scholarly journals Experimental Infection of North American Sheep with Ehrlichia ruminantium

Pathogens ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 451
Author(s):  
Arathy Nair ◽  
Paidashe Hove ◽  
Huitao Liu ◽  
Ying Wang ◽  
Ada G. Cino-Ozuna ◽  
...  
Keyword(s):  
Scientific Evidence ◽  
Clinical Signs ◽  
Western Hemisphere ◽  
Igg Antibody ◽  
Ehrlichia Ruminantium ◽  
Tick Vector ◽  
Ruminant Species ◽  
The Usa ◽  
Infection Study

Ehrlichia ruminantium, a tick-borne rickettsial, causes heartwater in ruminants resulting from vascular damage. Severity of heartwater varies greatly in ruminant species and breeds, age of animals and for diverse geographic E. ruminantium strains. E. ruminantium and a tick vector, Amblyomma variegatum, originating from Africa, are well established in certain Caribbean islands two centuries ago. Besides the possibility of introduction of heartwater through African exotic animal importation, presence of the pathogen, and the tick vector in the Caribbean pose a high risk to ruminants in the USA and other western hemisphere countries. Scientific evidence supporting the heartwater threat to nonendemic regions, however, is lacking. We describe the first infection study in sheep reared in the USA with seven E. ruminantium strains. All infected sheep exhibited clinical signs characteristic of subacute to subclinical disease, which included labored breathing, depression, coughing, and nasal discharges. Gross and microscopic lesions consistent with heartwater disease including edema and hemorrhage were observed in several organs. Pathogen-specific IgG antibody response was detected in animals infected with all seven strains, while molecular analysis confirmed the pathogen presence only when infected with in vitro cultures. This is the first infection study demonstrating severe heartwater in sheep reared in North America.

scholarly journals First Cases of Natural Infections with Borrelia hispanica in Two Dogs and a Cat from Europe

2020 ◽  
Vol 8 (8) ◽  
pp. 1251
Author(s):  
Gabriele Margos ◽  
Nikola Pantchev ◽  
Majda Globokar ◽  
Javier Lopez ◽  
Jaume Rodon ◽  
...  
Keyword(s):  
Molecular Analysis ◽  
Phylogenetic Analyses ◽  
Clinical Signs ◽  
Housekeeping Genes ◽  
Laboratory Findings ◽  
Borrelia Hermsii ◽  
Babesia Vogeli ◽  
Blood Smears ◽  
The Usa

Canine cases of relapsing fever (RF) borreliosis have been described in Israel and the USA, where two RF species, Borrelia turicatae and Borrelia hermsii, can cause similar clinical signs to the Borrelia persica in dogs and cats reported from Israel, including fever, lethargy, anorexia, thrombocytopenia, and spirochetemia. In this report, we describe the first clinical cases of two dogs and a cat from Spain (Cordoba, Valencia, and Seville) caused by the RF species Borrelia hispanica. Spirochetes were present in the blood smears of all three animals, and clinical signs included lethargy, pale mucosa, anorexia, cachexia, or mild abdominal respiration. Laboratory findings, like thrombocytopenia in both dogs, may have been caused by co-infecting pathogens (i.e., Babesia vogeli, confirmed in one dog). Anemia was noticed in one of the dogs and in the cat. Borrelia hispanica was confirmed as an infecting agent by molecular analysis of the 16S rRNA locus. Molecular analysis of housekeeping genes and phylogenetic analyses, as well as successful in vitro culture of the feline isolate confirmed the causative agent as B. hispanica.

scholarly journals Intra-nasal Inoculation of American Bison (Bison bison) with Ovine Herpesvirus-2 (OvHV-2) Reliably Reproduces Malignant Catarrhal Fever

2007 ◽  
Vol 44 (5) ◽  
pp. 655-662 ◽  
Author(s):  
D. O'Toole ◽  
N. S. Taus ◽  
D. L. Montgomery ◽  
J. L. Oaks ◽  
T. B. Crawford ◽  
...  
Keyword(s):  
Experimental Studies ◽  
Clinical Signs ◽  
Bison Bison ◽  
Malignant Catarrhal Fever ◽  
Blood Leukocytes ◽  
Ruminant Species ◽  
Nasal Secretions ◽  
Polymerase Chain ◽  
Route Of Exposure

Sheep-associated malignant catarrhal fever (MCF) due to infection with ovine herpesvirus 2 (OvHV-2) is common in commercial herds of American bison ( Bison bison). Inability to propagate OvHV-2 in vitro has been a constraint on experimental studies of the disease. We sought to establish whether nasal secretions from sheep that shed OvHV-2 might induce the disease in bison and to define a minimum challenge dose. Fourteen bison were nebulized with sheep nasal sections containing 103–107 OvHV-2 deoxyribonucleic acid (DNA) copies. Most challenged bison (11/14, 78.6%) developed clinical signs at 29–52 days postnebulization (DPN). The mean incubation time was 42.18 (±7.33 SD) DPN. Using real-time polymerase chain reaction, we detected OvHV-2 DNA in peripheral blood leukocytes at 21–31 DPN. All bison that developed MCF had antibodies against the MCF group viruses. Gross and histologic lesions were typical of the acute disease. There was no morphologic evidence of a dose-related difference in the severity or distribution of lesions. This is the first successful reproduction of MCF in bison using a nasal route of exposure. Experimentally challenged bison are more susceptible to MCF, compared with experimentally challenged domestic cattle in a previous experiment. Bison are a pertinent ruminant species in which the pathogenesis of the disease can be investigated.

scholarly journals Immunization with Recombinant Sao Protein Confers Protection against Streptococcus suis Infection

2007 ◽  
Vol 14 (8) ◽  
pp. 937-943 ◽  
Author(s):  
Yuanyi Li ◽  
Marcelo Gottschalk ◽  
Miriam Esgleas ◽  
Sonia Lacouture ◽  
J. Daniel Dubreuil ◽  
...  
Keyword(s):  
Clinical Signs ◽  
Surface Protein ◽  
Streptococcus Suis ◽  
Cross Protection ◽  
Antibody Responses ◽  
Control Group ◽  
Igg Antibody ◽  
Tissue Samples ◽  
Vitro Assay

ABSTRACT Sao is a Streptococcus suis surface protein recently identified as a potential vaccine candidate. In this study, recombinant Sao in combination with Quil A provided cross-protection against S. suis serotype 2 disease in mouse and pig vaccination protocols. Subcutaneous immunization of mice elicited strong immunoglobulin G (IgG) antibody responses. All four IgG subclasses were induced, with the IgG2a titer being the highest, followed by those of IgG1, IgG2b, and IgG3. Challenge of the mice with S. suis strain 31533 resulted in a mortality rate of 80% for the control group, which received Quil A only. In contrast, all of the mice immunized with Sao survived. In a pig vaccination protocol, intramuscular immunization with Sao also elicited significant humoral antibody responses, and both the IgG1 and IgG2 subclasses were induced, with a predominance of IgG2 production. In vitro assay showed that Sao-induced antibodies significantly promoted the ability of porcine neutrophils in opsonophagocytic killing of S. suis. An aerosol challenge of the pigs with S. suis strain 166 resulted in clinical signs characteristic of S. suis infection in diseased pigs. The vaccine group showed significantly better survival, lower clinical scores, and less S. suis recovery from postmortem tissue samples than did the control group. Furthermore, this study also revealed that although challenge S. suis strains express Sao size variants, recombinant Sao conferred cross-protection. These data demonstrate that recombinant Sao formulated with Quil A triggers strong opsonizing antibody responses which confer efficient immunity against challenge infection with heterologous S. suis type 2.

scholarly journals “A debriefer must be neutral” and other debriefing myths: a systemic inquiry-based qualitative study of taken-for-granted beliefs about clinical post-event debriefing

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Julia Carolin Seelandt ◽  
Katie Walker ◽  
Michaela Kolbe
Keyword(s):  
Interpersonal Relationships ◽  
Western Europe ◽  
Ad Hoc ◽  
Scientific Evidence ◽  
Clinical Event ◽  
Clinical Settings ◽  
Healthcare Organizations ◽  
The Usa ◽  
Open Coding ◽  
Healthcare Administrators

Abstract Background The goal of this study was to identify taken-for-granted beliefs and assumptions about use, costs, and facilitation of post-event debriefing. These myths prevent the ubiquitous uptake of post-event debriefing in clinical units, and therefore the identification of process, teamwork, and latent safety threats that lead to medical error. By naming these false barriers and assumptions, the authors believe that clinical event debriefing can be implemented more broadly. Methods We interviewed an international sample of 37 clinicians, educators, scholars, researchers, and healthcare administrators from hospitals, universities, and healthcare organizations in Western Europe and the USA, who had a broad range of debriefing experience. We adopted a systemic-constructivist approach that aimed at exploring in-depth assumptions about debriefing beyond obvious constraints such as time and logistics and focused on interpersonal relationships within organizations. Using circular questions, we intended to uncover new and tacit knowledge about barriers and facilitators of regular clinical debriefings. All interviews were transcribed and analyzed following a comprehensive process of inductive open coding. Results In total, 1508.62 min of interviews (25 h, 9 min, and 2 s) were analyzed, and 1591 answers were categorized. Many implicit debriefing theories reflected current scientific evidence, particularly with respect to debriefing value and topics, the complexity and difficulty of facilitation, the importance of structuring the debriefing and engaging in reflective practice to advance debriefing skills. We also identified four debriefing myths which may prevent post-event debriefing from being implemented in clinical units. Conclusion The debriefing myths include (1) debriefing only when disaster strikes, (2) debriefing is a luxury, (3) senior clinicians should determine debriefing content, and (4) debriefers must be neutral and nonjudgmental. These myths offer valuable insights into why current debriefing practices are ad hoc and not embedded into daily unit practices. They may help ignite a renewed momentum into the implementation of post-event debriefing in clinical settings.

scholarly journals Feasibility of using a biofeedback device in mindfulness training - a pilot randomized controlled trial

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Brenna Lin ◽  
Christopher Prickett ◽  
Steven Woltering
Keyword(s):  
College Students ◽  
Mindfulness Meditation ◽  
Controlled Trial ◽  
Scientific Evidence ◽  
Well Being ◽  
Open Science ◽  
Control Group ◽  
Test Procedures ◽  
The Usa ◽  
Biofeedback Device

Abstract Background Stress can negatively impact an individual’s health and well-being and high levels of stress are noted to exist among college students today. While traditional treatment methods are plagued with stigma and transfer problems, newly developed wearable biofeedback devices may offer unexplored possibilities. Although these products are becoming commonplace and inexpensive, scientific evidence of the effectiveness of these products is scarce and their feasibility within research contexts are relatively unexplored. Conversely, companies are not required, and possibly reluctant, to release information on the efficacy of these products against their claims. Thus, in the present pilot, we assess the feasibility of using a real-time respiratory-based biofeedback device in preparation for a larger study. Our main aims were to assess device-adherence and collaboration with the company that develops and sells the device. Method Data were collected from 39 college students who self-identified as experiencing chronic stress at a Southwestern university in the USA. Students were randomized into either a mindfulness-only control group without a biofeedback device (n = 21), or an experimental group with biofeedback device (n = 18). Both groups received mindfulness meditation training. Pre-test and post-test procedures were conducted 2 weeks apart. Further, both participant compliance and company compliance were assessed and collaboration with the company was evaluated. Results Participant device-adherence as well as the company’s collaboration necessary for a full-scale study was determined to be low. This may also have affected our results which showed a strong main effect for time for all outcome variables, suggesting all groups showed improvement in their levels of stress after the intervention period. No group by time effects were identified, however, indicating no added benefit of the biofeedback device. Conclusions Our findings suggest feasibility of future studies requires full collaboration and detailed and agreed upon data sharing procedures with the biofeedback company. The particular device under investigation added no value to the intervention outcomes and it was not feasible to continue a larger-scale study. Further, as the technology sector is innovating faster than it can validate products, we urge for open science collaborations between public and private sectors to properly develop evidence-based regulations that can withstand technological innovation while maintaining product quality, safety, and effectiveness. Trial registration NCT02837016. Registered 19 July 2016.

scholarly journals Low Maternal Immunoglobulin G Avidity and Single Parity as Adverse Implications of Human Cytomegalovirus Vertical Transmission in Pregnant Women with Immunoglobulin M Positivity

Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 866
Author(s):  
Masatoki Kaneko ◽  
Junsuke Muraoka ◽  
Kazumi Kusumoto ◽  
Toshio Minematsu
Keyword(s):  
Risk Factors ◽  
Pregnant Women ◽  
Vertical Transmission ◽  
Human Cytomegalovirus ◽  
Multiple Logistic Regression Analysis ◽  
Clinical Signs ◽  
Immunoglobulin M ◽  
Igg Antibody ◽  
Neurological Sequelae ◽  
Previous Pregnancy

Human cytomegalovirus (CMV) is the leading cause of neurological sequelae in infants. Understanding the risk factors of primary CMV infection is crucial in establishing preventive strategies. Thus, we conducted a retrospective cohort study to identify risk factors of vertical transmission among pregnant women with immunoglobulin (Ig) M positivity. The study included 456 pregnant women with IgM positivity. Information on age, parity, occupation, clinical signs, IgM levels, and IgG avidity index (AI) was collected. The women were divided into infected and non-infected groups. The two groups showed significant differences in IgM level, IgG AI, number of women with low IgG AI, clinical signs, and number of pregnant women with single parity. In the multiple logistic regression analysis, pregnant women with single parity and low IgG AI were independent predictors. Among 40 women who tested negative for IgG antibody in their previous pregnancy, 20 showed low IgG AI in their current pregnancy. Among the 20 women, 4 had vertical transmission. These results provide better understanding of the risk factors of vertical transmission in pregnant women with IgM positivity.

scholarly journals Revisiting Ehrlichia ruminantium Replication Cycle Using Proteomics: The Host and the Bacterium Perspectives

2021 ◽  
Vol 9 (6) ◽  
pp. 1144
Author(s):  
Isabel Marcelino ◽  
Philippe Holzmuller ◽  
Ana Coelho ◽  
Gabriel Mazzucchelli ◽  
Bernard Fernandez ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Host Cell ◽  
Cell Metabolism ◽  
Replication Cycle ◽  
Host Cells ◽  
Ehrlichia Ruminantium ◽  
Host Interaction ◽  
Infected Cells ◽  
Related Proteins

The Rickettsiales Ehrlichia ruminantium, the causal agent of the fatal tick-borne disease Heartwater, induces severe damage to the vascular endothelium in ruminants. Nevertheless, E. ruminantium-induced pathobiology remains largely unknown. Our work paves the way for understanding this phenomenon by using quantitative proteomic analyses (2D-DIGE-MS/MS, 1DE-nanoLC-MS/MS and biotin-nanoUPLC-MS/MS) of host bovine aorta endothelial cells (BAE) during the in vitro bacterium intracellular replication cycle. We detect 265 bacterial proteins (including virulence factors), at all time-points of the E. ruminantium replication cycle, highlighting a dynamic bacterium–host interaction. We show that E. ruminantium infection modulates the expression of 433 host proteins: 98 being over-expressed, 161 under-expressed, 140 detected only in infected BAE cells and 34 exclusively detected in non-infected cells. Cystoscape integrated data analysis shows that these proteins lead to major changes in host cell immune responses, host cell metabolism and vesicle trafficking, with a clear involvement of inflammation-related proteins in this process. Our findings led to the first model of E. ruminantium infection in host cells in vitro, and we highlight potential biomarkers of E. ruminantium infection in endothelial cells (such as ROCK1, TMEM16K, Albumin and PTPN1), which may be important to further combat Heartwater, namely by developing non-antibiotic-based strategies.

scholarly journals Direct Binding of Human NK Cell Natural Cytotoxicity Receptor NKp44 to the Surfaces of Mycobacteria and Other Bacteria

2008 ◽  
Vol 76 (4) ◽  
pp. 1719-1727 ◽  
Author(s):  
Semih Esin ◽  
Giovanna Batoni ◽  
Claudio Counoupas ◽  
Annarita Stringaro ◽  
Franca Lisa Brancatisano ◽  
...  
Keyword(s):  
Nk Cells ◽  
Nk Cell ◽  
Cell Subset ◽  
Surface Expression ◽  
Binding Assays ◽  
Igg Antibody ◽  
Direct Stimulation ◽  
Activating Receptors ◽  
Accessory Cells

ABSTRACT Our previous studies demonstrated that Mycobacterium bovis bacillus Calmette-Guérin (BCG) can directly interact with human NK cells and induce the proliferation, gamma interferon production, and cytotoxic activity of such cells without the need for accessory cells. Thus, the aim of the present study was to identify the putative receptor(s) responsible for the recognition of BCG by human NK cells and potentially involved in the activation of NK cells. To this end, we first investigated the surface expression of three NK cell-activating receptors belonging to the natural cytoxicity receptor (NCR) family on highly purified human NK cells upon in vitro direct stimulation with BCG. An induction of the surface expression of NKp44, but not of NKp30 or NKp46, was observed after 3 and 4 days of in vitro stimulation with live BCG. The NKp44 induction involved mainly a particular NK cell subset expressing the CD56 marker at high density, CD56bright. In order to establish whether NKp44 could directly bind to BCG, whole BCG cells were stained with soluble forms of the three NCRs chimeric for the human immunoglobulin G (IgG) Fc fragment (NKp30-Fc, NKp44-Fc, NKp46-Fc), followed by incubation with a phycoerythrin (PE)-conjugated goat anti-human IgG antibody. Analysis by flow cytometry of the complexes revealed a higher PE fluorescence intensity for BCG incubated with NKp44-Fc than for BCG incubated with NKp30-Fc, NKp46-Fc, or negative controls. The binding of NKp44-Fc to the BCG surface was confirmed with immunogold labeling using transmission electron microscopy, suggesting the presence of a putative ligand(s) for human NKp44 on the BCG cell wall. Similar binding assays performed on a number of gram-positive and gram-negative bacteria revealed a pattern of NKp44-Fc binding restricted to members of the genus Mycobacterium, to the mycobacterium-related species Nocardia farcinica, and to Pseudomonas aeruginosa. Altogether, the results obtained indicate, for the first time, that at least one member of the NCR family (NKp44) may be involved in the direct recognition of bacterial pathogens by human NK cells.

scholarly journals A “Smart” Biosensor-Enabled Intravascular Catheter and Platform for Dynamic Delivery of Propofol to “Close the Loop” for Total Intravenous Anesthesia

2021 ◽  
Vol 186 (Supplement_1) ◽  
pp. 370-377
Author(s):  
Edward Chaum ◽  
Ernő Lindner
Keyword(s):  
Real Time ◽  
Drug Distribution ◽  
Population Based ◽  
Pharmacokinetic Data ◽  
Drug Infusion ◽  
Blood Concentrations ◽  
The Usa ◽  
The Difference ◽  
Automated Delivery

ABSTRACT Background Target-controlled infusion anesthesia is used worldwide to provide user-defined, stable, blood concentrations of propofol for sedation and anesthesia. The drug infusion is controlled by a microprocessor that uses population-based pharmacokinetic data and patient biometrics to estimate the required infusion rate to replace losses from the blood compartment due to drug distribution and metabolism. The objective of the research was to develop and validate a method to detect and quantify propofol levels in the blood, to improve the safety of propofol use, and to demonstrate a pathway for regulatory approval for its use in the USA. Methods We conceptualized and prototyped a novel “smart” biosensor-enabled intravenous catheter capable of quantifying propofol at physiologic levels in the blood, in real time. The clinical embodiment of the platform is comprised of a “smart” biosensor-enabled catheter prototype, a signal generation/detection readout display, and a driving electronics software. The biosensor was validated in vitro using a variety of electrochemical methods in both static and flow systems with biofluids, including blood. Results We present data demonstrating the experimental detection and quantification of propofol at sub-micromolar concentrations using this biosensor and method. Detection of the drug is rapid and stable with negligible biofouling due to the sensor coating. It shows a linear correlation with mass spectroscopy methods. An intuitive graphical user interface was developed to: (1) detect and quantify the propofol sensor signal, (2) determine the difference between targeted and actual propofol concentration, (3) communicate the variance in real time, and (4) use the output of the controller to drive drug delivery from an in-line syringe pump. The automated delivery and maintenance of propofol levels was demonstrated in a modeled benchtop “patient” applying the known pharmacokinetics of the drug using published algorithms. Conclusions We present a proof-of-concept and in vitro validation of accurate electrochemical quantification of propofol directly from the blood and the design and prototyping of a “smart,” indwelling, biosensor-enabled catheter and demonstrate feedback hardware and software architecture permitting accurate measurement of propofol in blood in real time. The controller platform is shown to permit autonomous, “closed-loop” delivery of the drug and maintenance of user-defined propofol levels in a dynamic flow model.

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