Patterns of neuronal activation in the rat brain and spinal cord in response to increasing durations of restraint stress

By most accounts the psychological stressor restraint produces a distinct pattern of neuronal activation in the brain. However, some evidence is incongruous with this pattern, leading us to propose that the restraint- induced pattern in the central nervous system might depend on the duration of restraint used. We therefore determined the pattern of neuronal activation ( as indicated by the presence of Fos protein) seen in the paraventricular nucleus (PVN), bed nucleus of the stria terminalis, amygdala, locus coeruleus, nucleus tractus solitarius (NTS), ventrolateral medulla (VLM) and thoracic spinal cord of the rat in response to 0, 15, 30 or 60 min periods of restraint. We found that although a number of cell groups displayed a linear increase in activity with increasing durations of restraint ( e. g. hypothalamic corticotrophin-releasing factor (CRF) cells, medial amygdala neurons and sympathetic preganglionic neurons of the thoracic spinal cord), a number of cell groups did not. For example, in the central amygdala restraint produced both a decrease in CRF cell activity and an increase in non-CRF cell activity. In the locus coeruleus, noradrenergic neurons did not display Fos in response to 15 min of restraint, but were significantly activated by 30 or 60 min restraint. After 30 or 60 min restraint a greater degree of activation of more rostral A1 noradrenergic neurons was observed compared with the pattern of A1 noradrenergic neurons in response to 15 min restraint. The results of this study demonstrate that restraint stress duration determines the amount and the pattern of neuronal activation seen in response to this psychological stressor.

Developmental vitamin D (DVD) deficiency in the rat alters adult behaviour independently of HPA function

Developmental vitamin D deficiency (DVD) has been shown to alter the orderly pattern of brain development. Even though the period of vitamin D deficiency is restricted to gestation this is sufficient to induce behavioural abnormalities in the adult offspring consistent with those seen in many animal models of schizophrenia. Given that some of these behavioural alterations could also be an indirect result of either impaired maternal hypothalamic pituitary axis (HPA) function (which in turn could influence maternal care) or the result of a permanent alteration in HPA function in the adult offspring we have examined HPA status in both maternal animals and adult offspring. In this study we have established that HPA function is normal in the maternally vitamin D deficient rat. We replicate the behavioural phenotype of hyperlocomotion whilst establishing that HPA function is also unchanged in the adult mate offspring. We conclude that the behavioural alterations induced by DVD deficiency are due to some adverse event in brain development rather than via an alteration in stress response. (c) 2006 Elsevier Ltd. All rights reserved.

A spirochete isolated from a case of severe virulent ovine foot disease is closely related to a Treponeme isolated from human periodontitis and bovine digital dermatitis

The isolation of spirochetes from severe ovine foot disease has been reported recently by our research group. In this study we describe the preliminary classification of this spirochete based on nucleotide sequence analysis of the PCR-amplified 16S rRNA gene. Phylogenetic analysis of this sequence in comparison with other previously reported 16S rRNA gene sequences showed that the spirochete belonged to the treponemal phylotype Treponema vincentii which has been associated with bovine digital dermatitis and human periodontal disease. Further work is required to define the common virulence determinants of these closely related treponemes in the aetiology of these tissue destructive diseases.

La comunicación como base en la seguridad del paciente

Presentamos el caso de un paciente que, como secuela de un accidente cerebrovascular, presenta afasia. Tanto la enfermería como el médico de familia tenían graves problemas de comunicación, por lo que se realizó un pictograma para mejorar la fluidez entre el paciente y los sanitarios. Tras familiarizarse con él, facilitó mucho la adecuada y correcta comunicación bidireccional y mejoró la seguridad de los cuidados.

Urticaria acuagénica

Presentamos el caso de una mujer de 30 años con urticaria acuagénica; también su madre presenta el mismo diagnóstico. La urticaria acuagénica es una forma rara de urticaria física que cursa con habones que afectan generalmente la parte superior del cuerpo. Es importante hacer diagnóstico diferencial con otros tipos de urticaria. La etiopatogenia no está clara. Los antihistamínicos mejoran la clínica.

Torsade de pointes

Presentamos el caso de un varón tratado por convulsiones con diazepam en varias ocasiones. Finalmente se demuestra un síndrome de QT largo adquirido que le predisponía a torsades de pointes manifestándose con convulsiones y, por tanto, tratado erróneamente. Se repasa el síndrome del QT largo, describiendo las diferentes causas tanto congénitas como adquiridas, diagnóstico electrocardiográfico, la medición corregida del intervalo QT según la frecuencia cardiaca y tratamiento.