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1.
Vet Radiol Ultrasound ; 65(3): 246-249, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38414109

RESUMO

A 13-year-old spayed female Persian cat presented with dyspnea and nasal discharge. Thoracic radiography revealed a dome-shaped soft-tissue opacity in the carina. Computed tomography confirmed a soft tissue-attenuating mass in the carina and the left and right proximal main bronchi that appeared to arise from the tracheal wall. Tracheoscopy revealed an intraluminal broad-based mass with multilobulated borders at the same location. Histopathological evaluation revealed a benign neoplastic process of the glandular epithelial lineage, which was considered an adenoma. Tracheal adenomas should be included in the differential diagnosis of tracheal masses.


Assuntos
Adenoma , Doenças do Gato , Tomografia Computadorizada por Raios X , Neoplasias da Traqueia , Animais , Gatos , Feminino , Doenças do Gato/diagnóstico por imagem , Doenças do Gato/patologia , Neoplasias da Traqueia/veterinária , Neoplasias da Traqueia/diagnóstico por imagem , Adenoma/veterinária , Adenoma/diagnóstico por imagem , Adenoma/patologia , Tomografia Computadorizada por Raios X/veterinária , Diagnóstico Diferencial , Traqueia/diagnóstico por imagem , Traqueia/patologia , Radiografia Torácica/veterinária
2.
Vet Radiol Ultrasound ; 64(1): 140-148, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36049077

RESUMO

The renal cortical thickness (RCT) has been correlated with renal function. Previous studies have also reported that the RCT:Abdominal aorta(Ao) ratio is constant in normal dogs with various physical factors. This multi-center, retrospective, analytical study aimed to determine if there are differences between actual RCT and predicted value of RCT considering physical factors in dogs with acute or chronic renal disease. We also aimed to demonstrate whether the RCT and Ao ratio index would be useful for evaluating renal pathology. A total of 54 dogs with acute or chronic renal disease and 30 normal healthy dogs were included in this study. The RCT was measured at the center of the renal pyramid as the shortest distance perpendicular to the renal capsule from the base of the renal medullary pyramid at three points. The diameter of the Ao was measured just caudal to the branch of the left renal artery in the sagittal plane in systole. The RCT:Ao ratio of chronic kidney disease (CKD) patients was 0.50 ± 0.11 (mean ± standard deviation). The RCT:Ao ratio in normal dogs was 0.67 ± 0.07. The RCT:Ao ratio in patients with acute kidney injury (AKI) was 0.83 ± 0.05. There was a statistically significant difference between normal dogs and dogs with CKD (P < 0.001) and between normal dogs and dogs with AKI (P < 0.001). In conclusion, findings from the current study supported using the RCT:Ao ratio as a non-invasive quantitative method for characterizing kidney pathology in dogs with acute or chronic renal disease.


Assuntos
Injúria Renal Aguda , Doenças do Cão , Insuficiência Renal Crônica , Cães , Animais , Insuficiência Renal Crônica/diagnóstico por imagem , Insuficiência Renal Crônica/veterinária , Rim/diagnóstico por imagem , Injúria Renal Aguda/veterinária , Aorta Abdominal/diagnóstico por imagem , Doenças do Cão/diagnóstico por imagem
3.
Circ Res ; 127(1): 91-110, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32716814

RESUMO

Atrial fibrillation (AF) is the most common sustained arrhythmia encountered in humans and is a significant source of morbidity and mortality. Despite its prevalence, our mechanistic understanding is incomplete, the therapeutic options have limited efficacy, and are often fraught with risks. A better biological understanding of AF is needed to spearhead novel therapeutic avenues. Although "natural" AF is nearly nonexistent in most species, animal models have contributed significantly to our understanding of AF and some therapeutic options. However, the impediments of animal models are also apparent and stem largely from the differences in basic physiology as well as the complexities underlying human AF; these preclude the creation of a "perfect" animal model and have obviated the translation of animal findings. Herein, we review the vast array of AF models available, spanning the mouse heart (weighing 1/1000th of a human heart) to the horse heart (10× heavier than the human heart). We attempt to highlight the features of each model that bring value to our understanding of AF but also the shortcomings and pitfalls. Finally, we borrowed the concept of a SWOT analysis from the business community (which stands for strengths, weaknesses, opportunities, and threats) and applied this introspective type of analysis to animal models for AF. We identify unmet needs and stress that is in the context of rapidly advancing technologies, these present opportunities for the future use of animal models.


Assuntos
Fibrilação Atrial/fisiopatologia , Modelos Animais de Doenças , Animais , Animais de Laboratório/anatomia & histologia , Animais de Laboratório/fisiologia , Fibrilação Atrial/etiologia , Fibrilação Atrial/patologia , Humanos , Especificidade da Espécie
4.
Vet Radiol Ultrasound ; 63(2): e1-e4, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34637579

RESUMO

A 9-year-old dog was presented with hematuria and urinary incontinence. Ultrasonography revealed multiple mobile echogenic ball-shaped structures without distal acoustic shadowing within the lumen. A cystocentesis was performed and a urinalysis of the urine revealed fungus. Candida albicans was identified using an additional urine culture. The patient was finally diagnosed with fungal cystitis with mobile fungal balls and managed with Itraconazole. Follow-up ultrasonography demonstrated the resolution of cystitis without fungal balls. Our findings suggest that fungal balls should be considered as a differential diagnosis when echogenic mobile ball-shaped structures are identified in the urinary bladder of a diabetic or immunocompromised patient.


Assuntos
Candidíase , Cistite , Doenças do Cão , Animais , Candidíase/diagnóstico por imagem , Candidíase/microbiologia , Candidíase/veterinária , Cistite/diagnóstico por imagem , Cistite/veterinária , Doenças do Cão/diagnóstico por imagem , Cães , Pelve , Ultrassonografia/veterinária , Bexiga Urinária/diagnóstico por imagem
5.
Vet Radiol Ultrasound ; 63(3): 337-344, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35023240

RESUMO

The renal cortical thickness (RCT) reflects the pathological condition of the kidney, and measuring this parameter can help diagnose renal fibrosis in dogs. The normal reference range of RCT in dogs is broad (3-8 mm) because of the extreme diversity in body size. Therefore, this retrospective, reference interval, and observational design study aimed to establish a normal reference range for RCT in dogs measured using ultrasound by considering bodyweight (BW), body surface area (BSA), body condition score (BCS), and abdominal aorta (Ao) diameter. A total of 60 dogs met the inclusion criteria, and abdominal ultrasound images and medical records of these dogs were analyzed. RCT was measured at 1-3 points where the renal capsule and broad base of the medullary pyramid were clearly observed. Ao diameter was measured caudal to the branch of the left renal artery in the mid-sagittal view. The RCT showed positive correlations with BW and BSA and a negative correlation with BCS, which can be described as follows: RCT (mm) = 0.131 × BW - 0.166 × BCS + 3.580. The RCT:Ao ratio was 0.70 ± 0.09 (mean ± standard deviation). No significant differences were found in the RCT:Ao ratio depending on BW or BCS. In conclusion, the RCT:Ao ratio and relative RCT considering both BW and BCS are potentially useful for evaluating the normality of the renal cortex on ultrasound examination in dogs with various physiques.


Assuntos
Aorta Abdominal , Rim , Animais , Aorta Abdominal/diagnóstico por imagem , Peso Corporal , Cães , Rim/diagnóstico por imagem , Valores de Referência , Estudos Retrospectivos , Ultrassonografia/veterinária
6.
Microcirculation ; 28(6): e12701, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33866635

RESUMO

This study was designed to identify the effects of a 12-h nicotine patch administration on cold induced vasodilation (CIVD) in healthy young chronic smokers following 16 h of abstinence from smoking. Two laser Doppler probes and temperature thermocouples were placed on the dorsal part of the distal phalanx of the middle and ring fingers of 7 smokers (>12 cigarettes/day). Following 16 h of abstinence from smoking, smokers were tested with and without administration of a 21 mg transdermal nicotine patch (NicoDerm® ). Each participant's right hand was immersed in cold (~5°C) water for 40 min. Cutaneous vascular conductance (CVC) was calculated from non-invasive arterial finger blood pressure and skin blood flow and expressed as a percentage of peak CVC observed during hand skin heating to 44°C. For comparison purposes, the CIVD response of a non-smoking cohort without nicotine patch (n = 10) was also examined. Baseline CVC was similar in smokers and non-smokers (27.8 ± 12.6 CVC % peak). The initial vasoconstriction during cold-water immersion decreased skin blood flow to 4.0 ± 3.9 CVC % peak in both smokers and non-smokers. The onset of CIVD in smokers (4.5 ± 1.5 min) was delayed compared to non-smoker (3.3 ± 0.8 min, p < .05). The area under the CVC %peak-time curve during cold-water immersion averaged 1250 ± 388 CVC %peak · min in non-smokers which was larger (p < .05) than smokers with or without nicotine (789 ± 542 and 862 ± 517 CVC %peak · min, respectively). Chronic smoking impaired the CIVD response to cold-water immersion of the hand; however, the impaired CIVD response in 16 h of abstinence from smoking was not influenced by application of a 21 mg transdermal nicotine patch.


Assuntos
Fumantes , Vasodilatação , Humanos , Temperatura Cutânea , Dispositivos para o Abandono do Uso de Tabaco , Água
7.
J Cardiovasc Electrophysiol ; 32(5): 1281-1289, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33625757

RESUMO

INTRODUCTION: We previously introduced the inverse solution guidance algorithm (ISGA) methodology using a Single Equivalent Moving Dipole model of cardiac electrical activity to localize both the exit site of a re-entrant circuit and the tip of a radiofrequency (RF) ablation catheter. The purpose of this study was to investigate the use of ISGA for ablation catheter guidance in an animal model. METHODS: Ventricular tachycardia (VT) was simulated by rapid ventricular pacing at a target site in eleven Yorkshire swine. The ablation target was established using three different techniques: a pacing lead placed into the ventricular wall at the mid-myocardial level (Type-1), an intracardiac mapping catheter (Type-2), and an RF ablation catheter placed at a random position on the endocardial surface (Type-3). In each experiment, one operator placed the catheter/pacing lead at the target location, while another used the ISGA system to manipulate the RF ablation catheter starting from a random ventricular location to locate the target. RESULTS: The average localization error of the RF ablation catheter tip was 0.31 ± 0.08 cm. After analyzing approximately 35 cardiac cycles of simulated VT, the ISGA system's accuracy in locating the target was 0.4 cm after four catheter movements in the Type-1 experiment, 0.48 cm after six movements in the Type-2 experiment, and 0.67 cm after seven movements in the Type-3 experiment. CONCLUSION: We demonstrated the feasibility of using the ISGA method to guide an ablation catheter to the origin of a VT focus by analyzing a few beats of body surface potentials without electro-anatomic mapping.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Algoritmos , Animais , Catéteres , Coração , Suínos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/cirurgia
8.
J Clin Monit Comput ; 34(2): 261-270, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31104305

RESUMO

In this study, new and existing methods of estimating stroke volume, cardiac output and total peripheral resistance from analysis of the arterial blood pressure waveform were tested over a wide range of conditions. These pulse contour analysis methods (PCMs) were applied to data obtained in six swine during infusion of volume, phenylephrine, dobutamine, isoproterenol, esmolol and nitroglycerine as well as during progressive hemorrhage. Performance of PCMs was compared using true end-ejection pressures as well as estimated end-ejection pressures. There was considerable overlap in the accuracies of the PCMs when using true end-ejection measures. However, for perhaps the most clinically relevant condition, where radial artery pressure is the input, only Wesseling's Corrected Impedance method and the Kouchoukos Correction method achieved statistically superior results. We introduced a method of estimating end-ejection by determining when the systolic pressure dropped to a value equal to the sum of the end-diastolic pressure plus a fraction of the pulse pressure. The most accurate estimation of end-ejection was obtained when that fraction was set to 60% for the central arterial pressure and to 50% for the femoral and radial arterial pressures. When the estimated end-ejection measures were used for the PCMs that depend on end-ejection measures and when radial artery pressure was used as the input, only Wesseling's Corrected Impedance method and the modified Herd's method achieved statistically superior results. This study provides a systematic comparison of multiple PCMs' ability to estimate stroke volume, cardiac output, and total peripheral resistance and introduces a new method of estimating end-systole.


Assuntos
Monitorização Hemodinâmica/veterinária , Sus scrofa/fisiologia , Algoritmos , Animais , Pressão Arterial , Pressão Sanguínea , Débito Cardíaco , Monitorização Hemodinâmica/métodos , Monitorização Hemodinâmica/estatística & dados numéricos , Humanos , Modelos Cardiovasculares , Análise de Onda de Pulso , Volume Sistólico , Resistência Vascular
9.
Molecules ; 24(2)2019 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-30658439

RESUMO

Chrysanthemum morifolium Ramat is a perennial flowering plant widely cultivated for use in a tea infusion and as a popular beverage. To identify and evaluate the tea infusion made with a γ-irradiated mutant chrysanthemum cultivar with dark purple petals (cv. ARTI-Dark Chocolate), its phytochemical composition and antioxidant activity were tested and compared with those of the commercially available chrysanthemum cultivar with yellow petals (cv. Gamguk) by HPLC-DAD-ESIMS, as well as DPPH and ABTS radical scavenging assays. The purple chrysanthemum tea contained anthocyanins and linarin, which were not detected in the yellow chrysanthemum tea and the content of chlorogenic acid, acacetin-7-O-ß-glucoside, and luteolin was higher compared with the yellow chrysanthemum tea. In contrast, the yellow chrysanthemum tea had higher luteolin-7-O-ß-glucoside, 3,5-dicaffeoylquinic acid, apigenin-7-O-ß-glucoside, and apigenin contents in comparison with the purple chrysanthemum tea. In addition, the content and antioxidant activity of the two chrysanthemum teas were investigated according to different water temperatures and infusing time. The yellow chrysanthemum tea did not show any significant differences according to infusing time and temperature, while the purple chrysanthemum tea was more influenced by the infusing time than water temperature, showing the highest total compound content in the infusing condition of 100 °C and 4 min. Moreover, the floral scent volatiles of the two chrysanthemum tea sources were analyzed using HS-SPME-GC-MS. In the DPPH radical scavenging assay, the purple chrysanthemum tea broadly showed greater antioxidant activity than did the yellow chrysanthemum tea, corresponding to the high content of anthocyanins known as the powerful antioxidant. Further, both chrysanthemum flower teas exhibited strong ABTS radical scavenging effects ranging from 76% to 61% under all infusing conditions. Therefore, the purple chrysanthemum cultivar, ARTI-Dark Chocolate, is worthy of breeding as a new tea cultivar.


Assuntos
Antioxidantes/farmacologia , Bebidas/análise , Chrysanthemum/química , Flores/química , Compostos Fitoquímicos/análise , Pigmentação , Antocianinas/análise , Calibragem , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Limite de Detecção , Odorantes/análise , Fenóis/análise , Compostos Fitoquímicos/química , Padrões de Referência , Compostos Orgânicos Voláteis/análise
10.
J Sci Food Agric ; 99(1): 290-301, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29862514

RESUMO

BACKGROUND: Ultrasonication, agitation and stirring or a combination of ultrasonication, agitation and stirring extraction techniques were applied to observe their effects on the physicochemical properties, health-promoting phytochemicals, and structure of cold brewed coffee. RESULTS: All the extraction techniques led to significant (P < 0.05) increases in the color values, total soluble solids, antioxidant activities and most organic acids, while a combination of extraction techniques increased the chlorogenic acid and caffeine content significantly (P < 0.05) compared with that by conventional methods. Fourier transform infrared spectroscopy allowed us to identify the different compounds in the cold-brewed coffee extract rapidly. The partial least square regression model presented good predictability because experimental and predicted values were close to each other. Principal component analysis revealed that levels of all phytochemicals correlated with the use of non-conventional methods. CONCLUSION: The combination of ultrasonication and agitation might be the best option to enhance the various phytochemicals in cold-brewed coffee. © 2018 Society of Chemical Industry.


Assuntos
Café/química , Culinária/métodos , Compostos Fitoquímicos/isolamento & purificação , Sementes/química , Cafeína/análise , Cafeína/isolamento & purificação , Ácido Clorogênico/análise , Ácido Clorogênico/isolamento & purificação , Cor , Compostos Fitoquímicos/química , Ultrassom/métodos
11.
J Food Sci Technol ; 56(6): 2836-2844, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31205339

RESUMO

The bioaccessibility, antioxidant activity, and bioactive and volatile compounds of freeze-dried Asian pear powder (FDAPP) and hot air-dried Asian pear powder (HDAPP) were investigated. Compared to FDAPP, HDAPP exhibited significantly (p < 0.05) higher total phenolic, arbutin, and bioaccessible phenolic contents and the ferric reducing ability of plasma for the free phenolic fraction. However, all antioxidant activities for the bound phenolic fraction were lower in HDAPP, which could contribute to the release of bound antioxidant components due to cell rupture in the HDAPP. Based on the volatile profile, hot air drying provided a sweet as well as attractive flavor in the Asian pear powder (APP). Considering economic viability, higher levels of bioactive compounds, and desirable aromatic properties, hot air drying is the better option compared to freeze-drying for APP production, which could be used as a functional ingredient in food products.

12.
Vet Radiol Ultrasound ; 59(5): 564-570, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29931791

RESUMO

Bronchoalveolar lavage is a common diagnostic test for dogs with suspected pulmonary disease, however there is no published information on whether this procedure could affect the imaging characteristics of the lungs. Aims of this prospective experimental study were to describe computed tomography (CT) and radiographic features of the lungs after bronchoalveolar lavage in a sample of healthy dogs. Thoracic CT and radiographic images of eight healthy Beagles were acquired at the following time points: before bronchoalveolar lavage, immediately following bronchoalveolar lavage, and at 2, 4, 8, 12, and 24 h following bronchoalveolar lavage. Lung consolidation or interstitial patterns were seen in CT and radiographic images immediately after the procedure. Radiographic lung patterns resolved within 2 h and CT patterns resolved within 24 h. Resolution of the CT pulmonary patterns in the ventral areas of the lungs was delayed compared to the dorsal areas. Mean CT imaging scores differed over time (P < 0.001), while mean radiographic imaging scores did not differ over time. This study suggests that thoracic radiography and CT imaging assessments should precede bronchoalveolar lavage procedures if possible, or be performed at least 24 h afterward.


Assuntos
Lavagem Broncoalveolar/veterinária , Pulmão/diagnóstico por imagem , Radiografia Torácica/veterinária , Tomografia Computadorizada por Raios X/veterinária , Animais , Cães/anormalidades , Feminino , Pulmão/anormalidades , Masculino , Estudos Prospectivos , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos
13.
Vet Radiol Ultrasound ; 57(6): E67-E70, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27252093

RESUMO

A 9-year-old intact female mixed breed dog was presented for mammary gland tumor surgery, and preoperative radiographs showed a tubular soft tissue opacity mass with multifocal mineralization in the caudoventral abdominal cavity. Subsequent ultrasonography demonstrated uterine dilation with echogenic fluid and endometrial acoustic shadowing consistent with mineralization. Resection of mammary gland tumors and ovariohysterectomy were performed. Pyometra was diagnosed on cytologic examination of uterine fluid. Histopathology of the uterine tissue confirmed a diagnosis of cystic endometrial hyperplasia with uterine mineralization.


Assuntos
Doenças do Cão/diagnóstico por imagem , Piometra/veterinária , Animais , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Cães , Hiperplasia Endometrial/diagnóstico , Hiperplasia Endometrial/patologia , Hiperplasia Endometrial/cirurgia , Hiperplasia Endometrial/veterinária , Feminino , Histerectomia/veterinária , Ovariectomia/veterinária , Piometra/diagnóstico por imagem
14.
Pacing Clin Electrophysiol ; 37(8): 1038-50, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24645803

RESUMO

BACKGROUND: We have introduced a method to guide radiofrequency catheter ablation (RCA) procedures that estimates the location of a catheter tip used to pace the ventricles and the target site for ablation using the single equivalent moving dipole (SEMD). OBJECTIVE: To investigate the accuracy of this method in resolving epicardial and endocardial electrical sources. METHODS: Two electrode arrays, each of nine pacing electrodes at known distances from each other, sutured on the left- and right-ventricular (LV and RV) epicardial surfaces of swine, were used to pace the heart at multiple rates, while body surface potentials from 64 sites were recorded and used to estimate the SEMD location. A similar approach was followed for pacing from catheters in the LV and RV. RESULTS: The overall (RV & LV) error in estimating the interelectrode distance of adjacent epicardial electrodes was 0.38 ± 0.45 cm. The overall endocardial (RV & LV) interelectrode distance error, was 0.44 ± 0.26 cm. Heart rate did not significantly affect the error of the estimated SEMD location (P > 0.05). The guiding process error became progressively smaller as the SEMD approached an epicardial target site and close to the target, the overall absolute error was ∼ 0.28 cm. The estimated epicardial SEMD locations preserved their topology in image space with respect to their corresponding physical location of the epicardial electrodes. CONCLUSION: The proposed algorithm suggests one can efficiently and accurately resolve epicardial electrical sources without the need of an imaging modality. In addition, the error in resolving these sources is sufficient to guide RCA procedures.


Assuntos
Algoritmos , Fontes de Energia Bioelétrica , Ablação por Cateter/métodos , Animais , Fenômenos Eletrofisiológicos , Suínos
15.
J Nanosci Nanotechnol ; 14(11): 8279-87, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25958515

RESUMO

Narrowly dispersed poly(BMA-co-MMA) and PBMA latices with particle diameters ranging within 216-435 nm were synthesized successfully by surfactant-free emulsion polymerization with KPS and AIBA. The average particle diameter and particle size distribution, average molecular weight and its distribution, glass transition temperature, reflectance spectra in visible wavelength, and refractive indices for the respective poly(BMA-co-MMA) latices and their photonic crystals were systematically investigated in terms of BMA/MMA ratio, BMA content, polymerization temperature, and DVB effect. The rate of polymerization increased with increasing MMA concentration in BMA/MMA ratio. The particle diameter increased with BMA concentration in BMA/MMA ratio. The molecular weight increased with BMA concentration in BMA/MMA ratio and monomer concentration. The drying of the latices offered self-assembled shiny colloidal crystal films showing the characteristic structural colors in visible wavelength. All the poly(BMA-co-MMA) latices prepared in the study were fallen within the range of photonic grade microspheres. The reflectance measurement on the colloidal photonic crystals having different particle diameters clearly exhibited narrow stopbands. The reflection maxima (λ(max)) measured in this study were well close to the λ(max) calculated, derived from the Bragg's equation. The refractive indices of poly(BMA-co-MMA) photonic crystals were found to be almost same as the theoretical values and increased proportionally from 1.50 to 1.57 with BMA content in BMA/MMA ratios. It was, thus, found that the optical reflectance properties of the poly(BMA-co-MMA) colloidal photonic crystals can be controlled easily by adjusting the reaction conditions and BMA/MMA ratio in soap-free emulsion copolymerization of BMA and MMA.


Assuntos
Metacrilatos/química , Metilmetacrilatos/química , Microesferas , Ácidos Polimetacrílicos/química , Emulsões/química , Peso Molecular , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia , Óptica e Fotônica , Tamanho da Partícula , Polimerização , Refratometria
16.
Front Vet Sci ; 11: 1334438, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38425836

RESUMO

Introduction: Spondylosis deformans is a non-inflammatory osteophytic reaction that develops to re-establish the stability of weakened joints between intervertebral discs. However, assessing these changes using radiography is subjective and difficult. In human medicine, attempts have been made to use artificial intelligence to accurately diagnose difficult and ambiguous diseases in medical imaging. Deep learning, a form of artificial intelligence, is most commonly used in medical imaging data analysis. It is a technique that utilizes neural networks to self-learn and extract features from data to diagnose diseases. However, no deep learning model has been developed to detect vertebral diseases in canine thoracolumbar and lumbar lateral X-ray images. Therefore, this study aimed to establish a segmentation model that automatically recognizes the vertebral body and spondylosis deformans in the thoracolumbar and lumbar lateral radiographs of dogs. Methods: A total of 265 thoracolumbar and lumbar lateral radiographic images from 162 dogs were used to develop and evaluate the deep learning model based on the attention U-Net algorithm to segment the vertebral body and detect spondylosis deformans. Results: When comparing the ability of the deep learning model and veterinary clinicians to recognize spondylosis deformans in the test dataset, the kappa value was 0.839, indicating an almost perfect agreement. Conclusions: The deep learning model developed in this study is expected to automatically detect spondylosis deformans on thoracolumbar and lumbar lateral radiographs of dogs, helping to quickly and accurately identify unstable intervertebral disc space sites. Furthermore, the segmentation model developed in this study is expected to be useful for developing models that automatically recognize various vertebral and disc diseases.

17.
Front Vet Sci ; 11: 1394896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895712

RESUMO

Introduction: The effects of pre-anesthetic single-dose oral pimobendan during inhalational anesthesia, including the comparison with the effects of single intravenous pimobendan under anesthesia, remain unexplored. Therefore, this study aimed to determine changes in hemodynamic and echocardiographic parameters induced by pre-anesthetic administration of oral pimobendan under isoflurane general anesthesia and to compare them with those induced by intravenous pimobendan. Methods: Thirteen clinically normal dogs (4 laboratory and 9 client-owned dogs) with no clinical signs and not on any medical treatment were included. Anesthesia was performed three times: no pimobendan (Control), oral pimobendan (PIMO PO, 0.3 mg/kg), and intravenous pimobendan (PIMO IV, 0.15 mg/kg). Echocardiographic and hemodynamic parameters were monitored at 30-min intervals in all groups. Results: Compared to the Control group, end-systolic volume index (ESVI) and normalized left ventricular internal diameter at end-systole (LVIDSN) were significantly lower, and fractional shortening (FS) and ejection fraction (EF) were significantly higher in the PIMO PO and IV groups (p < 0.001). Global radial strain (GRS) was significantly higher in the PIMO PO and IV groups (p = 0.015). Conclusion: Under general anesthesia, oral pimobendan preserved LV systolic and myocardial function in a manner comparable to intravenous pimobendan. Pre-anesthetic administration of oral pimobendan can be used to compensate for cardiac systolic function in dogs who require therapeutic and diagnostic procedures under general anesthesia with potential risk of circulatory failure.

18.
Front Vet Sci ; 11: 1400076, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840636

RESUMO

Introduction: Studies on aberrant bronchoesophageal arteries are limited. Herein, we report a case of a multi-origin systemic-to-pulmonary shunt with suspected bronchoesophageal artery hypertrophy and fistula in a dog. Case report: A 4-year-old castrated male beagle weighing 11 kg underwent routine medical screening. Physical examination revealed a right-sided continuous murmur of grades 1-2. Thoracic radiography revealed a mild cardiomegaly. Echocardiography revealed a continuous turbulent shunt flow distal to the right pulmonary artery (RPA) branch from the right parasternal short axis pulmonary artery view. Computed tomography demonstrated systemic-to-pulmonary shunts originating from the descending aorta at the level of T7-8, the right 5th and 6th dorsal intercostal arteries, and the right brachiocephalic trunk, which formed anomalous networks around the trachea and esophagus that anastomosed into a large tortuous vessel at the level of T6-7 and entered the RPA. Surgical ligation of multiple shunting vessels was performed. Postoperative echocardiography and computed tomography showed decreased left ventricular volume overload and markedly decreased size of the varices. Additionally, most of the shunting vessels were without residual shunt flow. Conclusion: The present study provides information regarding imaging features and the successful surgical management of multiple systemic-to-pulmonary shunts originating from the descending aorta, right brachiocephalic trunk, and intercostal arteries and terminating at the RPA. Multimodal imaging features after surgical ligation have also been described.

19.
Pacing Clin Electrophysiol ; 36(7): 811-22, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23448231

RESUMO

BACKGROUND: We developed and evaluated a novel system for guiding radiofrequency catheter ablation therapy of ventricular tachycardia. This guidance system employs an inverse solution guidance algorithm (ISGA) using a single equivalent moving dipole (SEMD) localization method. The method and system were evaluated in both a saline tank phantom model and in vivo animal (swine) experiments. METHODS: A catheter with two platinum electrodes spaced 3 mm apart was used as the dipole source in the phantom study. A 40-Hz sinusoidal signal was applied to the electrode pair. In the animal study, four to eight electrodes were sutured onto the right ventricle. These electrodes were connected to a stimulus generator delivering 1-ms duration pacing pulses. Signals were recorded from 64 electrodes, located either on the inner surface of the saline tank or on the body surface of the pig, and then processed by the ISGA to localize the physical or bioelectrical SEMD. RESULTS: In the phantom studies, the guidance algorithm was used to advance a catheter tip to the location of the source dipole. The distance from the final position of the catheter tip to the position of the target dipole was 2.22 ± 0.78 mm in real space and 1.38 ± 0.78 mm in image space (computational space). The ISGA successfully tracked the locations of electrodes sutured on the ventricular myocardium and the movement of an endocardial catheter placed in the animal's right ventricle. CONCLUSION: In conclusion, we successfully demonstrated the feasibility of using an SEMD inverse algorithm to guide a cardiac ablation catheter.


Assuntos
Algoritmos , Mapeamento Potencial de Superfície Corporal/métodos , Ablação por Cateter/métodos , Sistema de Condução Cardíaco/fisiologia , Sistema de Condução Cardíaco/cirurgia , Modelos Cardiovasculares , Cirurgia Assistida por Computador/métodos , Animais , Mapeamento Potencial de Superfície Corporal/instrumentação , Simulação por Computador , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Cirurgia Assistida por Computador/instrumentação , Suínos
20.
Clin Auton Res ; 23(3): 123-31, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23467970

RESUMO

OBJECTIVE: Post-reperfusion syndrome (PRS), severe hypotension after graft reperfusion during liver transplantation, is an adverse clinical event associated with poorer patient outcomes. The purpose of this study was to determine whether alterations in autonomic control in liver transplant recipients prior to graft reperfusion are associated with the subsequent development of PRS. METHODS: Heart rate variability (HRV), systolic arterial blood pressure (SBP) variability, and baroreflex sensitivity of 218 liver transplant recipients were evaluated using 5 min of ECG and arterial blood pressure signals 10 min before graft reperfusion along with other clinical parameters. Logistic regression analyses were performed to assess predictors of PRS occurrence. RESULTS: Seventy-seven patients (35 %) developed PRS while 141 did not. There were significant differences in SBP (110 ± 16 vs. 119 ± 16 mmHg, P < 0.001) and the ratio of low frequency power to high frequency power (LF/HF) of HRV (1.0 ± 1.4 vs. 2.1 ± 3.7, P = 0.003) between the PRS group and No-PRS group. In multivariate logistic regression analysis, predictors were LF/HF (odds ratio 0.817, P = 0.028) and SBP (odds ratio 0.966, P < 0.001). INTERPRETATION: Low LF/HF and SBP measured before hepatic graft reperfusion were significantly correlated with subsequent PRS occurrence, suggesting that sympathovagal imbalance and depressed SBP may be key factors predisposing to reperfusion-related severe hypotension in liver transplant recipients.


Assuntos
Hipotensão/etiologia , Hipotensão/fisiopatologia , Transplante de Fígado/efeitos adversos , Fígado/irrigação sanguínea , Sistema Nervoso Simpático/fisiopatologia , Pressão Sanguínea/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
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