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1.
J Dev Phys Disabil ; 35(3): 353-373, 2023.
Article in English | MEDLINE | ID: mdl-35789590

ABSTRACT

Using telehealth as a mode of service delivery has the potential to address some long-standing challenges in early intervention (EI) services such as waiting lists to access services. Yet, little is known about parent perceptions of telehealth in EI based on their lived experiences partnering with EI practitioners. The purpose of this study was to explore parent perceptions on using telehealth, especially on family-professional partnerships and coaching. Interviews were conducted with 15 parents of children receiving EI services via telehealth from June to August of 2021. Almost half of the participants reflected under-represented racial and ethnic backgrounds. Constant comparative analysis and emergent coding were used for data analysis. The findings showed that the advantages outnumbered the disadvantages regarding telehealth. Participants reported that telehealth provided a safe and flexible option and eliminated the wait to access EI services. However, participants identified some disadvantages to telehealth including telehealth precluded substantive interactions with therapists and limited access to technology. The findings also indicated that telehealth enhanced family-professional partnerships. Nearly all participants valued coaching during telehealth. Participants suggested initial supports to facilitate EI via telehealth, including stable internet access, telehealth training, and an initial in-person visit. Implications for research and practice are discussed. Supplementary Information: The online version contains supplementary material available at 10.1007/s10882-022-09853-w.

2.
J Small Anim Pract ; 62(11): 973-978, 2021 11.
Article in English | MEDLINE | ID: mdl-34254309

ABSTRACT

OBJECTIVES: To assess the correlation between gallbladder wall thickness and serum/plasma albumin concentrations in dogs. MATERIALS AND METHODS: Retrospective searches of digital medical record databases were conducted to identify dogs that had either severely low serum/plasma albumin concentration (<1.5 g/dL) or ultrasonographic evidence of gallbladder wall thickening (>2 mm). Analysis of covariance models were used to analyze gallbladder wall thickness with sample type (serum vs plasma), age, etiology, albumin, and albumin ' etiology as the covariates. RESULTS: A total of 216 dogs met inclusion criteria. One-hundred and forty-six dogs had a thickened gallbladder wall (Group 1). Median serum/plasma albumin concentration for dogs in this group was 2.2 g/dL (1 to 5 g/dL), and 84 dogs (57.5%) had hypoalbuminemia (<2.5 g/dL). The search for dogs with severe hypoalbuminemia (< 1.5 g/dL) identified 70 dogs (Group 2). In this group, median gallbladder wall thickness was 1.3 mm (0.2 to 6.1 mm) and 17 dogs (24.3%) had a thickened gallbladder wall. Serum/plasma albumin concentration and gallbladder wall thickness were not significantly correlated for Group 1 (r = 0.0044, p = 0.9580) or Group 2 (r = -0.1137, p = 0.3487). A moderate negative correlation (-0.64) was identified between gallbladder wall thickness and albumin concentration in dogs with immune-mediated diseases (p = 0.03). CLINICAL SIGNIFICANCE: Gallbladder wall thickness and serum/plasma albumin concentration are independent variables in dogs.


Subject(s)
Dog Diseases , Hypoalbuminemia , Animals , Dog Diseases/diagnostic imaging , Dogs , Gallbladder/diagnostic imaging , Hypoalbuminemia/veterinary , Retrospective Studies , Serum Albumin , Ultrasonography/veterinary
3.
Int Emerg Nurs ; 43: 106-112, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30733005

ABSTRACT

AIM: Sepsis is a significant and time-sensitive clinical concern for patients who present to Emergency Departments (EDs). Existing guidelines do not define nurses' roles in managing sepsis. This study explored ED nurses' experiences and perceptions around recognising and responding to patients with sepsis, and their awareness of sepsis screening and prognostic tools. The knowledge and insights gained from this study may be used to inform local and international ED policies, and enrich nursing educational packages that may be used to improve quality of patient care and patient outcomes. METHODS: Qualitative design incorporating semi-structured interviews with 14 ED nurses was undertaken. Thematic and consensus-based content analyses were used to explore transcripts. FINDINGS: Six key themes were identified; (1) contribution of the organisation, (2) appreciation of knowledge, (3) appreciation of clinical urgency, (4) appreciation of importance of staff supervision, (5) awareness of the importance of staff experience, and (6) awareness of the need to seek advice. CONCLUSION: ED nurses' identified deficits in their capacity to recognise and respond to patients with sepsis, despite their vital role within the multidisciplinary team that cares for patients with sepsis. The knowledge and insights gained from this study can be used to inform ED policies, to enrich context-specific educational packages that aim to improve quality of patient care and outcomes and identify areas for further research. Development and implementation of a nurse-inclusive sepsis pathway may address many deficits identified in this study.


Subject(s)
Emergency Nursing/standards , Nurse's Role/psychology , Sepsis/nursing , Adolescent , Adult , Child , Child, Preschool , Clinical Competence/standards , Emergency Nursing/statistics & numerical data , Emergency Service, Hospital/organization & administration , Female , Humans , Infant , Interviews as Topic/methods , Male , Qualitative Research , Queensland
4.
Eur J Appl Physiol ; 118(10): 2171-2177, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30043183

ABSTRACT

PURPOSE: Compression socks are frequently used in the treatment and prevention of lower-limb pathologies; however, when combined with endurance-based exercise, the impact of compression socks on haemostatic activation remains unclear. OBJECTIVES: To investigate the effect of wearing compression socks on coagulation and fibrinolysis following a marathon. METHODS: Sixty-seven participants [43 males (mean ± SD: age: 46.7 ± 10.3 year) and 24 females (age: 40.0 ± 11.0 year)] were allocated into a compression (SOCK, n = 34) or control (CONTROL, n = 33) group. Venous blood samples were obtained 24 h prior to and immediately POST-marathon, and were analyzed for thrombin-anti-thrombin complex (TAT), tissue factor (TF), tissue factor pathway inhibitor (TFPI), and D-Dimer. RESULTS: Compression significantly attenuated the post-exercise increase in D-Dimer compared to the control group [median (range) SOCK: + 9.02 (- 0.34 to 60.7) ng/mL, CONTROL: + 25.48 (0.95-73.24) ng/mL]. TF increased following the marathon run [median (range), SOCK: + 1.19 (- 7.47 to 9.11) pg/mL, CONTROL: + 3.47 (- 5.01 to 38.56) pg/mL] in all runners. No significant post-exercise changes were observed for TAT and TFPI. CONCLUSIONS: While activation of coagulation and fibrinolysis was apparent in all runners POST-marathon, wearing compression socks was shown to reduce fibrinolytic activity, as demonstrated by lower D-Dimer concentrations. Compression may reduce exercise-associated haemostatic activation when completing prolonged exercise.


Subject(s)
Endurance Training , Fibrinolysis , Running/physiology , Stockings, Compression , Adult , Female , Healthy Volunteers , Humans , Male , Middle Aged
5.
Breast Cancer Res ; 20(1): 42, 2018 05 19.
Article in English | MEDLINE | ID: mdl-29778097

ABSTRACT

BACKGROUND: Psychiatric medications are widely prescribed in the USA. Many antipsychotics cause serum hyperprolactinemia as an adverse side effect; prolactin-Janus kinase 2 (JAK2)-signal transducer and activator of transcription 5 (STAT5) signaling both induces cell differentiation and suppresses apoptosis. It is controversial whether these antipsychotics increase breast cancer risk. METHODS: We investigated the impact of several antipsychotics on mammary tumorigenesis initiated by retrovirus-mediated delivery of either ErbB2 or HRas or by transgenic expression of Wnt-1. RESULTS: We found that the two hyperprolactinemia-inducing antipsychotics, risperidone and pimozide, prompted precancerous lesions to progress to cancer while aripiprazole, which did not cause hyperprolactinemia, did not. We observed that risperidone and pimozide (but not aripiprazole) caused precancerous cells to activate STAT5 and suppress apoptosis while exerting no impact on proliferation. Importantly, we demonstrated that these effects of antipsychotics on early lesions required the STAT5 gene function. Furthermore, we showed that only two-week treatment of mice with ruxolitinib, a JAK1/2 inhibitor, blocked STAT5 activation, restored apoptosis, and prevented early lesion progression. CONCLUSIONS: Hyperprolactinemia-inducing antipsychotics instigate precancerous cells to progress to cancer via JAK/STAT5 to suppress the apoptosis anticancer barrier, and these cancer-promoting effects can be prevented by prophylactic anti-JAK/STAT5 treatment. This preclinical work exposes a potential breast cancer risk from hyperprolactinemia-inducing antipsychotics in certain patients and suggests a chemoprevention regime that is relatively easy to implement compared to the standard 5-year anti-estrogenic treatment in women who have or likely have already developed precancerous lesions while also requiring hyperprolactinemia-inducing antipsychotics.


Subject(s)
Breast Neoplasms/genetics , Janus Kinase 2/genetics , Precancerous Conditions/genetics , STAT5 Transcription Factor/genetics , Animals , Antipsychotic Agents/adverse effects , Apoptosis/drug effects , Breast/drug effects , Breast/pathology , Breast Neoplasms/chemically induced , Breast Neoplasms/epidemiology , Breast Neoplasms/pathology , Cell Differentiation/drug effects , Female , Humans , Hyperprolactinemia/chemically induced , Hyperprolactinemia/epidemiology , Hyperprolactinemia/genetics , Hyperprolactinemia/pathology , Mice , Pimozide/adverse effects , Precancerous Conditions/chemically induced , Precancerous Conditions/pathology , Risk Factors , Risperidone/adverse effects , Signal Transduction/drug effects
6.
Nurse Educ Today ; 54: 56-61, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28477564

ABSTRACT

BACKGROUND: Objective structured clinical examinations (OSCEs) are designed to assess clinical skill performance and competency of students in preparation for 'real world' clinical responsibilities. OSCEs are commonly used in health professional education and are typically associated with high levels of student anxiety, which may present a significant barrier to performance. Students, including nursing students, have identified that flexible access to exemplar OSCEs might reduce their anxiety and enable them to better prepare for such examinations. AIM: To implement and evaluate an innovative approach to preparing students for OSCEs in an undergraduate (registration) acute care nursing course. METHOD: A set of digitized OSCE exemplars were prepared and embedded in the University-based course website as part of usual course learning activities. Use of the exemplars was monitored, pre and post OSCE surveys were conducted, and qualitative data were collected to evaluate the approach. OSCE grades were also examined. FINDINGS: The online OSCE exemplars increased self-rated student confidence, knowledge, and capacity to prepare and provided clarity around assessment expectations. OSCE exemplars were accessed frequently and positively received; but did not impact on performance. CONCLUSION: Video exemplars aid student preparation for OSCEs, providing a flexible, innovative and clear example of the assessment process. Video exemplars improved self-rated student confidence and understanding of performance expectations, leading to increased engagement and reduced anxiety when preparing for the OSCE, but not overall OSCE performance. Such OSCE exemplars could be used to increase staff capacity and improve the quality of the student learning experience.


Subject(s)
Clinical Competence , Educational Measurement/standards , Simulation Training/methods , Students, Nursing/psychology , Education, Nursing, Baccalaureate , Educational Measurement/methods , Humans
7.
J Small Anim Pract ; 57(3): 148-58, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26931500

ABSTRACT

OBJECTIVE: The objective of this study was to examine the utility of capsule endoscopy to detect mucosal abnormalities in dogs with gastrointestinal haemorrhage. METHODS: Capsules were administered to 2 healthy controls and 8 patients with gastrointestinal haemorrhage. Images were evaluated for quality, gastric emptying time, small intestinal transit time and presence of lesions. RESULTS: There were no adverse effects of capsule endoscopy in dogs weighing from 7·7 to 58 kg. The capsule traversed the entire gastrointestinal tract in 5 of 8 patients, with high quality images obtained in the stomach and small intestine. Gastric emptying time and small intestinal transit time ranged from 1 to 270 and 15 to 180 minutes, respectively. In 3 of 8 patients, the capsule remained in the stomach despite pro-kinetics. Gastric lesions included mild haemorrhage and pinpoint erosion (4 of 8), a mass (1) and thickened bleeding pyloric mucosa (2). Two of 3 dogs with capsule retention had gastric lesions. Intestinal lesions included a healing duodenal ulcer, abnormal villi, ileal ulceration and colonic bleeding. Lesions identified by capsule endoscopy were considered a significant source of haemorrhage in 4 of 7 dogs with active bleeding. The relevance of pinpoint gastric mucosal erosions to blood loss is unclear. CLINICAL SIGNIFICANCE: Capsule endoscopy can enable the non-invasive detection of gastric and small intestinal mucosal lesions in dogs presenting for evaluation of gastrointestinal bleeding.


Subject(s)
Capsule Endoscopy/veterinary , Gastrointestinal Hemorrhage/veterinary , Intestinal Mucosa/pathology , Animals , Dogs , Female , Gastrointestinal Hemorrhage/pathology , Male
8.
Oncogene ; 35(11): 1461-7, 2016 Mar 17.
Article in English | MEDLINE | ID: mdl-26096929

ABSTRACT

In the normal mammary gland, the basal epithelium is known to be bipotent and can generate either basal or luminal cells, whereas the luminal epithelium has not been demonstrated to contribute to the basal compartment in an intact and normally developed mammary gland. It is not clear whether cellular heterogeneity within a breast tumor results from transformation of bipotent basal cells or from transformation and subsequent basal conversion of the more differentiated luminal cells. Here we used a retroviral vector to express an oncogene specifically in a small number of the mammary luminal epithelial cells and tested their potential to produce basal cells during tumorigenesis. This in-vivo lineage-tracing work demonstrates that luminal cells are capable of producing basal cells on activation of either polyoma middle T antigen or ErbB2 signaling. These findings reveal the plasticity of the luminal compartment during tumorigenesis and provide an explanation for cellular heterogeneity within a cancer.


Subject(s)
Breast Neoplasms/pathology , Cell Plasticity/physiology , Epithelial Cells/cytology , Mammary Glands, Human/cytology , Antigens, Viral, Tumor/metabolism , Cell Lineage/physiology , Cell Proliferation/physiology , Cell Transformation, Neoplastic/pathology , Female , Humans , Receptor, ErbB-2/metabolism , Signal Transduction/physiology
9.
Aust Nurs Midwifery J ; 24(4): 41, 2016 10.
Article in English | MEDLINE | ID: mdl-29249100

ABSTRACT

Mental health is an increasing component of the burden of disease worldwide, providing challenges in healthcare and health systems (World Health Organization, 2013); it is widespread, and not limited to dedicated mental health facilities.


Subject(s)
Education, Nursing/trends , Emergency Nursing/education , Mental Disorders/nursing , Simulation Training , Acute Disease , Focus Groups , Humans , Queensland
10.
Nurse Educ Pract ; 15(6): 415-20, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26027548

ABSTRACT

Anatomy and Physiology is a core course in pre-registration nursing programs, yet many students have difficulty successfully negotiating the large volume of content and the complex concepts in these bioscience courses. Typically students perform poorly in these 'threshold' courses', despite multiple interventions to support student engagement. Investigation of the shortcomings in these courses, based on feedback from students indicated several key areas of difficulty in the course, especially focused around a relative lack of hands-on 'concrete' activities in laboratories and tutorials. To attempt to address this, academic and technical staff developed activities for students that promoted discussion and allowed students to interact easily and repetitively with content. Interactive tables and posters that needed to be labelled or 'filled-in' using pre-prepared Velcro dots, as well as pre-prepared flash cards to promote group work, were some examples of the activities used to enhance student experiences and promote hands-on learning. Over the academic year of 2013 these activities were introduced into the laboratory and tutorial classes for first year Bachelor of Nursing anatomy and physiology students. Staff and student participants positively rated implementation of these new activities on surveys, as they allowed them to explore the difficult aspects of anatomy and physiology, utilising various learning styles that may have been neglected in the past.


Subject(s)
Anatomy/education , Education, Nursing, Baccalaureate , Learning , Physiology/education , Students, Nursing/psychology , Teaching/methods , Attitude of Health Personnel , Curriculum , Humans , Nursing Education Research , Problem-Based Learning , Surveys and Questionnaires
11.
Transl Psychiatry ; 2: e118, 2012 May 22.
Article in English | MEDLINE | ID: mdl-22832962

ABSTRACT

The presence of olfactory dysfunction in individuals at higher risk of Alzheimer's disease has significant diagnostic and screening implications for preventive and ameliorative drug trials. Olfactory threshold, discrimination and identification can be reliably recorded in the early stages of neurodegenerative diseases. The current study has examined the ability of various olfactory functions in predicting cognitive decline in a community-dwelling sample. A group of 308 participants, aged 46-86 years old, were recruited for this study. After 3 years of follow-up, participants were divided into cognitively declined and non-declined groups based on their performance on a neuropsychological battery. Assessment of olfactory functions using the Sniffin' Sticks battery indicated that, contrary to previous findings, olfactory discrimination, but not olfactory identification, significantly predicted subsequent cognitive decline (odds ratio = 0.869; P<0.05; 95% confidence interval = 0.764-0.988). The current study findings confirm previously reported associations between olfactory and cognitive functions, and indicate that impairment in olfactory discrimination can predict future cognitive decline. These findings further our current understanding of the association between cognition and olfaction, and support olfactory assessment in screening those at higher risk of dementia.


Subject(s)
Alzheimer Disease/diagnosis , Discrimination, Psychological , Olfaction Disorders/diagnosis , Smell , Aged , Aged, 80 and over , Agnosia/diagnosis , Agnosia/psychology , Alzheimer Disease/genetics , Alzheimer Disease/psychology , Apolipoprotein E4/genetics , Apolipoproteins E/genetics , Cohort Studies , Disease Progression , Female , Genotype , Humans , Independent Living/psychology , Longitudinal Studies , Male , Middle Aged , Neuropsychological Tests/statistics & numerical data , Odorants , Olfaction Disorders/psychology , Predictive Value of Tests , Psychometrics , Recognition, Psychology , Sensory Thresholds
12.
J Vet Intern Med ; 25(2): 169-86, 2011.
Article in English | MEDLINE | ID: mdl-21382073

ABSTRACT

Portal hypertension (PH) is the result of increased vascular resistance in the portal circulation, increased portal venous blood flow, or both. In veterinary medicine, where portal pressure is seldom measured directly, the diagnosis of PH often is inferred from identification of associated complications including multiple acquired portosystemic shunts, ascites, and hepatic encephalopathy. Likewise, treatment of PH primarily is aimed at controlling these complications. The goal of this review is to provide an update on the pathophysiology, diagnosis, and treatment of PH. The review draws from information in the veterinary hepatology literature, reviews, and consensus statements in human hepatology and the literature on experimental models of PH.


Subject(s)
Cat Diseases/diagnosis , Cat Diseases/therapy , Dog Diseases/diagnosis , Dog Diseases/therapy , Hypertension, Portal/veterinary , Animals , Cats , Dogs , Hypertension, Portal/complications , Hypertension, Portal/diagnosis , Hypertension, Portal/therapy , Liver/blood supply , Liver/pathology , Liver Circulation/physiology , Portal System/anatomy & histology , Portal System/physiology
13.
Neurobiol Learn Mem ; 93(2): 268-74, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19879368

ABSTRACT

Mice can learn a food preference from odor cues transmitted on the breath of a conspecific, even if the "demonstrator" is anesthetized. To our knowledge there are no studies examining the effect of anesthetizing the "observer" on development of memory for socially transmitted food preferences (STFP). In Experiment 1 we found that 2-4 month-old F2 C57Bl/6x129sv male and female mice demonstrated a STFP after a 5min exposure to an anesthetized demonstrator mouse when tested 24h later. In Experiment 2, observer mice anesthetized with Sagatal (60 mg/kg) prior to the "social interaction" preferentially avoided the cued food when tested 24h later. This aversion was not due to any overt aversive effects of this dose of Sagatal because mice that ate the food and were then anesthetized, or could only smell the food for 5 min while anesthetized, showed no preference or aversion. In a third experiment we found that the Sagatal-induced aversion was not a general property of anesthesia because there were varied results produced by observer mice treated with anesthetic drugs with different mechanisms of action. Vetalar (200mg/kg) and Rompun (10 mg/kg) treated animals ate similar amounts of cued and non-cued food at test, indicating an absence of learning. Hypnorm (0.5 ml/kg) treated animals showed a preference for the cued food whereas those treated with Hypnovel (2.5 ml/kg) showed an aversion to the cued food. These results show that the food aversion observed with Sagatal is not a general property of anesthetic agents, but appears to be restricted to those acting primarily on the GABAergic system. Thus, we have shown that under certain conditions it is possible for an anesthetized observer mouse to learn a preference or aversion of a socially-linked olfactory cue.


Subject(s)
Anesthetics/pharmacology , Central Nervous System Agents/pharmacology , Food Preferences/drug effects , Memory/drug effects , Olfactory Perception/drug effects , Social Behavior , Animals , Butyrophenones/pharmacology , Cues , Drug Combinations , Female , Fentanyl/pharmacology , Male , Mice , Mice, Inbred C57BL , Neuropsychological Tests , Pentobarbital/pharmacology , Time Factors , Xylazine/pharmacology
14.
Parkinsonism Relat Disord ; 15(7): 490-4, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19138875

ABSTRACT

Previous data on the prevalence of olfactory dysfunction in Parkinson's disease (PD) range from 45% to 90%. The present multicenter study aimed to provide data on the prevalence of smell loss in a large sample of PD patients from three independent populations. Olfactory sensitivity was tested in 400 patients from Australia, Germany, and The Netherlands by means of a psychophysical olfactory test, the "Sniffin' Sticks", which is comprised of 3 subtests of olfactory function. Out of the total number of patients 45.0% presented as functionally anosmic, 51.7% were hyposmic, whereas only 3.3% were normosmic. This indicates that 96.7% of PD patients present with significant olfactory loss when compared to young normosmic subjects. This figure falls to 74.5%, however, when adjusted to age-related norms. Thus, olfactory dysfunction should be considered as a reliable marker of the disease.


Subject(s)
Odorants , Olfaction Disorders/epidemiology , Olfaction Disorders/etiology , Parkinson Disease/complications , Parkinson Disease/epidemiology , Adult , Age Factors , Aged , Aged, 80 and over , Analysis of Variance , Female , Humans , Male , Middle Aged , Olfaction Disorders/diagnosis , Parkinson Disease/classification , Prevalence , Psychophysics , Sex Factors , Statistics as Topic
15.
Behav Brain Res ; 177(1): 61-9, 2007 Feb 12.
Article in English | MEDLINE | ID: mdl-17147959

ABSTRACT

Chicks searching for food grains against a background of unfamiliar pebbles usually peck pebbles less when using the right eye (RE), or both eyes, than when using the left eye (LE), provided that the embryo's RE has been exposed to light (Li), as is normal. When pecking is fast this right/left difference is mainly due to a heightened ability of RE chicks to inhibit premature pecks (and inappropriate responses in general). Dark incubation (Da) abolishes this ability in RE chicks, and RE and LE chicks show similar frequent pebble pecks. We show now that, under conditions that cause cautious pecking, both Li and Da chicks show a new effect: in both cases LE chicks peck pebbles more than RE chicks, probably because of the novelty of pebbles. Interest in novelty in LE chicks is known to be unaffected by light in incubation. Age-dependent effects are also important. RE and LE chicks, which had either the LE or RE exposed to light before hatching, were tested on days 3, 5, 8 or 12 post-hatching, under conditions giving normal fast pecking. Artificial exposure of the embryo's LE to light reversed the lateralization: in general, chicks using the light-exposed eye performed well at all ages. Irrespective of which eye system had heightened ability to inhibit pebble pecks, RE performance differed from usual on 2 days, whereas LE chicks showed no age-dependent changes. Changes confined to the RE system, therefore, affect behaviour independently of lateralization of the ability to inhibit inappropriate response.


Subject(s)
Appetite/physiology , Behavior, Animal/physiology , Discrimination Learning/physiology , Functional Laterality/physiology , Light , Visual Perception/physiology , Age Factors , Animals , Animals, Newborn , Appetite/radiation effects , Chick Embryo , Cues , Edible Grain , Photic Stimulation/methods , Reaction Time/physiology , Time Factors , Visual Perception/radiation effects
16.
Neuroscience ; 109(2): 243-51, 2002.
Article in English | MEDLINE | ID: mdl-11801361

ABSTRACT

We report the presence of dehydroepiandosterone (DHEA) and DHEA sulphate (DHEA-S) in the day-old-chick brain, and their possible role in memory formation. DHEA and DHEA-S were present in the brain at higher concentrations than in the plasma. Radioimmunoassay examination of the intermediate medial hyperstriatum ventrale 5 or 30 min after training or the lobus parolfactorius 60 or 120 min after training on the passive avoidance task did not show learning-related differences in absolute levels of DHEA or DHEA-S. However, bilateral intracerebral injections of DHEA or DHEA-S before or after training on the weak passive avoidance task enhanced recall 24 h after training. Memory retention was enhanced by administration of DHEA and DHEA-S 15 min before training or 30 and 60 but not 180 min after training. Neurosteroids are present in high concentrations in regions of the chick brain known to be associated with learning and memory for an aversive one-trial task. Our study demonstrates that memory retention for this task is enhanced by administration of the neurosteroids DHEA-S and DHEA. These findings provide additional evidence that these neurosteroids have memory-enhancing properties and, thus, if common to other tasks and species, that DHEA-S and DHEA may constitute potential therapeutic tools for the treatment of cognitive deficits.


Subject(s)
Aging/drug effects , Avoidance Learning/drug effects , Chickens/growth & development , Dehydroepiandrosterone Sulfate/blood , Dehydroepiandrosterone/blood , Memory/drug effects , Telencephalon/drug effects , Telencephalon/growth & development , Aging/metabolism , Animals , Animals, Newborn , Avoidance Learning/physiology , Brain/drug effects , Brain/metabolism , Chickens/metabolism , Dehydroepiandrosterone/pharmacology , Dehydroepiandrosterone Sulfate/pharmacology , Dose-Response Relationship, Drug , Female , Male , Memory/physiology , Sex Characteristics , Telencephalon/metabolism , Time Factors
17.
Appl Anim Behav Sci ; 73(4): 267-279, 2001 Aug 27.
Article in English | MEDLINE | ID: mdl-11434961

ABSTRACT

The domestic pig, Sus scrofa, builds a maternal nest in the day before parturition. A model for porcine nest building has been established, in which exogenously administered prostaglandin (PG)F(2alpha) is used to induce nesting behaviour in cyclic, pseudopregnant and pregnant pigs. This experiment was designed to examine the effect of PGF(2alpha) on the preferences of non-pregnant gilts for pens bedded with straw compared with bare pens. Ten 6-month-old nulliparous female pigs (gilts) were tested in an arena, which consisted of four pens (1.8mx1.7m), a neutral area (1.5mx3.4m) and a start area (1.5mx3.4m). Two of the pens contained 2kg of fresh straw and the remainder of the testing arena was devoid of straw. On the first day of testing half of the pigs were given a control intramuscular injection of 3ml 0.9% saline and the remainder were given an intramuscular injection of 15mg PGF(2alpha) and their behaviour scored for 1h after treatment. On the following day the treatments were reversed, such that each pig was given both treatments (saline or PGF(2alpha)). There was no significant effect of the order of treatment on behaviour. After saline-treatment the pigs spent most of their time in the pens containing straw (59%) and the least amount of time in bare pens (5%). In the straw pens, saline-treatment induced bouts of oronasal contact with straw of a relatively long duration (11-100s), which we interpret as foraging. In the hour after PGF(2alpha)-treatment the pigs also spent most of their time in the pens containing straw (44%) and the least amount of time in bare pens (10%), but they interacted with the straw in a markedly different way. PGF(2alpha)-treated pigs displayed bouts of oronasal contact with straw of a relatively short duration (2-10s) which, together with high frequencies of pawing at straw, lifting and carrying straw in the mouth, we interpret as nest building behaviour. Superimposed on this is the finding that gilts spend more time in the neutral areas after PGF(2alpha)-treatment than they did after saline-treatment. PGF(2alpha)-treated pigs spent most of their time engaged in nesting behaviour within the straw pens but they also gathered and deposited straw in different areas of the test arena (neutral and start areas); behaviours not seen after saline-treatment. We conclude that pigs generally prefer a pen containing straw bedding to a bare pen but that PGF(2alpha) alters the way they interact with straw, inducing behaviour similar to prepartum nest building.

18.
Brain Res Mol Brain Res ; 88(1-2): 26-36, 2001 Mar 31.
Article in English | MEDLINE | ID: mdl-11295229

ABSTRACT

Neurotrophins have been implicated in memory consolidation and recall as well as in other forms of neural plasticity. This study examined the effects of Brain-Derived Neurotrophic Factor (BDNF), Nerve Growth Factor (NGF) and Neurotrophin-3 (NT-3) on consolidation of memory for a one-trial passive avoidance task in day-old chicks. In this task chicks, having pecked once at a bitter tasting bead, avoid a similar but dry bead subsequently. Intracerebral administration of antisense ODNs to BDNF 6-12 h prior to training induced amnesia for the avoidance response by 3 h after training. Administration of a "control" scrambled sequence or saline had no effect on recall; chicks continued to avoid the bead. Treatment with BDNF-AS did not inhibit shorter-term recall; amnesia was not present 1 h after training, but prevented longer-term recall, as amnesia was still present 24 h after training. Treatment with BDNF-antisense reduced both BDNF mRNA and BDNF protein in the chick brain, but did not alter mRNA levels of glyceraldehyde-3-phosphate dehydrogenase. By contrast, no effect of antisense to NGF or NT-3 on behaviour was observed, even though administration reduced the mRNA for each. There were no significant effects of any antisense on other behavioural measures at the doses used. Thus we conclude that BDNF has a specific role in memory consolidation for the passive avoidance task.


Subject(s)
Avoidance Learning/physiology , Memory/physiology , Nerve Growth Factors/genetics , Age Factors , Animals , Brain Chemistry/physiology , Brain-Derived Neurotrophic Factor/analysis , Brain-Derived Neurotrophic Factor/genetics , Chickens , Enzyme-Linked Immunosorbent Assay , Feeding Behavior/physiology , In Situ Hybridization , Nerve Growth Factor/genetics , Neurotrophin 3/genetics , Oligonucleotides, Antisense/pharmacology , RNA, Messenger/analysis
19.
Neural Plast ; 8(4): 255-70, 2001.
Article in English | MEDLINE | ID: mdl-12018773

ABSTRACT

We have previously reported the presence of dehydroepiandosterone (DHEA) in the day-old-chick brain, and a role for it in enhanced memory formation. Here we confirm that intracerebral injections of DHEA 5 min before training on the weak passive avoidance task enhanced recall 24 hours after training. Recall per se on an appetitive visual categorization task was not altered by administration of DHEA 5 min before training. However administration of DHEA 5 min before limited or very limited training on a visual categorization task (20 or 10 pecks only) appeared to enhance consolidation of this task at test 24 h after training; reducing the latency and total time taken to complete the test (60 pecks), while not detrimentally altering accuracy. Moreover, DHEA is unlikely to induce this effect via possible anxiolytic effects because it did not alter behavior in the open field test. We also examined diffusion of DHEA throughout the brain at various stages following intracerebral injection.


Subject(s)
Avoidance Learning/drug effects , Chickens/physiology , Dehydroepiandrosterone/pharmacology , Memory/drug effects , Animals , Animals, Newborn , Avoidance Learning/physiology , Brain/physiology , Dehydroepiandrosterone/metabolism , Injections , Memory/physiology , Mental Recall/drug effects , Time Factors
20.
Eur J Neurosci ; 12(12): 4487-95, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11122359

ABSTRACT

The amyloid beta/A4 protein precursor (APP) has been shown to be implicated in age-associated plastic changes at synapses that might contribute to memory loss in Alzheimer's disease. As APP has previously been reported to have multiple functions during normal development, we have employed a one-trial passive avoidance task in day-old chicks to study its role in the process of memory formation. Administration of anti-APP antibodies, injected 30 min pretraining, prevented memory for a one-trial passive avoidance task in day-old chicks without effects on general behaviour or initial acquisition. Amnesia was apparent by 30 min post-training and lasted for at least 24 h. The same result was obtained by down-regulation of APP expression by APP-antisense, injected 8-12 h pretraining. However, injections of anti-APP antibodies or APP antisense at later post-training time did not cause amnesia for the task. Unlike antibodies and antisense, injection of the APP328-332 pentapeptide, in either orientation, 30 min pretraining, rescued the memory and prevented antisense-induced amnesia. The post-training time within which the antibody- and antisense-induced amnesia, and within which the APP peptides prevent amnesia, correspond to that during which memory formation is vulnerable to disruption of the putative signal transduction functions of APP. These results suggest that: (i) APP is required during an early phase of memory formation, and (ii) the memory enhancing effect of secretory APP is localized within a 5-mer sequence of growth-promoting domain.


Subject(s)
Amyloid beta-Protein Precursor/physiology , Antibodies, Monoclonal/pharmacology , Avoidance Learning/physiology , Brain/physiology , Memory/physiology , Amnesia , Amyloid beta-Protein Precursor/antagonists & inhibitors , Amyloid beta-Protein Precursor/genetics , Animals , Avoidance Learning/drug effects , Brain/cytology , Cell Membrane/physiology , Cell Membrane/ultrastructure , Chickens , Gene Expression Regulation , Glial Fibrillary Acidic Protein/analysis , Glial Fibrillary Acidic Protein/genetics , Memory/drug effects , Oligopeptides/pharmacology , RNA, Messenger/analysis , Synaptic Membranes/physiology , Synaptic Membranes/ultrastructure , Time Factors
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