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BACKGROUND: In cancer patients, circulating cell-free DNA (ccfDNA) can contain tumor-derived DNA (ctDNA), which enables noninvasive diagnosis, real-time monitoring, and treatment susceptibility testing. However, ctDNA fractions are highly variable, which challenges downstream applications. Therefore, established preanalytical work flows in combination with cost-efficient and reproducible reference materials for ccfDNA analyses are crucial for analytical validity and subsequently for clinical decision-making. METHODS: We describe the efforts of the Innovative Medicines Initiative consortium CANCER-ID (http://www.cancer-id.eu) for comparing different technologies for ccfDNA purification, quantification, and characterization in a multicenter setting. To this end, in-house generated mononucleosomal DNA (mnDNA) from lung cancer cell lines carrying known TP53 mutations was spiked in pools of plasma from healthy donors generated from 2 different blood collection tubes (BCTs). ccfDNA extraction was performed at 15 partner sites according to their respective routine practice. Downstream analysis of ccfDNA with respect to recovery, integrity, and mutation analysis was performed centralized at 4 different sites. RESULTS: We demonstrate suitability of mnDNA as a surrogate for ccfDNA as a process quality control from nucleic acid extraction to mutation detection. Although automated extraction protocols and quantitative PCR-based quantification methods yielded the most consistent and precise results, some kits preferentially recovered spiked mnDNA over endogenous ccfDNA. Mutated TP53 fragments derived from mnDNA were consistently detected using both next-generation sequencing-based deep sequencing and droplet digital PCR independently of BCT. CONCLUSIONS: This comprehensive multicenter comparison of ccfDNA preanalytical and analytical work flows is an important contribution to establishing evidence-based guidelines for clinically feasible (pre)analytical work flows.
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Ácidos Nucleicos Libres de Células/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Recolección de Muestras de Sangre , Línea Celular Tumoral , Ácidos Nucleicos Libres de Células/química , Ácidos Nucleicos Libres de Células/normas , ADN Tumoral Circulante/sangre , Análisis Mutacional de ADN , Secuenciación de Nucleótidos de Alto Rendimiento/normas , Humanos , Neoplasias/genética , Neoplasias/patología , Nucleosomas/genética , Polimorfismo de Nucleótido Simple , Fase Preanalítica , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Estándares de Referencia , Proteína p53 Supresora de Tumor/genéticaRESUMEN
BACKGROUND: In human body fluids, microRNA (miRNA) can be found as circulating cell-free miRNA (cfmiRNA), as well as secreted into extracellular vesicles (EVmiRNA). miRNAs are being intensively evaluated as minimally invasive liquid biopsy biomarkers in patients with cancer. The growing interest in developing clinical assays for circulating miRNA necessitates careful consideration of confounding effects of preanalytical and analytical parameters. METHODS: By using reverse transcription quantitative real-time PCR and next-generation sequencing (NGS), we compared extraction efficiencies of 5 different protocols for cfmiRNA and 2 protocols for EVmiRNA isolation in a multicentric manner. The efficiency of the different extraction methods was evaluated by measuring exogenously spiked cel-miR-39 and 6 targeted miRNAs in plasma from 20 healthy individuals. RESULTS: There were significant differences between the tested methods. Although column-based extraction methods were highly effective for the isolation of endogenous miRNA, phenol extraction combined with column-based miRNA purification and ultracentrifugation resulted in lower quality and quantity of isolated miRNA. Among all extraction methods, the ubiquitously expressed miR-16 was represented with high abundance when compared with other targeted miRNAs. In addition, the use of miR-16 as an endogenous control for normalization of quantification cycle values resulted in a decreased variability of column-based cfmiRNA extraction methods. Cluster analysis of normalized NGS counts clearly indicated a method-dependent bias. CONCLUSIONS: The choice of plasma miRNA extraction methods affects the selection of potential miRNA marker candidates and mechanistic interpretation of results, which should be done with caution, particularly across studies using different protocols.
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MicroARN Circulante/sangre , MicroARN Circulante/aislamiento & purificación , Anciano , Animales , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/aislamiento & purificación , Caenorhabditis elegans/química , Fraccionamiento Químico/métodos , Vesículas Extracelulares/química , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodosRESUMEN
Circulating tumor cells (CTCs), potential precursors of most epithelial solid tumors, are mainly enriched by epithelial cell adhesion molecule (EpCAM)-dependent technologies. Hence, these approaches may overlook mesenchymal CTCs, considered highly malignant. Our aim was to establish a workflow to enrich and isolate patient-matched EpCAMhigh and EpCAMlow/negative CTCs within the same blood samples, and to investigate the phosphatidylinositol 3-kinase catalytic subunit alpha (PIK3CA) mutational status within single CTCs. We sequentially processed metastatic breast cancer (MBC) blood samples via CellSearch® (EpCAM-based) and via Parsortix™ (size-based) systems. After enrichment, cells captured in Parsortix™ cassettes were stained in situ for nuclei, cytokeratins, EpCAM and CD45. Afterwards, sorted cells were isolated via CellCelector™ micromanipulator and their genomes were amplified. Lastly, PIK3CA mutational status was analyzed by combining an amplicon-based approach with Sanger sequencing. In 54% of patients' blood samples both EpCAMhigh and EpCAMlow/negative cells were identified and successfully isolated. High genomic integrity was observed in 8% of amplified genomes of EpCAMlow/negative cells vs. 28% of EpCAMhigh cells suggesting an increased apoptosis in the first CTC-subpopulation. Furthermore, PIK3CA hotspot mutations were detected in both EpCAMhigh and EpCAMlow/negative CTCs. Our workflow is suitable for single CTC analysis, permitting-for the first time-assessment of the heterogeneity of PIK3CA mutational status within patient-matched EpCAMhigh and EpCAMlow/negative CTCs.
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Neoplasias de la Mama , Fosfatidilinositol 3-Quinasa Clase I/sangre , Molécula de Adhesión Celular Epitelial/sangre , Citometría de Flujo/métodos , Mutación , Proteínas de Neoplasias , Células Neoplásicas Circulantes/metabolismo , Flujo de Trabajo , Neoplasias de la Mama/sangre , Neoplasias de la Mama/genética , Femenino , Humanos , Células MCF-7 , Proteínas de Neoplasias/sangre , Proteínas de Neoplasias/genéticaRESUMEN
FE65 is a cytosolic adapter protein and an important binding partner of amyloid precursor protein. Dependent on Thr668 phosphorylation in amyloid precursor protein, which influences amyloidogenic amyloid precursor protein processing, FE65 undergoes nuclear translocation, thereby transmitting a signal from the cell membrane to the nucleus. As this translocation may be relevant in Alzheimer disease, and as FE65 consists of three protein-protein interaction domains able to bind and affect a variety of other proteins and downstream signaling pathways, the identification of the FE65 interactome is of central interest in Alzheimer disease research. In this study, we identified 121 proteins as new potential FE65 interacting proteins in a pulldown/mass spectrometry approach using human post-mortem brain samples as protein pools for recombinantly expressed FE65. Co-immunoprecipitation assays further validated the interaction of FE65 with the candidates SV2A and SERCA2. In parallel, we investigated the whole cell proteome of primary hippocampal neurons from FE65/FE65L1 double knockout mice. Notably, the validated FE65 binding proteins were also found to be differentially abundant in neurons derived from the FE65 knockout mice relative to wild-type control neurons. SERCA2 is an important player in cellular calcium homeostasis, which was found to be up-regulated in double knockout neurons. Indeed, knock-down of FE65 in HEK293T cells also evoked an elevated sensitivity to thapsigargin, a stressor specifically targeting the activity of SERCA2. Thus, our results suggest that FE65 is involved in the regulation of intracellular calcium homeostasis. Whereas transfection of FE65 alone caused a typical dot-like phenotype in the nucleus, co-transfection of SV2A significantly reduced the percentage of FE65 dot-positive cells, pointing to a possible role for SV2A in the modulation of FE65 intracellular targeting. Given that SV2A has a signaling function at the presynapse, its effect on FE65 intracellular localization suggests that the SV2A/FE65 interaction might play a role in synaptic signal transduction.
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Encéfalo/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/metabolismo , Mapas de Interacción de Proteínas , Animales , Encéfalo/patología , Células Cultivadas , Embrión de Mamíferos , Células HEK293 , Humanos , Inmunoprecipitación , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/aislamiento & purificación , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/aislamiento & purificación , Neuronas/metabolismo , Neuronas/patología , Proteínas Nucleares/genética , Unión Proteica , Mapas de Interacción de Proteínas/genética , Sinapsis/genética , Sinapsis/metabolismoRESUMEN
The 2016 Warwick Agreement on femoroacetabular impingement (FAI) syndrome was convened to build an international, multidisciplinary consensus on the diagnosis and management of patients with FAI syndrome. 22 panel members and 1 patient from 9 countries and 5 different specialties participated in a 1-day consensus meeting on 29 June 2016. Prior to the meeting, 6 questions were agreed on, and recent relevant systematic reviews and seminal literature were circulated. Panel members gave presentations on the topics of the agreed questions at Sports Hip 2016, an open meeting held in the UK on 27-29 June. Presentations were followed by open discussion. At the 1-day consensus meeting, panel members developed statements in response to each question through open discussion; members then scored their level of agreement with each response on a scale of 0-10. Substantial agreement (range 9.5-10) was reached for each of the 6 consensus questions, and the associated terminology was agreed on. The term 'femoroacetabular impingement syndrome' was introduced to reflect the central role of patients' symptoms in the disorder. To reach a diagnosis, patients should have appropriate symptoms, positive clinical signs and imaging findings. Suitable treatments are conservative care, rehabilitation, and arthroscopic or open surgery. Current understanding of prognosis and topics for future research were discussed. The 2016 Warwick Agreement on FAI syndrome is an international multidisciplinary agreement on the diagnosis, treatment principles and key terminology relating to FAI syndrome.Author note The Warwick Agreement on femoroacetabular impingement syndrome has been endorsed by the following 25 clinical societies: American Medical Society for Sports Medicine (AMSSM), Association of Chartered Physiotherapists in Sports and Exercise Medicine (ACPSEM), Australasian College of Sports and Exercise Physicians (ACSEP), Austian Sports Physiotherapists, British Association of Sports and Exercise Medicine (BASEM), British Association of Sport Rehabilitators and Trainers (BASRaT), Canadian Academy of Sport and Exercise Medicine (CASEM), Danish Society of Sports Physical Therapy (DSSF), European College of Sports and Exercise Physicians (ECOSEP), European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA), Finnish Sports Physiotherapist Association (SUFT), German-Austrian-Swiss Society for Orthopaedic Traumatologic Sports Medicine (GOTS), International Federation of Sports Physical Therapy (IFSPT), International Society for Hip Arthroscopy (ISHA), Groupo di Interesse Specialistico dell'A.I.F.I., Norwegian Association of Sports Medicine and Physical Activity (NIMF), Norwegian Sports Physiotherapy Association (FFI), Society of Sports Therapists (SST), South African Sports Medicine Association (SASMA), Sports Medicine Australia (SMA), Sports Doctors Australia (SDrA), Sports Physiotherapy New Zealand (SPNZ), Swedish Society of Exercise and Sports Medicine (SFAIM), Swiss Society of Sports Medicine (SGMS/SGSM), Swiss Sports Physiotherapy Association (SSPA).
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Pinzamiento Femoroacetabular/diagnóstico , Pinzamiento Femoroacetabular/terapia , Acetábulo/fisiopatología , Congresos como Asunto , Consenso , Articulación de la Cadera/fisiopatología , Humanos , SociedadesRESUMEN
The Hamilton principle is applied to deduce the free vibration frequencies of a cantilever single-walled carbon nanotube (SWCNT) in the presence of an added mass, which can be distributed along an arbitrary part of the span. The nonlocal elasticity theory by Eringen has been employed, in order to take into account the nanoscale effects. An exact formulation leads to the equations of motion, which can be solved to give the frequencies and the corresponding vibration modes. Moreover, two approximate semianalytical methods are also illustrated, which can provide quick parametric relationships. From a more practical point of view, the problem of detecting the mass of the attached particle has been solved by calculating the relative frequency shift due to the presence of the added mass: from it, the mass value can be easily deduced. The paper ends with some numerical examples, in which the nonlocal effects are thoroughly investigated.
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BACKGROUND: Among emerging circulating biomarkers, miRNA has the potential to detect lung cancer and follow the course of the disease. However, miRNA analysis deserves further standardization before implementation into clinical trials or practice. Here, we performed international ring experiments to explore (pre)-analytical factors relevant to the outcome of miRNA blood tests in the context of the EU network CANCER-ID. METHODS: Cell-free (cfmiRNA) and extracellular vesicle-derived miRNA (EVmiRNA) were extracted using the miRNeasy Serum/Plasma Advanced, and the ExoRNeasy Maxi kit, respectively, in a plasma cohort of 27 NSCLC patients and 20 healthy individuals. Extracted miRNA was investigated using small RNA sequencing and hybridization platforms. Validation of the identified miRNA candidates was performed using quantitative PCR. RESULTS: We demonstrate the highest read counts in healthy individuals and NSCLC patients using QIAseq. Moreover, QIAseq showed 15.9% and 162.9% more cfmiRNA and EVmiRNA miRNA counts, respectively, in NSCLC patients compared to healthy control samples. However, a systematic comparison of selected miRNAs revealed little agreement between high-throughput platforms, thus some miRNAs are detected with one technology, but not with the other. Adding to this, 35% (9 of 26) of selected miRNAs in the cfmiRNA and 42% (11 of 26) in the EVmiRNA fraction were differentially expressed by at least one qPCR platform; about half of the miRNAs (54%) were concordant for both platforms. CONCLUSIONS: Changing of (pre)-analytical methods of miRNA analysis has a significant impact on blood test results and is therefore a major confounding factor. In addition, to confirm miRNA biomarker candidates screening studies should be followed by targeted validation using an independent platform or technology.
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OBJECTIVE: To establish the prevalence of lesions of the labrum and articular cartilage of the hip in asymptomatic elite soccer players by performing 3T magnetic resonance imaging. METHODS: Eighty-four asymptomatic hips of 42 professional soccer players were evaluated. Male subjects older than 18 years were included. Cam and pincer deformity were defined as an alpha angle greater than 55 degrees and a lateral centre edge angle greater than 39 degrees, respectively. Labral injuries were classified with the Czerny classification and cartilage damage was classified with the Outerbridge classification. Specific statistical tests were used to establish the relationship between anatomical variances of the hip and the presence of chondral and labral injuries. RESULTS: FAI morphology prevalence was 25%. Abnormalities such as cam (22.5%) and labral injuries (33.8%) were found. Those cases with reported labral injury were predominantly intrasubstance damage (18.8%). Anatomical features of FAI were found to be related to lesions of the femoral cartilage (P<.001), chondrolabral damage (P=.042), or both injuries (P<.001). CONCLUSION: Asymptomatic labral or cartilaginous injuries of the hip were reported in 25% of the included professional soccer players. These injuries were associated with anatomical features of FAI.
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Cartílago Articular/diagnóstico por imagen , Cartílago Articular/lesiones , Lesiones de la Cadera/diagnóstico por imagen , Lesiones de la Cadera/epidemiología , Imagen por Resonancia Magnética , Fútbol/lesiones , Traumatismos en Atletas/complicaciones , Traumatismos en Atletas/diagnóstico por imagen , Traumatismos en Atletas/epidemiología , Estudios Transversales , Pinzamiento Femoroacetabular/diagnóstico por imagen , Pinzamiento Femoroacetabular/etiología , Lesiones de la Cadera/complicaciones , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Prevalencia , Adulto JovenRESUMEN
We discuss the current status of liquid biopsy and its advantages and challenges with a focus on pre-analytical sample handling, technologies and workflows. The potential of circulating tumor cells and circulating tumor DNA is pointed out and an overview of corresponding technologies is given.
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Erythrocyte and plasma B-6 vitamer concentrations were determined in males aged 25-55 y who were long-term smokers, chewers, or nonusers. Tobacco users had either smoked (n = 23) or chewed (n = 11) for > 15 y; nonusers (n = 11) had never smoked or chewed. All subjects had normal hematocrit values. Food energy, protein, and vitamin B-6 intakes of the three groups of subjects were not significantly different. All subjects had fasting plasma pyridoxal-5'-phosphate (PLP) concentrations indicative of adequacy. Erythrocyte B-6 vitamer and 4-pyridoxic acid (4-PA) concentrations of all three groups were not significantly different. Nonusers had significantly higher plasma PLP concentrations than did smokers, whereas PLP concentrations of chewers were intermediate between the two groups. Chewers had significantly higher concentrations of plasma pyridoxamine-5'-phosphate (PMP) than other groups. Plasma pyridoxal, pyridoxine, pyridoxamine, and 4-PA concentrations of the three groups were not significantly different. Differences in some B-6 vitamer concentrations in plasma but not in erythrocytes were observed between tobacco users and nonusers.
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Eritrocitos/química , Plantas Tóxicas , Piridoxina/sangre , Fumar/sangre , Tabaco sin Humo , Adulto , Envejecimiento/fisiología , Estatura/fisiología , Peso Corporal/fisiología , Cromatografía Líquida de Alta Presión , Ingestión de Alimentos/fisiología , Hematócrito , Humanos , Masculino , Persona de Mediana Edad , Piridoxamina/análogos & derivados , Piridoxamina/sangre , Ácido Piridóxico/sangre , Piridoxina/administración & dosificación , Factores de TiempoRESUMEN
Novel synthetic polyene polyketones and new synthetic capsorubin isomers were examined for their ability to quench singlet molecular oxygen (1O2) generated by the thermodissociation of the endoperoxide of 3,3'-(1,4-naphthylene) dipropionate (NDPO2). C28-polyene-tetrone (1) exhibits the highest physical quenching rate constant with 1O2 (kq = 16 x 10(9) M-1 s-1). For comparison, the rate constant for the most efficient biological carotenoid, lycopene (3) is kq = 9 x 10(9) M-1 s-1 and that of beta-carotene (5) kq = 5 x 10(9) M-1 s-1. The presence of two oxalyl chromophores at the ends of the polyene chain seems to enhance the 1O2 quenching ability in the C28-polyene-tetrone (1). C28-polyene-tetrone-diacetal (2) (kq = 9 x 10(9) M-1 s-1) and C40-epiisocapsorubin (4) (kq = 8 x 10(9) M-1 s-1) also have high 1O2 quenching abilities. Two carotenoids from plants, phytoene and phytofluene, were much less efficient, kq values being below 10(7) M-1 s-1. Due to the very high singlet oxygen quenching abilities, C28-polyene-tetrone (1), C28-polyene-tetrone-diacetal (2) and C40-epiisocapsorubin (4) may have potential use in preventing 1O2-induced damage in biological and non-biological systems.
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Carotenoides/análogos & derivados , Carotenoides/química , Cetonas , Oxígeno , Isomerismo , Fotoquímica , Oxígeno Singlete , Relación Estructura-Actividad , XantófilasRESUMEN
Plasma carotenoid and tocopherol concentrations of men, aged 25 to 55 years, who were long-term chewers, smokers, or tobacco nonusers were determined. Tobacco users had either chewed (n = 11) or smoked (n = 23) for > 15 years. Nonusers (n = 10) had never smoked > 1 pack or chewed > 34 g. Food energy, mono- and poly-unsaturated and saturated fats, cholesterol, vitamin A, vitamin E, and carotenoid intakes of the three groups were not significantly different. Chewers and smokers reported consuming significantly less cryptoxanthin, found primarily in some fruits, and had significantly lower plasma cryptoxanthin levels than nonusers. Nonusers had significantly higher concentrations of plasma alpha-tocopherol than smokers; whereas those of chewers were intermediate. Nonusers had significantly higher concentrations of plasma gamma-tocopherol and total tocopherols than chewers or smokers. Plasma delta-tocopherol concentrations of the groups were not significantly different. Nonusers had significantly higher levels of beta-carotene than smokers but not chewers. Plasma lutein and lycopene concentrations of all groups were not significantly different. Dietary intakes of total carotenoids and tocopherols of the three groups were not significantly different, yet nonusers had higher plasma concentrations of total and most individual carotenoids and tocopherols than smokers with values for chewers being intermediate.
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Carotenoides/sangre , Plantas Tóxicas , Fumar/sangre , Tabaco sin Humo , Vitamina E/sangre , Adulto , Consumo de Bebidas Alcohólicas , Criptoxantinas , Hematócrito , Humanos , Luteína/sangre , Licopeno , Masculino , Persona de Mediana Edad , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Xantófilas , beta Caroteno/análogos & derivados , beta Caroteno/sangreRESUMEN
A juvenile raccoon (Procyon lotor) was found moribund near Fort Collins, Colorado (USA). Upon examination, the raccoon was dehydrated, had a mucopurulent oculonasal discharge and diarrhea, and was euthanized. Postmortem examination revealed emaciation, severe fibrinous gastroenteritis and a small, firm liver. Histopathological findings included blunting of villi, infiltration of lamina propria with neutrophils and plasma cells, and mild bronchopneumonia. Cryptosporidium sp. was demonstrated on intestinal villi and coronavirus and parvovirus were identified in feces. Fluorescent antibody test for rabies was negative and no evidence of canine distemper was found.
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Infecciones por Coronaviridae/veterinaria , Criptosporidiosis/complicaciones , Infecciones por Parvoviridae/veterinaria , Mapaches , Animales , Infecciones por Coronaviridae/complicaciones , Heces/microbiología , Gastroenteritis/complicaciones , Gastroenteritis/patología , Gastroenteritis/veterinaria , Intestinos/parasitología , Pulmón/patología , Microvellosidades/parasitología , Infecciones por Parvoviridae/complicaciones , Mapaches/parasitologíaRESUMEN
A female cockatiel had a 2-week history of abdominal distention, lethargy, and diarrhea. The cockatiel had a history of frequent egg-laying, and the owner suspected that she was egg-bound. A solid mass was removed through the cloaca and found to be a concretion of urates that had formed within a hernial pouch of the caudal abdominal musculature. Diagnosis was aided by contrast radiography, and surgery was performed. However, the abdominal hernias recurred 16 months later. The continual egg-laying probably predisposed this bird to hernia formation. Abdominal hernias in birds may be a consequence of continual egg-laying and associated hormonal effects leading to a weakening of abdominal musculature.
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Enfermedades de las Aves/diagnóstico por imagen , Cálculos/veterinaria , Hernia Ventral/veterinaria , Animales , Aves , Cálculos/diagnóstico por imagen , Femenino , Hernia Ventral/diagnóstico por imagen , Radiografía , Ácido Úrico/análisisRESUMEN
An adult 3,500-kg female African elephant was anesthetized 3 times for treatment of subcutaneous fistulas over the lateral aspect of each cubitus (anesthesia 1 and 2) and for repair of a fractured tusk (anesthesia 3). Lateral recumbency and anesthesia were achieved with etorphine (anesthesia 1 and 2) or etorphine and azaperone (anesthesia 3). The elephant's trachea was intubated and anesthesia was maintained by use of isoflurane and oxygen delivered via 2 standard large animal anesthesia machines joined in parallel. The range of total recumbency time was 2.4 to 3.3 hours. Breathing and heart rates, systemic arterial pressure, rectal temperature, PaO2, pH, and end-tidal gases were monitored. After administration of etorphine, measurements were made while the air-breathing elephant was recumbent, then every 5 minutes (cardiovascular) or 15 minutes (blood gases) after commencement of administration of isoflurane and oxygen. Tachycardia and hypertension were detected after administration of etorphine, but heart rate and systemic arterial pressure decreased to within normal ranges after administration of isoflurane and oxygen. The elephant remained well oxygenated while anesthetized and breathing a high oxygen mixture. The elephant had an uneventful recovery from each anesthesia.