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1.
J Thorac Imaging ; 39(2): 93-100, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37889562

RESUMEN

PURPOSE: To evaluate a novel deep learning (DL)-based automated coronary labeling approach for structured reporting of coronary artery disease according to the guidelines of the Society of Cardiovascular Computed Tomography (CT) on coronary CT angiography (CCTA). PATIENTS AND METHODS: A retrospective cohort of 104 patients (60.3 ± 10.7 y, 61% males) who had undergone prospectively electrocardiogram-synchronized CCTA were included. Coronary centerlines were automatically extracted, labeled, and validated by 2 expert readers according to Society of Cardiovascular CT guidelines. The DL algorithm was trained on 706 radiologist-annotated cases for the task of automatically labeling coronary artery centerlines. The architecture leverages tree-structured long short-term memory recurrent neural networks to capture the full topological information of the coronary trees by using a two-step approach: a bottom-up encoding step, followed by a top-down decoding step. The first module encodes each sub-tree into fixed-sized vector representations. The decoding module then selectively attends to the aggregated global context to perform the local assignation of labels. To assess the performance of the software, percentage overlap was calculated between the labels of the algorithm and the expert readers. RESULTS: A total number of 1491 segments were identified. The artificial intelligence-based software approach yielded an average overlap of 94.4% compared with the expert readers' labels ranging from 87.1% for the posterior descending artery of the right coronary artery to 100% for the proximal segment of the right coronary artery. The average computational time was 0.5 seconds per case. The interreader overlap was 96.6%. CONCLUSIONS: The presented fully automated DL-based coronary artery labeling algorithm provides fast and precise labeling of the coronary artery segments bearing the potential to improve automated structured reporting for CCTA.


Asunto(s)
Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Aprendizaje Profundo , Masculino , Humanos , Femenino , Angiografía por Tomografía Computarizada/métodos , Inteligencia Artificial , Estudios Retrospectivos , Angiografía Coronaria/métodos , Tomografía Computarizada por Rayos X/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen
2.
Front Oncol ; 11: 596499, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33763347

RESUMEN

Juvenile-onset recurrent respiratory papillomatosis (JoRRP) is a condition characterized by the repeated growth of benign exophytic papilloma in the respiratory tract. The course of the disease remains unpredictable: some children experience minor symptoms, while others require multiple interventions due to florid growth. Our study aimed to identify histologic severity risk factors in patients with JoRRP. Forty-eight children from two French pediatric centers were included retrospectively. Criteria for a severe disease were: annual rate of surgical endoscopy ≥ 5, spread to the lung, carcinomatous transformation or death. We conducted a multi-stage study with image analysis. First, with Hematoxylin and eosin (HE) digital slides of papilloma, we searched for morphological patterns associated with a severe JoRRP using a deep-learning algorithm. Then, immunohistochemistry with antibody against p53 and p63 was performed on sections of FFPE samples of laryngeal papilloma obtained between 2008 and 2018. Immunostainings were quantified according to the staining intensity through two automated workflows: one using machine learning, the other using deep learning. Twenty-four patients had severe disease. For the HE analysis, no significative results were obtained with cross-validation. For immunostaining with anti-p63 antibody, we found similar results between the two image analysis methods. Using machine learning, we found 23.98% of stained nuclei for medium intensity for mild JoRRP vs. 36.1% for severe JoRRP (p = 0.041); and for medium and strong intensity together, 24.14% for mild JoRRP vs. 36.9% for severe JoRRP (p = 0.048). Using deep learning, we found 58.32% for mild JoRRP vs. 67.45% for severe JoRRP (p = 0.045) for medium and strong intensity together. Regarding p53, we did not find any significant difference in the number of nuclei stained between the two groups of patients. In conclusion, we highlighted that immunochemistry with the anti-p63 antibody is a potential biomarker to predict the severity of the JoRRP.

3.
J Parasitol ; 103(6): 756-767, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28816609

RESUMEN

Neospirorchis (Digenea: "Spirorchiidae") are blood flukes of sea turtles. Trematodes tentatively identified as Neospirorchis sp. infect various sites within sea turtles inhabiting waters of the southeastern United States, but efforts to obtain specimens adequate for morphologic study has proven difficult. Two genetic targets, the internal transcribed spacer region of the ribosomal RNA gene and the partial mitochondrial cytochrome c oxidase subunit I gene, were used to investigate potential diversity among parasite specimens collected from stranded sea turtles. Sequence data were obtained from 215 trematode and egg specimens collected from 92 individual free-ranging cheloniid sea turtles comprising 4 host species. Molecular analysis yielded more than 20 different genotypes. We were able to assign 1 genotype to 1 of the 2 recognized species, Neospirorchis pricei Manter and Larson, 1950 . In many examples, genotypes exhibited host and site specificity. Our findings indicate considerable diversity of parasites resembling Neospirorchis with evidence of a number of uncharacterized blood flukes that require additional study.


Asunto(s)
Trematodos/clasificación , Infecciones por Trematodos/veterinaria , Tortugas/parasitología , Animales , Océano Atlántico , Biodiversidad , ADN de Helmintos/genética , ADN Intergénico/química , ADN Mitocondrial/genética , ADN Ribosómico/genética , Florida , Golfo de México , Especificidad del Huésped , Filogenia , Trematodos/genética , Trematodos/fisiología , Infecciones por Trematodos/parasitología
4.
Musculoskelet Sci Pract ; 28: 18-24, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28715298

RESUMEN

BACKGROUND: Investigations on 3D kinematics during spinal manipulation are widely reported for assessing motion data, task reliability and clinical effects. However the link between cavitation occurrence and specific kinematics remains questionable. OBJECTIVES: This paper investigates the 3D head-trunk kinematics during high velocity low amplitude (HVLA) manipulation for different practitioners with respect to the occurrence of cavitation. METHODS: Head-trunk 3D motions were sampled during HVLA manipulation in twenty asymptomatic volunteers manipulated by four practitioners with different seniority (years of experience). Four target levels were selected, C3 and C5 on each side, and were randomly allocated to the different practitioners. The data was recorded before, during and after each set of trial in each anatomical plane. The number of trials with cavitation occurrence was collected for each practitioner. RESULTS: The manipulation task was performed using extension, ipsilateral side bending and contra-lateral axial rotation independent of side or target level. The displayed angular motion magnitudes did not exceed normal active ROM. Regardless cavitation occurrence, wide variations were observed between practitioners, especially in terms of velocity and acceleration. Cavitation occurrence was related to several kinematics features (i.e. frontal ROM and velocity, sagittal acceleration) and practitioner experience. In addition, multilevel cavitation was observed regularly. CONCLUSIONS: Kinematics of cervical manipulation is dependent on practitioner and years of experience. Cavitation occurrence could be related to particular kinematics features. These aspects should be further investigated in order to improve teaching and learning of cervical manipulation technique.


Asunto(s)
Vértebras Cervicales/fisiopatología , Voluntarios Sanos/estadística & datos numéricos , Manipulación Espinal/métodos , Rango del Movimiento Articular/fisiología , Enfermedades de la Columna Vertebral/terapia , Adulto , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
5.
Spine (Phila Pa 1976) ; 40(15): E900-8, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25839386

RESUMEN

STUDY DESIGN: A prospective study was performed on the assessment of both thoracic and lumbar spine sagittal profiles (from C7 to S1). OBJECTIVE: To propose a new noninvasive method for measuring the spine curvatures in standing and lying prone positions and to analyze their relationship with various biometric characteristics. SUMMARY OF BACKGROUND DATA: Modifications of spine curvatures (i.e. lordosis or kyphosis) are of importance in the development of spinal disorders. Studies have emphasized the development of new devices to measure the spine sagittal profiles using a noninvasive and low-cost method. To date, it has not been applied for analyzing both lumbar and thoracic alterations for various positioning. METHODS: Seventy-five healthy subjects (mean 22.6 ± 4.3 yr) were recruited to participate in this study. Thoracic and lumbar sagittal profiles were assessed in standing and lying prone positions using a 3D digitizer. In addition, several biometric data were collected including maximal trunk isometric strength for flexion and extension movement. Statistical analysis consisted in data comparisons of spine profiles and a multivariate analysis including biometric features, to classify individuals considering low within- and high between-variability. RESULT: Kyphosis and lordosis angles decreased significantly from standing to lying prone position by an average of 13.4° and 16.6°, respectively. Multivariate analysis showed a sample clustering of 3 homogenous subgroups. The first group displayed larger lordosis and flexibility, and had low data values for height, weight, and strength. The second group had lower values than the overall trend of the whole sample, whereas the third group had larger score values for the torques, height, weight, waist, body mass index, and kyphosis angle but a reduced flexibility. CONCLUSION: The present results demonstrate a significant effect of the positioning on both thoracic and lumbar spine sagittal profiles and highlight the use of cluster analysis to categorize subgroups after biometric characteristics including curvature measurement. LEVEL OF EVIDENCE: N/A.


Asunto(s)
Vértebras Lumbares/anatomía & histología , Posición Prona/fisiología , Vértebras Torácicas/anatomía & histología , Adolescente , Adulto , Biometría , Estatura , Índice de Masa Corporal , Peso Corporal , Femenino , Voluntarios Sanos , Humanos , Imagenología Tridimensional , Contracción Isométrica , Cifosis/patología , Lordosis/patología , Vértebras Lumbares/fisiología , Masculino , Fuerza Muscular , Músculo Esquelético/fisiología , Estudios Prospectivos , Rango del Movimiento Articular , Vértebras Torácicas/fisiología , Torque , Torso/fisiología , Adulto Joven
6.
Vet J ; 201(3): 257-64, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24951264

RESUMEN

Tortoise mycoplasmosis is one of the most extensively characterized infectious diseases of chelonians. A 1989 outbreak of upper respiratory tract disease (URTD) in free-ranging Agassiz's desert tortoises (Gopherus agassizii) brought together an investigative team of researchers, diagnosticians, pathologists, immunologists and clinicians from multiple institutions and agencies. Electron microscopic studies of affected tortoises revealed a microorganism in close association with the nasal mucosa that subsequently was identified as a new species, Mycoplasma agassizii. Over the next 24 years, a second causative agent, Mycoplasma testudineum, was discovered, the geographic distribution and host range of tortoise mycoplasmosis were expanded, diagnostic tests were developed and refined for antibody and pathogen detection, transmission studies confirmed the pathogenicity of the original M. agassizii isolate, clinical (and subclinical) disease and laboratory abnormalities were characterized, many extrinsic and predisposing factors were found to play a role in morbidity and mortality associated with mycoplasmal infection, and social behavior was implicated in disease transmission. The translation of scientific research into management decisions has sometimes led to undesirable outcomes, such as euthanasia of clinically healthy tortoises. In this article, we review and assess current research on tortoise mycoplasmosis, arguably the most important chronic infectious disease of wild and captive North American and European tortoises, and update the implications for management and conservation of tortoises in the wild.


Asunto(s)
Infecciones por Mycoplasma/veterinaria , Mycoplasma/fisiología , Infecciones del Sistema Respiratorio/veterinaria , Tortugas , Animales , Conservación de los Recursos Naturales , Infecciones por Mycoplasma/diagnóstico , Infecciones por Mycoplasma/epidemiología , Infecciones por Mycoplasma/etiología , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/etiología
7.
Man Ther ; 18(4): 339-44, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23375147

RESUMEN

The cervical spine exhibits considerable mobility, especially in axial rotation. Axial rotation exerts stress on anatomical structures, such as the vertebral artery which is commonly assessed during clinical examination. The literature is rather sparse concerning the in vivo three-dimensional segmental kinematics of the cervical spine. This study aimed at investigating the three-dimensional kinematics of the cervical spine during maximal passive head rotation with special emphasis on coupled motion. Twenty healthy volunteers participated in this study. Low-dose CT scans were conducted in neutral and in maximum axial rotation positions. Each separated vertebra was segmented semi automatically in these two positions. The finite helical-axis method was used to describe 3D motion between discrete positions. The mean (±SD) maximum magnitude of axial rotation between C0 and C1 was 2.5 ± 1.0° coupled with lateral flexion to the opposite side (5.0 ± 3.0°) and extension (12.0 ± 4.5°). At the C1-C2 level, the mean axial rotation was 37.5 ± 6.0° associated with lateral flexion to the opposite side (2.5 ± 6.0°) and extension (4.0 ± 6.0°). For the lower levels, axial rotation was found to be maximal at C4-C5 level (5.5 ± 1.0°) coupled with lateral flexion to the same side (-4.0 ± 2.5°). Extension was associated at levels C2-C3, C3-C4 and C4-C5, whereas flexion occurred between C5-C6 and C6-C7. Coupled lateral flexion occurred to the opposite side at the upper cervical spine and to the same side at the lower cervical spine.


Asunto(s)
Vértebras Cervicales/fisiología , Movimientos de la Cabeza/fisiología , Imagenología Tridimensional , Rango del Movimiento Articular/fisiología , Adulto , Fenómenos Biomecánicos , Vértebras Cervicales/diagnóstico por imagen , Femenino , Voluntarios Sanos , Humanos , Masculino , Valores de Referencia , Muestreo , Sensibilidad y Especificidad , Posición Supina , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
8.
Man Ther ; 18(4): 321-6, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23347773

RESUMEN

Segmental range of motion (ROM) during high-velocity manipulative spinal treatment is generally considered an important factor for the risk of adverse side effects, especially in the cervical spine region. Among the many techniques reported, the so-called multiple-component technique (MCT) is increasingly recommended. Such a technique is assumed to induce a relatively low three-dimensional (3D) segmental ROM compared with other techniques. The aims of our study are to quantify the 3D segmental ROM and to determine the pattern of motion between cervical vertebrae during the pre-manipulative position at the C4-C5 level. Ten healthy volunteers participated in this study. Two CT scans were conducted: one in a neutral position and the other in the pre-manipulative positioning. The manipulation using MCT was carried out by a skilled practitioner. During positioning, the head was rotated to the left and bent laterally to the right, and the upper cervical spine was rotated to the left and bent laterally to the right. In contrast, the lower cervical spine underwent right rotation and was bent laterally to the right. Segmental ROM was lower than the values obtained during active physiological rotation (P < 0.05). This study provides new insight into the 3D kinematics of the cervical spine during manipulation. An unexpected mechanism of counter-rotation was identified at the lower cervical levels and could represent a valuable and convenient way for precisely focussing on the level for manipulation.


Asunto(s)
Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/fisiología , Imagenología Tridimensional , Manipulación Espinal/métodos , Rango del Movimiento Articular/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Posicionamiento del Paciente , Radiografía , Muestreo , Sensibilidad y Especificidad , Adulto Joven
9.
Cochrane Database Syst Rev ; (5): CD001930, 2012 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-22592679

RESUMEN

BACKGROUND: Despite differences in how it is defined, there is a general consensus amongst clinicians and researchers that the sexual abuse of children and adolescents ('child sexual abuse') is a substantial social problem worldwide. The effects of sexual abuse manifest in a wide range of symptoms, including fear, anxiety, post-traumatic stress disorder and various externalising and internalising behaviour problems, such as inappropriate sexual behaviours. Child sexual abuse is associated with increased risk of psychological problems in adulthood. Cognitive-behavioural approaches are used to help children and their non-offending or 'safe' parent to manage the sequelae of childhood sexual abuse. This review updates the first Cochrane review of cognitive-behavioural approaches interventions for children who have been sexually abused, which was first published in 2006. OBJECTIVES: To assess the efficacy of cognitive-behavioural approaches (CBT) in addressing the immediate and longer-term sequelae of sexual abuse on children and young people up to 18 years of age. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2011 Issue 4); MEDLINE (1950 to November Week 3 2011); EMBASE (1980 to Week 47 2011); CINAHL (1937 to 2 December 2011); PsycINFO (1887 to November Week 5 2011); LILACS (1982 to 2 December 2011) and OpenGrey, previously OpenSIGLE (1980 to 2 December 2011). For this update we also searched ClinicalTrials.gov and the International Clinical Trials Registry Platform (ICTRP). SELECTION CRITERIA: We included randomised or quasi-randomised controlled trials of CBT used with children and adolescents up to age 18 years who had experienced being sexually abused, compared with treatment as usual, with or without placebo control. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed the eligibility of titles and abstracts identified in the search. Two review authors independently extracted data from included studies and entered these into Review Manager 5 software. We synthesised and presented data in both written and graphical form (forest plots). MAIN RESULTS: We included 10 trials, involving 847 participants. All studies examined CBT programmes provided to children or children and a non-offending parent. Control groups included wait list controls (n = 1) or treatment as usual (n = 9). Treatment as usual was, for the most part, supportive, unstructured psychotherapy. Generally the reporting of studies was poor. Only four studies were judged 'low risk of bias' with regards to sequence generation and only one study was judged 'low risk of bias' in relation to allocation concealment. All studies were judged 'high risk of bias' in relation to the blinding of outcome assessors or personnel; most studies did not report on these, or other issues of bias. Most studies reported results for study completers rather than for those recruited.Depression, post-traumatic stress disorder (PTSD), anxiety and child behaviour problems were the primary outcomes. Data suggest that CBT may have a positive impact on the sequelae of child sexual abuse, but most results were not statistically significant. Strongest evidence for positive effects of CBT appears to be in reducing PTSD and anxiety symptoms, but even in these areas effects tend to be 'moderate' at best. Meta-analysis of data from five studies suggested an average decrease of 1.9 points on the Child Depression Inventory immediately after intervention (95% confidence interval (CI) decrease of 4.0 to increase of 0.4; I(2) = 53%; P value for heterogeneity = 0.08), representing a small to moderate effect size. Data from six studies yielded an average decrease of 0.44 standard deviations on a variety of child post-traumatic stress disorder scales (95% CI 0.16 to 0.73; I(2) = 46%; P value for heterogeneity = 0.10). Combined data from five studies yielded an average decrease of 0.23 standard deviations on various child anxiety scales (95% CI 0.3 to 0.4; I(2) = 0%; P value for heterogeneity = 0.84). No study reported adverse effects. AUTHORS' CONCLUSIONS: The conclusions of this updated review remain the same as those when it was first published. The review confirms the potential of CBT to address the adverse consequences of child sexual abuse, but highlights the limitations of the evidence base and the need for more carefully conducted and better reported trials.


Asunto(s)
Abuso Sexual Infantil/terapia , Terapia Cognitivo-Conductual/métodos , Adolescente , Niño , Abuso Sexual Infantil/psicología , Preescolar , Femenino , Humanos , Lactante , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Opt Express ; 19(22): 21692-7, 2011 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-22109019

RESUMEN

The emission and waveguiding properties of individual GaN microwires as well as devices based on an n-GaN microwire/p-Si (100) junction were studied for relevance in optoelectronics and optical circuits. Pulsed photoluminescence of the GaN microwire excited in the transverse or longitudinal direction demonstrated gain. These n-type GaN microwires were positioned mechanically or by dielectrophoretic force onto pre-patterned electrodes on a p-type Si (100) substrate. Electroluminescence from this p-n point junction was characteristic of a heterostructure light-emitting diode. Additionally, waveguiding was observed along the length of the microwire for light originating from photoluminescence as well as from electroluminescence generated at the p-n junction.


Asunto(s)
Galio/química , Luz , Nanocables/química , Óptica y Fotónica , Silicio/química , Microscopía , Análisis Espectral
11.
Clin Vaccine Immunol ; 17(11): 1739-45, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20810678

RESUMEN

The precarious status of desert (Gopherus agassizii) and gopher (G. polyphemus) tortoises has resulted in conservation efforts that now include health assessment as an important component of management decision-making. Mycoplasmal upper respiratory tract disease (URTD) is one of very few diseases in chelonians for which comprehensive and rigorously validated diagnostic tests exist. In this study, serum samples obtained from eight Gopherus tortoises documented at necropsy to (i) be enzyme-linked immunosorbent assay (ELISA) seropositive using the PS6 antigen, (ii) be infected with Mycoplasma agassizii as indicated by direct isolation of the pathogen from the respiratory surfaces, and (iii) have histological lesions of mycoplasmal URTD were used to evaluate four distinct clinical isolates of M. agassizii as antigens for ELISA and Western blot analyses. Each animal sample reacted in the Western blot with its homologous M. agassizii strain, but recognition of heterologous M. agassizii strains was variable. Further, individual animals varied significantly with respect to the specific proteins recognized by the humoral immune response. An additional 114 Gopherus serum samples were evaluated using ELISA antigens prepared from the four distinct M. agassizii strains; A405 values were significantly correlated (r² goodness of fit range, 0.708 to 0.771; P < 0.0001) for all antigens tested. The results confirm that strain variation is responsible for the observed differences between Western blot binding patterns. Thus, reliance on a single M. agassizii strain as an antigen in Western blot assays may provide false-negative results. This could have adverse consequences for the well-being of these environmentally sensitive hosts if false-negative animals were relocated to sites consisting of true-negative populations.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Técnicas Bacteriológicas/métodos , Variación Genética , Infecciones por Mycoplasma/veterinaria , Mycoplasma/clasificación , Mycoplasma/aislamiento & purificación , Tortugas/microbiología , Animales , Western Blotting/métodos , Ensayo de Inmunoadsorción Enzimática/métodos , Mycoplasma/inmunología , Infecciones por Mycoplasma/diagnóstico , Infecciones por Mycoplasma/inmunología
12.
Dis Aquat Organ ; 89(3): 237-59, 2010 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-20481091

RESUMEN

Spirorchiid trematodes are implicated as an important cause of stranding and mortality in sea turtles worldwide. However, the impact of these parasites on sea turtle health is poorly understood due to biases in study populations and limited or missing data for some host species and regions, including the southeastern United States. We examined necropsy findings and parasitological data from 89 loggerhead Caretta caretta and 59 green turtles Chelonia mydas that were found dead or moribund (i.e. stranded) in Florida (USA) and evaluated the role of spirorchiidiasis in the cause of death. High prevalence of infection in the stranding population was observed, and most infections were regarded as incidental to the cause of death. Spirorchiidiasis was causal or contributory to death in some cases; however, notable host injury and/or large numbers of parasites were observed in some animals, including nutritionally robust turtles, with no apparent relationship to cause of death. New spirorchiid species records for the region were documented and identified genera included Neospirorchis, Hapalotrema, Carettacola, and Learedius. Parasites inhabited and were associated with injury and inflammation in a variety of anatomic locations, including large arteries, the central nervous system, endocrine organs, and the gastrointestinal tract. These findings provide essential information on the diversity of spirorchiids found in Florida sea turtles, as well as prevalence of infection and the spectrum of associated pathological lesions. Several areas of needed study are identified with regard to potential health implications in the turtle host, and findings caution against over-interpretation in individual cases.


Asunto(s)
Trematodos/clasificación , Infecciones por Trematodos/veterinaria , Tortugas , Animales , Florida/epidemiología , Infecciones por Trematodos/epidemiología , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/patología
13.
Ecology ; 91(5): 1257-62, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20503858

RESUMEN

Since the early 1990s, morbidity and mortality in tortoise populations have been associated with a transmissible, mycoplasmal upper respiratory tract disease (URTD). Although the etiology, transmission, and diagnosis of URTD have been extensively studied, little is known about the dynamics of disease transmission in free-ranging tortoise populations. To understand the transmission dynamics of Mycoplasma agassizii, the primary etiological agent of URTD in wild tortoise populations, we studied 11 populations of free-ranging gopher tortoises (Gopherus polyphemus; n = 1667 individuals) over five years and determined their exposure to the pathogen by serology, by clinical signs, and by detection of the pathogen in nasal lavages. Adults tortoises (n = 759) were 11 times more likely to be seropositive than immature animals (n = 242) (odds ratio = 10.6, 95% CI = 5.7-20, P < 0.0001). Nasal discharge was observed in only 1.4% (4/296) of immature tortoises as compared with 8.6% (120/1399) of adult tortoises. Nasal lavages from all juvenile tortoises (n = 283) were negative by PCR for mycoplasmal pathogens associated with URTD. We tested for spatial segregation among tortoise burrows by size class and found no consistent evidence of clustering of either juveniles or adults. We suggest that the social behavior of tortoises plays a critical role in the spread of URTD in wild populations, with immature tortoises having minimal interactions with adult tortoises, thereby limiting their exposure to the pathogen. These findings may have broader implications for modeling horizontally transmitted diseases in other species with limited parental care and emphasize the importance of incorporating animal behavior parameters into disease transmission studies to better characterize the host-pathogen dynamics.


Asunto(s)
Infecciones por Mycoplasma/veterinaria , Infecciones del Sistema Respiratorio/veterinaria , Conducta Social , Tortugas , Animales , Conservación de los Recursos Naturales , Florida , Infecciones por Mycoplasma/transmisión , Infecciones del Sistema Respiratorio/microbiología , Infecciones del Sistema Respiratorio/transmisión
14.
J Parasitol ; 96(4): 752-7, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20496958

RESUMEN

Marine spirorchiid trematodes are associated with morbidity and mortality in sea turtles worldwide. The intermediate hosts remain unknown, and discovery efforts are hindered by the large number and great diversity of potential hosts within sea turtle habitats, as well the potential for low prevalence and overdispersion. A high-throughput DNA extraction and polymerase chain reaction-based method was developed to detect the internal transcribed spacer 2 (ITS2) region of the ribosomal gene of 2 spirorchiid genera, Learedius and Hapalotrema , within pooled samples of gastropod tissues. A model system consisting of freshwater snail ( Pomacea bridgesii ) tissues and DNA extracts spiked with adult Learedius learedi and known quantities of spirorchiid DNA was used to develop and test the technique. Threshold of detection was found to be equivalent to an early prepatent infection within 1.5 g of gastropod tissue. This technique was used to screen approximately 25 species of marine gastropods at a captive facility where green turtles ( Chelonia mydas ) become infected by L. learedi . The parasite was detected in a sample of knobby keyhole limpet ( Fissurella nodosa ), thus providing the first evidence of an intermediate host for a marine spirorchiid trematode. This technique has many potential applications in trematode life cycle discovery studies.


Asunto(s)
ADN de Helmintos/aislamiento & purificación , Gastrópodos/parasitología , Reacción en Cadena de la Polimerasa/veterinaria , Trematodos/aislamiento & purificación , Animales , Trematodos/clasificación , Trematodos/genética
15.
Comp Immunol Microbiol Infect Dis ; 32(5): 379-94, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18242703

RESUMEN

Megachiropteran bats are biologically important both as endangered species and reservoirs for emerging human pathogens. Reliable detection of antibodies to specific pathogens in bats is thus epidemiologically critical. Eight variable flying foxes (Pteropus hypomelanus) were immunized with 2,4-dinitrophenylated bovine serum albumin (DNP-BSA). Each bat received monthly inoculations for 2 months. Affinity-purified IgG was used for production of polyclonal and monoclonal anti-variable flying fox IgG antibodies. ELISA and western blot analysis were used to monitor immune responses and for assessment of polyclonal and monoclonal antibody species cross-reactivity. Protein G, polyclonal antibodies, and monoclonal antibodies detected specific anti-DNP antibody responses in immunized variable flying foxes, with protein G being the most sensitive, followed by monoclonal antibodies and then polyclonal antibodies. While the polyclonal antibody was found to cross-react well against IgG of all bat species tested, some non-specific background was observed. The monoclonal antibody was found to cross-react well against IgG of six other species in the genus Pteropus and to cross-react less strongly against IgG from Eidolon helvum or Phyllostomus hastatus. Protein G distinguished best between vaccinated and unvaccinated bats, and these results validate the use of protein G for detection of bat IgG. Monoclonal antibodies developed in this study recognized immunoglobulins from other members of the genus Pteropus well, and may be useful in applications where specific detection of Pteropus IgG is needed.


Asunto(s)
Anticuerpos Antiidiotipos/inmunología , Anticuerpos Monoclonales/inmunología , Formación de Anticuerpos/inmunología , Proteínas Bacterianas/inmunología , Quirópteros/inmunología , Animales , Anticuerpos Antiidiotipos/metabolismo , Proteínas Bacterianas/metabolismo , Quirópteros/sangre , Reacciones Cruzadas/inmunología , Dinitrofenoles/inmunología , Albúmina Sérica Bovina/inmunología , Vacunación
17.
Antiviral Res ; 80(1): 77-80, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18485494

RESUMEN

Parapoxviruses of seals and sea lions are commonly encountered pathogens with zoonotic potential. The antiviral activity of the antiviral compounds isatin-beta-thiosemicarbazone, rifampicin, acyclovir, cidofovir and phosphonoacetic acid against a parapoxvirus (SLPV-1) isolated from a Californian sea lions (Zalophus californianus) was evaluated. Cidofovir was able to reduce virus-induced cytopathic effect of SLPV-1 in confluent monolayers when used in concentrations greater than 2microg/ml. A decreasing virus yield was observed in the presence of increasing concentrations of cidofovir, which confirmed the ability of cidofovir to inhibit SLPV-1 replication. The in vitro efficacy of cidofovir against SLPV-1 indicates the therapeutic potential of cidofovir for the treatment of infections of humans and pinnipeds with parapoxviruses of seals and sea lions. This study confirms the previously proposed therapeutic potential of cidofovir for the treatment of parapoxvirus infections.


Asunto(s)
Antivirales/farmacología , Citosina/análogos & derivados , Organofosfonatos/farmacología , Parapoxvirus/efectos de los fármacos , Infecciones por Poxviridae/veterinaria , Leones Marinos/virología , Animales , Células Cultivadas , Cidofovir , Efecto Citopatogénico Viral/efectos de los fármacos , Citosina/farmacología , Riñón/citología , Riñón/virología , Pruebas de Sensibilidad Microbiana , Parapoxvirus/clasificación , Parapoxvirus/fisiología , Infecciones por Poxviridae/virología
18.
Vet Immunol Immunopathol ; 124(3-4): 322-31, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18499267

RESUMEN

Disease has become an increasingly important issue for wildlife management over the past two decades. Adequate surveillance is fundamental for disease prevention and control, thus there is an increasing need for diagnostic assays for wildlife management. The objective of this study was to evaluate the performance of a field-portable biosensor adapted for rapid detection of specific antibodies in tortoise plasma that reflect a history of exposure to Mycoplasma agassizii, which is an agent of tortoise upper respiratory tract disease. Banked plasma samples were tested in two blinded trials, and the parameters that define the reliability of a diagnostic test were estimated based on externally validated tortoise plasma controls. The mean sensitivity of the biosensor (ability to identify exposed tortoises in the group of all exposed individuals) was 78%; the mean specificity (unexposed individuals with negative test result, out of all unexposed individuals tested) was 73%; the mean positive predictive value (exposed individuals with positive test, out of all individuals with positive test) was 82%; the mean negative predictive value (unexposed individuals with negative test, out of all individuals with negative test) was 68%. In a 15-min field-portable format, the biosensor was able to discriminate between true seropositive (n=34) and true seronegative (n=23) tortoise plasma with overall accuracy of 84%. The goals established for the tortoise population can help managers decide whether potential diagnostic errors should impact management decision-making, and whether the benefits of the field-portable format of the biosensor assay outweigh any potential disadvantages.


Asunto(s)
Técnicas Biosensibles/veterinaria , Infecciones por Mycoplasma/veterinaria , Mycoplasma/inmunología , Enfermedades Respiratorias/veterinaria , Tortugas/microbiología , Animales , Anticuerpos Antibacterianos/sangre , Infecciones por Mycoplasma/inmunología , Infecciones por Mycoplasma/microbiología , Valor Predictivo de las Pruebas , Enfermedades Respiratorias/inmunología , Enfermedades Respiratorias/microbiología , Sensibilidad y Especificidad , Estadísticas no Paramétricas
19.
Clin Vaccine Immunol ; 15(5): 843-51, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18367581

RESUMEN

Chelonid fibropapillomatosis-associated herpesvirus (CFPHV) is an alphaherpesvirus believed to cause marine turtle fibropapillomatosis (FP). A serodiagnostic assay was developed for monitoring sea turtle populations for CFPHV exposure. CFPHV glycoprotein H (gH) expressed in recombinant baculovirus was used in an enzyme-linked immunosorbent assay (ELISA) to detect virus-specific 7S turtle antibodies. Using captive-reared green turtles (Chelonia mydas) with no history of virus exposure as "known negatives" and others with experimentally induced FP as "known positives," the assay had 100% specificity but low sensitivity, as seroconversion was detected in only half of the turtles bearing experimentally induced tumors. Antibodies were detected only in samples collected after cutaneous fibropapillomas appeared, consistent with observations that tumors are significant sites of virion production and antigen expression and the possibility that prolonged/repeated virus shedding may be required for adequate stimulation of 7S antibody responses to gH. Natural routes of infection, however, may produce higher seroconversion rates. High gH antibody seroprevalences ( approximately 80%) were found among wild green turtles in three Florida localities with different FP prevalences, including one site with no history of FP. In addition, all eight loggerhead turtles (Caretta caretta) tested were seropositive despite FP being uncommon in this species. The possibility that CFPHV infection may be common relative to disease suggests roles for environmental and host factors as modulators of disease expression. Alternatively, the possibility of other antigenically similar herpesviruses present in wild populations cannot be excluded, although antibody cross-reactivity with the lung/eye/trachea disease-associated herpesvirus was ruled out in this study.


Asunto(s)
Baculoviridae/genética , Fibroma/epidemiología , Fibroma/veterinaria , Glicoproteínas/metabolismo , Infecciones por Herpesviridae/epidemiología , Infecciones por Herpesviridae/veterinaria , Neoplasias Cutáneas/veterinaria , Tortugas/virología , Animales , Ensayo de Inmunoadsorción Enzimática , Fibroma/diagnóstico , Glicoproteínas/genética , Infecciones por Herpesviridae/diagnóstico , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/virología , Infecciones Tumorales por Virus/diagnóstico , Infecciones Tumorales por Virus/epidemiología , Infecciones Tumorales por Virus/veterinaria
20.
J Vet Diagn Invest ; 19(5): 465-70, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17823388

RESUMEN

Antibodies directed against species-specific immunoglobulin G (IgG) have a broad range of applications in serologic and immunologic research and in the development of clinical assays. Validated anti-IgG antibodies for marine mammal species are in short supply. The objective of this study was to produce and validate antibodies with specificity for IgG of the common bottlenose dolphin (Tursiops truncatus). Bottlenose dolphin IgG was purified using protein G. Two mouse monoclonal antibodies and a rabbit polyclonal antibody were developed from mice and rabbits immunized with bottlenose dolphin IgG. The specificity of the monoclonal antibodies and the polyclonal antibody for bottlenose dolphin IgG was first verified by Western blot analysis and enzyme-linked immunosorbent assay (ELISA). For further validation, both monoclonal antibodies and the polyclonal antibody were incorporated in an indirect ELISA for the detection of the immune response of bottlenose dolphins to a vaccine antigen. Three bottlenose dolphins were immunized with a commercial Erysipelothrix rhusiopathiae vaccine, and serial blood samples were collected from all dolphins for measurement of levels of circulating antibodies. Seroconversion was observed in all 3 dolphins by use of both monoclonal antibodies and the polyclonal antibody. Circulating antibodies were detectable as early as 6 days after immunization in 1 dolphin. Peak antibody levels were detected 14 days after the immunization. The ability to detect seroconversion in all 3 immunized bottlenose dolphins firmly establishes the specificity of the monoclonal antibodies and the polyclonal antibody for IgG of the common bottlenose dolphin.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/inmunología , Delfín Mular/inmunología , Inmunoglobulina G/análisis , Inmunoglobulina G/inmunología , Animales , Especificidad de Anticuerpos , Erysipelothrix/inmunología , Infecciones por Erysipelothrix/inmunología , Masculino , Ratones , Conejos , Reproducibilidad de los Resultados
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