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1.
Sci Total Environ ; 867: 161475, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36632900

RESUMO

The cellular and molecular mechanisms by which atmospheric pollution from particulate matter and/or electromagnetic fields (EMFs) may prove harmful to human health have not been extensively researched. We analyzed whether the combined action of EMFs and black carbon (BC) particles induced cell damage and a pro-apoptotic response in the HL-60 promyelocytic cell line when exposed to 2.45 GHz radio frequency (RF) radiation in a gigahertz transverse electromagnetic (GTEM) chamber at sub-thermal specific absorption rate (SAR) levels. RF and BC induced moderately significant levels of cell damage in the first 8 or 24 h for all exposure times/doses and much greater damage after 48 h irradiation and the higher dose of BC. We observed a clear antiproliferative effect that increased with RF exposure time and BC dose. Oxidative stress or ROS production increased with time (24 or 48 h of radiation), BC dose and the combination of both. Significant differences between the proportion of damaged and healthy cells were observed in all groups. Both radiation and BC participated separately and jointly in triggering necrosis and apoptosis in a programmed way. Oxidative-antioxidant action activated mitochondrial anti-apoptotic BCL2a gene expression after 24 h irradiation and exposure to BC. After irradiation of the cells for 48 h, expression of FASR cell death receptors was activated, precipitating the onset of pro-apoptotic phenomena and expression and intracellular activity of caspase-3 in the mitochondrial pathways, all of which can lead to cell death. Our results indicate that the interaction between BC and RF modifies the immune response in the human promyelocytic cell line and that these cells had two fates mediated by different pathways: necrosis and mitochondria-caspase dependent apoptosis. The findings may be important in regard to antimicrobial, inflammatory and autoimmune responses in humans.


Assuntos
Apoptose , Ondas de Rádio , Humanos , Células HL-60 , Necrose , Ondas de Rádio/efeitos adversos , Estresse Oxidativo , Carbono , Campos Eletromagnéticos
2.
Rev Clin Esp (Barc) ; 221(3): 131-138, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33998460

RESUMO

BACKGROUND: Although the incidence of papillary thyroid microcarcinoma (PTMC) has increased in recent decades, the role played by minimal extrathyroidal extension (mETE) in the prognosis of PTMC is still unclear. The aim of this study is to analyze the factors associated with PTMC with mETE and its long-term prognosis. MATERIAL AND METHODS: We conducted a retrospective study on patients with a histological diagnosis of PTMC. We excluded patients who had previously undergone thyroid surgery, those who had other synchronous malignancies, those with an ectopic location of the PTMC, and those lost to follow-up within two years. We compared group 1 (PTMC without extrathyroidal extension) to group 2 (PTMC with mETE) and performed a multivariate analysis. RESULTS: We observed PTMC with mETE in 11.2% (n = 18) of patients. On the multivariate analysis, mETE was associated with an age ≥45 years (OR: 4.383; 95% CI: 1.051-18.283, p = .043), tumor size ≥8 mm (OR: 5.913; 95% CI: 1.795-19.481; p = .003), bilaterality (OR: 4.430; 95% CI: 1.294-15.173; p = .018) and metastatic lymph nodes (OR: 12.588; 95% CI: 2.919-54.280; p = .001). Over the mean follow-up period of 119.8 ±â€¯65 months, one case of recurrence was detected in group 2 (0% vs. 5.6%; p = .112). No patients died of the disease. Disease-free survival was lower in group 2 (124.9 ±â€¯5.6 vs. 97.4 ±â€¯10.3 months; p = .034). CONCLUSIONS: The mETE of PTMC is a factor of worse prognosis associated with the presence of metastatic lymph nodes and a lower rate of disease-free survival.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Carcinoma Papilar/epidemiologia , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Glândula Tireoide/epidemiologia
3.
Rev. clín. esp. (Ed. impr.) ; 221(3): 131-138, mar. 2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-225899

RESUMO

Introducción Aunque el microcarcinoma papilar de tiroides (MCPT) ha sufrido un incremento en la incidencia en las últimas décadas, todavía no está claro qué papel desempeña la extensión extratiroidea mínima (EETm) en su pronóstico. El objetivo de este estudio es analizar los factores asociados al MCPT con EETm y su pronóstico a largo plazo. Material y métodos Estudio retrospectivo cuya población a estudio la constituyen los pacientes con diagnóstico histológico de MCPT. Se excluye a los pacientes con: cirugía tiroidea previa, otras enfermedades malignas sincrónicas, localización ectópica del MCPT o pérdida durante el seguimiento antes de los 2 años. Se comparan 2grupos: grupo 1 (MCPT sin extensión extratiroidea) y grupo 2 (MCPT con EETm). Se realiza un análisis multivariante. Resultados El 11,2% (n = 18) de los pacientes presentaron MCPT con EETm. En el análisis multivariante, la EETm se asoció con la edad ≥ 45 años (OR: 4,383; IC del 95%: 1,051-18,283; p = 0,043), el tamaño tumoral ≥ 8mm (OR: 5,913; IC del 95%; 1,795-19,481; p = 0,003), la bilateralidad (OR: 4,430, IC del 95%; 1,294-15,173; p = 0,018) y las adenopatías metastásicas (OR: 12,588; IC del 95%; 2,919-54,280; p = 0,001). Durante un seguimiento medio de 119,8 ± 65 meses, una recurrencia fue detectada en el grupo 2 (0% vs. 5,6%; p = 0,112). Ningún paciente falleció debido a la enfermedad. La supervivencia libre de enfermedad fue menor en el grupo 2 (124,9 ± 5,6 vs. 97,4 ± 10,3 meses; p = 0,034). Conclusión La EETm del MCPT es un factor de peor pronóstico, asociada a la presencia de adenopatías metastásicas y a una menor supervivencia libre de enfermedad (AU)


Background Although the incidence of papillary thyroid microcarcinoma (PTMC) has increased in recent decades, the role played by minimal extrathyroidal extension (mETE) in the prognosis of PTMC is still unclear. The aim of this study is to analyze the factors associated with PTMC with mETE and its long-term prognosis. Material and methods We conducted a retrospective study on patients with a histological diagnosis of PTMC. We excluded patients who had previously undergone thyroid surgery, those who had other synchronous malignancies, those with an ectopic location of the PTMC, and those lost to follow-up within 2years. We compared group 1 (PTMC without extrathyroidal extension) to group 2 (PTMC with mETE) and performed a multivariate analysis. Results We observed PTMC with mETE in 11.2% (n=18) of patients. On the multivariate analysis, mETE was associated with age ≥45 years (OR: 4.383; 95% CI: 1.051-18.283, p = .043), tumor size ≥8mm (OR: 5.913; 95% CL: 1.795-19.481; p = .003), bilaterality (OR: 4.430; 95% CI: 1.294-15.173; p = .018) and metastatic lymph nodes (OR: 12.588; 95% CI: 2.919-54.280; p = .001). During a mean follow-up of 119.8±65 months, one recurrence was detected in group 2 (0% vs. 5.6%; p = .112). No patients died of the disease. Disease-free survival was lower in group 2 (124.9±5.6 vs. 97.4±10.3 months; p = .034). Conclusions The mETE of PTMC is a factor of worse prognosis associated with the presence of metastatic lymph nodes and a lower rate of disease-free survival (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/epidemiologia , Carcinoma Papilar/epidemiologia , Estudos Retrospectivos , Metástase Linfática , Análise Multivariada , Fatores de Risco , Prognóstico
4.
Sci Total Environ ; 765: 142681, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33071139

RESUMO

Environmental factors such as air pollution by particles and/or electromagnetic fields (EMFs) are studied as harmful agents for human health. We analyzed whether the combined action of EMF with fine and coarse black carbon (BC) particles induced cell damage and inflammatory response in RAW 264.7 cell line macrophages exposed to 2.45 GHz in a gigahertz transverse electromagnetic (GTEM) chamber at sub-thermal specific absorption rate (SAR) levels. Radiofrequency (RF) dramatically increased BC-induced toxicity at high doses in the first 24 h and toxicity levels remained high 72 h later for all doses. The increase in macrophage phagocytosis induced after 24 h of RF and the high nitrite levels obtained by stimulation with lipopolysaccharide (LPS) endotoxin 24 and 72 h after radiation exposure suggests a prolongation of the innate and inflammatory immune response. The increase of proinflammatory cytokines tumor necrosis factor-α, after 24 h, and of interleukin-1ß and caspase-3, after 72 h, indicated activation of the pro-inflammatory response and the apoptosis pathways through the combined effect of radiation and BC. Our results indicate that the interaction of BC and RF modifies macrophage immune response, activates apoptosis, and accelerates cell toxicity, by which it can activate the induction of hypersensitivity reactions and autoimmune disorders.


Assuntos
Campos Eletromagnéticos , Ondas de Rádio , Animais , Carbono , Humanos , Macrófagos , Camundongos , Células RAW 264.7 , Ondas de Rádio/efeitos adversos
5.
Sensors (Basel) ; 20(11)2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32517140

RESUMO

In this work, the application of a technique for monitoring changes of the dielectric constant of the atmosphere caused by the presence of pollution is discussed. The method is based on changes in the reflection coefficient of the device induced by these dielectric constant variations of the surrounding medium. To that end, several Yagi-Uda-like antenna designs with different size limitations were simulated by using a Method-of-Moments software and optimized by means of a simulated annealing strategy. It has been found that the larger the optimal elements of the array are allowed to be, the higher the sensitivity reached. Thus, in a trade-off between sensitivity and moderate length (regarding flexibility purposes), the most promising solution has been built. This prototype has been experimentally tested in presence of an artificial aerosol made of PAO (polyalphaolefin) oil and black carbon inclusions of a size of 0.2 µm. As a result, potentials for developing a measurement procedure by means of changes in the characteristic parameters of the antenna led by different concentration levels of suspended particles in the surrounding medium are shown. In this manner, a local mapping of polluted levels could be developed in an easy, real-time, and flexible procedure.

6.
Rev Clin Esp ; 2020 Mar 23.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32216965

RESUMO

BACKGROUND: Although the incidence of papillary thyroid microcarcinoma (PTMC) has increased in recent decades, the role played by minimal extrathyroidal extension (mETE) in the prognosis of PTMC is still unclear. The aim of this study is to analyse the factors associated with PTMC and mETE and the long-term prognosis of PTMC. MATERIAL AND METHODS: We conducted a retrospective study with a population consisting of patients with a histological diagnosis of PTMC. We excluded patients who had previously undergone thyroid surgery, those who had other synchronous malignancies, those with an ectopic location of the PTMC and those lost to follow-up within 2years. We compared group 1 (PTMC without extrathyroidal extension) versus group 2 (PTMC with mETE) and performed a multivariate analysis. RESULTS: We observed PTMC with mETE in 11.2% (n=18) of the patients. In the multivariate analysis, mETE was associated with an age ≥45 years (OR, 4.383; 95% CI 1.051-18.283, p=.043), a tumour size ≥8mm (OR, 5.913; 95% CI 1.795-19.481; p=.003), bilaterality (OR, 4.430; 95% CI 1.294-15.173; p=.018) and metastatic lymph nodes (OR, 12.588; 95% CI 2.919-54.280; p=.001). During a mean follow-up of 119.8±65 months, one recurrence was detected in group 2 (0% vs. 5.6%; p=.112), but none of the patients died due to the disease. Disease-free survival was lower in group 2 (124.9±5.6 vs. 97.4±10.3 months; p=.034). CONCLUSIONS: The mETE of MCPT is a factor of worse prognosis, associated with the presence of metastatic lymph nodes and lower disease-free survival.

7.
J Photochem Photobiol B ; 178: 302-309, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29175604

RESUMO

In recent years, the management of food waste processing has emerged as a major concern. One such type of food waste, grape pomace, has been shown to be a great source of bioactive compounds which might be used for more environmentally - friendly processes for the synthesis of nanomaterials. In this study, grape pomace of Vitis vinifera has been used for the obtainment of an aqueous extract. Firstly, the reducing activity, total phenolic content and DPPH scavenging activity of the aqueous extract were determined. Then, the aqueous extract was used for the synthesis of gold and silver nanoparticles. The formation of spherical and stable nanoparticles with mean diameters of 35.3±5.2nm for Au@GP and 42.9±6.4nm for Ag@GP was confirmed by UV-vis spectroscopy and transmission electron microscopy. Furthermore, the functional group of biomolecules present in grape pomace extract, Au@GP and Ag@GP, were characterized by Fourier transform infrared spectroscopy prior to and after the synthesis, in order to obtain information about the biomolecules involved in the reducing and stabilization process. This study is the first to deal with the use of Vitis vinifera grape pomace in obtaining gold and silver nanoparticles through an eco-friendly, quick, one-pot synthetic route.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Prata/química , Vitis/química , Química Verde , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Extratos Vegetais/química , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier , Vitis/metabolismo
8.
Colloids Surf B Biointerfaces ; 153: 190-198, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28242372

RESUMO

This study is the first dealt with the use of brown macroalgae Cystoseira baccata (CB) extracts in obtaining gold nanoparticles (Au@CB) through an eco-friendly, fast, one-pot synthetic route. The formation of spherical, stable, polycrystalline nanoparticles with mean diameter of 8.4±2.2nm was demonstrated by UV-vis spectroscopy, TEM, HRTEM, STEM and zeta potential measurements. The extract appears to act as a protective agent where the particles are embedded, keeping them separated, avoiding aggregation and coalescence. The EELS and EDS analyses confirmed the elemental composition of the extract and nanoparticles. Moreover, the functional group of biomolecules present in CB and Au@CB were characterized by FTIR. The effects of CB extract and Au@CB were tested in vitro on the colon cancer cell lines HT-29 and Caco-2, as well as on normal primary neonatal dermal fibroblast cell line PCS-201-010. Results show a stronger cytotoxic effect against HT-29 than that on Caco-2; interestingly, a lack of toxicity on PCS-201-010 was obtained. Finally, the apoptotic activity was determined; Au@CB is able to induce apoptosis activation by the extrinsic and mitochondrial pathway in our CRC in vitro model. These encouraging results suggest that Au@CB has a significant potential for the treatment of colon rectal cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Ouro/farmacologia , Química Verde , Nanopartículas Metálicas/química , Phaeophyceae/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Células CACO-2 , Extratos Celulares/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ouro/química , Células HT29 , Humanos , Tamanho da Partícula , Relação Estrutura-Atividade , Propriedades de Superfície
9.
Gen Hosp Psychiatry ; 40: 39-46, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26971246

RESUMO

BACKGROUND: Cystic fibrosis (CF) is a chronic disease with an impact on the quality of life. Self-reported symptoms of depression and anxiety were assessed in the Spanish cohort of the International Epidemiological Study on Depression and Anxiety in patients with CF (International Depression-Anxiety Epidemiological Study) and their relationship with health status and health-related quality of life (HRQoL) was evaluated. METHODS: This cross-sectional study recruited adult patients with CF at 10 Spanish centers. Patients completed the Hospital Anxiety and Depression Scale (HADS) and the Revised Cystic Fibrosis Questionnaire. Demographic and health data were recorded from medical charts. Logistic regression was used to determine the predictors of elevated symptoms of depression and anxiety (HADS≥8). RESULTS: Of the 336 participants recruited (mean age, 28.1years; 48.2% women), 41 (12.2%) had elevated depression-related scores, and 100 (29.7%) had elevated anxiety-related scores (HADS≥8). After adjusting for confounders, only less education, intravenous antibiotics, psychiatric medications and psychotherapy were significantly associated with elevated psychological symptoms. Specifically, regardless of lung function, patients who were depressed or anxious reported worse HRQoL. CONCLUSIONS: The prevalence of elevated symptoms of depression and anxiety was high in Spanish adult patients with CF, and these symptoms were associated with a decreased HRQoL.


Assuntos
Ansiedade/diagnóstico , Fibrose Cística/psicologia , Depressão/diagnóstico , Qualidade de Vida , Adolescente , Adulto , Ansiedade/epidemiologia , Estudos Transversais , Fibrose Cística/epidemiologia , Depressão/epidemiologia , Feminino , Humanos , Masculino , Espanha/epidemiologia , Adulto Jovem
10.
Neurochem Res ; 36(12): 2322-32, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21818659

RESUMO

This study investigated the effects of microwave radiation on the PVN of the hypothalamus, extracted from rat brains. Expression of c-Fos was used to study the pattern of cellular activation in rats exposed once or repeatedly (ten times in 2 weeks) to 2.45 GHz radiation in a GTEM cell. The power intensities used were 3 and 12 W and the Finite Difference Time Domain calculation was used to determine the specific absorption rate (SAR). High SAR triggered an increase of the c-Fos marker 90 min or 24 h after radiation, and low SAR resulted in c-Fos counts higher than in control rats after 24 h. Repeated irradiation at 3 W increased cellular activation of PVN by more than 100% compared to animals subjected to acute irradiation and to repeated non-radiated repeated session control animals. The results suggest that PVN is sensitive to 2.45 GHz microwave radiation at non-thermal SAR levels.


Assuntos
Expressão Gênica/efeitos da radiação , Micro-Ondas , Núcleo Hipotalâmico Paraventricular/efeitos da radiação , Proteínas Proto-Oncogênicas c-fos/efeitos da radiação , Animais , Feminino , Proteínas Proto-Oncogênicas c-fos/biossíntese , Ratos , Ratos Sprague-Dawley
11.
J Endocrinol Invest ; 34(3): 170-4, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20479570

RESUMO

BACKGROUND: Thyroid gland is highly dependent on dietary intake of iodine for normal function, so it is particularly subjected to "endocrine disruptor" action. The human sodium/iodide symporter (hNIS) is an integral plasma membrane glycoprotein mediating the active transport of iodide into thyroid follicular cells, a crucial step for thyroid hormone biosynthesis. Beyond to perchlorate and thyocianate ions a few other inhibitors of iodide uptake have been described. AIM: The aim of this study was to investigate if 10 substances usually used as drugs in clinical practice were able to inhibit NIS-mediated iodide uptake in vitro. MATERIALS AND METHODS: A CHO cell line stably expressing hNIS was used to test any inhibition of NIS-mediated iodide uptake exerted by drugs. Perchlorate and thyocianate ions were used as positive controls. RESULTS: None of the analyzed substances was able to significantly inhibit iodide uptake in our system. As we expected, perchlorate and thyocianate ions were able to inhibit iodide uptake in a dose-dependent manner. CONCLUSIONS: In conclusion, we carried out an in vitro assay to evaluate the potential inhibitory effect of common drugs on NISmediated iodide uptake by using CHO-hNIS cells. None of the analyzed substances was able to inhibit iodide uptake; only perchlorate and thyocianate were able to inhibit iodide uptake in a dose-dependent manner.


Assuntos
Células CHO/metabolismo , Iodetos/metabolismo , Simportadores/metabolismo , Glândula Tireoide/metabolismo , Inibidores de 14-alfa Desmetilase/química , Inibidores de 14-alfa Desmetilase/farmacologia , Anfotericina B/química , Anfotericina B/farmacologia , Animais , Antialérgicos/química , Antialérgicos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Atropina/química , Atropina/farmacologia , Biotina/química , Biotina/farmacologia , Buspirona/química , Buspirona/farmacologia , Células CHO/efeitos dos fármacos , Cricetinae , Cricetulus , Econazol/química , Econazol/farmacologia , Humanos , Hidrocortisona/química , Hidrocortisona/farmacologia , Metronidazol/química , Metronidazol/farmacologia , Antagonistas Muscarínicos/química , Antagonistas Muscarínicos/farmacologia , Papaverina/química , Papaverina/farmacologia , Percloratos/farmacologia , Inibidores de Fosfodiesterase/química , Inibidores de Fosfodiesterase/farmacologia , Prometazina/química , Prometazina/farmacologia , Agonistas do Receptor de Serotonina/química , Agonistas do Receptor de Serotonina/farmacologia , Sulfadiazina/química , Sulfadiazina/farmacologia , Simportadores/genética , Tiocianatos/farmacologia , Glândula Tireoide/efeitos dos fármacos
12.
Proc West Pharmacol Soc ; 54: 24-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22423575

RESUMO

The renin-angiotensin system (RAS) is one of the most important systems in blood pressure homeostasis and pathogenesis of cardiovascular-renal diseases. When blood volume goes down, juxtaglomerular cells in the kidneys secrete renin. Renin stimulates the production of angiotensin I (Ang I), which is then converted to angiotensin II (Ang II). Angiotensin II causes blood vessels to constrict, resulting in increased blood pressure. If the renin angiotensin system is over active, blood pressure will be too high. Most hypotensive drugs are designed to block this system at different points in the pathway. In this study, we developed a mathematical model of the renin-angiotensin system to emulate the response of the renin-angiotensin system in humans. This model consists of a set of differential equations. Special attention is paid to the estimation of all the model parameters from reported experimental data. These equations allow us to model hypertensive and normotensive patients and pharmacotherapeutic approaches to treatment. We show dose-response curves of blood pressure and biochemical components of the renin-angiotensin system. Our results reproduce clinical outcomes. We conclude that mathematical modeling of RAS is a useful approach for gaining insight into the complexities of homeostatic control of arterial pressure and pharmacotherapeutics.


Assuntos
Hipertensão/tratamento farmacológico , Sistema Renina-Angiotensina/efeitos dos fármacos , Pressão Sanguínea , Humanos , Modelos Teóricos , Sistema Renina-Angiotensina/fisiologia
13.
J Colloid Interface Sci ; 316(2): 762-70, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17900606

RESUMO

Dynamic light scattering and Cryo-TEM measurements have allowed us to obtain the size and structure of spontaneous aggregates formed by mixtures of Aerosol OT, AOT, and ethylene glycol polymers of different molecular mass. The results presented in this work show that small unilamellar vesicles predominate in pure Aerosol OT solutions and in dilute polymer solutions mixed with AOT. In the latter case, elongated micelles coexist with unilamellar vesicles. When polymer concentration increases above a certain concentration, the small vesicles disappear and the size of the elongated micelles decreases to a radius compatible with spherical micelles. For PEG concentrations above the overlapping ones, spherical micelles coexist with very large aggregates probably formed by large rod like micelles or by superstructures of elongated micelles embedded in a polymer network. This behavior is consistent with theoretical models based in molecular mean-field theory [M. Rovira-Bru, D.H. Thompson, I. Szleifer, Biophys. J. 83 (2002) 2419]. The properties of the different types of aggregates are obtained by fluorescence spectroscopy and electrophoretic mobility measurements.


Assuntos
Ácido Dioctil Sulfossuccínico/química , Polietilenoglicóis/química , Ensaio de Desvio de Mobilidade Eletroforética/métodos , Microscopia Eletrônica/métodos , Microscopia de Fluorescência/métodos , Tamanho da Partícula , Propriedades de Superfície
14.
J Theor Biol ; 248(1): 37-47, 2007 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-17570404

RESUMO

In the last few years, the efforts to elucidate the mechanisms underlying the segmentation clock in various vertebrate species have multiplied. Early evidence suggested that oscillations are caused by one of the genes under the Notch signalling pathway (like those of the her or Hes families). Recently, Aulehla et al. [Wnt3a plays a major role in the segmentation clock controlling somitogenesis. Dev. Cell 4, 395-406] discovered that Axin2 (a gene under the Wnt3a signalling pathway) also oscillates in the presomitic mesoderm (PSM) of mice embryos and proposed some mechanisms through which the Notch and Wnt3a pathways may interact. They further suggested that a decreasing concentration of Wnt3a along the PSM may be the gradient the segmentation clock interacts with to form somites. These results were reviewed by Rida et al. [A notch feeling of somite segmentation and beyond. Dev. Biol. 265, 2-22], who introduced a complex clockwork comprising genes Hes1, Lfng (under the Notch pathway), and Axin2, as well as their multiple interactions. In the present work we develop a mathematical model based on the Rida et al. review and use it to tackle some of the questions raided by the Aulehla et al. paper: can the Axin2 feedback loop constitute a clock? Could a decreasing Wnt3a signaling constitute the wavefront, where phase is recorded and the spatial pattern laid down? What is the master oscillator?


Assuntos
Relógios Biológicos , Simulação por Computador , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Transdução de Sinais/fisiologia , Somitos/citologia , Animais , Proteína Axina , Proteínas do Citoesqueleto/genética , Camundongos , Modelos Biológicos , Receptor Notch1/genética
15.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 33(3): 110-112, mayo 2006. ilus
Artigo em Es | IBECS | ID: ibc-045538

RESUMO

El embarazo ectópico intersticial es un suceso raro, con gran morbimortalidad para la paciente si se diagnostica de forma tardía. Las opciones actuales de tratamiento son el empleo de metotrexato o bien el tratamiento quirúrgico. No se ha establecido aún cuál de ellas es la mejor opción. En publicaciones recientes se considera que el tratamiento médico es un método aceptable si se hace una selección adecuada de la paciente y un seguimiento estricto tras la aplicación de metotrexato (AU)


Interstitial pregnancy is a rare event, which produces high morbidity and mortality if diagnosis is delayed. Current treatment options consist of methotrexate or surgery. Which of these two options is the most effective remains to be established. Recent publications consider medical treatment as an acceptable method when there is appropriate patient selection and close follow-up after methotrexate therapy (AU)


Assuntos
Feminino , Gravidez , Humanos , Gravidez Ectópica , Gravidez Ectópica/cirurgia , Resultado do Tratamento
18.
Rev Clin Esp ; 205(1): 9-13, 2005 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-15718011

RESUMO

INTRODUCTION: In multinodular goiter there is no consensus on which is the most adequate surgical technique, since although the techniques with partial resection show lower risk of complications they are associated with a higher risk of recurrences. The objective of this study is to define the risk factors for recurrence of multinodular goiters after surgery in a series with a mean postoperative follow-up higher than 12 years. PATIENTS AND METHOD: 231 multinodular goiters with partial thyroid surgery are analyzed. The recurrence is assessed through clinical exploration, and is confirmed with echography. The variables analyzed are age, sex, family history of thyroid pathology, residence in goitrogenic areas, asymptomatic hyperthyroidism, compression syndromes, intrathoracic extension of goiter, surgeon experience with endocrine surgery, weight of the thyroid, and surgical technique, chi2 test, Student's t test and a logistic regression test are applied. RESULTS: After a mean postoperative follow-up of 152 +/- 71 months 67 goiters (29%) showed recurrence with a mean time for recurrence of 85 +/- 67 months. Risk factors detected in the multivariate study were youngest age, surgeon's lack of experience in endocrine surgery, and the surgical technique. Forty-six patients (69%) were operated because of recurrence, most of them by surgeons experienced in endocrine surgery. Thyroidectomy was completed in all cases, and two definitive postoperative complications occurred. CONCLUSIONS: The index of clinical recurrences is high and increases with the progression; primary risk factors are age, surgeon's experience, and surgical technique. The implication is that partial resection techniques should be carried out by surgeons with experience and there should be avoided in young patients.


Assuntos
Bócio Nodular/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva , Reoperação , Fatores de Risco , Tireoidectomia
19.
Rev. clín. esp. (Ed. impr.) ; 205(1): 9-13, ene. 2005. tab, graf
Artigo em Es | IBECS | ID: ibc-037261

RESUMO

Introducción. En el bocio multinodular no existe consenso sobre cuál es la técnica quirúrgica más adecuada, pues, aunque las técnicas resectivas parciales presentan menor riesgo de complicaciones, conllevan un alto riesgo de recidivas. El objetivo es determinar los factores de riesgo de recidiva del bocio multinodular tras la cirugía en una serie con un seguimiento medio postquirúrgico superior a los 12 años. Pacientes y método. Se analizan 231 bocios multinodulares con cirugía tiroidea parcial. La recidiva se valora mediante exploración clínica y se confirma mediante ecografía. Las variables analizadas son edad, sexo, antecedentes familiares de patología tiroidea, residir en áreas bociógenas, asintomático, hipertiroidismo, síndromes compresivos, prolongación intratorácica del bocio, experiencia en cirugía endocrina del cirujano, peso del tiroides y técnica quirúrgica. Se aplica la prueba de χ2, la de la «t» de Student y una prueba de regresión logística. Resultados. Con un seguimiento medio de 152 ± 71 meses recidivaron 67 bocios (29%) con un tiempo medio de recidiva de 85 ± 67 meses. Los factores de riesgo detectados en el estudio multivariante fueron la edad más joven, la no experiencia en cirugía endocrina del cirujano y la técnica quirúrgica. Cuarenta y seis pacientes (69%) fueron intervenidos de la recidiva, la mayoría por cirujanos con experiencia en cirugía endocrina. En todos los casos se completó la tiroidectomía y se presentaron dos complicaciones postoperatorias definitivas. Conclusiones. El índice de recidivas clínicas es alto y aumenta con la evolución, siendo los principales factores de riesgo la juventud, la experiencia del cirujano y la técnica quirúrgica. Por lo que que estas técnicas resectivas parciales deben realizarse por cirujanos con experiencia y evitarse en pacientes jóvenes


Introduction. In multinodular goiter there is no consensus on which is the most adequate surgical technique, since although the techniques with partial resection show lower risk of complications they are associated with a higher risk of recurrences. The objective of this study is to define the risk factors for recurrence of multinodular goiters after surgery in a series with a mean postoperative follow-up higher than 12 years. Patients and method. 231 multinodular goiters with partial thyroid surgery are analyzed. The recurrence is assessed through clinical exploration, and is confirmed with echography. The variables analyzed are age, sex, family history of thyroid pathology, residence in goitrogenic areas, asymptomatic hyperthyroidism, compression syndromes, intrathoracic extension of goiter, surgeon experience with endocrine surgery, weight of the thyroid, and surgical technique, χ2 test, Student’s «t» test and a logistic regression test are applied. Results. After a mean postoperative follow-up of 152±71 months 67 goiters (29%) showed recurrence with a mean time for recurrence of 85 ± 67 months. Risk factors detected in the multivariate study were youngest age, surgeon's lack of experience in endocrine surgery, and the surgical technique. Forty-six patients (69%) were operated because of recurrence, most of them by surgeons experienced in endocrine surgery. Thyroidectomy was completed in all cases, and two definitive postoperative complications occurred. Conclusions. The index of clinical recurrences is high and increases with the progression; primary risk factors are age, surgeon's experience, and surgical technique. The implication is that partial resection techniques should be carried out by surgeons with experience and there should be avoided in young patients


Assuntos
Adulto , Humanos , Bócio Nodular/cirurgia , Tireoidectomia , Seguimentos , Análise Multivariada , Recidiva , Reoperação , Fatores de Risco
20.
Gastroenterol Hepatol ; 26(6): 333-40, 2003.
Artigo em Espanhol | MEDLINE | ID: mdl-12809569

RESUMO

INTRODUCTION: Medical treatment for fulminat hepatic failure seeks spontaneous recovery of the liver function, but the results are very discouraging (50-80% mortality). Liver transplantation is an option in patients with a poor evolution despite medical treatment, with survival rates of > 50%. The ideal moment for performing the transplant is controversial, as it should not be done too soon, when the liver disease is still reversible, or tool late, when the patient is in an irreversible clinical situation. PATIENTS AND METHOD: A retrospective review was made of the clinical histories of 34 patients admitted to our hospital with a diagnosis of fulminant hepatic failure, of whom 26 underwent transplantation. The most frequent cause was viral, with 10 cases (38%); no aetiology at all could be established in 11 cases (42%). Thirteen patients had preoperative complications, the most frequent being renal insufficiency. As for degree of ABO/DR compatibility, 13 cases were identical (40%), 17 compatible (51%) and the other 3 incompatible (9%). RESULTS: Thirty-three transplants were performed in 26 patients: 4 were retransplants due to chronic rejection, 2 for primary graft failure and 1 for hyperacute rejection. The overall mortality rate was 46% (12 patients), the most frequent cause of death being infection (50%). The overall actuarial survival rate was 68% at 1 year, 63% at 3 years and 59% at 5 years. The factors of poor prognosis were renal and respiratory insufficiency, a grade D electroencephalogram, and encephalopathy grades III and IV, the latter being the only prognostic factor identified in the multivariate analysis. The prognostic factors for mortality were a grade D electroencephalogram, encephalopathy grades III and IV and respiratory insufficiency, the latter being the only prognostic factor identified in the multivariate analysis. CONCLUSIONS: The achievement of good results with the use of transplantation in the management of fulminant hepatic failure depends on an optimum selection of transplant candidates, which means identifying them early, i.e. early indication for transplant, reduction in mean waiting time and exclusion of factors of poor prognosis.


Assuntos
Falência Hepática/cirurgia , Transplante de Fígado , Adolescente , Idoso , Criança , Eletroencefalografia , Feminino , Rejeição de Enxerto , Encefalopatia Hepática/etiologia , Encefalopatia Hepática/mortalidade , Encefalopatia Hepática/cirurgia , Hepatite Viral Humana/complicações , Humanos , Falência Renal Crônica/complicações , Falência Hepática/complicações , Falência Hepática/tratamento farmacológico , Falência Hepática/mortalidade , Transplante de Fígado/mortalidade , Transplante de Fígado/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Espanha , Taxa de Sobrevida , Resultado do Tratamento
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