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1.
Vet Radiol Ultrasound ; 65(3): 187-192, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38349181

RESUMO

Compressive hydrated nucleus pulposus extrusion (HNPE) is a sudden extrusion of hydrated, nondegenerated nucleus pulposus material with well-known characteristic MRI findings. The appearance of compressive HNPE during contrast-enhanced CT has already been described, but never its myelo-CT characteristics. The aim of this retrospective multicenter case series is to describe the myelo-CT findings in 15 dogs with compressive HNPE confirmed with gross surgical findings. A distinctive and consistent myelo-CT appearance of cervical compressive HNPE in dogs that included a focal extradural "seagull"-shaped extradural compression dorsal to the annulus fibrosus combined with a narrowing of the affected intervertebral disc space was found. The extruded material was hypoattenuating in the soft tissue algorithm. Myelo-CT could be a useful diagnostic tool and influence the clinical decision to address cervical compressive HNPE conservatively or surgically when MRI is not available.


Assuntos
Vértebras Cervicais , Doenças do Cão , Deslocamento do Disco Intervertebral , Núcleo Pulposo , Tomografia Computadorizada por Raios X , Animais , Cães , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/cirurgia , Núcleo Pulposo/diagnóstico por imagem , Estudos Retrospectivos , Deslocamento do Disco Intervertebral/veterinária , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/cirurgia , Feminino , Masculino , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Tomografia Computadorizada por Raios X/veterinária , Mielografia/veterinária , Imageamento por Ressonância Magnética/veterinária
2.
Appl Opt ; 61(28): 8540-8552, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256172

RESUMO

We report here the first implementation of chemically specific imaging in the exhaust plume of a gas turbine typical of those used for propulsion in commercial aircraft. The method used is chemical species tomography (CST) and the target species is CO2, absorbing in the near-infrared at 1999.4 nm. A total of 126 beams propagate transverse to the plume axis, along 7 m paths in a coplanar geometry, to probe a central region of diameter ≈1.5m. The CO2 absorption spectrum is measured using tunable diode laser spectroscopy with wavelength modulation, using the second harmonic to first harmonic (2f/1f) ratio method. The engine is operated over the full range of thrust, while data are recorded in a quasi-simultaneous mode at frame rates of 1.25 and 0.3125 Hz. Various data inversion methodologies are considered and presented for image reconstruction. At all thrust levels a persistent ring structure of high CO2 concentration is observed in the central region of the measurement plane, with a raised region in the middle of the plume assumed to be due to the engine's boat tail. With its potential to target various exhaust species, the CST method outlined here offers a new approach to turbine combustion research, turbine engine development, and aviation fuel research and development.

3.
J Vet Med Educ ; 46(4): 523-532, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30418815

RESUMO

Vertebral fractures and luxations are common causes of neurological emergencies in small-animal patients. The objective of this study was to evaluate the impact of three-dimensional printing (3Dp) models on how veterinary students understand and learn to identify canine spinal fractures and to compare 3Dp models to computed tomography (CT) images and three-dimensional CT (3D-CT) reconstructions. Three spinal fracture models were generated by 3Dp. Sixty first-year veterinary students were randomized into three teaching module groups (CT, 3D-CT, or 3Dp) and asked to answer a multiple-choice questionnaire with 12 questions that covered normal spinal anatomy and the identification of vertebral fractures. We used four additional questions to evaluate the overall learning experience and knowledge acquisition. Results showed that students in the 3Dp group performed significantly better than those in the CT (p < .001) and the 3D-CT (p < .001) groups. Students in the 3Dp and 3D-CT groups answered all questions more quickly than the CT group (3Dp versus CT, p < .001; 3D-CTversus CT, p < .001), with no significant differences between the 3Dp and 3D-CT groups (p = .051). Only the degree of knowledge acquisition that the students considered they had acquired during the session showed significant differences between groups (p = .01). In conclusion, across first-year veterinary students, 3Dp models facilitated learning about normal canine vertebral anatomy and markedly improved the identification of canine spinal fractures. Three-dimensional printing models are an easy and inexpensive teaching method that could be incorporated into veterinary neuroanatomy classes to improve learning in undergraduate students.


Assuntos
Educação em Veterinária , Impressão Tridimensional , Fraturas da Coluna Vertebral , Animais , Cães , Educação em Veterinária/métodos , Avaliação Educacional , Humanos , Imageamento Tridimensional/veterinária , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/veterinária
5.
Oncologist ; 19(9): 917-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25142843

RESUMO

BACKGROUND: The combination of gemcitabine plus capecitabine and sunitinib (GCS) shows activity in metastatic renal cell carcinoma (mRCC). We tested the multitargeted "chemo-switch" regimen as first-line treatment in patients with mRCC. METHODS: We assessed the maximum tolerated dose and antitumor activity of GCS in treatment-naïve, advanced mRCC patients. Treatment consisted of intravenous gemcitabine on days 1 and 8, oral capecitabine twice daily on days 1-14, and oral sunitinib daily for six 21-day cycles, followed by sunitinib monotherapy at the investigator's discretion. Dose level 0 (DL0) was gemcitabine 1,000 mg/m(2) per day plus capecitabine 650 mg/m(2) per 12 hours plus sunitinib 37.5 mg/day; DL1 was gemcitabine 1,000 mg/m(2) per day plus capecitabine 850 mg/m(2) per 12 hours plus sunitinib 37.5 mg/day. RESULTS: Sixteen patients were enrolled. At DL1, two of four patients had dose-limiting toxicity (DLT; grade 3 diarrhea and grade 4 thrombocytopenia). The dose was reduced to DL0 when only 1 of 12 patients experienced DLT (grade 3 diarrhea, grade 3 mucositis, and grade 3 thrombocytopenia). Dose reductions were frequent (58% of patients), and only seven patients were able to receive the three drugs for more than three cycles. One patient achieved a complete response, three had partial responses, and the best response for four was stable disease. CONCLUSION: The safety profile of the combination does not seem manageable in this patient population. No further development of the combination is recommended.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Indóis/administração & dosagem , Pirróis/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina , Carcinoma de Células Renais/patologia , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Relação Dose-Resposta a Droga , Esquema de Medicação , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Indóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Pirróis/efeitos adversos , Sunitinibe , Resultado do Tratamento , Gencitabina
6.
Opt Express ; 20(28): 29769-75, 2012 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-23388804

RESUMO

The low-cost in-home distribution of full-standard digital TV jointly with high-bitrate data using 50 m long 1 mm core diameter graded-index plastic optical fiber (GI-POF) is proposed and experimentally demonstrated. Discrete multitone (DMT) modulation is demonstrated to provide an adaptive bitrate which can spectrally coexist with digital video broadcasting-terrestrial (DVB-T) signals in 470-862 MHz. A 3 Gb/s DMT signal and two DVB-T channels are generated, transmitted and received exhibiting excellent performance.

7.
Br J Nutr ; 107(6): 834-44, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21806854

RESUMO

Here we examined the use of stable isotopes, [¹³C]starch and [¹5N]protein, as dietary tracers to study carbohydrate assimilation and distribution and protein utilisation, respectively, by rainbow trout (Oncorhynchus mykiss). The capacity of glucose uptake and use by tissues was studied, first, by varying the digestibility of carbohydrate-rich diets (30 % carbohydrate), using raw starch and gelatinised starch (GS) and, second, by observing the effects of two regimens of activity (voluntary swimming, control; sustained swimming at 1·3 body lengths/s, exercise) on the GS diet. Isotopic ratio enrichment (¹³C and ¹5N) of the various tissue components (protein, lipid and glycogen) was measured in the liver, muscles, viscera and the rest of the fish at 11 and 24 h after a forced meal. A level of 30 % of digestible carbohydrates in the food exceeded the capacity of rainbow trout to use this nutrient, causing long-lasting hyperglycaemia that raises glucose uptake by tissues, and the synthesis of glycogen and lipid in liver. Total 13C recovered 24 h post-feeding in the GS group was lower than at 11 h, indicating a proportional increase in glucose oxidation, although the deposition of lipids in white muscle (WM) increased. Prolonged hyperglycaemia was prevented by exercise, since sustained swimming enhances the use of dietary carbohydrates, mainly through conversion to lipids in liver and oxidation in muscles, especially in red muscle (RM). Higher recoveries of total 15N for exercised fish at 24 h, mainly into the protein fraction of both RM and WM, provide evidence that sustained swimming improves protein deposition, resulting in an enhancement of the protein-sparing effect.


Assuntos
Comportamento Animal , Dieta/veterinária , Proteínas de Peixes/metabolismo , Oncorhynchus mykiss/metabolismo , Amido/metabolismo , Natação , Animais , Metabolismo dos Carboidratos , Carboidratos/química , Isótopos de Carbono , Dieta/efeitos adversos , Digestão , Proteínas de Peixes/biossíntese , Géis , Hiperglicemia/etiologia , Hiperglicemia/prevenção & controle , Hiperglicemia/veterinária , Metabolismo dos Lipídeos , Fígado/metabolismo , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Lenta/metabolismo , Isótopos de Nitrogênio , Oncorhynchus mykiss/sangue , Oncorhynchus mykiss/crescimento & desenvolvimento , Amido/administração & dosagem , Amido/efeitos adversos , Amido/química , Triticum/metabolismo , Vísceras/metabolismo
8.
Opt Express ; 19(26): B895-904, 2011 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-22274117

RESUMO

The paper addresses the problem of distribution of high-definition video over fiber-wireless networks. The physical layer architecture with the low complexity envelope detection solution is investigated. We present both experimental studies and simulation of high quality high-definition compressed video transmission over 60 GHz fiber-wireless link. Using advanced video coding we satisfy low complexity and low delay constraints, meanwhile preserving the superb video quality after significantly extended wireless distance.

9.
Opt Lett ; 36(6): 858-60, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21403708

RESUMO

We propose and analyze a novel (to our knowledge) approach to implement the spectral self-imaging effect of optical frequency combs. The technique is based on time-domain multilevel phase-only modulation of a periodic optical pulse train. The method admits both infinite- and finite-duration periodic pulse sequences. We show that the fractional spectral self-imaging effect allows one to reduce by an integer factor the comb frequency spacing. Numerical simulation results support our theoretical analysis.

10.
BMC Cancer ; 11: 267, 2011 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-21702920

RESUMO

BACKGROUND: Extrahepatic biliary duct cancers (EBDC) are uncommon malignancies characterized by a poor prognosis with high rate of loco-regional recurrence. The purpose of the present study is to assess the feasibility and the potential impact of adjuvant radiotherapy (RT) in a series of patients treated in one institution. METHODS: Twenty three patients with non-metastatic bile duct cancer treated surgically with curative intent (4 gallbladder, 7 ampullary and 12 cholangiocarcinoma) received 3D conformal external beam RT to a median total dose of 50.4 Gy. Concurrent chemotherapy based on 5-FU was delivered to 21 patients (91%). Surgical margins were negative in 11 patients (48%), narrow in 2 (9%), and microscopically involved in 8 (35%). Eleven patients (55%) had metastatic nodal involvement. The average follow-up time for all patients was 30 months (ranging from 3-98). RESULTS: Acute gastrointestinal grade 2 toxicity (RTOG scale) was recorded in 2 patients (9%). Nausea or vomiting grade 1 and 2 was observed in 8 (35%) and 2 patients (9%) respectively. Only one patient developed a major late radiation-induced toxicity. The main pattern of recurrence was both loco-regional and distant (liver, peritoneum and/or lung). No difference was observed in loco-regional control according to the tumor location. The 5-year actuarial loco-regional control rate was 48.3% (67% and 30% for patients operated on with negative and positive/narrow/unknown margins respectively, p=0.04). The 5-year actuarial overall survival was of 35.9% for the entire group (61.4% in case of negative margins and 16.7% in case of positive/narrow/unknown margins, p=0.07). CONCLUSIONS: Postoperative RT with 50-60 Gy is feasible with acceptable acute and late toxicities. The potential benefit observed in our series may support the use of adjuvant RT in patients with locally advanced disease. Prospective randomized trials are warranted to confirm definitively the role of RT in this tumor location.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias dos Ductos Biliares/terapia , Ductos Biliares Extra-Hepáticos/patologia , Quimioterapia Adjuvante , Colangiocarcinoma/terapia , Radioterapia Adjuvante , Radioterapia Conformacional , Idoso , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/radioterapia , Neoplasias dos Ductos Biliares/cirurgia , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/mortalidade , Colangiocarcinoma/radioterapia , Colangiocarcinoma/cirurgia , Cisplatino/administração & dosagem , Terapia Combinada , Procedimentos Cirúrgicos do Sistema Digestório , Feminino , Fluoruracila/administração & dosagem , Humanos , Estimativa de Kaplan-Meier , Leucovorina/administração & dosagem , Irradiação Linfática , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Food Chem ; 279: 260-271, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30611489

RESUMO

In the present work, three Spanish local varieties of Prunus avium (L.), as well as two foreign varieties were studied. The content of total phenols, flavonoids, anthocyanins, glucose and fructose of methanolic extracts from ripe fruits of each variety were analysed. A phytochemical profile of these cultivars was performed by UHPLC-qTOF-MS. The employed chromatographic method allowed a clear and rapid separation of the three main phenolic compound groups present in the extracts: hydroxycinnamic acids, anthocyanins and flavonoids. In addition, the extracts DPPH radical scavenging ability, as well as their capacity to affect xanthine/xanthine oxidase system, were determined. Finally, variations in ROS intracellular concentrations in HepG2 cell line cultures treated with cherry extracts were measured through DCFH-DA assay. All extracts showed a significant inhibitory effect on the xanthine/xanthine oxidase system. Differences between in vitro and in cell culture results evidence the interaction among the phenolic compounds of the extract.


Assuntos
Antioxidantes/análise , Fenóis/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prunus avium/química , Antocianinas/análise , Antioxidantes/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Frutas/química , Células Hep G2 , Humanos , Espectrometria de Massas/métodos , Fenóis/química , Extratos Vegetais/análise
12.
Am J Hypertens ; 21(4): 400-5, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18369359

RESUMO

BACKGROUND: Although international guidelines for management of hypertension recommend optic fundus examination in the initial evaluation of hypertensive patients, there have been no studies to evaluate the usefulness of retinography in this application. METHODS: Two hundred and fifty consecutive new patients with hypertension but without known cardiovascular disease were studied. The average age was 57.2 years (s.d. 12.9) and 56% were men. The study was conducted in 14 primary care centers. Measurements included target organ damage (TOD) evaluation (electrocardiography, retinography, microalbuminuria, and serum creatinine) and blood pressure (BP) measurements. Outcome measurements were made to risk stratification according to 2003 World Health Organization and International Society of Hypertension (WHO-ISH) and 2007 European Society of Hypertension and European Society of Cardiology (ESH-ESC) guidelines, analyzed first without incorporating the retinography results and then reclassified using the retinography data. RESULTS: Advanced retinopathy was detected in 10.8%. The risk stratification arrived at as per the WHO-ISH guidelines, and without the retinography data was: 11.4% low risk, 62.4% moderate risk, and 26.2% high risk. When retinography results were taken into account, 8% from the moderate-risk group were reclassified to the high-risk group (11.4, 54.4, and 34.2%, respectively; P < 0.001). Using ESH-ESC guidelines, the risk stratification without the retinography data was 0.9% reference, 11.3% low, 58.8% moderate, 21.7% high, and 7.3% very high risk. With retinography, 10% were reclassified from a lower to a higher risk group (0.9, 10.4, 51.1, 20.4, and 17.2%, respectively; P < 0.001). CONCLUSIONS: As an alternative to optic fundus examination, retinography enables a more accurate cardiovascular risk stratification in the first evaluation after diagnosis of hypertension. When retinography is included in the assessment of cardiovascular risk, approximately 10% of patients are reclassified to a higher risk group.


Assuntos
Técnicas de Diagnóstico Oftalmológico/estatística & dados numéricos , Hipertensão/diagnóstico , Retina/patologia , Doenças Retinianas/diagnóstico , Adolescente , Adulto , Idoso , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial , Intervalos de Confiança , Feminino , Seguimentos , Fundo de Olho , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Prognóstico , Curva ROC , Doenças Retinianas/etiologia , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Índice de Gravidade de Doença
13.
Cancer Treat Rev ; 38(2): 111-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21652148

RESUMO

BACKGROUND: The role for adjuvant radiotherapy (ART) after curative resection in extrahepatic cholangiocarcinoma remains unclear. Due to the lack of randomized trials, available data comes from single center experiences or data-based population studies with inconclusive results. OBJECTIVE: To assess the impact of radiotherapy (with or without concurrent chemotherapy) on toxicity and survival of radically resected patients with extrahepatic bile duct cancer (extrahepatic cholangiocarcinoma, gallbladder cancer and pure ampullary cancer). DATA SOURCES AND STUDY SELECTION: Eligible studies with data on survival, recurrence and toxicity were retrieved from the MEDLINE, ISI web of science, EMBASE and Cochrane databases from January 1995 to December 2008, to ensure that all ART treatments were performed with conventional 3D techniques. In the absence of randomized controlled-studies, all observational cohort studies (longitudinal and historical) were initially considered. Ten retrospective cohort studies (where the use of concurrent CT was reported only in 2), met all inclusion criteria and were enrolled for final meta-analysis. Hazard ratio (HR) had to be extracted from survival curves using the Tierney et al. methods. MIX 1.7 statistical software was used for meta-analysis. RESULTS: All studies on ART used conventional 3D-techniques. Patients in the ART cohorts were more likely to have involved surgical margins and positive lymph nodes. For extrahepatic cholangiocarcinoma location, ART significantly improved overall survival (HR 0.62; 95% CI 0.48 to 0.78, p<0.001). Meta-analysis was not feasible for gallbladder cancer and ampullary cancer locations. Late radiation-induced toxicity was low (2-9% late obstruction or GI bleeding). CONCLUSION: In the absence of randomized controlled studies, we found in the present systematic review and meta-analysis of observational studies that, patients with extrahepatic cholangiocarcinoma treated with adjuvant RT have a significant lower risk of dying compared to patients treated with surgery alone.


Assuntos
Ductos Biliares Extra-Hepáticos/patologia , Neoplasias do Sistema Biliar/radioterapia , Neoplasias do Sistema Biliar/cirurgia , Adolescente , Adulto , Idoso , Neoplasias do Sistema Biliar/patologia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante , Adulto Jovem
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