Ovine enzootic abortion (OEA) caused by the obligate intracellular bacterial pathogen Chlamydia abortus (C. abortus), is an endemic disease in most sheep-rearing countries worldwide. Following infection, C. abortus establishes a complex host–pathogen interaction with a latent phase in non-pregnant sheep followed by an active disease phase in the placenta during pregnancy leading to OEA. Improved knowledge of the host–pathogen interactions at these different phases of disease will accelerate the development of new diagnostic tests and vaccines to control OEA. Current evidence indicates that cellular immunity is essential for controlling C. abortus infection. We have previously described a model of mucosal (intranasal) infection of non-pregnant sheep with C. abortus that replicates the latent and active phases of OEA. We have investigated antigen-specific recall responses of peripheral blood mononuclear cells (PBMC) in sheep infected with C. abortus via the intranasal route to determine how these change during the latent and active phases of disease. By analysing cytokines associated with the major CD4+ve Thelper (Th) cell subsets (Interferon-gamma (IFN-γ)/Th1; Interleukin (IL)-4/Th2; IL-17A/Th17; IL-10/Tregulatory), we show that there is selective activation of PBMC producing IFN-γ and/or IL-10 during the latent phase following infection. These cytokines are also elevated during the active disease phase and while they are produced by sheep that are protected from OEA, they are also produced by sheep that abort, highlighting the difficulties in finding specific cellular immunological correlates of protection for complex intracellular pathogens.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Identification of and the development of lesions in placental tissues of experimentally infected sheep S.W. Maley, M. Livingstone, S.M. Rodger, D. Longbottom, D. Buxton

Child and adolescent psychiatrists have an important role in educating and helping the emerging field of palliative care. Their knowledge of development, psychotherapy, family structures, psychopharmacology, and medical culture is key to allowing palliative care to reach its goal of holistic treatment of patients. Because child and adolescent psychiatrists have medical training, they can incorporate the complex biopsychosocial picture of this severely ill population into their diagnostic evaluations. Furthermore, their medical understanding of prognostication can help provide more complete psychosocial interventions and treatment recommendations. Without this expertise, palliative care providers can misinterpret behaviors and lose opportunities to treat important elements of suffering.

Infection with Neospora caninum stimulates host cell-mediated immune responses, which may be responsible for placental damage leading to bovine abortion. The aim of this study was to compare immune responses in the bovine placenta, following experimental infection in different stages of pregnancy. Placentomes were examined by immunohistochemistry and inflammation in early gestation was generally moderate to severe, particularly in the placentas carrying non-viable foetuses, whereas it was milder in later stages, mainly characterised by the presence of CD3 + , CD4 + and γδ T-cells. This distinctive cellular immune response may explain the milder clinical outcome observed when animals are infected in later gestation.

Neospora caninum is recognized as a major cause of reproductive losses worldwide but its pathogenesis is not completely understood. Immune mediated placental pathology has been reported as being responsible for compromising pregnancy probably due to the adverse effects of exacerbated Th1 type response at the maternal–foetal interface. Different clinical outcomes are known to occur following experimental infections of cattle at different stages of gestation, with foetal death being the most common finding during early gestation, and the birth of live congenitally infected calves following infection later in gestation. The aim of the current study was to characterize the cytokine expression in the placenta of cattle experimentally challenged with tachyzoites of the Nc-1 strain during early, mid and late gestation. Moderate to severe infiltration of IL-12, IFN-γ and TNF-α expressing cells was observed in the placentas collected at early gestation and this infiltration was more pronounced in the samples collected from challenged dams carrying non-viable foetuses, compared with the mothers carrying viable foetuses. In contrast, the infiltration of Th1 cytokine expressing-cells was mild following N. caninum infection in mid gestation and scarce during infection in late gestation. Scarce expression of IL-4 was observed in the placentas from N. caninum-challenged and negative control animals throughout gestation. The milder Th1 immune response observed during later stages of gestation following Nc-1 infection could partially explain the less severe clinical outcome when compared to early pregnancy.

Latency is a key feature of the animal pathogen Chlamydia abortus, where infection remains inapparent in the non-pregnant animal and only becomes evident during a subsequent pregnancy. Often the first sign that an animal is infected is abortion occurring late in gestation. Despite this, little is understood of the underlying mechanisms that control latency or the recrudescence of infection that occurs during subsequent pregnancy. The aim of this study was to develop an experimental model of latency by mimicking the natural route of infection through the intranasal inoculation of non-pregnant sheep with C. abortus.Three groups of sheep (groups 1, 2 and 3) were experimentally infected with different doses of C. abortus (5×10(3), 5×10(5) and 5×10(7) inclusion forming units (IFU), respectively) prior to mating and monitored over 2 breeding cycles for clinical, microbiological, pathological, immunological and serological outcomes. Two further groups received either negative control inoculum (group 4a,b) or were inoculated subcutaneously on day 70 of gestation with 2×10(6) IFU C. abortus (group 5). Animals in groups 1, 2 and 5 experienced an abortion rate of 50-67%, while only one animal aborted in group 3 and none in group 4a,b. Pathological, microbiological, immunological and serological analyses support the view that the maternal protective immune response is influenced by initial exposure to the bacterium.The results show that intranasal administration of non-pregnant sheep with a low/medium dose of C. abortus results in a latent infection that leads in a subsequent pregnancy to infection of the placenta and abortion. In contrast a high dose stimulates protective immunity, resulting in a much lower abortion rate. This model will be useful in understanding the mechanisms of infection underlying latency and onset of disease, as well as in the development of novel therapeutics and vaccines for controlling infection.

In 2009, there were 6.4 million hospital stays for patients aged younger than 17 years, accounting for 17% of all US hospital inpatient care. The average length of stay was 3.8 days.1 An estimated 150,000 to 200,000 of these children require pediatric intensive care units (PICU) due to the severity of their illness. Research has shown that the PICU experience is not only stressful for children but also their families. Mothers have been noted to perceive their family functioning as dysfunctional even up to 6 months after discharge from a hospital.2 In a study of parents whose children recently had received a cancer diagnosis, 40% of fathers and more than 50% of mothers met criteria for acute stress disorder.3 In addition, fathers and mothers have been found to have poor concordance in assessing their seriously ill child’s psychosocial health, emotional function, communication, and cognitive fatigue. This difference can lead to family discord.4 A combination of these factors may account for frustration and anger toward each other and hospital staff. It has been noted that 68% of nurses have been verbally abused by a patient’s family member.5 Even when relationships are challenging, pediatric health care providers must work with families to ensure high-quality care to their children. Another contributing factor to tenWorking with Families Perceived as Difficult

Journal of Palliative MedicineVol. 16, No. 11 Personal ReflectionNoncompliance: The Pot Calling the Kettle BlackDavid BuxtonDavid BuxtonPublished Online:11 Nov 2013https://doi.org/10.1089/jpm.2013.0131AboutSectionsView articleView Full TextPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookXLinked InRedditEmail View article"Noncompliance: The Pot Calling the Kettle Black." , 16(11), p. 1485FiguresReferencesRelatedDetailsCited byPatient assessment of primary care physician communication: segmentation approachInternational Journal of Health Care Quality Assurance, Vol. 28, No. 4 Volume 16Issue 11Nov 2013 InformationCopyright 2013, Mary Ann Liebert, Inc.To cite this article:David Buxton.Noncompliance: The Pot Calling the Kettle Black.Journal of Palliative Medicine.Nov 2013.1485-1485.http://doi.org/10.1089/jpm.2013.0131Published in Volume: 16 Issue 11: November 11, 2013Online Ahead of Print:October 12, 2013 PDF download

CME Educational Objectives 1. Distinguish what types of bullying are most common at different ages. 2. Describe six questions to screen for bullying and its effects. 3. Identify three interventions for students and parents to address bullying, victimization, bystanding, and system rules that allow bullying. Bullying affects most children in some way, as victims, bystanders, or bullies, during childhood. Children exposed to bullying may present with physical as well as psychological symptoms, and experience negative effects lasting into adulthood. This article provides information regarding bullying screening and interventions with pediatric and adolescent patients. Taking into account a child’s developmental stage, age-appropriate tactics are provided to address bullying, victimization, bystanding, and system “rules” that tolerate or foster bullying.

Six ovine fetal brains were harvested 33 to 35 days postchallenge from 5 ewes, each of which was given 3000 Toxoplasma gondii oocysts on day 90 of pregnancy. Histopathologic examination of transverse sections taken at 13 levels in the fetal brains revealed the presence of toxoplasmosis-related lesions in all 6 brains. However, lesions were not randomly distributed (P = .007); they were most numerous at the level of the optic tract, the rostral margin of the pons, and 4 mm caudal to the ansate sulcus and were absent in all sections at the level of the caudal cerebellum. Lesion distribution may be due to hemodynamic factors, differences in the expression of endothelial surface receptor molecules at the level of the blood-brain barrier, or the presence of localized permissive/inhibitory factors within the brain. The results have implications for the selection of areas of brain from aborted ovine fetuses to be examined histopathologically for laboratory diagnosis.

Toxoplasma gondii, an intracellular protozoan parasite, is one of the major causes of infectious abortion in sheep. To further understand the pathogenesis of toxoplasmosis, serum, amniotic and allantoic fluids and foetal stomach contents were collected from experimentally infected pregnant ewes to determine pathogen numbers and other markers of infection. Fifteen pregnant ewes (90 days of gestation) were each orally inoculated with 3000 sporulated oocysts of T. gondii. Serum samples were collected weekly following challenge. Amniotic and allantoic fluids and foetal stomach contents were collected at 21, 25, 28, 33 and 35 days post-infection. Characteristic placental lesions were detected in 1 of 4 challenged ewes at day 25, 3 of 4 challenged ewes at day 28 and in all challenged ewes at days 33 and 35 post-infection. T. gondii was detected only sporadically in amniotic and allantoic fluids before 35 days of infection, by real-time PCR, and only in ewes with placental lesions. At 35 days post-infection, high numbers of parasite were detected in both amniotic and allantoic fluids. An increase in the number of fluids from challenged animals with IgM and IgG was detected over time, except for IgG in allantoic fluid, which was detected in all samples from day 21 post-infection. IgG in amniotic and allantoic fluids was shown to be specific for T. gondii, and reacted with antigens with an apparent molecular mass of approximately 22 kDa and 30 kDa. Results suggest a maternal source of immunoglobulin in the allantoic fluid and a foetal source of immunoglobulin in the amniotic fluid early in infection but that both sources may contribute immunoglobulin to both fluids at a later stage.

Toxoplasma gondii and Chlamydophila abortus are the 2 most common infectious causes of ovine abortion worldwide. These obligate intracellular pathogens are associated with severe placentitis leading to abortion or stillbirth in pregnant ewes, and resulting in significant economic losses. The objectives of the current study were the development, validation, and application of a duplex real-time polymerase chain reaction (PCR) assay capable of quantifying the burden of infection by T. gondii and C. abortus in material submitted for diagnostic purposes. The validation was carried out using samples from ewes experimentally infected with these organisms. Based on the numbers of genome copies detected, an arbitrary cutoff level was established to correlate with significant pathological changes sufficient to give rise to abortion. When the PCR assay was applied to samples from 66 Irish farms with naturally occurring outbreaks of ovine abortion, toxoplasmosis and enzootic abortion of ewes (EAE) accounted for 14% and 20% of the farms, respectively, while on 6% of the farms, there was evidence of dual infection. When standard diagnostic techniques including histopathological examination, serological analysis, chlamydial antigen detection, and bacteriological culture, were used on samples from the same farms, toxoplasmosis was diagnosed in 17% of farms, and EAE in 12%; dual infection was diagnosed on 3% of the farms. In general, good agreement was found between the PCR and the standard methods. The duplex real-time PCR assay developed in this study has proved to be a very sensitive and rapid tool that might provide a valuable addition to the methods currently available for routine diagnosis of ovine abortions.

The immune responses of pregnant cattle and their foetuses were examined following inoculation on day 70 of gestation either intravenously (iv) (group 1) or subcutaneously (sc) (group 2) with live NC1 strain tachyzoites or with Vero cells (control) (group 3). Peripheral blood mononuclear cell (PBMC) responses to Neospora antigen and foetal viability were assessed throughout the experiment. Two animals from each group were sacrificed at 14, 28, 42 and 56 days post inoculation (pi). At post mortem, maternal lymph nodes, spleen and PBMC and when possible foetal spleen, thymus and PBMC samples were collected for analysis. Inoculation with NC1 (iv and sc) lead to foetal deaths in all group 1 dams (6/6) and in 3/6 group 2 dams from day 28pi; statistically significant (p ≤ 0.05) increases in cell-mediated immune (CMI) responses including antigen-specific cell proliferation and IFN-γ production as well as increased levels of IL-4, IL-10 and IL-12 were observed in challenged dams compared to the group 3 animals. Lymph node samples from the group 2 animals carrying live foetuses showed greater levels of cellular proliferation as well as significantly (p ≤ 0.05) higher levels of IFN-γ compared to the dams in group 2 carrying dead foetuses. Foetal spleen, thymus and PBMC samples demonstrated cellular proliferation as well as IFN-γ, IL-4, IL-10 and IL-12 production following mitogenic stimulation with Con A from day 14pi (day 84 gestation) onwards. This study shows that the generation of robust peripheral and local maternal CMI responses (lymphoproliferation, IFN-γ) may inhibit the vertical transmission of the parasite.

In order to investigate the pathogenesis of neosporosis following a primary infection in late pregnancy, cattle were subcutaneously challenged with 5 × 108Neospora caninum (NC1 isolate) tachyzoites at day 210 of gestation and serial necropsies were then carried out at 14, 28, 42 and 56 days post-infection (dpi). No abortions occurred and all the foetuses were viable at the time of euthanasia. There was a high rate of vertical transmission, as parasites were detected by immunohistochemical labelling and PCR in all the foetuses from 28 dpi. Focal necrotic lesions were observed in the placentomes of the placenta from 28 dpi and showed resolution during later time points, denoted by infiltration of inflammatory cells at 42 dpi and fibrosis at 56 dpi. Foetuses at 28 and 42 dpi showed scarce and isolated lesions which are unlikely to represent a threat to foetal viability. No lesions were observed in the foetuses at 14 or 56 dpi suggesting control of the infection and resolution of the lesions by maternal and foetal immune responses. Once infection was established, it could not be cleared from the host and vertical transmission of the parasite occurred in all infected hosts. Parasite was detected in the placenta at 28 dpi, while in previous experimental infections of cattle at day 70 and 140 of gestation using the same challenge model, it was already present at day 14 post infection. This suggests that a change in the maternal immune response plays a crucial role in limiting the initial infection during the last term of pregnancy.

The host–pathogen interaction is as a key feature during the formation of tissue cysts of Toxoplasma gondii within intermediate hosts. In this study, we investigated whether oral infection of lambs with T. gondii oocysts may be used as an experimental model in sheep to study this interaction, with the main objective being to detect the presence and distribution of lesions and parasite within different organs at different time points after oral infection. Lambs were infected with 5×103 and 5×105 sporulated T. gondii oocysts and culled at 2, 3, 5 and 6 weeks post-infection (WPI). During the infection, rectal temperature of the animals and serological antibodies against T. gondii were monitored. The presence of inflammatory lesions and parasite were evaluated through histological and immunohistochemical methods at different organs (brain, liver, lung, heart and lymph nodes). The lambs showed no clinical signs other than fever, and lesions appeared mainly in the brain, characterized by glial foci and perivascular cuffs, and in the heart, denoted by foci of interstitial myositis. Tissue cysts and tachyzoite-like structures were observed at all time points studied in the brain, where together with the glial foci they appeared mainly in the cerebral cortex of the forebrain and in the midbrain, but also in the heart, lung and lymph nodes. This study shows that oral infection with sporulated oocysts in lambs may provide a model for investigating the host–parasite interaction in situ during the development of tissue cysts.

Brain computed tomography perfusion imaging in acute stroke may help guide therapy. However, the perfusion thresholds defining potentially salvageable (penumbra) and irreversibly injured (infarct core) tissue require further validation. The aim of this study was to validate infarct core and penumbra perfusion thresholds in a rodent stroke model by developing and optimising perfusion computed tomography imaging, performing serial scanning and correlating scans with final histology. Stroke was induced in male Wistar rats ( n = 17) using the middle cerebral artery thread-occlusion method. Perfusion computed tomography scans were obtained immediately pre- and postocclusion, and every 30 min for 2·5 h. Histological changes of infarction were assessed after 24 h. High-quality maps of cerebral blood flow and cerebral blood volume were generated at multiple coronal planes after optimisation of contrast injection and scanning parameters. The prestroke absolute cerebral blood flow and cerebral blood volume values (mean ± SD) were 158·2 ± 49·94 ml/min per 100 g and 5·6 ± 1·13 ml per 100 g, respectively. Cerebral blood flow was significantly lower in the infarct region of interest than the contralateral hemisphere region of interest at all time points, except the 0·5 h postocclusion time point. However, cerebral blood volume was only significantly lower in the infarct region of interest than the contralateral hemisphere region of interest at the 1 h and the 1·5 h time points (postocclusion). This study has demonstrated for the first time the feasibility of performing perfusion computed tomography in the most commonly used animal model of stroke. The model will allow definitive studies to determine optimal thresholds and the reliability of perfusion computed tomography measures for infarct core and penumbra.

Journal of Palliative MedicineVol. 14, No. 6 Personal ReflectionThe Intern Experience: Facing DeathDavid BuxtonDavid BuxtonSearch for more papers by this authorPublished Online:8 Jun 2011https://doi.org/10.1089/jpm.2010.0512AboutSectionsView articleView Full TextPDF/EPUB ToolsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View article"The Intern Experience: Facing Death." , 14(6), pp. 784–785FiguresReferencesRelatedDetailsCited ByIs a good death possible in Australian critical and acute settings?: physician experiences with end-of-life care18 August 2014 | BMC Palliative Care, Vol. 13, No. 1 Volume 14Issue 6Jun 2011 InformationCopyright 2011, Mary Ann Liebert, Inc.To cite this article:David Buxton.The Intern Experience: Facing Death.Journal of Palliative Medicine.Jun 2011.784-785.http://doi.org/10.1089/jpm.2010.0512Published in Volume: 14 Issue 6: June 8, 2011PDF download

A real-time PCR (rt-PCR) targeting the 529-bp repeat element (RE) of Toxoplasma gondii was used to detect and quantify the parasite burden in maternal and foetal tissues in 18 seronegative ewes infected with 3000 toxoplasma oocysts on day 90 of pregnancy. The infected ewes were sacrificed in groups of 4-6 at 21, 25, 33 and 35 days post-challenge. Ten sham inoculated pregnant ewes were used as controls. T. gondii was not detected in the control ewes or their foeti. The parasite was only detected in the maternal tissues in a few of the challenged ewes on a small number of occasions where it was identified in spleen and uterine lymph nodes. T. gondii was detected in the foetal spleen and liver at the early sacrifice times but only sporadically thereafter. In the case of amniotic, allantoic and foetal aqueous humor samples T. gondii was only detected on a small number of occasions. However, it was found in the majority of the foetal lung and placentome samples throughout the study period, while placentomes and foetal brains contained high levels of the parasite during the later stages. Histopathological examination of placentome and brain tissue from the foeti in the present study revealed a strong correlation between histopathological lesions and quantities of the parasite DNA detected. These results indicate that the cotyledonary component of the foetal membranes is the sample of choice for the diagnosis of T. gondii by rt-PCR, followed by foetal lung and brain.

LEAD is one of the most commonly encountered poisons in farm animals; young cattle are particularly at risk due to their inquisitive nature ([Radostits and others 2007][1]). In the UK, a recent review of lead poisoning incidents indicated that paint was identified as the source in 46 per cent of

Objective: Differentiation of potentially salvageable ischaemic penumbra and irreversibly injured infarct core using computed tomography perfusion (CTP) imaging of brain post-stroke is increasingly being applied in acute stroke imaging to guide thrombolysis decisions. Validation of thresholds used to define penumbra and core is urgently required, as are serial scanning studies to determine whether thresholds change with time (analogous to DWI reversal). The aim of these initial studies was to perform serial CTP studies in an animal model, and correlate CTP maps with 24 hour histology.