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1.
Cancers (Basel) ; 16(17)2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39272809

RESUMEN

Early detection of clinically significant prostate cancer (csPCa) has substantially improved with the latest PI-RADS versions. However, there is still an overdiagnosis of indolent lesions (iPCa), and radiomics has emerged as a potential solution. The aim of this systematic review is to evaluate the role of handcrafted and deep radiomics in differentiating lesions with csPCa from those with iPCa and benign lesions on prostate MRI assessed with PI-RADS v2 and/or 2.1. The literature search was conducted in PubMed, Cochrane, and Web of Science databases to select relevant studies. Quality assessment was carried out with Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2), Radiomic Quality Score (RQS), and Checklist for Artificial Intelligence in Medical Imaging (CLAIM) tools. A total of 14 studies were deemed as relevant from 411 publications. The results highlighted a good performance of handcrafted and deep radiomics methods for csPCa detection, but without significant differences compared to radiologists (PI-RADS) in the few studies in which it was assessed. Moreover, heterogeneity and restrictions were found in the studies and quality analysis, which might induce bias. Future studies should tackle these problems to encourage clinical applicability. Prospective studies and comparison with radiologists (PI-RADS) are needed to better understand its potential.

2.
J Clin Lipidol ; 18(3): e403-e412, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38368138

RESUMEN

BACKGROUND: Coronary artery calcium (CAC), thoracic aorta calcification (TAC), non-alcoholic fatty liver disease (NAFLD), and epicardial adipose tissue (EAT) are associated with atherosclerotic cardiovascular disease (ASCVD) and heart failure (HF). OBJECTIVES: We aimed to determine whether these cardiometabolic and atherosclerotic risk factors identified by non-contrast chest computed tomography (CT) are associated with HF hospitalizations in patients with LDL-C≥ 190 mg/dL. METHODS: We conducted a retrospective cohort analysis of patients with LDL-C ≥190 mg/dL, aged ≥40 years without established ASCVD or HF, who had a non-contrast chest CT within 3 years of LDL-C measurement. Ordinal CAC, ordinal TAC, EAT, and NAFLD were measured. Kaplan-Meier curves and multivariable Cox regression models were built to ascertain the association with HF hospitalization. RESULTS: We included 762 patients with median age 60 (53-68) years, 68% (n=520) female, and median LDL-C level of 203 (194-216) mg/dL. Patients were followed for 4.7 (interquartile range 2.75-6.16) years, and 107 (14%) had a HF hospitalization. Overall, 355 (47%) patients had CAC=0, 210 (28%) had TAC=0, 116 (15%) had NAFLD, and median EAT was 79 mL (49-114). Moderate-Severe CAC (log-rank p<0.001) and TAC (log-rank p=0.006) groups were associated with increased HF hospitalizations. This association persisted when considering myocardial infarction (MI) as a competing risk. NAFLD and EAT volume were not associated with HF. CONCLUSIONS: In patients without established ASCVD and LDL-C≥190 mg/dL, CAC was independently associated with increased HF hospitalizations while TAC, NAFLD, and EAT were not.


Asunto(s)
Aterosclerosis , Insuficiencia Cardíaca , Hipercolesterolemia , Tomografía Computarizada por Rayos X , Humanos , Femenino , Persona de Mediana Edad , Masculino , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/epidemiología , Anciano , Aterosclerosis/diagnóstico por imagen , Aterosclerosis/complicaciones , Hipercolesterolemia/complicaciones , Hipercolesterolemia/diagnóstico por imagen , Estudios Retrospectivos , Fenotipo , Hospitalización , Factores de Riesgo
4.
Am J Prev Cardiol ; 15: 100578, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37675408

RESUMEN

Introduction: Low-attenuation non-calcified plaque (LAP) burden and vascular inflammation by pericoronary adipose tissue (PCAT) measured from coronary CT angiography (CCTA) have shown to be predictors of cardiovascular outcomes. We aimed to investigate the relationships of cardiometabolic risk factors including lipoprotein(a) and epicardial adipose tissue (EAT) with CCTA high-risk imaging biomarkers, LAP and vascular inflammation. Methods: The patient population consisted of consecutive patients who underwent CCTA for stable chest pain and had a complete cardiometabolic panel including lipoprotein(a). Plaque, PCAT and EAT were measured from CT using semiautomated software. Elevated LAP burden and PCAT attenuation were defined as ≥4% and ≥70.5 HU, respectively. The primary clinical end-point was a composite of myocardial infarction, revascularization or cardiovascular death. Results: A total of 364 consecutive patients were included (median age 56 years, 64% female); the majority of patients were of Hispanic (60%), and the rest were of non-Hispanic Black (21%), non-Hispanic White (6%) and non-Hispanic Asian (4%) race/ethnicity. The prevalence of elevated LAP burden and PCAT attenuation was 31 and 18%, respectively, while only 8% had obstructive stenosis. There were significant differences in plaque characteristics among different racial/ethnic groups (p<0.001). Lipoprotein(a) correlated with LAP burden in Hispanic patients. Patients with elevated LAP were older, more likely to be have diabetes, hypertension, hyperlipidemia and smoke with higher CAC and EAT volume (all P<0.05). Patients with elevated LAP were more likely to develop the primary clinical outcome (p<0.001) but those with elevated PCAT were not (p=0.797). Conclusion: The prevalence of LAP and PCAT attenuation were 31 and 18%, respectively. Lipoprotein(a) levels correlated with LAP burden in Hispanic patients. Age, male sex, hypertension and hyperlipidemia increased the odds of elevated LAP, which showed prognostic significance.

5.
Circ Cardiovasc Imaging ; 16(8): e015236, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37582155

RESUMEN

BACKGROUND: Coronary artery calcium scoring (CAC) has garnered attention in the diagnostic approach to chest pain patients. However, little is known about the interplay between zero CAC, sex, race, ethnicity, and quantitative coronary plaque analysis. METHODS: We conducted a retrospective analysis from our computed tomography registry of patients with stable angina without prior myocardial infarction or revascularization undergoing coronary computed tomography angiography at Montefiore Healthcare System. Follow-up end points collected included invasive angiography, type-1 myocardial infarction, coronary revascularization, cardiovascular and all-cause death. RESULTS: A total of 2249 patients were included (66% female). The median follow-up was 5.5 years. The median age of those without CAC was 52 years (interquartile range, 44-59) and 60 years (interquartile range, 53-68) in those with CAC. Most patients were Hispanic (58%), and the rest were non-Hispanic Black (28%), non-Hispanic White (10%), and non-Hispanic Asian (5%). The majority had CAC=0 (55%). The negative predictive value of CAC=0 was 92.8%, 99.9%, and 99.9% for any plaque, obstructive coronary artery stenosis, and the composite outcome of all-cause death, myocardial infarction, or coronary revascularization, respectively. Among patients without CAC (n=1237), 89 patients (7%) had evidence of plaque on their coronary computed tomography angiography with a median low-attenuation noncalcified plaque burden of 4% (2-7). There were no significant differences in the negative predictive value for CAC=0 by sex, race, or ethnicity. Patients with ≥2 risk factors had higher odds of having plaque with zero CAC. CONCLUSIONS: In summary, no sex, race, or ethnicity differences were demonstrated in the negative predictive value of a zero CAC; however, patients with ≥2 risk factors had a higher prevalence of plaque. A small percentage (7%) of symptomatic patients undergoing coronary computed tomography angiography with zero CAC had noncalcified coronary plaque, with the implication that caution is needed for downscaling of preventive treatment in patients with zero CAC, chest pain, and multiple risk factors.


Asunto(s)
Enfermedad de la Arteria Coronaria , Infarto del Miocardio , Placa Aterosclerótica , Humanos , Femenino , Adulto , Persona de Mediana Edad , Masculino , Enfermedad de la Arteria Coronaria/diagnóstico , Angiografía Coronaria/métodos , Estudios Retrospectivos , Placa Aterosclerótica/complicaciones , Infarto del Miocardio/epidemiología , Infarto del Miocardio/etiología , Dolor en el Pecho , Factores de Riesgo , Valor Predictivo de las Pruebas , Medición de Riesgo
6.
Int J Cardiovasc Imaging ; 39(4): 863-872, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36583813

RESUMEN

PURPOSE: Virtual non-contrast (VNC) coronary artery calcium scoring (CAC) may obviate the need for traditional non-contrast (TNC) CAC. There is no data on the influence of body mass index (BMI) on VNC reliability. We aimed to evaluate the influence of BMI on VNC CAC agreement with TNC. MATERIALS AND METHODS: All patients who underwent sequential CAC and coronary CT angiography (CCTA) using spectral CT with TNC CAC > 0 between August 2020 and December 2021 were included. Agatston CAC scores were calculated manually by 2 blinded readers from VNC scans. A correction factor was calculated from the slope of the linear regression using the method of least squares and applied to the VNC scores. Bland-Altman plots and Cohen's weighted Kappa were utilized. RESULTS: We included 174 patients (57.5% female). Mean BMI was 32.6 ± 7.02 kg/m2 [BMI < 30 (39.7%); BMI 30-40 (45.4%); and BMI > 40 kg/m2 (14.9%)]. Mean TNC CAC was 177.8 ± 316.86 and mean VNC CAC after applying the correction factor 149.34 ± 296.73. The TNC value strongly correlated with VNC (r = 0.94; p < 0.0001). As BMI increased there was a progressive reduction in signal-to-noise ratio, contrast-to-noise ratio and coronary enhancement (p < 0.05). The degree of agreement between VNC and TNC CAC decreased as BMI increased (agreement = 91.79 (weighted Kappa = 0.72), 91.14 (weighted Kappa = 0.58) and 88.46% (weighted Kappa = 0.48) (all P values < 0.001) for BMI < 30; 30-40 and > 40 kg/m2, respectively). CONCLUSION: BMI has a significant influence on the accuracy of VNC CAC. VNC CAC shows substantial agreement in non-obese patients but performs poorly in BMI > 40 kg/m2. This is the first study to evaluate the influence of body mass index (BMI) on virtual non-contrast (VNC) coronary artery calcium scoring (CAC) as compared to traditional non-contrast (TNC). We retrospectively evaluated 174 patients with TNC CAC and two blinded reviewers manually calculated the VNC CAC. All cases were included without specific selection for quality. The ratio between the two directly proportional values was determined using the slope from the linear regression through the method of least squares. This correction factor of 2.65 was applied to the calcium scores obtained from VNC images. We found that VNC CAC shows substantial risk-class agreement with TNC in non-obese patients (agreement = 91.79 and weighted Kappa = 0.72) but performs poorly in BMI > 40 kg/m2 (agreement: 88.46% and weighted Kappa = 0.48). These findings show the potential use of VNC CAC to avoid additional radiation in non-obese patients. However, further research on potential improvement strategies for VNC CAC in obese patients is needed.


Asunto(s)
Calcio , Enfermedad de la Arteria Coronaria , Humanos , Femenino , Masculino , Índice de Masa Corporal , Vasos Coronarios/diagnóstico por imagen , Reproducibilidad de los Resultados , Estudios Retrospectivos , Valor Predictivo de las Pruebas , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen
7.
Circ Cardiovasc Imaging ; 15(6): e014135, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35727870

RESUMEN

BACKGROUND: Current guidelines recommend coronary artery calcium (CAC) scoring for stratification of atherosclerotic cardiovascular disease risk only in patients with borderline to intermediate risk score by the pooled cohort equation with low-density lipoprotein-cholesterol (LDL-C) of 70 to 190 mg/dL. It remains unknown if CAC or thoracic aorta calcification (TAC), detected on routine chest computed tomography, can provide further risk stratification in patients with LDL-C≥190 mg/dL. METHODS: From a multisite medical center, we retrospectively identified all patients from March 2005 to June 2021 age ≥40 years, without established atherosclerotic cardiovascular disease and LDL-C≥190 mg/dL who had non-gated non-contrast chest computed tomography within 3 years of LDL-C measurement. Ordinal CAC and TAC scores were measured by visual inspection. Kaplan-Meier curves and multivariable Cox-regression models were built to ascertain the association of CAC and TAC scores with all-cause mortality. RESULTS: We included 811 patients with median age 59 (53-68) years, 262 (32.3%) were male, and LDL-C median level was 203 (194-217) mg/dL. Patients were followed for 6.2 (3.29-9.81) years, and 109 (13.4%) died. Overall, 376 (46.4%) of patients had CAC=0 and 226 (27.9%) had TAC=0. All-cause mortality increased with any CAC and moderate to severe TAC. In a multivariate model, patients with CAC had a significantly higher mortality compared with those without CAC: mild hazard ratio (HR), 1.71 (1.03-2.83), moderate HR, 2.12 (1.14-3.94), and severe HR, 3.49 (1.94-6.27). Patients with moderate TAC (HR, 2.34 [1.19-4.59]) and those with severe TAC (HR, 3.02 [1.36-6.74]) had higher mortality than those without TAC. CONCLUSIONS: In patients without history of atherosclerotic cardiovascular disease and LDL-C≥190 mg/dL, the presence and severity of CAC and TAC are independently associated with all-cause mortality.


Asunto(s)
Enfermedades de la Aorta , Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Calcificación Vascular , Adulto , Aorta Torácica/diagnóstico por imagen , Enfermedades de la Aorta/diagnóstico por imagen , Calcio , LDL-Colesterol , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Tomografía Computarizada por Rayos X/métodos , Calcificación Vascular/complicaciones
8.
Sci Rep ; 12(1): 316, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-35013377

RESUMEN

Microwave (MWA) and radiofrequency ablation (RFA) are main ablative techniques for hepatocellular carcinoma (HCC) and colorectal liver metastasis (MT). This randomized phase 2 clinical trial compares the effectiveness of MWA and RFA as well as morphology of corresponding ablation zones. HCC and MT patients with 1.5-4 cm tumors, suitable for ablation, were randomized into MWA or RFA Groups. The primary endpoint was short-to-long diameter ratio of ablation zone (SLR). Primary technical success (TS) and a cumulative local tumor progression (LTP) after a median 2-year follow-up were compared. Between June 2015 and April 2020, 82 patients were randomly assigned (41 patients per group). For the per-protocol analysis, five patients were excluded. MWA created larger ablation zones than RFA (p = 0.036) although without differences in SLR (0.5 for both groups, p = 0.229). The TS was achieved in 98% (46/47) and 90% (45/50) (p = 0.108), and LTP was observed in 21% (10/47) vs. 12% (6/50) (OR 1.9 [95% CI 0.66-5.3], p = 0.238) of tumors in MWA vs. RFA Group, respectively. Major complications were found in 5 cases (11%) vs. 2 cases (4%), without statistical significance. MWA and RFA show similar SLR, effectiveness and safety in liver tumors between 1.5 and 4 cm.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Neoplasias Colorrectales/patología , Neoplasias Hepáticas/cirugía , Microondas/uso terapéutico , Ablación por Radiofrecuencia , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Masculino , Microondas/efectos adversos , Persona de Mediana Edad , Estudios Prospectivos , Ablación por Radiofrecuencia/efectos adversos , Método Simple Ciego , España , Factores de Tiempo , Resultado del Tratamiento , Carga Tumoral
9.
Rev. Asoc. Argent. Ortop. Traumatol ; 86(4) (Nro Esp - ACARO Asociación Argentina para el Estudio de la Cadera y Rodilla): 475-482, 2021.
Artículo en Español | LILACS, BINACIS | ID: biblio-1353948

RESUMEN

Introducción: El diseño del implante femoral es imprescindible para su adaptación a los distintos tipos de canales. El objetivo del estudio fue comparar la adaptabilidad del implante y el tipo de contacto de los tallos femorales planos de segunda generación. Materiales y Métodos: Se analizó a los pacientes sometidos a un reemplazo total de cadera bilateral en nuestra institución, entre 2007 y 2020, a quienes se les colocó un tallo de primera generación (Accolade TMZF) en una cadera y de segunda generación (Accolade II) en la contralateral. Se estudiaron las variables demográficas, la adaptación y el llenado del canal. Se analizó el Harris Hip Score modificado y el índice WOMAC. Resultados:Se incluyó a 42 pacientes (84 casos).En el grupo 1 (Accolade TMZF), la ocupación del canal fue del 81% y, en el grupo 2 (Accolade II), del 84%. En el grupo 1, el contacto fue tipo 1 (60%), tipo 2 (16%) y tipo 3 (24%). En el grupo 2, fue tipo 1 (88%), tipo 2 (7%) y tipo 3 (5%). El Harris Hip Score modificado para el grupo 1 fue 88 y, para el grupo 2, 87,5. El puntaje WOMAC para el grupo 1 fue 2,5 y, para el grupo 2, de 3. Conclusión: La adaptabilidad del implante es fundamental para la estabilidad primaria y su osteointegración/fijación biológica. En nuestra muestra, es más precisa con tallos de segunda generación debido a las modificaciones del diseño. Nivel de Evidencia: IV


Introduction: The design of the femoral implant is essential for its adaptation to the different types of femoral canals. The objective of this study is to describe the adaptability of the implant and the type of fixation (fill and fit) of second-generation flat femoral stems compared to first-generation femoral stems. Materials and Methods: We described the radiological characteristics of patients who had undergone bilateral total hip replacement between 2007 and 2020 in our institution with both a first-generation Accolade TMZF (Stryker Orthopedics) and a second-generation Accolade II (Stryker Orthopedics) flat cementless femoral implant. Demographic variables, adaptation, and canal filling were studied. The modified Harris Hip Score and the WOMAC index were analyzed. Results: Forty-two patients (84 cases) were included in the sample. In group 1 (Accolade TMZF) we obtained an average canal fill of 81% and in group 2 (Accolade II), we obtained an average of 84%. In group 1, the type of fixation (fit) was type 1 (60%), type 2 (16%) and type 3 (24%). In group 2, it was type 1 (88%), type 2 (7%) and type 3 (5%). The modified Harris Hip Score for group 1 was 88 and, for group 2, 87.5. The WOMAC score for group 1 was 2.5 and for group 2 it was 3. Conclusion: The adaptability of the implant is essential for primary stability and its osseointegration/biological fixation. This adaptability is more precise with second-generation flat femoral stems. Level of Evidence: IV


Asunto(s)
Persona de Mediana Edad , Anciano , Epidemiología Descriptiva , Estudios Retrospectivos , Oseointegración , Artroplastia de Reemplazo de Cadera , Fémur
10.
JBJS Case Connect ; 8(2): e31, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29794486

RESUMEN

CASE: Following an insidious onset of symptoms, a 29-year-old man who had no risk factors for tuberculosis was diagnosed with tuberculosis of the iliac crest. The red flag in this case was the patient's progressive deterioration despite a variety of antibiotic regimens. Histopathologic demonstration of necrotic granulomatous inflammation and a positive culture led to the diagnosis. A combination of surgery and antitubercular-drug therapy resulted in clinical recovery. CONCLUSION: Iliac crest tuberculosis represents <1% of all skeletal tuberculosis cases. Even in the absence of classic symptoms and risk factors, orthopaedic surgeons should maintain a low threshold for tuberculosis in the differential diagnosis.


Asunto(s)
Ilion , Tuberculosis Osteoarticular , Adulto , Antituberculosos/administración & dosificación , Antituberculosos/uso terapéutico , Hospitalización , Humanos , Ilion/diagnóstico por imagen , Ilion/microbiología , Ilion/patología , Ilion/cirugía , Masculino
13.
Neotrop. ichthyol ; 9(3): 593-599, 2011. graf, mapas
Artículo en Inglés | LILACS | ID: lil-600888

RESUMEN

The population structure and reproductive condition of the Sinaloa cichlid Cichlasoma beani from samples obtained from June 2000 to July 2001 were determined. Samples in the first week each month from the largest trader of tilapia in the Aguamilpa Reservoir in Mexico and were caught in gillnets (9.6 and 11.4 cm stretch-mesh size). Of 596 specimens, there were 427 males and 169 females; monthly sex ratio, frequency of lengths by the multinomial distribution, timing of reproduction, condition index, and size at first maturity was determined. Differences in the sex ratio and monthly totals were significant, favoring males, except for September 2000 and March 2001. From one (August 2000) to three modal groups (July 2000 and June 2001) were identified by size. There were no significant differences in standard length weight relationships by sex, which indicated that a shared model for both genders is appropriate, and isometric growth was detected. Based on the proportion of mature and partially matures fish, the main reproductive period was April through June; size at first maturity was 18.9 cm. Water temperature was not significantly related to the percentage of mature and partially matures Sinaloa cichlids or spawning. These findings provide information for regulating the Cichlasoma beani fishery in this region such minimum legal size and non-fishing period.


Se determinó la estructura poblacional y condición reproductiva del cíclido de Sinaloa Cichlasoma beani desde junio de 2000 a julio de 2001. Las muestras se obtuvieron de la captura comercial de tilapia en el embalse de Aguamilpa, México durante la primera semana de cada mes. Los especímenes se capturaron con redes de enmalle (9,6 y 11,4 cm de tamaño de malla). De los 596 organismos recolectados, 427 fueron machos y 169 hembras. Se determinó la proporción de sexos mensual, grupos modales de tallas a través de una distribución multinomial, época reproductiva, índice de condición y talla de primera madurez. Se encontraron diferencias significativas en la proporción de sexos total y mensual favoreciendo a los machos, excepto en septiembre de 2000 y marzo de 2001. Se identificaron desde uno (agosto de 2000) hasta tres grupos modales de tallas (julio de 2000 y junio de 2001). No se encontraron diferencias significativas en la relación longitud patrón - peso total por sexo, lo que sugiere que el uso de un solo modelo para ambos sexos es adecuado, presentando crecimiento de tipo isométrico. Con base en la proporción de organismos parcialmente maduros y maduros, el pico principal de reproducción fue desde abril hasta junio; la talla de primera madurez fue de 18,9 cm. No se encontró una correlación significativa entre la temperatura del agua y el porcentaje de individuos parcialmente maduros, maduros o desovados. La información generada es útil para la regulación de la pesca de Cichlasoma beani en esta región, sugiriendo una talla mínima legal de captura y un periodo de veda adecuado para la especie.


Asunto(s)
Animales , Perciformes , Peces/crecimiento & desarrollo , Maduración Sexual
14.
Rev. biol. trop ; Rev. biol. trop;58(4): 1577-1586, dic. 2010. graf, tab
Artículo en Inglés | LILACS | ID: lil-638021

RESUMEN

Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2 413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL) and total weight (TW) were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L ∞, k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (b<3). Significant differences were found between SL/TW model for the sexes, suggesting separate models for males and females. Results indicate that there are no differences in growth rates between sexes; the proposed parameters were L∞=43.33cm standard length, k=0.36/year and t0=-0.43years. Natural and fishing mortality coefficients were 0.83/year and 1.10/year, respectively. The estimated exploitation rate (0.57/year) suggested that during the study period the fishery showed signs of overfishing. Blue tilapia reproduces year-round; the highest activity occurs from January through May and size of first maturity was 23cm SL. We conclude that it is necessary to establish a minimum catch size in this reservoir based on the reproductive behavior of this species. Rev. Biol. Trop. 58 (4): 1577-1586. Epub 2010 December 01.


Los parámetros de crecimiento, reproducción y mortalidad de Oreochormis aureus en el embalse de Aguamilpa, México fueron determinados. Un total de 2 413 organismos se recolectaron entre julio de 2000 y junio de 2001, de los cuales 1 371 fueron machos y 1 042 hembras. Se analizó la relación longitud estándar (LE) y peso total (PT) mediante modelos potenciales. Los parámetros de crecimiento de la ecuación de von Bertalanffy fueron estimados usando la distribución de frecuencia de tallas con ayuda del programa ELEFAN-I. Finalmente se determinó el ciclo reproductivo, talla de primera madurez y fecundidad. Los resultados indicaron que tanto hembras como machos presentaron crecimiento alométrico negativo. Se encontraron diferencias significativas entre hembras y machos para la relación LE- PT sugiriendo modelos separados por sexo. No existieron diferencias significativas en el crecimiento por sexo y la tasa de explotación estimada (0.57/año) sugiere que la pesquería durante el periodo de estudio mostró signos de sobreexplotación. La tilapia azul se reproduce a lo largo del año con mayor intensidad entre enero y mayo. Por lo tanto se concluye que es necesario establecer una talla mínima de captura con base en el comportamiento reproductivo de la especie.


Asunto(s)
Animales , Femenino , Masculino , Longevidad , Reproducción/fisiología , Maduración Sexual/fisiología , Tilapia/fisiología , Explotaciones Pesqueras , México , Estaciones del Año , Tilapia/crecimiento & desarrollo
15.
Rev Biol Trop ; 58(4): 1577-86, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21247004

RESUMEN

Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL) and total weight (TW) were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L infinity k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (b < 3). Significant differences were found between SL/TW model for the sexes, suggesting separate models for males and females. Results indicate that there are no differences in growth rates between sexes; the proposed parameters were L infinity = 43.33 cm standard length, k = 0.36/year and t0 = -0.43 years. Natural and fishing mortality coefficients were 0.83/year and 1.10/year, respectively. The estimated exploitation rate (0.57/year) suggested that during the study period the fishery showed signs of overfishing. Blue tilapia reproduces year-round; the highest activity occurs from January through May and size of first maturity was 23 cm SL. We conclude that it is necessary to establish a minimum catch size in this reservoir based on the reproductive behavior of this species.


Asunto(s)
Longevidad , Reproducción/fisiología , Maduración Sexual/fisiología , Tilapia/fisiología , Animales , Femenino , Explotaciones Pesqueras , Masculino , México , Estaciones del Año , Tilapia/crecimiento & desarrollo
16.
Eur J Echocardiogr ; 11(5): E18, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20008328

RESUMEN

Left atrial wall haematoma is a very uncommon entity, associated mainly to cardiac surgery, interventional procedures, or trauma. Spontaneous cases are supposed to be associated with left atrial wall pathology. We present a case of a 53-year-old male who was admitted for prolonged chest pain, with transthoracic and transesophagic echocardiography documentation of a left atrial mass in close proximity to a mitral annular calcification. Tissue characterization with cardiac magnetic resonance suggested the aetiology of the mass, which was confirmed histologically.


Asunto(s)
Calcinosis/patología , Atrios Cardíacos/patología , Hematoma/patología , Válvula Mitral/patología , Calcinosis/diagnóstico por imagen , Calcinosis/cirugía , Dolor en el Pecho , Ecocardiografía , Ecocardiografía Transesofágica , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/cirugía , Hematoma/diagnóstico por imagen , Hematoma/cirugía , Humanos , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/cirugía , Factores de Tiempo
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