scholarly journals Histopathology ofBordetella pertussisin the Baboon Model

2018 ◽  
Vol 86 (11) ◽  
Author(s):  
Lindsey I. Zimmerman ◽  
James F. Papin ◽  
Jason Warfel ◽  
Roman F. Wolf ◽  
Stanley D. Kosanke ◽  
...  
Keyword(s):  
Severe Disease ◽  
Clinical Signs ◽  
Human Infant ◽  
Mucus Production ◽  
Content Type ◽  
Age Related ◽  
Baboon Model ◽  
Relevant Animal Model ◽  
Significant Pathology ◽  
Conducting Airways

ABSTRACTPertussis is a severe respiratory disease caused byBordetella pertussis. The classic symptoms of pertussis include paroxysmal coughing with an inspiratory whoop, posttussive vomiting, cyanosis, and persistent coryzal symptoms. Infants under 2 months of age experience more severe disease, with most deaths occurring in this age group. Most of what is known about the pathology of pertussis in humans is from the evaluation of fatal human infant cases. The baboon model of pertussis provides the opportunity to evaluate the histopathology of severe but nonfatal pertussis. The baboon model recapitulates the characteristic clinical signs of pertussis observed in humans, including leukocytosis, paroxysmal coughing, mucus production, heavy colonization of the airway, and transmission of the bacteria between hosts. As in humans, baboons demonstrate age-related differences in clinical presentation, with younger animals experiencing more severe disease. We examined the histopathology of 5- to 6-week-old baboons, with the findings being similar to those reported for fatal human infant cases. In juvenile baboons, we found that the disease is highly inflammatory and concentrated to the lungs with signs of disease that would typically be diagnosed as acute respiratory distress syndrome (ARDS) and bronchopneumonia. In contrast, no significant pathology was observed in the trachea. Histopathological changes in the trachea were limited to cellular infiltrates and mucus production. Immunohistostaining revealed that the bacteria were localized to the surface of the ciliated epithelium in the conducting airways. Our observations provide important insights into the pathology of pertussis in typical, severe but nonfatal pertussis cases in a very relevant animal model.

scholarly journals Nidovirus-Associated Proliferative Pneumonia in the Green Tree Python (Morelia viridis)

2017 ◽  
Vol 91 (21) ◽  
Author(s):  
Eva Dervas ◽  
Jussi Hepojoki ◽  
Andrea Laimbacher ◽  
Fernando Romero-Palomo ◽  
Christine Jelinek ◽  
...  
Keyword(s):  
Respiratory Tract ◽  
Lung Tissue ◽  
Natural Infection ◽  
Primary Cultures ◽  
Clinical Signs ◽  
Pathological Examination ◽  
The Novel ◽  
Isolation And Identification ◽  
Mucus Production ◽  
Content Type

ABSTRACT In 2014 we observed a noticeable increase in the number of sudden deaths among green tree pythons (Morelia viridis). Pathological examination revealed the accumulation of mucoid material within the airways and lungs in association with enlargement of the entire lung. We performed a full necropsy and histological examination on 12 affected green tree pythons from 7 different breeders to characterize the pathogenesis of this mucinous pneumonia. By histology we could show a marked hyperplasia of the airway epithelium and of faveolar type II pneumocytes. Since routine microbiological tests failed to identify a causative agent, we studied lung tissue samples from a few diseased snakes by next-generation sequencing (NGS). From the NGS data we could assemble a piece of RNA genome whose sequence was <85% identical to that of nidoviruses previously identified in ball pythons and Indian pythons. We then employed reverse transcription-PCR to demonstrate the presence of the novel nidovirus in all diseased snakes. To attempt virus isolation, we established primary cultures of Morelia viridis liver and brain cells, which we inoculated with homogenates of lung tissue from infected individuals. Ultrastructural examination of concentrated cell culture supernatants showed the presence of nidovirus particles, and subsequent NGS analysis yielded the full genome of the novel virus Morelia viridis nidovirus (MVNV). We then generated an antibody against MVNV nucleoprotein, which we used alongside RNA in situ hybridization to demonstrate viral antigen and RNA in the affected lungs. This suggests that in natural infection MVNV damages the respiratory tract epithelium, which then results in epithelial hyperplasia, most likely as an exaggerated regenerative attempt in association with increased epithelial turnover. IMPORTANCE Novel nidoviruses associated with severe respiratory disease were fairly recently identified in ball pythons and Indian pythons. Herein we report on the isolation and identification of a further nidovirus from green tree pythons (Morelia viridis) with fatal pneumonia. We thoroughly characterized the pathological changes in the infected individuals and show that nidovirus infection is associated with marked epithelial proliferation in the respiratory tract. We speculate that this and the associated excess mucus production can lead to the animals' death by inhibiting normal gas exchange in the lungs. The virus was predominantly detected in the respiratory tract, which renders transmission via the respiratory route likely. Nidoviruses cause sudden outbreaks with high rates of mortality in breeding collections, and most affected snakes die without prior clinical signs. These findings, together with those of other groups, indicate that nidoviruses are a likely cause of severe pneumonia in pythons.

scholarly journals Development of a Contemporary Animal Model of Candida albicans-Associated Denture Stomatitis Using a Novel Intraoral Denture System

2012 ◽  
Vol 80 (5) ◽  
pp. 1736-1743 ◽  
Author(s):  
Clorinda C. Johnson ◽  
Alika Yu ◽  
Heeje Lee ◽  
Paul L. Fidel ◽  
Mairi C. Noverr
Keyword(s):  
Animal Model ◽  
Candida Albicans ◽  
Biofilm Formation ◽  
Time Course ◽  
Clinical Signs ◽  
Clinical Score ◽  
Content Type ◽  
Denture Stomatitis ◽  
Relevant Animal Model ◽  
Repeated Sampling

ABSTRACTDenture stomatitis (DS) is a fungal infection characterized by inflammation of the oral mucosa in direct contact with the denture and affects up to 50% of denture wearers. Despite the prevalence, very little is known about the role of fungal or host factors that contribute to pathogenesis. Recently, we developed a novel intraoral denture system for rodent research. This denture system consists of custom-fitted fixed and removable parts to allow repeated sampling and longitudinal studies. The purpose of this study was to use this denture system to develop a clinically relevant animal model of DS. To establish DS, rats were inoculated with pelletedCandida albicans, which resulted in sustained colonization of the denture and palate for 8 weeks postinoculation. Biofilm formation on the denture was observed by week 4 and on the palate by week 6 postinoculation. Rats were monitored for clinical signs of disease by assigning a clinical score after macroscopic examination of the palate tissue according to Newton's method. By week 4 postinoculation, the majority of inoculated rats with dentures exhibited a clinical score of 1 (pinpoint erythema). By week 6 and week 8 postinoculation, increasing percentages of rats exhibited a clinical score of 2 (diffuse erythema/edema). Histological analysis of palate tissue demonstrated progressively increasing inflammatory cell recruitment throughout the time course of the infection. Palatal biofilm formation was commensurate with development of palatal erythema, which suggests a role for biofilm in the inflammatory response.

scholarly journals Experimental infection of indigenous North African goats with goatpox virus

2021 ◽  
Vol 63 (1) ◽  
Author(s):  
Jihane Hamdi ◽  
Zahra Bamouh ◽  
Mohammed Jazouli ◽  
Meryem Alhyane ◽  
Najet Safini ◽  
...  
Keyword(s):  
Antibody Response ◽  
Experimental Infection ◽  
Subcutaneous Tissue ◽  
Severe Disease ◽  
Clinical Signs ◽  
Economic Losses ◽  
North African ◽  
Cutaneous Lesions ◽  
Viral Dna ◽  
Goatpox Virus

Abstract Background Goatpox is a viral disease caused by infection with goatpox virus (GTPV) of the genus Capripoxvirus, Poxviridae family. Capripoxviruses cause serious disease to livestock and contribute to huge economic losses. Goatpox and sheeppox are endemic to Africa, particularly north of the Equator, the Middle East and many parts of Asia. GTPV and sheeppox virus are considered host-specific; however, both strains can cause clinical disease in either goats or sheep with more severe disease in the homologous species and mild or sub-clinical infection in the other. Goatpox has never been reported in Morocco, Algeria or Tunisia despite the huge population of goats living in proximity with sheep in those countries. To evaluate the susceptibility and pathogenicity of indigenous North African goats to GTPV infection, we experimentally inoculated eight locally bred goats with a virulent Vietnamese isolate of GTPV. Two uninfected goats were kept as controls. Clinical examination was carried out daily and blood was sampled for virology and for investigating the antibody response. After necropsy, tissues were collected and assessed for viral DNA using real-time PCR. Results Following the experimental infection, all inoculated goats displayed clinical signs characteristic of goatpox including varying degrees of hyperthermia, loss of appetite, inactivity and cutaneous lesions. The infection severely affected three of the infected animals while moderate to mild disease was noticed in the remaining goats. A high antibody response was developed. High viral DNA loads were detected in skin crusts and nodules, and subcutaneous tissue at the injection site with cycle threshold (Ct) values ranging from 14.6 to 22.9, while lower viral loads were found in liver and lung (Ct = 35.7 and 35.1). The results confirmed subcutaneous tropism of the virus. Conclusion Clinical signs of goatpox were reproduced in indigenous North African goats and confirmed a high susceptibility of the North African goat breed to GTPV infection. A clinical scoring system is proposed that can be applied in GTPV vaccine efficacy studies.

scholarly journals Treatment of Experimental Allergic Neuritis With Prednisolone

1987 ◽  
Vol 14 (1) ◽  
pp. 46-49 ◽  
Author(s):  
T.E. Feasby ◽  
J.J. Gilbert ◽  
A.F. Hahn ◽  
D.S. Lovgren
Keyword(s):  
Microscopic Examination ◽  
Severe Disease ◽  
Clinical Signs ◽  
Clinical Disease ◽  
Rapid Recovery ◽  
Experimental Allergic Neuritis ◽  
Nerve Roots ◽  
Lewis Rats ◽  
Experimental Allergic ◽  
Allergic Neuritis

Abstract:Experimental allergic neuritis (EAN) in Lewis rats was treated with prednisolone given prophylactically or therapeutically. Rats treated from the time of immunization with myelin or after the establishment of clinical disease improved more rapidly than controls. Treatment at the onset of clinical signs resulted in less severe disease and more rapid recovery. Rats treated just prior to the onset of clinical signs (day 10) did not develop significant clinical disease and appeared to have less inflammation in their nerves and nerve roots on microscopic examination.

Experimental delayed radiation necrosis of the brain

1979 ◽  
Vol 51 (5) ◽  
pp. 587-596 ◽  
Author(s):  
Albert N. Martins ◽  
Ralph E. Severance ◽  
James M. Henry ◽  
Thomas F. Doyle
Keyword(s):  
Rhesus Monkeys ◽  
Radiation Necrosis ◽  
Clinical Signs ◽  
Control Group ◽  
Content Type ◽  
Brain Irradiation ◽  
Primate Brain ◽  
High Doses ◽  
The Brain ◽  
Male Rhesus

✓ The authors have designed an experiment to detect a hitherto unrecognized interaction between high doses of the glucocorticoid, dexamethasone, and brain irradiation. Eighteen juvenile male rhesus monkeys received 1800 rads to the whole brain in 8.5 minutes. For 1½ days before and 10½ days after the irradiation, nine animals received approximately 2.9 mg/kg/day of dexamethasone intramuscularly in addition to irradiation, while the remaining nine animals served as the control group and received saline. All animals eventually developed a progressive neurological syndrome, and died of delayed radiation necrosis of the brain. The two groups were compared with regard to latency to onset of clinical signs, survival time, and number, distribution, and location of lesions of radionecrosis. Large doses of dexamethasone did not alter the susceptibility of the primate brain to delayed radiation necrosis. Detailed morphological study of the radionecrotic lesions supports the hypothesis that most, if not all, of the lesions develop as the consequence of injury to blood vessels.

scholarly journals Changes in Antigen-Specific Cytokine and Chemokine Responses to Plasmodium falciparum Antigens in a Highland Area of Kenya after a Prolonged Absence of Malaria Exposure

2014 ◽  
Vol 82 (9) ◽  
pp. 3775-3782 ◽  
Author(s):  
Lyticia A. Ochola ◽  
Cyrus Ayieko ◽  
Lily Kisia ◽  
Ng'wena G. Magak ◽  
Estela Shabani ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Severe Disease ◽  
Clinical Malaria ◽  
Necrosis Factor Alpha ◽  
Content Type ◽  
Highland Area ◽  
Cytokine Responses ◽  
Increased Risk ◽  
Tnf Α ◽  
Ifn Γ

ABSTRACTIndividuals naturally exposed toPlasmodium falciparumlose clinical immunity after a prolonged lack of exposure.P. falciparumantigen-specific cytokine responses have been associated with protection from clinical malaria, but the longevity ofP. falciparumantigen-specific cytokine responses in the absence of exposure is not well characterized. A highland area of Kenya with low and unstable malaria transmission provided an opportunity to study this question. The levels of antigen-specific cytokines and chemokines associated in previous studies with protection from clinical malaria (gamma interferon [IFN-γ], interleukin-10 [IL-10], and tumor necrosis factor alpha [TNF-α]), with increased risk of clinical malaria (IL-6), or with pathogenesis of severe disease in malaria (IL-5 and RANTES) were assessed by cytometric bead assay in April 2008, October 2008, and April 2009 in 100 children and adults. During the 1-year study period, none had an episode of clinicalP. falciparummalaria. Two patterns of cytokine responses emerged, with some variation by antigen: a decrease at 6 months (IFN-γ and IL-5) or at both 6 and 12 months (IL-10 and TNF-α) or no change over time (IL-6 and RANTES). These findings document thatP. falciparumantigen-specific cytokine responses associated in prior studies with protection from malaria (IFN-γ, TNF-α, and IL-10) decrease significantly in the absence ofP. falciparumexposure, whereas those associated with increased risk of malaria (IL-6) do not. The study findings provide a strong rationale for future studies of antigen-specific IFN-γ, TNF-α, and IL-10 responses as biomarkers of increased population-level susceptibility to malaria after prolonged lack ofP. falciparumexposure.

Age-related changes in the proportion of intracranial cerebrospinal fluid space measured using volumetric computerized tomography scanning

2002 ◽  
Vol 97 (3) ◽  
pp. 607-610 ◽  
Author(s):  
Hiroshi Wanifuchi ◽  
Takashi Shimizu ◽  
Takashi Maruyama
Keyword(s):  
Cerebrospinal Fluid ◽  
Computerized Tomography ◽  
Ct Scanning ◽  
Volume Measurement ◽  
Intracranial Volume ◽  
Content Type ◽  
Standard Curve ◽  
Age Related ◽  
Fine Print ◽  
Age Related Changes

Object. The purpose of this study was to establish a standard curve to demonstrate normal age-related changes in the proportion of intracranial cerebrospinal fluid (CSF) space in intracranial volume (ICV) during each decade of life. Methods. Using volumetric computerized tomography (CT) scanning and computer-guided volume measurement software, ICV and cerebral parenchymal volume (CPV) for each decade of life were measured and the intracranial CSF ratio was calculated by the following formula: percentage of CSF = (ICV − CPV)/ICV × 100%. The standard curve for age-related changes in normal percentages of intracranial CSF was obtained. Conclusions. Based on this standard curve, the percentage of intracranial CSF rapidly increased after the sixth decade, seeming to reflect the brain atrophy that accompanies increased age.

scholarly journals Kinome Expansion in theFusarium oxysporumSpecies Complex Driven by Accessory Chromosomes

mSphere ◽  
2018 ◽  
Vol 3 (3) ◽  
Author(s):  
Gregory A. DeIulio ◽  
Li Guo ◽  
Yong Zhang ◽  
Jonathan M. Goldberg ◽  
H. Corby Kistler ◽  
...  
Keyword(s):  
Fusarium Oxysporum ◽  
Species Complex ◽  
Severe Disease ◽  
Cellular Responses ◽  
Human Pathogens ◽  
Content Type ◽  
Evolutionary Forces ◽  
Environmental Signal ◽  
Wide Range ◽  
Opportunistic Fungal Pathogen

ABSTRACTTheFusarium oxysporumspecies complex (FOSC) is a group of soilborne pathogens causing severe disease in more than 100 plant hosts, while individual strains exhibit strong host specificity. Both chromosome transfer and comparative genomics experiments have demonstrated that lineage-specific (LS) chromosomes contribute to the host-specific pathogenicity. However, little is known about the functional importance of genes encoded in these LS chromosomes. Focusing on signaling transduction, this study compared the kinomes of 12F. oxysporumisolates, including both plant and human pathogens and 1 nonpathogenic biocontrol strain, with 7 additional publicly available ascomycete genomes. Overall,F. oxysporumkinomes are the largest, facilitated in part by the acquisitions of the LS chromosomes. The comparative study identified 99 kinases that are present in almost all examined fungal genomes, forming the core signaling network of ascomycete fungi. Compared to the conserved ascomycete kinome, the expansion of theF. oxysporumkinome occurs in several kinase families such as histidine kinases that are involved in environmental signal sensing and target of rapamycin (TOR) kinase that mediates cellular responses. Comparative kinome analysis suggests a convergent evolution that shapes individualF. oxysporumisolates with an enhanced and unique capacity for environmental perception and associated downstream responses.IMPORTANCEIsolates ofFusarium oxysporumare adapted to survive a wide range of host and nonhost conditions. In addition,F. oxysporumwas recently recognized as the top emerging opportunistic fungal pathogen infecting immunocompromised humans. The sensory and response networks of these fungi undoubtedly play a fundamental role in establishing the adaptability of this group. We have examined the kinomes of 12F. oxysporumisolates and highlighted kinase families that distinguishF. oxysporumfrom other fungi, as well as different isolates from one another. The amplification of kinases involved in environmental signal relay and regulating downstream cellular responses clearly setsFusariumapart from otherAscomycetes. Although the functions of many of these kinases are still unclear, their specific proliferation highlights them as a result of the evolutionary forces that have shaped this species complex and clearly marks them as targets for exploitation in order to combat disease.

Craniopharyngioma in adults and children: a study of 122 surgical cases

2002 ◽  
Vol 97 (1) ◽  
pp. 3-11 ◽  
Author(s):  
Rémy Van Effenterre ◽  
Anne-Laure Boch
Keyword(s):  
Patient Survival ◽  
Postoperative Radiotherapy ◽  
Clinical Signs ◽  
Functional Results ◽  
Recurrence Risk ◽  
Tumor Removal ◽  
Content Type ◽  
Adults And Children ◽  
Fine Print

Object. This work is devoted to a 25-year retrospective study of 122 cases of craniopharyngiomas in adults and children treated and followed by the same neurosurgeon (R.V.E.). In this homogeneous series, the aim was total microsurgical removal of the tumor, without postoperative radiotherapy. Methods. The operation was performed via a frontopterional approach in 112 cases and a transsphenoidal approach in 10 cases. The tumor removal was considered total in 59%, subtotal in 29%, and partial in 12%. The surgical mortality rate was 2.5%. Even when tumor removal was not complete, radiotherapy was not systematically administered; it was reserved for cases of recurrence. The authors have studied clinical signs, operative characteristics, and ophthalmological, endocrinological, and functional outcomes, as well as recurrence risk and long-term patient survival. The mean follow-up period was 7 years. The functional results in these patients were excellent in 85%, good in 9%, fair in 5% (usually because of ophthalmological sequelae), and poor in 1%. Tumors recurred in 29 patients, but the salvage treatment, by operation or radiotherapy, was successful in 83%. The actuarial patient survival rate was 92% after 5 years and 85% after 10 years. Conclusions. These results compared favorably with the data reported in the literature, suggesting that radical surgery of craniopharyngiomas allows good outcome in terms of survival, full recovery, and quality of life for both adults and children.

Media portrayals of older employees: a success story?

2014 ◽  
Vol 27 (4) ◽  
pp. 583-597 ◽  
Author(s):  
Martine van Selm ◽  
Beatrice I.J.M. Van der Heijden
Keyword(s):  
Mass Media ◽  
Older Workers ◽  
Longitudinal Research ◽  
Empirical Studies ◽  
Empirical Work ◽  
Corporate Communication ◽  
Content Type ◽  
Media Portrayals ◽  
Older Employees ◽  
Age Related

Purpose – The purpose of this paper is to provide an analysis of how portrayals of older employees in mass media messages can help combating stereotypical beliefs on their employability. Design/methodology/approach – The authors conducted a systematic review of empirical studies on mass media portrayals of older employees in order to show what these reveal about the ways in which their employment status, occupation, job type, or work setting is portrayed. The approach builds upon theory on media portrayals, media effects, and stereotypes of older workers’ employability. Findings – This study shows that older employees in media portrayals, when present at all, are relatively often shown in higher-level professional roles, herewith overall, depicting an image that is positive, yet differs from stereotypical beliefs on their employability that are prevalent in working organizations. Research limitations/implications – Further empirical work is needed to more safely conclude on the prevalence of age-related portrayals of work and employment in mass media. In addition, longitudinal research is called for in order to better understand the possible causes for the way in which older employees are portrayed, as well as effects of age-related stereotyping in mass media and corporate communication outlets over time. Practical implications – This research sparks ideas about how new portrayals of older employees in mass media and corporate communication outlets can contribute to novel approaches to managing an aging and multi-generational workforce. Social implications – This study shows how working organizations can make use of the positive and powerful media portrayals of older employees, in order to activate normal and non-ageist behaviors toward them, and herewith, to increase their life-long employability. Originality/value – This study highlights the role of media portrayals of older employees in combating stereotypes about their employability.

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