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1.
Endocrine ; 86(2): 692-698, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38874828

RESUMEN

PURPOSE: Thyroid lobectomy (TL) is an appropriate treatment for up to 4 cm intrathyroidal differentiated thyroid cancer (DTC). There is scarce data regarding TL outside first-world centers. Our aim is to report a cohort of patients with DTC treated with TL in Chile. METHODS: We included DTC patients treated with TL, followed for at least 6 months, characterized their clinicopathological features and classified their risk of recurrence and response to treatment. RESULTS: Eighty-two patients followed for a median of 2.3 years (0.5-7.0). Seventy-three (89%) patients had papillary, 8 (9.8%) follicular and 1 (1.2%) high-grade DTC. The risk of recurrence was low in 56 (68.3%) and intermediate in 26 (31.7%). Eight (9.8%) patients required early completion thyroidectomy and radioiodine. At last follow-up, 52 (70.3%) had excellent, 19 (25.7%) had indeterminate, and 1 (1.4%) had structural incomplete response. CONCLUSION: In a developing country, TL is an adequate option for appropriately selected DTC patients.


Asunto(s)
Neoplasias de la Tiroides , Tiroidectomía , Humanos , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/radioterapia , Femenino , Masculino , Persona de Mediana Edad , Tiroidectomía/métodos , Chile/epidemiología , Adulto , Anciano , Resultado del Tratamiento , Centros de Atención Terciaria , Recurrencia Local de Neoplasia/epidemiología , Adulto Joven , Radioisótopos de Yodo/uso terapéutico , Estudios de Seguimiento , Adenocarcinoma Folicular/cirugía , Adenocarcinoma Folicular/patología , Adenocarcinoma Folicular/radioterapia , Adolescente , Estudios Retrospectivos , Carcinoma Papilar/cirugía , Carcinoma Papilar/patología
2.
Rev. méd. Chile ; 148(5): 697-701, mayo 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1139355

RESUMEN

ABSTRACT Hyperthyroidism can induce elevation in several liver function tests including aminotransferases, alkaline phosphatases and, less frequently, serum bilirubin. These alterations are usually mild and asymptomatic. We report a 26 year-old male presenting with palpitations, progressive jaundice, choluria and generalized itching. Laboratory tests were compatible with hyperthyroidism and a mild elevation of bilirubin, alkaline phosphatases and gamma glutamyl transpeptidase. A liver biopsy showed portal hepatitis with canalicular cholestasis. The patient was treated temporarily with glucocorticoids, cholestyramine and betablockade. Thereafter, he was treated with radioactive iodine, after which serum bilirubin decreased steadily until normalization in ten weeks.


El hipertiroidismo puede producir elevación de aminotransferasas, fosfatasas alcalinas y, menos frecuentemente, de bilirrubina sérica. Habitualmente, estas alteraciones son leves y asintomáticas. Reportamos un hombre de 26 años con hipertiroidismo secundario a enfermedad de Basedow-Graves, que debutó con un cuadro colestásico, inicialmente estudiado por sospecha de patología hepática autoinmune que incluyó biopsia hepática. Posteriormente, se diagnosticó hipertiroidismo que fue tratado con glucocorticoides, colestiramina y beta bloqueo como puente a terapia definitiva con radioyodo. La evolución mostró disminución progresiva hasta la normalización de bilirrubina sérica.


Asunto(s)
Humanos , Masculino , Adulto , Enfermedad de Graves/complicaciones , Colestasis/diagnóstico , Colestasis/etiología , Hipertiroidismo/complicaciones
3.
Braz J Microbiol ; 51(3): 949-956, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32144691

RESUMEN

The growing demand of consumers for synthetic chemical-free foods has increased the search for natural preservatives such as bacteriocins and bacteriocin-like inhibitory substances (BLIS) to give them adequate microbiological safety, sensory characteristics, and shelf life. In this study, the antimicrobial activity of BLIS produced by Pediococcus pentosaceus ATCC 43200 was compared with that of nisin. Lactobacillus sakei ATCC 15521, Listeria seeligeri NCTC 11289, Enterococcus En2052 and En2865, and Listeria monocytogenes CECT 934 and NADC 2045 exhibited larger inhibition halos in BLIS-treated than in Nisaplin-treated samples, unlike Listeria innocua NCTC 11288. In artificially contaminated ready-to-eat pork ham, BLIS was effective in inhibiting the growth of L. seeligeri NCTC 11289 for 6 days (counts from 1.74 to 0.00 log CFU/g) and ensured lower weight loss (2.7%) and lipid peroxidation (0.63 mg MDA/kg) of samples compared with the control (3.0%; 1.25 mg MDA/kg). At the same time, coloration of ham samples in terms of luminosity, redness, and yellowness as well as discoloration throughout cold storage was not influenced by BLIS or Nisaplin taken as a control. These results suggest the potential use of P. pentosaceus BLIS as a biopreservative in meat and other food processing industries.


Asunto(s)
Antibacterianos/farmacología , Bacteriocinas/farmacología , Conservantes de Alimentos/farmacología , Listeria/efectos de los fármacos , Pediococcus pentosaceus/metabolismo , Carne de Cerdo/microbiología , Animales , Recuento de Colonia Microbiana , Microbiología de Alimentos , Almacenamiento de Alimentos , Listeria/crecimiento & desarrollo , Nisina/farmacología , Carne de Cerdo/análisis
4.
Rev Med Chil ; 148(5): 697-701, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-33399764

RESUMEN

Hyperthyroidism can induce elevation in several liver function tests including aminotransferases, alkaline phosphatases and, less frequently, serum bilirubin. These alterations are usually mild and asymptomatic. We report a 26 year-old male presenting with palpitations, progressive jaundice, choluria and generalized itching. Laboratory tests were compatible with hyperthyroidism and a mild elevation of bilirubin, alkaline phosphatases and gamma glutamyl transpeptidase. A liver biopsy showed portal hepatitis with canalicular cholestasis. The patient was treated temporarily with glucocorticoids, cholestyramine and betablockade. Thereafter, he was treated with radioactive iodine, after which serum bilirubin decreased steadily until normalization in ten weeks.


Asunto(s)
Colestasis , Enfermedad de Graves , Hipertiroidismo , Adulto , Colestasis/diagnóstico , Colestasis/etiología , Enfermedad de Graves/complicaciones , Humanos , Hipertiroidismo/complicaciones , Masculino
5.
Arch. endocrinol. metab. (Online) ; 63(3): 293-299, May-June 2019. tab
Artículo en Inglés | LILACS | ID: biblio-1011157

RESUMEN

ABSTRACT Objective Our objective was to evaluate the trend of antithyroglobulin antibodies (TgAb) during follow-up of patients with differentiated thyroid cancer (DTC) treated without RAI, as well as their role in the risk of recurrence. Subjects and methods This was a prospective, descriptive study. A total of 152 consecutive patients with DTC treated in a single institution undergoing total thyroidectomy without RAI and followed for a median of 2.3 years (0.5-10.3) were divided in two groups: TgAb(-) (n = 111) and TgAb(+) (n = 41). Patients were classified according to AJCC 7th and 8th editions, as well as to their risk of recurrence and response to treatment categories. Results Both groups, TgAb(-) and TgAb(+), were similar regarding patient and tumor characteristics. At the end of follow-up, 90 (59.2%), 57 (37.5%), 3 (2%) and 2 (1.3%) patients achieved excellent, indeterminate, biochemically incomplete and structurally incomplete response, respectively. The risk of structural recurrence was similar in both groups (TgAb[-] 0.9% vs. TgAb[+] 2.4%, p = 0.46). In the TgAb(+) group, TgAb became negative in 10 (24.4%), decreased ≥ 50% without negativization in 25 (60.9%), decreased < 50% in 4 (9.8%) and remained stable or increased in 2 (4.9%) cases. The only incomplete structural response had increasing TgAb during follow-up. Conclusions In properly selected patients with DTC, TgAb concentration immediately after total thyroidectomy should not mandate RAI ablation, and their trend during follow-up may impact the risk of recurrence.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Autoanticuerpos/sangre , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/terapia , Radioisótopos de Yodo/administración & dosificación , Tiroidectomía , Neoplasias de la Tiroides/radioterapia , Estudios Prospectivos , Estudios de Seguimiento , Resultado del Tratamiento
6.
Arch Endocrinol Metab ; 63(3): 293-299, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31038590

RESUMEN

OBJECTIVE: Our objective was to evaluate the trend of antithyroglobulin antibodies (TgAb) during follow-up of patients with differentiated thyroid cancer (DTC) treated without RAI, as well as their role in the risk of recurrence. SUBJECTS AND METHODS: This was a prospective, descriptive study. A total of 152 consecutive patients with DTC treated in a single institution undergoing total thyroidectomy without RAI and followed for a median of 2.3 years (0.5-10.3) were divided in two groups: TgAb(-) (n = 111) and TgAb(+) (n = 41). Patients were classified according to AJCC 7th and 8th editions, as well as to their risk of recurrence and response to treatment categories. RESULTS: Both groups, TgAb(-) and TgAb(+), were similar regarding patient and tumor characteristics. At the end of follow-up, 90 (59.2%), 57 (37.5%), 3 (2%) and 2 (1.3%) patients achieved excellent, indeterminate, biochemically incomplete and structurally incomplete response, respectively. The risk of structural recurrence was similar in both groups (TgAb[-] 0.9% vs. TgAb[+] 2.4%, p = 0.46). In the TgAb(+) group, TgAb became negative in 10 (24.4%), decreased ≥ 50% without negativization in 25 (60.9%), decreased < 50% in 4 (9.8%) and remained stable or increased in 2 (4.9%) cases. The only incomplete structural response had increasing TgAb during follow-up. CONCLUSIONS: In properly selected patients with DTC, TgAb concentration immediately after total thyroidectomy should not mandate RAI ablation, and their trend during follow-up may impact the risk of recurrence.


Asunto(s)
Autoanticuerpos/sangre , Radioisótopos de Yodo/administración & dosificación , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias de la Tiroides/radioterapia , Tiroidectomía , Resultado del Tratamiento , Adulto Joven
7.
Arch Endocrinol Metab ; 62(1): 6-13, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29694628

RESUMEN

Objective We aimed to describe the presentation of papillary microcarcinoma (PTMC) and identify the clinical and histological features associated with persistence/recurrence in a Latin American cohort. Subjects and methods Retrospective study of PTMC patients who underwent total thyroidectomy, with or without radioactive iodine (RAI), and who were followed for at least 2 years. Risk of recurrence was estimated with ATA 2009 and 2015 classifications, and risk of mortality with 7th and 8th AJCC/TNM systems. Clinical data obtained during follow-up were used to detect structural and biochemical persistence/recurrence. Results We included 209 patients, predominantly female (90%), 44.5 ± 12.6 years old, 183 (88%) received RAI (90.4 ± 44.2 mCi), followed-up for a median of 4.4 years (range 2.0-7.8). The 7th and 8th AJCC/TNM system classified 89% and 95.2% of the patients as stage I, respectively. ATA 2009 and ATA 2015 classified 70.8% and 78.5% of the patients as low risk, respectively. Fifteen (7%) patients had persistence/recurrence during follow-up. In multivariate analysis, only lymph node metastasis was associated with persistence/recurrence (coefficient beta 4.0, p = 0.016; 95% CI 1.3-12.9). There were no PTMC related deaths. Conclusions Our series found no mortality and low rate of persistence/recurrence associated with PTMC. Lymph node metastasis was the only feature associated with recurrence in multivariate analysis. The updated ATA 2015 and 8th AJCC/TNM systems classified more PTMCs than previous classifications as low risk of recurrence and mortality, respectively.


Asunto(s)
Carcinoma Papilar/cirugía , Recurrencia Local de Neoplasia , Neoplasias de la Tiroides/cirugía , Adulto , Carcinoma Papilar/radioterapia , Estudios de Cohortes , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Neoplasias de la Tiroides/radioterapia , Tiroidectomía
8.
Arch. endocrinol. metab. (Online) ; 62(1): 6-13, Jan.-Feb. 2018. tab
Artículo en Inglés | LILACS | ID: biblio-887624

RESUMEN

ABSTRACT Objective We aimed to describe the presentation of papillary microcarcinoma (PTMC) and identify the clinical and histological features associated with persistence/recurrence in a Latin American cohort. Subjects and methods Retrospective study of PTMC patients who underwent total thyroidectomy, with or without radioactive iodine (RAI), and who were followed for at least 2 years. Risk of recurrence was estimated with ATA 2009 and 2015 classifications, and risk of mortality with 7th and 8th AJCC/TNM systems. Clinical data obtained during follow-up were used to detect structural and biochemical persistence/recurrence. Results We included 209 patients, predominantly female (90%), 44.5 ± 12.6 years old, 183 (88%) received RAI (90.4 ± 44.2 mCi), followed-up for a median of 4.4 years (range 2.0-7.8). The 7th and 8th AJCC/TNM system classified 89% and 95.2% of the patients as stage I, respectively. ATA 2009 and ATA 2015 classified 70.8% and 78.5% of the patients as low risk, respectively. Fifteen (7%) patients had persistence/recurrence during follow-up. In multivariate analysis, only lymph node metastasis was associated with persistence/recurrence (coefficient beta 4.0, p = 0.016; 95% CI 1.3-12.9). There were no PTMC related deaths. Conclusions Our series found no mortality and low rate of persistence/recurrence associated with PTMC. Lymph node metastasis was the only feature associated with recurrence in multivariate analysis. The updated ATA 2015 and 8th AJCC/TNM systems classified more PTMCs than previous classifications as low risk of recurrence and mortality, respectively.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Neoplasias de la Tiroides/cirugía , Carcinoma Papilar/cirugía , Recurrencia Local de Neoplasia , Pronóstico , Tiroidectomía , Neoplasias de la Tiroides/radioterapia , Carcinoma Papilar/radioterapia , Estudios Retrospectivos , Factores de Riesgo , Estudios de Cohortes , Terapia Combinada
9.
J Ultrasound Med ; 36(11): 2299-2307, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28543974

RESUMEN

OBJECTIVES: Follow-up of patients with low-risk differentiated thyroid cancer treated with total thyroidectomy and radioiodine requires neck sonography and thyroglobulin (Tg). The need to stimulate Tg is controversial. The goal of this study was to compare the diagnostic performances of sonography plus suppressed or stimulated Tg in low-risk thyroid cancer. METHODS: After total thyroidectomy and radioiodine, patients with low-risk thyroid cancer were retrospectively identified as having structural or biochemical persistence/recurrence. We compared the diagnostic performance of suppressed and stimulated Tg to detect persistence/recurrence. RESULTS: We included 148 patients with low-risk thyroid cancer who were followed for a median of 3.7 years. Persistence/recurrence was found in 8 patients (5.4%; 5 structural disease and 3 biochemical disease). Thyroglobulin was not stimulated in 72 patients (group 1) and stimulated in 76 (group 2). In group 1, 5 patients (6.9%) had structural neck persistence/recurrence (3 with suppressed Tg ≥ 1 ng/mL and 2 with suppressed Tg < 1 ng/mL). Four patients underwent surgery, and 1 was surveilled. All 5 patients had suppressed Tg lower than 1 ng/mL at the end of follow-up. In group 2, stimulated Tg did not identify additional cases of structural persistence/recurrence but classified 3 patients (3.9%) as having biochemical persistence/recurrence. One patient received a second dose of radioiodine, and the other 2 were surveilled; all were without disease at the end of follow-up. Suppressed and stimulated Tg had negative predictive values for persistence/recurrence of 97% and 100%, respectively. CONCLUSIONS: In low-risk thyroid cancer treated with total thyroidectomy and radioiodine, sonography and suppressed or stimulated Tg have similar negative predictive values for persistence/recurrence. Importantly, the coexistence of negative sonographic findings and suppressed Tg lower than 1 ng/mL makes the addition of stimulated Tg unlikely to identify clinically important disease.


Asunto(s)
Radioisótopos de Yodo/uso terapéutico , Recurrencia Local de Neoplasia/sangre , Recurrencia Local de Neoplasia/diagnóstico por imagen , Tiroglobulina/sangre , Neoplasias de la Tiroides/terapia , Ultrasonografía/métodos , Adulto , Braquiterapia/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Cuello/diagnóstico por imagen , Estudios Retrospectivos , Neoplasias de la Tiroides/sangre , Tiroidectomía
10.
Int J Endocrinol ; 2016: 2586512, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27867395

RESUMEN

Context. Radioiodine (RAI) administration has adverse effects in patients treated for thyroid cancer (DTC), but there is scarce information regarding their intensity and duration. Objective. To evaluate frequency and intensity of early and late RAI-related symptoms in patients with DTC. Design. Observational prospective study. Patients. DTC patients who underwent thyroidectomy, with or without RAI. Measurements. Patients answered 2 surveys: (1) from 0 to 6 months and (2) between 6 and 18 months after initial treatment. Results. 110 patients answered the first survey and 61 both. Nearly 80 percent received RAI. Among early symptoms, periorbital edema, excessive tearing, salivary gland disturbances, dry mouth, taste disorders, and nausea were more frequent and intense among RAI patients. Regarding late symptoms, periorbital edema, salivary gland pain and swelling, and dry mouth were more frequent and intense in RAI patients. Frequency and intensity of adverse effects were not different between low and high RAI doses (50 versus ≥100 mCi). Conclusion. RAI-related symptoms are frequent and usually persist after 6 months of administration, even when low doses are given. This finding must be considered when deciding RAI administration, especially in low risk patients, among whom RAI benefit is controversial.

11.
An. acad. bras. ciênc ; 83(4): 1207-1220, Dec. 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-607442

RESUMEN

Using numerical modeling, this work estimates sediment dispersion patterns caused by the incidence of waves in five distinct coastline contours of the Jequitinhonha River delta plain during the Late Holocene. For this study, a wave cliate odel based on the construction of ave refraction diagras relative to the current boundary conditions as defined and assumed to be valid for the five coastlines. Numerical modeling from the refraction diagrams was carried out considering the angle of incidence and wave height along the coastline. This work has allowed us to reproduce past and current patterns of net longshore sediment drift defined by a conceptual model developed from the integration of sediment cores, aerial photograph interpretation, C14 datings and geomorphic indicators of longshore drift. These results show that, on average, current wave conditions in the east-northeastern Brazilian region seem to have remained characteristically the same from approximately 5100 years BP until the present time. This type of information can be important when attempting to simulate possible future situations in terms of the long-term general behavior of the east-northeastern Brazilian coastal region.


O presente trabalho apresenta uma estimativa, por modelagem numérica, dos padrões de dispersão de sedimentos causados pela incidência de ondas em cinco distintos contornos de linhas de costa da planície deltaica do Rio Jequitinhonha durante o Holoceno Tardio. Para isso, um modelo de clima de ondas baseado na construção de diagramas de refração de onda, em função das condições de contorno atuais, foi definido e assumido ser válido para as cinco linhas de costa. A modelagem numérica, a partir dos diagramas de refração, foi feita considerando o ângulo de aproximação e a altura da onda ao longo da linha de costa. O trabalho permitiu reproduzir os padrões pretéritos e atuais da deriva litorânea efetiva de sedimentos, definidos por um modelo conceitual desenvolvido a partir da integração de testemunhos de sedimentos, interpretação de fotos aéreas e datações de C14, bem como por indicadores geomórficos de deriva. Estes resultados mostram que, em média, em relação à região leste-nordeste brasileira as condições de onda atuais parecem ter permanecido com as mesmas características desde aproximadamente 5.100 anos A.P. até o tempo atual. Esse tipo de informação pode ser importante para tentativas de simulação de possíveis situações futuras em termos do comportamento genérico de longa duração das regiões costeiras leste-nordeste brasileira.

12.
Steroids ; 76(14): 1575-81, 2011 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-21996535

RESUMEN

Metabolic syndrome (MetS) may have increased cortisol (F) production caused by 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) in liver and adipose tissue and/or by HPA axis dysregulation. F is then mainly metabolized by liver reductases into inactive tetrahydrometabolites (THMs). We measured THM levels in patients with or without MetS and evaluate the correlation between THMs and anthropometric and biochemical parameters. We recruited 221 subjects, of whom 130 had MetS by ATP III. We evaluated F, cortisone (E), adipokines, glucose, insulin and lipid profiles as well as urinary (24h) F, E and THM levels. ß Cell function was estimated by the HOMA Calculator. We observed that patients with MetS showed higher levels of THMs, HOMA-IR and leptin and lower levels of adiponectin and HOMA-ß but no differences in F and E in plasma or urine. THM was associated with weight (r = +0.44, p<0.001), waist circumference (r = +0.38, p<0.01), glycemia (r = +0.37, p<0.01), and triglycerides (r = +0.18, p=0.06) and negatively correlated with adiponectin (r = -0.36, p<0.001), HOMA-ß (r = -0.21, p<0.001) and HDL (r = -0.29, p<0.01). In a logistic regression model, THM levels were associated with hypertension, hyperglycemia and dyslipidemia. We conclude that MetS is associated with increased urinary THMs but not with F and E levels in plasma or urine. Increased levels of THM, reflecting the daily cortisol production subsequently metabolized, are correlated with hypoadiponectinemia, hypertension, dyslipidemia, insulin resistance and ß cell dysfunction. A subtle increased in glucocorticoid production may further account for the phenotypic and biochemical similarities observed in central obesity and Cushing's syndrome.


Asunto(s)
Adiponectina/metabolismo , Glucocorticoides/metabolismo , Glucocorticoides/orina , Resistencia a la Insulina , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Síndrome Metabólico/metabolismo , Adulto , Femenino , Humanos , Metabolismo de los Lípidos , Masculino , Síndrome Metabólico/orina , Persona de Mediana Edad , Obesidad/metabolismo , Obesidad/orina
13.
Ecotoxicol Environ Saf ; 74(3): 403-15, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21074854

RESUMEN

Camamu Bay, an Environmentally Protected Area, may be affected by the pressures of tourism and oil exploration in the adjacent continental platform. The current quality of the mangrove sediments was evaluated by porewater bioassays using embryos of Crassostrea rhizophorae and by an analysis of benthic macrofauna and its relationships with organic compounds, trace metals and bioavailability. Porewater toxicity varied from low to moderate in the majority of the samples, and polychaetes dominated the benthos. The Grande Island sampling station (Station 1) presented more sandy sediments, differentiated macrobenthic assemblages and the highest metal concentrations in relation to other stations and guideline values, and it was the only station that indicated a possible bioavailability of metals. The origin of the metals (mainly barium) is most likely associated with the barite ore deposits located in the Grande and Pequena islands. These results may be useful for future assessment of the impact of oil exploration in the coastal region.


Asunto(s)
Crassostrea/efectos de los fármacos , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Rhizophoraceae , Contaminantes Químicos del Agua/toxicidad , Alcanos/análisis , Alcanos/toxicidad , Animales , Biodiversidad , Brasil , Crassostrea/embriología , Larva/efectos de los fármacos , Metales Pesados/análisis , Metales Pesados/toxicidad , Análisis Multivariante , Petróleo/análisis , Petróleo/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Medición de Riesgo , Agua de Mar/química , Contaminantes Químicos del Agua/análisis
14.
Mar Pollut Bull ; 60(3): 474-81, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20044099

RESUMEN

Camamu Bay (Bahia, Brazil) is an Environmental Protected Area with mangroves of economic and ecological importance. The objective of this study was to elucidate, through the distribution of the benthic macrofauna and its relationships with trace metals and bioavailabilty, if the current quality of the mangrove sediments of Camamu Bay is acceptable for the protection of aquatic life. Seven sampling stations were selected as representative of the meso-littoral region of Camamu Bay. It was found 581 macrobenthic organisms distributed in 38 species. The highest values of metals occurred at stations located in areas that influenced by barite extraction, while the lowest concentrations were found in areas with relatively lower anthropogenic influence. Analysis of acid volatile sulphide and simultaneously extracted metals showed the occurrence of the ratio SEM/AVS >1, indicative of possible bioavailability of metals, at only one station. The results suggested that Camamu Bay is a nearly pristine area.


Asunto(s)
Sedimentos Geológicos/química , Metales/análisis , Contaminantes Químicos del Agua/análisis , Animales , Biodiversidad , Bivalvos/crecimiento & desarrollo , Brasil , Ecosistema , Monitoreo del Ambiente , Peces/crecimiento & desarrollo , Gastrópodos/crecimiento & desarrollo , Insectos/crecimiento & desarrollo , Poliquetos/crecimiento & desarrollo , Dinámica Poblacional , Pepinos de Mar/crecimiento & desarrollo
15.
An Acad Bras Cienc ; 80(1): 205-14, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18345388

RESUMEN

This paper shows that the location of the shoreface bank reefs along the northeastern and eastern coasts of Brazil, in a first order approximation, seem to be controlled by the deficit of sediment in the coastal system. The sediment transport pattern defined by a numerical modeling of wave refraction diagrams, representing circa 2000 km of the northeastern and eastern coasts of Brazil, permitted the regional-scale reproduction of several drift cells of net longshore sediment transport. Those drift cells can reasonably explain the coastal sections that present sediment surplus or sediment deficit, which correspond, respectively, to regions where there is deposition and erosion or little/no deposition of sand. The sediment deficit allows the exposure and maintenance of rocky substrates to be free of sediment, a favorable condition for the fixation and development of coral larvae.


Asunto(s)
Antozoos , Sedimentos Geológicos , Agua de Mar , Movimientos del Agua , Animales , Brasil , Densidad de Población , Dinámica Poblacional
16.
An. acad. bras. ciênc ; 80(1): 205-214, Mar. 2008. ilus, graf, mapas
Artículo en Inglés | LILACS | ID: lil-477427

RESUMEN

This paper shows that the location of the shoreface bank reefs along the northeastern and eastern coasts of Brazil, in a first order approximation, seem to be controlled by the deficit of sediment in the coastal system. The sediment transport pattern defined by a numerical modeling of wave refraction diagrams, representing circa 2000 km of the northeastern and eastern coasts of Brazil, permitted the regional-scale reproduction of several drift cells of net longshore sediment transport. Those drift cells can reasonably explain the coastal sections that present sediment surplus or sediment deficit, which correspond, respectively, to regions where there is deposition and erosion or little/no deposition of sand. The sediment deficit allows the exposure and maintenance of rocky substrates to be free of sediment, a favorable condition for the fixation and development of coral larvae.


Este trabalho mostra que a localização dos recifes de coral ao longo dos litorais leste e nordeste do Brasil, em uma aproximação de primeira ordem, parece ser controlada pelo déficit de sedimentos no sistema costeiro. O padrão de transporte de sedimentos definido por modelagem numérica a partir de diagramas de refração de ondas, representando cerca de 2000 km dos litorais leste e nordeste do Brasil, permitiu a reprodução, em escala regional, de várias células de deriva litorânea efetiva de sedimentos. Essas células de deriva podem razoavelmente explicar os segmentos costeiros que representam superávit, ou deficit de sedimentos que correspondem, respectivamente, a regiões onde existe deposição e erosão ou pouca/nenhuma deposição de areia. O deficit de sedimentos propicia a exposição e manutenção de substratos rochosos livres de sedimento, uma condição favorável para a fixação e desenvolvimento das larvas de coral.


Asunto(s)
Animales , Antozoos , Sedimentos Geológicos , Agua de Mar , Movimientos del Agua , Brasil , Densidad de Población , Dinámica Poblacional
17.
An Acad Bras Cienc ; 79(2): 333-41, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17625686

RESUMEN

This paper presents a numerical modeling estimation of the sediment dispersion patterns caused by waves inciding through four distinct coastline contours of the delta plain of the Doce River during the Late Holocene. For this, a wave climate model based on the construction of wave refraction diagrams, as a function of current boundary conditions, was defined and was assumed to be valid for the four coastlines. The numerical modeling was carried out on basis of the refraction diagrams, taking into account the angle of approximation and the wave height along the coastline. The results are shown to be comparable with existing data regarding the directions of net longshore drift of sediments estimated from the integration of sediment cores, interpretation of aerial photographs and C14 datings. This fact apparently suggests that, on average, current boundary conditions appear to have remained with the same general characteristics since 5600 cal yr BP to the present. The used approach may prove useful to evaluate the sediment dispersion patterns during the Late Holocene in the Brazilian east-northeast coastal region.

18.
Arch. Inst. Cardiol. Méx ; 56(6): 485-9, nov.-dic. 1986. ilus
Artículo en Español | LILACS | ID: lil-47228

RESUMEN

Se presenta el caso de un paciente, varón de 59 años, intervenido de prótesis de Björk en posición aórtica y comisurotomía mitral, con mala función ventricular y episodios repetidos de taquicardia ventricular (TV), a pesar del tratamiento anti-arrítmico con amiodarona. El estudio electrofisiológico (EEF) puso de manifiesto que la TV por reentrada cedía con extraestímulos (EE) aplicados en el apex del ventrículo derecho . Fuera de los episodios de TV, el paciente se mantenía con arritmia completa por fibrilación auricular, con frecuencias ventriculares medias lentas. Se implantó marcapaso Medtronic Spectrax 5985, multiprogramable, con posibilidad de programar a modo VVT y con períodos refractarios efectivos (PRE) programables cortos (220mseg). Durante las crisis de TV el MP se programaba temporalmente a modo VVT con PRE de 220 mseg y a través de estimulación torácica por medio del estimulador de electrofisiología se conseguían interrumpir las crisis de TV con EE (2 ó 3) sincronizados. Gracias al mecanismo de disparo ("triggered", la estimulación tóracica obliga al buscado disparo del marcapasos, que de este modo funcional igual que un estimulador externo de electrofisiología, siempre que se tengan en cuenta sus PRE y mantegan adecuados los umbrales de percepción y estimulación


Asunto(s)
Persona de Mediana Edad , Humanos , Masculino , Amiodarona/uso terapéutico , Taquicardia/tratamiento farmacológico , Estimulación Cardíaca Artificial , Marcapaso Artificial
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