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1.
Heliyon ; 10(10): e31364, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38826757

RESUMO

This research proposes designing and implementing a system to produce hydrogen, utilizing the thermal energy from the exhaust gases in a natural gas engine. For the construction of the system, a thermoelectric generator was used to convert the thermal energy from the exhaust gases into electrical power and an electrolyzer bank to produce hydrogen. The system was evaluated using a natural gas engine, which operated at a constant speed (2400 rpm) and six load conditions (20 %, 40 %, 60 %, 80 %, and 100 %). The effect of hydrogen on the engine was evaluated with fuel mixtures (NG + 10 % HEF and NG + 15 % HEF). The results demonstrate that the NG + 10 % HEF and NG + 15 % HEF mixtures allow for a decrease of 1.84 % and 2.33 % in BSFC and an increase of 1.88 % and 2.38 % in BTE. Through the NG + 15 % HEF mixture, the engine achieved an energy efficiency of 34.15 % and an exergetic efficiency of 32.84 %. Additionally, the NG + 15 % HEF mixture reduces annual CO, CO2, and HC emissions by 9.52 %, 15.48 %, and 13.39 %, respectively. The addition of hydrogen positively impacts the engine's economic cost, allowing for a decrease of 1.56 % in the cost of useful work and a reduction of 3.32 % in the cost of exergy loss. In general, the proposed system for hydrogen production represents an alternative for utilizing the residual energy from exhaust gases, resulting in better performance parameters, reduced annual pollutant emissions, and lower economic costs.

2.
Heliyon ; 8(11): e11545, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36419662

RESUMO

A large proportion of annual production of worldwide greenhouses gases results from the use of internal combustion engines. This experimental work evaluates the influence of dual-fuel operation on the overall emissions of a low-displacement compression-ignition engine based on operational conditions such as torque, rotational speed, and load. Hydroxy gas is used as a supplementary gaseous fuel while using pure diespel or palm oil biodiesel as baseline fuels. The CO, CO2, NOx, and HC emissions levels were carefully characterized through experimental measurements and statistical analysis. The influence of hydroxy enrichment was also examined on the engine's fuel consumption. The study incorporates an in-house hydroxy generator to store and supply the gas in the intake air system using an electrolyzer. The results demonstrated that the ANOVA analysis provides accurate predictions compared to experimental measurements with less than 5% relative error. The use of hydroxy reduces the SFC by up to 25%, which represents an economic advantage of dual-fuel operation, additionally it decreases CO, HC, and CO2 emissions. However, with hydroxy enrichment, NOx emissions levels escalate at medium and high loads. Overall, hydroxy enrichment demonstrates to be a robust alternative from an environmental and economic perspective. Future research will be focused on evaluating the biodiesel - hydroxy dual operation, broadening the spectrum of biodiesel concentration percentages, and selecting different raw materials for biofuel production.

3.
Urol Case Rep ; 45: 102243, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36185753

RESUMO

Testicular germ cell tumors, including seminomas, originate mainly from the testicles and rarely from extragonadal locations, often retroperitoneum and mediastinum. Moreover, primary seminal vesicle tumors are extremely rare, and the most described histology is adenocarcinoma. We report, as far as we know, the second case of primary seminoma of the seminal vesicle.

4.
Urol Oncol ; 40(4): 169.e13-169.e20, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35260297

RESUMO

INTRODUCTION: Penile aesthetics after partial penectomy (PP) for penile cancer (PC), significantly affect a patient's health-related quality of life (HRQoL), self-esteem, and sexual function. Satisfactory reconstruction has become a major milestone in the treatment of these patients. METHODS: Clinical charts of all patients that underwent PP and reconstruction with an inverted urethral flap (IUF) were reviewed. The primary endpoints were recurrence-free survival (RFS), overall survival (OS), and progression-free survival (PFS) which were graphically represented by Kaplan-Meier estimates. The key secondary endpoints were Health-related quality of life (HRQoL), erectile function, and lower urinary tract symptoms. RESULTS: Between May 2007 and December 2019, 74 patients with PC underwent PP and IUF reconstruction. The median age was 62 years (IQR 52-76), median follow-up was 72 months (IQR 38-121). Twenty-nine patients (39.2%) underwent inguinal lymph node dissection, 62 (83.8%) underwent dynamic sentinel lymph node biopsy. Kaplan-Meier estimates of OS, RFS, and PFS showed a 6-year OS of 86.5%, 6-year RFS of 90.5%, and a 6-year PFS of 85.1%. Regarding functional outcomes, we found a mean global health score of 84.6% ± 10.4 at the EQ-5D-3L-VAS. The mean Voiding score of the ICIQ-MLUTS was 1.7 ± 3.2 and a mean IIEF-5 score of 17.3 ± 7. CONCLUSIONS: To the best of our knowledge, we report the largest cohort in the literature of PP with IUF reconstruction. These results are important since early-stage PC is the most common stage at diagnosis. In carefully selected patients' preservation of a longer urethral stump to allow for the inverted flap is safe and does not compromise oncological outcomes while preserving HRQoL.


Assuntos
Neoplasias Penianas , Qualidade de Vida , Humanos , Masculino , Pessoa de Meia-Idade , Ereção Peniana , Neoplasias Penianas/patologia , Pênis/cirurgia , Estudos Retrospectivos , Uretra/patologia , Uretra/cirurgia
5.
Urol Oncol ; 39(12): 839.e1-839.e8, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34400069

RESUMO

INTRODUCTION: Penile cancer (PC) is an aggressive malignancy in which the most important prognostic factor for cancer specific survival (CSS) is the involvement of regional lymph nodes (LNs). Lymph node density (LND) could become a superior prognostic tool for CSS, by accounting for both extent of dissection and nodal disease burden. We aim to validate LND as a prognostic factor for CSS in a contemporary series of patients with PC treated and followed at a single high-volume center, treating more than 25 PC patients per year, over a 13-year period. METHODS: Clinical charts of all patients with PC who underwent surgical treatment between 2007 and 2020 were reviewed. Clinicopathological data was collected and analyzed retrospectively. We only included patients with ≥ 8 LNs removed in a unilateral ILND or ≥16 LNs when a bilateral approach was used. We attempted to find an optimal threshold for LND, capable of maximizing effect difference in terms of CSS and RFS between dichotomized groups. To determine this threshold, we used the chi-squared and the Mann-Whitney tests, and it was required to fulfill the proportional hazards assumption. We assessed different thresholds previously reported in the literature. In our study the optimal threshold for LND was determined to be ≤ 20% Descriptive statistics were used to summarize patient characteristics, CSS and RFS were graphically represented by Kaplan-Meier estimates. Harrell's C index for CSS and RFS were calculated for LND and pN stage, to determine which variable has a superior predictive capacity RESULTS: We identified 110 patients with PC who underwent ILND at our institution, of these, 87 were node-positive and were included in the final analysis. Overall estimates of CSS showed a 3-year CSS of 43% (95% CI: 32-54), the estimated 3-year CSS for the patients with a LND ≤ 20% was 69% (95% CI: 50-82) and 26% (95% CI: 14-39) in the group with a LND >20% (Log-rank P = 0.001). The estimated 3-year RFS for the patients with LND ≤ 20% was 61% (95% CI: 42-76) and 30% (95% CI: 16-44) in the group with a LND >20% (Log-rank P = 0.009). The results of univariate analysis indicate that in patients with a LND >20% the risk for cancer specific mortality was increased (HR 2.68; 95% CI: 1.45-4.98, P =  0.002) compared with LND ≤ 20%. In the and Cox multivariate analysis after Adjusting for age and pN stage the association increased (HR 2.73; 95%, CI 1.38-5.40, P = 0.004). Harrell´s C index for CSS was 0.63 for LND vs. 0.54 for pN stage, suggesting a 9% higher concordance for LND and CSS. CONCLUSIONS: Lymph node density stands as a promising tool for risk-stratifying patients with node-positive PC after ILND. In this retrospective study, LND was a significant predictor of CSS and RFS when using a LND >20% threshold, and also showed a superior predictive ability than pN stage. These results support the use of the LND parameter in clinical practice with a final goal to improve risk stratification, and individualized adjuvant treatment decision-making to patients with high-risk of cancer specific mortality.


Assuntos
Canal Inguinal/patologia , Linfonodos/patologia , Neoplasias Penianas/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Penianas/mortalidade
6.
Urology ; 156: 199-204, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34310915

RESUMO

OBJECTIVE: To report survival trends and oncological outcomes of penile cancer surgically treated patients, at a high-volume center, treating more than 25 patients each year, in a high incidence country. METHODS: Clinical charts of all patients that underwent surgical management for penile cancer were reviewed. The primary end points were cancer specific survival (CSS), progression-free survival, and local recurrence free survival. Kaplan-Meier plots were used for survival analyses. Multivariate analysis was performed using cox proportional hazard age-adjusted models to determine the effect of pN, pT, lymphovascular invasion for CSS. RESULTS: A total of 209 patients were identified, with a median follow up of 96 months (IQR 49-133). Organ-sparing surgerywas performed in 72.7%, 56.9% underwent dynamic sentinel lymph node biopsy, 110 patients underwent inguinal lymph node dissection, and 45 (21.5%) pelvic lymph node dissection. A total of 75 (35.8%) of patients relapsed, median time to relapse of 12 months (IQR 6-25). Overall estimates of CSS showed an 8-year CSS of 68.9%. Eight-year CSS was 90.5% for N0, and 32.8% in pN3 (P <.001). The Cox proportional hazard model showed that pN1-3, pT2-4, lymphovascular invasion and positive dynamic sentinel lymph node biopsy were the variables associated with worse 8-year CSS. CONCLUSION: To the best of our knowledge, we report one of the largest cohorts on the survival outcomes of penile cancer surgical treatment, in a single institution, over a long period of time, were most patients are referred with high-risk, locally advanced or nodal disease.


Assuntos
Neoplasias Penianas/mortalidade , Neoplasias Penianas/cirurgia , Idoso , Colômbia , Hospitais com Alto Volume de Atendimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Penianas/patologia , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
7.
Rev. crim ; 63(1): 61-76, 20/04/2021.
Artigo em Espanhol | LILACS | ID: biblio-1247627

RESUMO

El presente estudio tuvo como objetivo general determinar el grado de afectación que presenta la prueba Griess (a y b), al interior del cañón del arma de fuego tipo escopeta, marca Benelli, modelo Súper Nova, con la trasmisión de los contaminantes aceite, agua lluvia, diésel y gasolina. Surge la necesidad de indagar si los contaminantes establecidos pueden afectar la realización del procedimiento descrito en el numeral 4.1 de la guía 2DCGU-0024 "realizar procedimientos balísticos a las armas (de fuego, neumáticas, de gas, fisto, detonadoras, eléctricas, entre otras) e ingreso a los sistemas de identificación balística". La metodología utilizada fue de tipo experimental, para ello se realizó una cantidad importante de ensayos, se manipularon las soluciones A y B del reactivo de GRIESS. Como resultado se evidenció que los agentes contaminantes transferidos al interior del cañón (aceite 4 tiempos, diésel y gasolina) no afectan los resultados para la identificación de nitritos producto de la combustión durante el fenómeno del disparo, caso contrario ocurre con el agua lluvia, ya que se observa que esta afecta la elaboración de la prueba, teniendo en cuenta que sin entrar en contacto con la pólvora deflagrada, arroja como resultado una coloración rosada tenue, que indica de forma preliminar que es positiva para la presencia de nitritos.


This study's general objective was to determine the degree of impact a GRIESS test (a and b) may have on the inside of a Benelli Supernova shotgun barrel by transmitting contaminants, such as oil, rain water, diesel and gasoline. The need arose to research whether or not the established contaminants can affect performing the procedure described in clause 4.1 of guide 2DC-GU-0024 on "performing ballistic testing on weapons (firearms, pneumatic, gas, black powder, detonating, electrical, etc.) and entering ballistic identification systems." The methodology was experimental. A high number of tests were carried out, manipulating components A and B of the GRIESS reagent. As a result, it was observed that contaminating agents transferred within a barrel (4-stroke engine oil, diesel and gasoline) do not affect the results of identifying nitrates resulting from combustion during firearm discharge. The opposite occurs with rain water, since it was observed that is affects preparing evidence, taking into account that it yields a light pink coloration as a result without coming into contact with combusted gunpowder, which preliminarily indicates that it tested positive for the presence of nitrites.


O objetivo geral do presente estudo foi determinar o grau de afetação que o teste de GRIESS (a e b) apresenta, dentro do cano da arma de fogo tipo espingarda, marca Benelli, modelo Super Nova, com a transmissão dos contaminantes: óleo, água da chuva, diesel e gasolina. Surge a necessidade de investigar se os contaminantes estabelecidos podem afetar o desempenho do procedimento descrito no numeral 4.1 do guia 2DC-GU-0024 "realizar procedimentos balísticos em armas (armas de fogo, pneumáticas, gás, fisto, detonantes, elétricos, entre outros) e acesso a sistemas de identificação balística". A metodologia utilizada foi experimental, nesse sentido, foi realizado um número significativo de testes, e as soluções A e B do reagente de GRIESS foram manipuladas. Como resultado, ficou evidente que os agentes contaminantes transferidos para o interior do cano (óleo 4 tempos, diesel e gasolina) não afetam os resultados para a identificação de nitritos produto da combustão durante o fenômeno de queima. O contrário ocorre com a água da chuva, pois observa-se que isso afeta o preparo do teste, visto que, sem entrar em contato com a pólvora deflagrada, produz uma leve coloração rosa, o que preliminarmente indica que é positivo para a presença de nitritos.


Assuntos
Humanos , Armas de Fogo , Gunpowder , Substâncias Explosivas
8.
Data Brief ; 30: 105369, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32258265

RESUMO

In this paper, operational data of a natural gas-fired generation engine at 2 MW of power is presented. This engine is used as part of the power supply system of a flexible packaging transformation and conversion plant. This plant, besides having the power supply generated by the engine, receives electrical energy from the network. The data collected from this engine corresponds to measurements taken before, during and after engine stops, whether due to engine maintenance stops, engine failures or external power grid failures. The measurement was made every 10 seconds, and for the storage of these data a data acquisition software was used, which, besides allowing to take these data, shows in real time the electrical behavior of the electrical supply system, as well as the mechanical behavior of the engine.

9.
urol. colomb. (Bogotá. En línea) ; 29(2): 84-90, 2020. ilus
Artigo em Inglês | LILACS, COLNAL | ID: biblio-1402763

RESUMO

Zoom Image Abstract Introduction Penile carcinoma is an aggressive disease with catastrophic consequences that frequently lead to death. Therefore, further knowledge on the prognostic factors that can help identify patients in need of more aggressive treatments becomes essential. Objective To identify the prognostic factors for lymph node (LN) involvement and tumor recurrence in patients diagnosed with squamous cell carcinoma of the penis (SCCP). Methods A retrospective cohort study was conducted. Patients diagnosed and treated for SCCP at Instituto Nacional de Cancerología between 2008 and 2015 were included in the sample. Cases in which no information on recurrence was available for the follow-up were excluded, as well as patients with no initial pathology and those getting penile reconstructions after cancer. Relevant data was retrieved from the medical records of each patient, and a descriptive analysis was performed. Subsequently, this data was used to apply a logistic regression model to determine the potential clinical and histopathological prognostic factors. Results A total of 104 patients were included in the present study. The average age of the sample was 59 years, while the follow-up averaged 24 months per patient. Inguinal lymphadenectomy was performed on 61 patients (59%) during the follow-up. The logistic regression model showed that lymphovascular invasion (odds ratio [OR]: 6.7; 95% confidence interval [95%CI]: 1.2­35) and poor tumor differentiation (OR: 17; 95%CI: 3.2­92) were associated with tumor recurrence. Likewise, the lymphadenectomy procedures showed that lymphovascular invasion was associated with LN involvement (OR: 3.3; 95%CI: 1.1­10). Conclusion Lymphovascular invasion was the strongest prognostic factor observed in our sample, aiding in the prediction of inguinal LN involvement and tumor recurrence in SCCP patients


Introduccion El cáncer de pene es una enfermedad agresiva con consecuencias catastróficas que frecuentemente llevan a la muerte. Por lo tanto, es esencial un mayor conocimiento sobre los factores pronósticos que pueden ayudar a identificar a los pacientes que necesitan tratamientos más agresivos. Objetivo Identificar los factores pronósticos patológicos de compromiso ganglionar inguinal y recaída tumoral en pacientes con carcinoma escamocelular de pene. Métodos Se realizó un estudio de cohorte retrospectivo. Se incluyeron en la muestra pacientes diagnosticados y tratados por carcinoma escamocelular de pene (SCCP) en el Instituto Nacional de Cancerología entre 2008 y 2015. Los casos en los que no había información sobre la recurrencia en el seguimiento fueron excluidos, así como los pacientes sin patología inicial y aquellos que reciben reconstrucciones del pene después del cáncer. Se recuperaron los datos relevantes de los registros médicos de cada paciente, y una descripción fue realizada. Posteriormente, estos datos se utilizaron para aplicar un modelo de regresión logística para determinar los posibles factores pronósticos clínicos e histopatológicos. Resultados Un total de 104 pacientes fueron incluidos en el estudio. La edad promedio de la muestra fue de 59 años, mientras que el seguimiento promedió fue de 24 meses por paciente. La linfadenectomía inguinal se realizó en 61 pacientes (59%) durante el seguimiento. El modelo de regresión logística mostró que la invasión linfovascular (odds ratio [OR]: 6,7; intervalo de confianza del 95% [IC 95%]: 1,2­35) y la pobre diferenciación tumoral (OR: 17; IC 95%: 3,2­92) se asociaron con recurrencia tumoral. Así mismo, los procedimientos de linfadenectomía mostraron que la invasión linfovascular se asoció con afectación de LN. (OR: 3,3; IC 95%: 1,1-10). Conclusión La invasión linfovascular es el factor pronóstico independiente más importante que se asocia de manera independiente con compromiso ganglionar inguinal positivo y recaída tumoral.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Penianas , Excisão de Linfonodo , Patologia , Carcinoma , Carcinoma de Células Escamosas , Razão de Chances , Linfonodos , Oncologia
10.
Heliyon ; 5(10): e02700, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31687522

RESUMO

This paper presents the application of a systematic methodology to obtain a semi-physical model of phenomenological base for a 2 MW internal combustion engine to generate electric power operating with natural gas, as a function of the average thermodynamic value normally measured in industrial applications. Specifically, the application of the methodology is focused on the cylinders, exhaust manifold, and turbocharger turbine sections. The proposed model was validated with actual operating data, obtaining an error rate not exceeding 5%, which allow a thermal characterization of the Jenbacher JMS 612 GS-N based on the model. A parametric analysis is conducted; considering the volumetric efficiency, the output electric power, the effective efficiency, the exhaust gas temperature, the turbine mass flow, the specific fuel consumption under the nominal operation conditions, which is 1.16 bar in the gas pressure, 65 °C in the cooling water temperature, 35 °C in the average ambient temperature, and 1500 rpm. The results of this model can be used to evaluate the thermodynamic performance parameters of waste heat recovery systems. On the other hand, new control strategies and the implementation of state observers for the detection and diagnosis of failures can be developed based on the proposed model.

11.
Urol. colomb ; 27(3): 290-293, 2018. Ilus
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-981891

RESUMO

El hallazgo incidental de tumores renales T1a se ha incrementado en la última década.1 La cirugía preservadora de nefronas sigue siendo el gold standard de manejo en pacientes con tumores renales pequeños, con resultados oncológicamente equiparables a la nefrectomía radical y reduciendo el impacto negativo en la función renal.2,3 La ablación por radiofrecuencia (RFA), es una alterativa mínimamente invasiva cuya técnica causa la destrucción del tumor mediante el calentamiento.4,5 Puede ser realizada mediante cirugía abierta o laparoscópica y por vía percutánea guiada por tomografía axial o ecografía. La evidencia sustancial indica que la RFA de tumores renales pequeños es efectiva en la erradicación tumoral completa.6­8


The incidental finding of T1a kidney tumors has increased in the last decade.1 Surgery nephron-preserving remains the gold standard of management in patients with small renal tumors, with results oncologically comparable to radical nephrectomy and reducing the negative impact on renal function.2,3 Radio Frequency Ablation (RFA) is a minimally invasive alterative technique whose technique causes tumor destruction by heating.4,5 It can be performed by open or laparoscopic surgery and percutaneously guided by axial tomography or ultrasound. Substantial evidence indicates that RFA of small renal tumors is effective in complete tumor eradication.6-8


Assuntos
Humanos , Abdome , Neoplasias , Ondas de Rádio , Nefrectomia
12.
Urol Case Rep ; 12: 42-44, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28316937

RESUMO

Introducing the topic of abdominal wall metastasis secondary to prostate cancer with a reminder of the disease's rarity, being the first published case. This article is about a 66 year old patient diagnosed with prostate cancer [cT2aNxMx iPSA: 5,6 ng/ml Gleason 3+3, (Grade 1 Group)], treated with radical prostatectomy as well as accompanied with amplified pelvic lymphadenectomy, who subsequently presented metastatic lesions to the abdominal wall diagnosed with PET/CT Gallium 68-PMSA technique and treated with abdominal metastasectomy with adequate short term results.

13.
Rev. colomb. cienc. pecu ; 27(4): 290-298, oct.-dic. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-735088

RESUMO

Background: reports from traditional medicine suggest that chard (Beta vulgaris L. var Cicla) can have remarkable effects in diabetes therapy. Objective: to evaluate the cytotoxic activity of chard extracts in cell lines and determine the viability of cultured porcine pancreatic islets added with or without chard extracts. Methods: cytotoxic activity of chard extracts was assessed in non-tumor and tumor cell lines using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] technique, and the ability of extracts to maintain porcine pancreatic islets viability and regeneration in vitro was tested. Results: the 50% cytotoxic concentration (CC50) of extracts for non-tumor cell lines was above 1,000 μg/mL, while it was 825 μg/mL, 283 μg/mL, 136 μg/mL and 380 μg/mL, for hexane, ethyl acetate, ethanol and water extracts in the tumor cell line, respectively. The CC50 ratio between cell lines indicates that ethanol extract is 7.5 times more toxic to tumor than non-tumor cell lines. There was an increase in viability of porcine pancreatic islets cultured with aqueous, ethyl acetate, and ethanol extracts compared with standard media (CMRL1066) and Cyclosporine A (CsA) control groups. Furthermore, a greater than one regeneration index of islets cultured with ethanol extract at 1,000 μg/mL and 500 μg/mL concentrations during 15 days was observed, which remained constant and was significantly higher than CsA group. Conclusions: these results suggest that chard metabolites should be researched to develop antitumor therapies and human pancreatic islets recovery in diabetes treatment.


Antecedentes: reportes de medicina tradicional sugieren que la planta acelga (Beta vulgaris L. var Cicla) es importante en el tratamiento de enfermedades como la diabetes. Objetivo: evaluar la citotoxicidad de concentraciones de extractos de acelga en líneas celulares y determinar la viabilidad de islotes pancreáticos porcinos cultivados con y sin extracto de acelga. Método: se evaluó la actividad citotóxica en líneas celulares tumorales y no tumorales, con la técnica del MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. Específicamente se hicieron ensayos para comprobar si los extractos de acelga tienen la capacidad de mantener la viabilidad de islotes pancreáticos porcinos aislados e influir en su regeneración in vitro. Resultados: la concentración citotóxica al 50% (CC50) de los extractos en líneas no tumorales fue mayor de 1.000 μg/mL, mientras que para los extractos en hexano, acetato de etilo, etanol y agua fue de 825 μg/mL, 283 μg/mL, 136 μg/mL y 380 μg/mL, respectivamente, en líneas tumorales. La proporción CC50 encontrada indica que el extracto en etanol es 7,5 veces más tóxico para las líneas celulares tumorales que para las no tumorales. Igualmente encontramos un aumento en la viabilidad de los islotes pancreáticos porcinos cultivados con extracto acuoso, de acetato en etilo y etanol en comparación con el medio de cultivo estándar (CMRL1066) y un control inhibidor que contenía medio con Ciclosporina A (CsA). Además, se encontró que el índice de regeneración era mayor de uno en los islotes cultivados con el extracto en etanol a concentraciones de 1.000 μg/mL y 500 μg/mL durante 15 días, que se mantuvo constante y fue significativamente mayor en comparación con el grupo de CsA. Conclusión: estos resultados sugieren que los metabolitos de la acelga podrían ser utilizados en la investigación de nuevos fármacos para el desarrollo de terapias antitumorales y recuperación de islotes pancreáticos en el tratamiento de la diabetes.


Antecedentes: relatos encontrados em medicina sugerem que a planta acelga (Beta vulgaris L. var Cicla) tem un papel importante no tratamento das doenças como a diabetes. Objetivo: avaliar a citotoxicidade de concentrações de extratos em linhagens celulares e determinar a viabilidade de ilhotas pancreáticas de porcos cultivadas com e sem extrato de acelga. Métodos: neste trabalho foi avaliada a atividade citotóxica dos extratos da acelga em linhagens celulares tumorais e não tumorais, usando a técnica do MTT [3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide]; além disso, foram feitos ensaios para verificar a capacidade que têm os extratos para manter a viabilidade das ilhotas pancreáticas isoladas de porcos e a influência em sua regeneração in vitro. Resultados: a concentração citotóxica ao 50% (CC50) dos extratos em linhagens não tumorais está acima de 1000 μg/mL, enquanto para os extratos de hexano, acetato de etilo, etanol y água é de 825 μg/mL, 283 μg/mL, 136 μg/mL y 380 μg/mL, respectivamente, em linhagens tumorais. A proporção CC50 entre a célula indica que o extrato de etanol é 7,5 vezes mais tóxico para as linhas celulares tumorais que para as linhas não tumorais. Houve um aumento na viabilidade dos isolados pancreáticos de porcos cultivados com extrato aquoso, de acetato de etilo y etanol, em comparação com o meio de cultura padrão (CMRL 1066) e um controle inibitório contendo meio com Ciclosporina A (CsA). Encontrou-se também uma taxa de regeneração maior do que um em ilhotas cultivadas com concentrações de 1000 μg/mL e 500 μg/mL durante 15 días, que se manteve constante e foi significativamente mais elevada em comparação com a CsA. Conclusões: estes resultados sugerem que os metabolitos da acelga poderiam ser usados para a pesquisa de novas drogas para o desenvolvimento de terapias antitumorais e recuperação de ilhotas pancreáticas para o tratamento da diabetes.

14.
Rev. salud bosque ; 3(2): 17-22, 2013. tab
Artigo em Espanhol | LILACS | ID: lil-772955

RESUMO

El propósito de este estudio es evaluar la composición química de tres cementos: Portland tipo I (CEMEX Samper , Cundinamarca, Colombia), Portland tipo I (CEMEX-Diamante, Ibagué, Colombia) y ProRoot MTA (Dentsply-Maillefer, Ballaigues, Suiza). Se utilizó una muestra probabilística de 17 pastillas para cada tipo de cemento. El análisis se llevó a cabo con la microsonda EDAX (Mahwah, NJ, USA) del microscopio de barrido electrónico SEM FEI (Quanta 200, Hillsboro, Oregon USA), bajo condiciones estandarizadas de lectura de las muestras. Se hicieron cuatro lecturas por muestra, para un subtotal de 68 lecturas por cada tipo de cemento y un total de 208 lecturas. Los resultados se obtuvieron en porcentaje de peso sólido por elemento. Los datos generales fueron analizados por las pruebas ANOVA, comparaciones múltiples de Tukey y t de Student. Se observaron tres elementos comunes entre los tres cementos: Ca, Si y Al, pero se encontraron diferencias estadísticamente significativas de los elementos comunes entre el cemento ProRoot MTA y los cementos Portland I. El Bi solo se encontró en el ProRoot MTA y el S solo se encontró en los cementos Portland tipo I. Se concluye que la composición de los tres cementos es similar. Sin embargo, es necesario evaluar el impacto que puede tener, tanto la presencia de S en los cementos Portland I, como la diferencia de concentraciones de los elementos que fueron comunes en los tres cementos en cuanto a biocompatibilidad y efectividad clínica.


The objective of this study is to evaluate the chemical composition of three cements: Portland Type I (CEMEXSamper , Cundinamarca, Colombia), Portland Type I (CEMEX-Diamante, Ibague, Colombia) and Pro Root MTA (Dentsply-Maillefer, Ballaigues, Switzerland). A probabilistic sample of 17 tablets for each type of cement was used. The analysis was carried out with energy dispersive analysis with x-rays (EDAX) (Mahwah, NJ, USA) in the scanning electron microscope (SEM) FEI (Quanta 200, Hillsboro, Oregon, USA) under standard sample reading conditions. Four readings per sample were carried out for a total of 68 readings per cement, and a grand total of 208 readings. The results were obtained as a percentage of solid weight per element. General data was analyzed with the ANOVA test, and Tukey and t of Student multiple comparison tests. Three common elements were observed between the three cements: Ca, Si, and Al, but there were significant statistical differences between the common elements of the ProRoot MTA and the Portland cements I. The Bi was found only in the ProRoot MTA, and the S only in the Portland type I cements. It can be concluded then that the composition of the three cements is similar; however, it is necessary to evaluate the impact that the presence of S in the Portland I cements as well as the difference in concentrations of the three common elements may have in the biocompatibility and clinical effectiveness.


Assuntos
Fenômenos Químicos/métodos , Cemento Dentário/química , Ortodontia , Tratamento do Canal Radicular , Colômbia
15.
Radiology ; 252(2): 551-60, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19508985

RESUMO

PURPOSE: To evaluate two methods of summarizing tomographic diffuse optical spectroscopic (DOS) data through region-of-interest (ROI) analysis to differentiate complete from incomplete responses in patients with locally advanced breast cancer undergoing neoadjuvant treatment and to estimate the standard deviations of these methods for power analysis of larger study designs in the future. MATERIALS AND METHODS: Subjects participating in the HIPAA-compliant imaging study, approved by the institutional review board, provided written informed consent and were compensated for their examination participation. Seven of 16 cases in women with complete study data were analyzed by using both fixed- and variable-size (full-width-at-half-maximum) ROI measures of the DOS total hemoglobin concentration (Hb(T)), blood oxygen saturation, water fraction, optical scattering amplitude, and scattering power in the ipsilateral and contralateral breasts. Postsurgical histopathologic analysis was used to categorize patients as having a complete or incomplete treatment response. RESULTS: Average normalized change in Hb(T) was the only DOS parameter to show significant differences (P < or = .05) in the pathologic complete response (pCR) and pathologic incomplete response (pIR) outcomes in seven patients. Mean values of the changes for fixed-size ROIs were -64.2% +/- 50.8 (standard deviation) and 16.9% +/- 38.2 for the pCR and pIR groups, respectively, and those for variable-size ROIs were -96.7% +/- 91.8, and 14.1% +/- 26.7 for the pCR and pIR groups, respectively. CONCLUSION: Tomographic DOS may provide findings predictive of therapeutic response, which could lead to superior individualized patient treatment. SUPPLEMENTAL MATERIAL: http://radiology.rsnajnls.org/cgi/content/full/2522081202/DC1.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Interpretação de Imagem Assistida por Computador/métodos , Nefelometria e Turbidimetria/métodos , Análise Espectral/métodos , Tomografia Óptica/métodos , Adulto , Idoso , Quimioterapia Adjuvante/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Avaliação de Resultados em Cuidados de Saúde/métodos , Prognóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
16.
J Neurosurg Pediatr ; 2(6): 438-44, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19035694

RESUMO

OBJECT: In 2002, "quick-brain" (QB) MR imaging (ultrafast spin echo T2-weighted imaging) was introduced as an alternative technique to CT scanning for assessing children with hydrocephalus. The authors have observed high patient and physician satisfaction with this technique at their institution, which has led to an increasing frequency of its use for nonhydrocephalic indications. The goal in this study was to characterize, quantitate, and assess the use of QB MR imaging for these additional indications. METHODS: Between February 2003 and December 2007, 1146 consecutive QB MR imaging studies were performed, and the findings were entered prospectively into a radiology database. All available clinical records were retrospectively reviewed to assign > or = 1 of the following indications to each study: hydrocephalus, macrocephaly, Chiari malformation, intracranial cyst, screening prior to lumbar puncture, screening for congenital anomalies, trauma, and other. Changes in the distribution of indications over time and clinical experience for each indication were reviewed. RESULTS: The total number of QB imaging studies performed increased each year. The proportion of studies performed for nonhydrocephalic indications also increased (from 23 to 50%). The most common indication was screening for macrocephaly, and all other indications were nearly evenly distributed. Quick-brain MR imaging was used extensively for the initial evaluation and follow-up in patients with little need for additional studies. Its false-negative rate, however, remains unknown. CONCLUSIONS: The role of QB MR imaging for nonhydrocephalic indications is expanding, and it appears promising for a number of screening and surveillance paradigms. "Quick-brain plus" protocols for specific indications may add sensitivity and are under development.


Assuntos
Encefalopatias/diagnóstico , Imageamento por Ressonância Magnética/estatística & dados numéricos , Adolescente , Adulto , Idoso , Encefalopatias/etiologia , Encefalopatias/terapia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Padrões de Prática Médica/estatística & dados numéricos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
17.
Rev. colomb. cienc. pecu ; 20(3): 241-249, jul.-sep. 2007. graf, tab
Artigo em Espanhol | LILACS | ID: lil-636035

RESUMO

Hojas de las plantas Hura crepitans y Codiaeum variegatum se recolectaron en la ciudad de Medellín (Colombia), para determinar la actividad biológica (Actividad citotóxica [AC] y antiviral [AAV]) de cuatro extractos de éstas (hexánico, en acetato de etilo, metanólico y acuoso) sobre los virus de Estomatitis Vesicular (VSV) serotipos Indiana y New Jersey y Herpes Virus Bovino tipo-1 cepa Bogotá (BHV-1B). El tamizaje de actividad biológica de los extractos se realizó en monocapas de células BHK-21. Luego los extractos promisorios, pasaron a la fase cuantitativa de AAV por el ensayo de MTT [3-(4,5-dimethylthiazol–2-yl)-2,5-diphenyltetrazolium bromide] para determinar la concentración citotóxica 50 (CC50), la concentración inhibitoria 50 (IC50) y el índice de selectividad (IS). Ninguno de los extractos de las cuatro plantas presentó AAV contra VSV, mientras que los extractos hexánico, en acetato de etilo y metanólico de H. crepitans confirieron resistencia a la infección por BHV-1B con IC50 de 17.41, 7.87 y 2.75 µ g/ml, respectivamente. El extracto con mejor IS (relación entre IC50 y CC50) fue el hexánico de H. crepitans (IS > 17.4). Estos resultados sugieren que pueden existir compuestos en el extracto hexánico de H. crepitans con una actividad promisoria anti BHV-1B. Este estudio es pionero en demostrar actividad antiviral de extractos de plantas de la especie Euphorbiaceae contra BHV-1B.


Leaves from Hura crepitans and Codiaeum variegatum plants were collected in Medellín, Colombia to determine its cytotoxic [CA] and antiviral activity [AVA]. Four extracts were prepared using hexane, ethyl acetate, methanol and water; the antiviral activity was tested against Vesicular Stomatitis Virus (VSV), serotypes Indiana and New Jersey and Bovine Herpes Virus (type 1 Bogotá strain). The preliminary biological activity of each of the eight extracts was determined on BHK-21 cell monolayers using 96 well-plates. Then, promissory extracts were further tested using the MTT [3-(4,5-dimethylthiazol–2-yl)-2,5-diphenyltetrazolium bromide] assay to determine the cytotoxic concentration 50 (CC50), the inhibitory concentration 50 (IC50 ), and the selectivity index (SI). None of the evaluated plants exhibited AVA against VSV, whereas the extracts in hexane, ethyl acetate and methanol from Hura crepitans protected cell monolayer from infection against BHV-Bogotá with IC50 of 17.41, 7.87 and 2.75 µ g/ml respectively. The best IS was hexane of H. crepitans (SI > 17.4). These results suggest that this extract contains antiviral compounds. This research is pioneer demonstrating AVA against BHV-1B in extracts from plants of the Euphorbiaceae family.

18.
Vitae (Medellín) ; 14(1): 55-60, ene.-jun. 2007. tab
Artigo em Espanhol | LILACS | ID: lil-502205

RESUMO

Los virus causan enfermedades humanas y animales de gran importancia epidemiológica y económica, para la mayoría de las cuales no existen tratamientos satisfactorios, o con las terapias se generan cepas resistentes. Extractos de plantas pertenecientes a la familia Euphorbiaceae han mostrado actividad contra virus de la familia Herpesviridae. Utilizando la técnica de tinción en placa con cristal violeta, se evaluó la citotoxicidad y la actividad antiviral de los extractos en hexano, en acetato de etilo, en metanol y en agua de las especies Caryodendron orinocense y Phyllanthus niruri contra los virus del Herpes Simplex tipo 2 (HSV-2) y del Herpes Bovino tipo 1 (HVB-1). Además, se realizó un estudio fitoquímico preliminar de las dos especies. En general, los extractos de las especies estudiadas muestran citotoxicidad a concentraciones mayores de 250 μg/mL. El extracto en acetato de etilo de la especie Caryodendron orinocense fue el que registró el mayor factor de reducción viral para HSV-2 y HVB-1, el cual fue de 102 a una concentración de 125 μg/ml y de 104 a 62.5 μg/ml respectivamente. Las especies estudiadas muestran una composición química determinada principalmente por aminoácidos, compuestos fenólicos, taninos y triterpenoides, metabolitos que podrían estar involucrados en su actividad antiviral.


Assuntos
Herpes Simples
19.
Opt Lett ; 32(8): 933-5, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17375158

RESUMO

A multimodality instrument that integrated optical or near-infrared spectroscopy into a magnetic resonance imaging (MRI) breast coil was used to perform a pilot study of image-guided spectroscopy on cancerous breast tissue. These results are believed to be the first multiwavelength spectroscopic images of breast cancer using MRI-guided constraints, and they show the cancer tumor to have high hemoglobin and water values, decreased oxygen saturation, and increased subcellular granularity. The use of frequency-domain diffuse tomography methods at many wavelengths provides the spectroscopy required for recovering maps of absorbers and scattering spectra, but the integration with MRI allows these data to be recovered on an image field that preserves high resolution and fuses the two data sets together. Integration of molecular spectroscopy into standard clinical MRI can be achieved with this approach to spectral tomography.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Hemoglobinas/análise , Oxigênio/análise , Água/análise , Adulto , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Luz Próxima ao Infravermelho
20.
Rev. med. vet. (Bogota) ; (9): 19-35, jun. 2005. ilus
Artigo em Espanhol | LILACS | ID: lil-546100

RESUMO

El ligamento cruzado anterior es el principal estabilizador de la articulación de la rodilla, su lesión produce un grado de inestabilidad que desencadena una osteoartritis degenerativa y un daño en el menisco interno en la mayoría de los casos. La ruptura del ligamento cruzado anterior (RLCA), es una de las patologías de rodilla más común en caninos. Dicha patología se encuentra relacionada con condiciones del paciente como tamaño, peso e incluso ejercicio, y también a los diversos factores biomecánicos individuales de cada animal. La RLCA, generalmente está acompañada de complicaciones como lesiones sobre los meniscos, ligamentos, inflamación y dolor. Para el tratamiento de la RLCA se han establecido una amplia variedad de técnicas Quirúrgicas, las cuales implican un abordaje total de la articulación. La técnica de la hamaca modificada permite una exitosa resolución del problema, con un abordaje mínimamente invasivo y una excelente estabilización de la articulación que permite una recuperación rápida y adecuada en paciente con ruptura de ligamento cruzado anterior en estado agudo...


Assuntos
Cães , Ligamento Cruzado Anterior , Osteoartrite , Joelho de Quadrúpedes , Especialidades Cirúrgicas
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