateter/métodos , Micro-Ondas , Modelos Animais , Reprodutibilidade dos Testes , Suínos
10.
Infant Behav Dev ; 44: 38-48, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27281348

RESUMO

A robust set of studies show that adults make more horizontal than vertical and oblique saccades, while scanning real-world scenes. In this paper we study the horizontal bias in infants. The directions of eye movements were calculated for 41 infants (M=8.40 months, SD=3.74, range=3.48-15.47) and 47 adults (M=21.74 years, SD=4.54, range=17.89-39.84) while viewing 28 real-world scenes. Saccade directions were binned to study the proportion of saccades in the horizontal, vertical and oblique directions. In addition, saccade directions were also modeled using a mixture of Von Mises distributions, to account for the relatively large amount of variance in infants data. Horizontal bias was replicated in adults and also found in infants, using both the binning and Von Mises approach. Moreover, a developmental pattern was observed in which older infants are more precise in targeting their saccades than younger infants. That infants have a horizontal bias is important in understanding infants' eye movements. Future studies should account for the horizontal bias in their designs and analyses.


Assuntos
Desenvolvimento Infantil , Movimentos Sacádicos , Adolescente , Adulto , Feminino , Humanos , Lactente , Masculino , Estimulação Luminosa , Adulto Jovem
11.
Vet Q ; 27(1): 2-10, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15835279

RESUMO

Clinical and pathological diagnoses were compared in a prospective study of 145 dogs. A diagnostic work up had been performed on all dogs of which 36 (24.8%) died and 109 (75.2%) were euthanatized. In 119 dogs (82.1%) both a clinical and patholical diagnosis was made, in 20 dogs (13.8%) no pathological diagnosis could be made and in 6 dogs (4.1%) no clinical diagnosis was established. In the 119 dogs the agreement level between clinical and pathological diagnosis was scored by the referring veterinarian together with a pathologist. Total agreement was found in 61 cases (51.3%) and disagreement in 31 cases (26.0%). In the remaining cases (27=22.7%) the pathological diagnosis further specified the clinical diagnosis. Consecutive submission appeared difficult to achieve by the participating veterinarians. However, no major differences in agreement level was present between the veterinarian which succeeded in almost consecutive submissions and the other veterinarians. At necropsy 42 cases were diagnosed as neoplasia, of which 52.4% had been diagnosed clinically. As to infectious diseases 55.0% of these diseases diagnosed at necropsy had been diagnosed clinically. In about 20% of the cases the differences were of clinical significance according to the referring veterinarians. In addition, it was indicated by the clinicians that about 50% of the necropsies revealed findings which could amend future patient care. The results of the study stress the relevance of postmortem examination as crucial part of continuing education and of quality monitoring and assurance in veterinary medicine.


Assuntos
Autopsia/veterinária , Erros de Diagnóstico/veterinária , Doenças do Cão/diagnóstico , Patologia Clínica/normas , Animais , Autopsia/normas , Causas de Morte , Diagnóstico Diferencial , Erros de Diagnóstico/estatística & dados numéricos , Doenças do Cão/mortalidade , Doenças do Cão/patologia , Cães , Eutanásia Animal/estatística & dados numéricos , Feminino , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
Tijdschr Diergeneeskd ; 130(13): 407-8, 2005 Jul 01.
Artigo em Holandês | MEDLINE | ID: mdl-16047745

RESUMO

Since the introduction of AI, venereal diseases caused by Tritrichomonas fetus and Campylobacter fetus subsp. venerealis haved been eradicated in The Netherlands. Campylobacter fetus subsp. fetus can cause sporadic abortion and early embryonic death. When natural breeding is practised, venereal diseases must be included in the list of differential diagnoses of fertility problems. A case study of a Campylobacter fetus subsp. fetus infection is described.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter fetus , Doenças dos Bovinos/transmissão , Aborto Animal/microbiologia , Animais , Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/prevenção & controle , Infecções por Campylobacter/transmissão , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/prevenção & controle , Diagnóstico Diferencial , Feminino , Inseminação Artificial/veterinária , Países Baixos , Gravidez
13.
Psychoneuroendocrinology ; 59: 91-101, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26036454

RESUMO

BACKGROUND: Major depressive disorder (MDD) has been associated with low dehydroepiandrosterone-sulphate (DHEAS), - particularly relative to high cortisol - although conflicting findings exist. Moreover, it is unclear whether low DHEAS is only present during the depressive state, or manifests as a trait that may reflect vulnerability for recurrence. Therefore, we longitudinally tested whether low DHEAS and high cortisol/DHEAS-ratio in recurrent MDD (I) reflects a trait, and/or (II) varies with depressive state. In addition, we tested associations with (III) previous MDD-episodes, (IV) prospective recurrence, and (V) effects of cognitive therapy. METHODS: At study-entry, we cross-sectionally compared morning and evening salivary DHEAS and molar cortisol/DHEAS-ratio of 187 remitted recurrent MDD-patients with 72 matched controls. Subsequently, patients participated in an 8-week randomized controlled cognitive therapy trial. We repeated salivary measures after 3 months and 2 years. We measured clinical symptoms during a 10-year follow-up. RESULTS: Remitted patients showed steeper diurnal DHEAS-decline (p<.005) and a flatter diurnal profile of cortisol/DHEAS-ratio (p<.001) than controls. We found no state-effect in DHEAS or cortisol/DHEAS-ratio throughout follow-up and no association with number of previous episodes. Higher morning cortisol/DHEAS-ratio predicted shorter time till recurrence over the 10-year follow-up in interaction with the effects of cognitive therapy (p<.05). Finally, cognitive therapy did not influence DHEAS or cortisol/DHEAS-ratio. CONCLUSIONS: Diurnal profiles of DHEAS and cortisol/DHEAS-ratio remain equally altered in between depressive episodes, and may predict future recurrence. This suggests they represent an endophenotypic vulnerability trait rather than a state-effect, which provides a new road to understand recurrent depression and its prevention. TRIAL REGISTRATION: www.isrctn.com/ISRCTN68246470.


Assuntos
Sulfato de Desidroepiandrosterona/metabolismo , Transtorno Depressivo Maior/metabolismo , Hidrocortisona/metabolismo , Adulto , Estudos de Casos e Controles , Terapia Cognitivo-Comportamental , Estudos Transversais , Transtorno Depressivo Maior/terapia , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/metabolismo , Valor Preditivo dos Testes , Recidiva , Saliva/metabolismo , Resultado do Tratamento
14.
Artigo em Inglês | MEDLINE | ID: mdl-15041026

RESUMO

Major depressive disorders (MDD) and cardiovascular disease are mutually associated. They share signs and symptoms of the "metabolic syndrome". Two observations that may be causally related with the metabolic syndrome and therefore with both MDD and cardiovascular disease are a decrease in omega-3 polyunsaturated fatty acids (PUFAs) and a rise in plasma homocysteine (tHcy) levels. Both the rise in tHcy and the decrease in omega-3 PUFAs may be associated with enhanced lipid peroxidation. We exploratively studied 44 randomly chosen patients out of a cohort of 134 patients with the recurrent form of MDD (MDD-R). We measured tHcy levels together with saturated FAs, monounsaturated fatty acids (MUFAs) and PUFAs of the omega-3, omega-6 and omega-9 series in plasma and erythrocytes. Levels were compared with laboratory reference values. The main findings were a decrease in the erythrocytes of C22:5omega-3, C22:6omega-3, C24:1omega-9 and C20:3omega-9 and in the plasma a decrease in C24:1omega-9 and C20:3omega-9. The only significant association we found was between the total of omega-6 fatty acids and plasma tHcy. The FA alterations were found in patients although most of them were clinically recovered, suggesting that the alterations may represent a biological" trait" marker for recurrent depression.


Assuntos
Depressão/sangue , Ácidos Graxos/sangue , Homocisteína/sangue , Adulto , Estudos de Casos e Controles , Ácidos Graxos Insaturados/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Recidiva
15.
Vet Microbiol ; 44(2-4): 229-39, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-8588317

RESUMO

In the summer of 1990 an epizootic infection caused by a morbillivirus (DMV) killed several thousand striped dolphins (Stenella coeruleoalba) in the Mediterranean Sea. In 1991 and 1992 the epizootic reached Italian and Greek waters. The infection by DMV in the acute period of the epizootic caused encephalitis, pneumonia and depletion of lymph nodes. After 1990, the systemic infection apparently disappeared from the Catalonian coast, giving way to cases of chronic infection of the CNS. Dolphins that died between 1991 and May 1994 were necropsied, and investigated for lesions due to DMV, and for the presence of morbillivirus antigen in tissues. Encephalitis occurred in 6 dolphins in which DMV antigen was demonstrated in the CNS and which were without lesions or antigen in other, non-nervous tissues. Inflammatory lesions, gliosis, and DMV antigen decreased in density and amount from cerebral grey matter, through the thalamic areas to the medulla oblongata. The cerebellum was usually spared. Lesions consisted of non-suppurative encephalitis, with diffuse gliosis and glial nodules and neuronophagia, and loss of neurons. Perivascular cuffing of lymphocytes and plasma cells was present in the cerebral cortex and the white matter beneath the cortex. Multinucleate syncytia were not detected in any of the dolphins. The haemagglutinin of DMV was detected mainly in neurons in the cerebral cortical areas. There was no clear relationship between the presence and amount of DMV antigen and the density or chronicity of lesions. Viral inclusions were seen in haematoxylin and eosin stained sections in 3/6 dolphins, principally in the nucleus and the cytoplasm of neurons. In the immunoperoxidase stained sections, dense granular deposits of chromogen, similar to viral inclusions, were evident in all 6 dolphins. The change in the distribution of lesions and of DMV antigen, from systemic to localized in the CNS, and the clustering of systemic DMV infections in the first four months of the epizootic, giving rise to sporadic occurrence of local CNS infection in the subsequent four years, as well as the chronic nature of the CNS lesions, which closely resembles subacute sclerosing panencephalitis, strongly support the existence of a chronic morbillivirus infection in the striped dolphin, as a delayed consequence of the 1990 epizootic.


Assuntos
Surtos de Doenças/veterinária , Golfinhos/virologia , Infecções por Morbillivirus/veterinária , Animais , Encéfalo/patologia , Encéfalo/virologia , Doença Crônica , Feminino , Masculino , Infecções por Morbillivirus/epidemiologia , Infecções por Morbillivirus/patologia , Infecções por Morbillivirus/virologia
16.
Vet Microbiol ; 44(2-4): 251-9, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-8588319

RESUMO

Sequence analysis of the haemagglutinin protein (H) gene of the morbillivirus (PDV-2) isolated from a Siberian seal (Phoca sibirica) during the 1987/1988 epizootic in Lake Baikal revealed that it was most closely related to two recent isolates of canine distemper virus (CDV) from Germany and different from CDV vaccines currently in use in that region. The virus continued to circulate in seals in Lake Baikal after the 1987/1988 epizootic since sera collected from culled seals in the spring of 1992 were positive in morbillivirus ELISA tests, reacting most strongly with the CDV antigen.


Assuntos
Vírus da Cinomose Focina/genética , Hemaglutininas Virais/genética , Infecções por Morbillivirus/veterinária , Focas Verdadeiras/virologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/sangue , Surtos de Doenças/veterinária , Vírus da Cinomose Canina/genética , Vírus da Cinomose Canina/imunologia , Vírus da Cinomose Focina/imunologia , Feminino , Masculino , Dados de Sequência Molecular , Infecções por Morbillivirus/epidemiologia , Infecções por Morbillivirus/imunologia , Infecções por Morbillivirus/virologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sibéria/epidemiologia
17.
Vet Microbiol ; 23(1-4): 343-50, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2205971

RESUMO

During a recent disease outbreak among harbour seals (Phoca vitulina) in the North and Baltic seas, more than 17,000 animals have died. The clinical symptoms and pathological findings were similar to those of distemper in dogs. Based on a seroepizootiological study, using a canine distemper virus (CDV) neutralization assay, it was shown that CDV or a closely related morbillivirus (phocid distemper virus-PDV) was the primary cause of the disease. The virus was isolated in cell culture from the organs of dead seals and characterized as a morbillivirus by serology (immunofluorescence neutralization and enzyme-linked immunosorbent assays) and by negative contrast electron microscopy. Experimental infection of SPF dogs resulted in the development of mild clinical signs of distemper and CDV-neutralizing antibodies. The disease was reproduced in seals by experimental inoculation of organ material from animals that had died during the outbreak. However, seals that had been vaccinated with experimental inactivated CDV vaccines were protected against this challenge. This fulfilled the last of Koch's postulates, confirming that the morbillivirus isolated from the seal organs, was the primary cause of the disease outbreak. The recent demonstration of the presence of a similar virus in Lake Baikal seals (Phoca sibirica), which infected these Siberian seals 1 year before the northwestern European seals were infected, raises new questions about the origin of this infectious disease in pinnipeds.


Assuntos
Caniformia , Surtos de Doenças/veterinária , Paramyxoviridae/isolamento & purificação , Infecções por Respirovirus/veterinária , Focas Verdadeiras , Animais , Europa (Continente)/epidemiologia , Infecções por Respirovirus/epidemiologia , Infecções por Respirovirus/microbiologia , Infecções por Respirovirus/mortalidade
18.
Vet Immunol Immunopathol ; 37(3-4): 217-30, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8236799

RESUMO

In vitro assays were developed for studies concerning the functioning of the immune system of the harbour seal (Phoca vitulina). Proliferative responses of peripheral blood mononuclear cells (PBMC) were measured after stimulation with different concentrations of the mitogens concanavalin A (Con A), pokeweed mitogen (PWM), phytohaemagglutinin (PHA) or lipopolysaccharide from Salmonella typhimurium (LPS). Con A and PWM induced strong proliferative responses, while PHA and LPS induced comparatively low proliferative responses. Responses of mitogen stimulated PBMC to recombinant human interleukin-2 (rhIL-2) and in vitro immunoglobulin production by mitogen stimulated PBMC were measured to discriminate between stimulation of T cells and B cells. It was found that Con A and PHA stimulate phocine T cells, PWM stimulates both T cells and B cells and LPS predominantly stimulates phocine B cells. Antigen-specific immune responses were measured after immunization of seals with an inactivated rabies vaccine and/or with tetanus toxoid. Antigen-specific proliferation of PBMC and the presence of antigen-specific antibody forming cells were demonstrated for both antigens in the PBMC of immunized animals. The responses measured in vitro correlated well with the development of specific serum antibody titers to these antigens.


Assuntos
Linfócitos B/imunologia , Focas Verdadeiras/imunologia , Linfócitos T/imunologia , Animais , Células Produtoras de Anticorpos/imunologia , Antígenos/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Sistema Imunitário , Imunização , Leucócitos Mononucleares/imunologia , Ativação Linfocitária , Masculino , Mitógenos/imunologia , Vacina Antirrábica/imunologia , Toxoide Tetânico/imunologia
19.
Vet Immunol Immunopathol ; 42(3-4): 331-48, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7810064

RESUMO

The immune system of many mammalian species is not fully developed at birth, with newborns obtaining temporary immunological protection from maternal antibodies. Little is known of the immune system of the harbour seal, and developmental aspects of its immune system have not been systematically studied. We collected blood and milk samples from nine free-ranging mother-pup pairs throughout the lactation period on Sable Island, Canada, in an effort to characterise developmental aspects of the immune system of this newborn pinniped. Pup lymphocytes responded stronger to the mitogens concanavalin A, phytohaemagglutinin, and pokeweed mitogen than the lymphocytes of their mothers. In contrast to newborn cats and dogs, newborn seal pups developed high specific antibody responses after immunisation with an inactivated rabies vaccine. Circulating levels of total IgG in newborn pups were low (3% of maternal levels), but increased rapidly after colostrum intake (to 65% of maternal levels after 15 days). A similar pattern of increase in pup serum was observed for phocine distemper virus specific antibodies which had been detected in the serum and milk of mothers, suggesting that the transfer of colostral antibodies is an important feature of temporary protection for the pup. We speculate that the relative immunocompetence of the harbour seal at birth reflects an adaptation to its relatively short nursing period and limited maternal care.


Assuntos
Animais Recém-Nascidos/imunologia , Imunocompetência , Focas Verdadeiras/imunologia , Animais , Anticorpos Antivirais/análise , Vírus da Cinomose Canina/imunologia , Imunidade Materno-Adquirida/imunologia , Imunoglobulina G/análise , Ativação Linfocitária/imunologia , Linfócitos/imunologia , Leite/imunologia , Morbillivirus/imunologia , Vacina Antirrábica/imunologia
20.
J Vet Diagn Invest ; 9(2): 180-5, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9211238

RESUMO

Eighty bovine fetuses with confirmed neosporosis were used to score lesion severity and presence of parasites in brain, heart, and liver. A comparison was made between epizootic and sporadic abortion cases. The possible influence of fetal age was also investigated. Histologic lesions of multifocal encephalitis, myocarditis, and periportal hepatitis with or without focal hepatocellular necrosis were almost always observed. Neospora caninum tachyzoites were identified immunohistochemically in 85% of the brains, 14% of the hearts, and 26% of the livers. Tissue cysts were observed in 21% of the brains. Significant differences between epizootic and sporadic abortion cases were found only in the liver. Hepatic lesions were more prominent and N. caninum tachyzoites were observed more frequently and in higher numbers in epizootic cases. Examination by immunohistochemistry of the liver in addition to the brain can be highly contributive diagnostically, particularly in epizootic cases. There were no significant age-related differences except for a higher presence of tachyzoites in the hearts of younger fetuses (3-4 months gestational age).


Assuntos
Aborto Animal/parasitologia , Doenças dos Bovinos , Coccidiose/veterinária , Neospora , Aborto Animal/epidemiologia , Aborto Animal/patologia , Animais , Anticorpos Antiprotozoários/sangue , Encéfalo/embriologia , Encéfalo/parasitologia , Encéfalo/patologia , Bovinos , Coccidiose/embriologia , Coccidiose/epidemiologia , Coccidiose/patologia , Surtos de Doenças/veterinária , Feminino , Feto , Idade Gestacional , Coração/embriologia , Coração/parasitologia , Fígado/embriologia , Fígado/parasitologia , Fígado/patologia , Miocárdio/patologia , Países Baixos/epidemiologia , Gravidez
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