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1.
Arch Bronconeumol ; 2024 May 28.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38853119

RESUMO

BACKGROUND: Although the medium- and long-term sequelae of survivor of acute respiratory distress syndrome (ARDS) of any cause have been documented, little is known about the way in which COVID-19-induced ARDS affects functional disability and exercise components. Our aims were to examine the medium-term disability in severe COVID-19-associated ARDS survivors, delineate pathophysiological changes contributing to their exercise intolerance, and explore its utility in predicting long-term functional impairment persistence. METHODS: We studied 108 consecutive subjects with severe COVID-19 ARDS who remained alive 6 months after intensive care unit (ICU) discharge. Lung morphology was assessed with chest non-contrast CT scans and CT angiography. Functional evaluation included spirometry, plethysmography, muscle strength, and diffusion capacity, with assessment of gas exchange components through diffusing capacity of nitric oxide. Disability was assessed through an incremental exercise test, and measurements were repeated 12 and 24 months later in patients with functional impairments. RESULTS: At 6 months after ICU discharge, a notable dissociation between morphological and clinical-functional sequelae was identified. Moderate-severe disability was present in 47% of patients and these subjects had greater limitation of ventilatory mechanics and gas exchange, as well as greater symptomatic perception during exercise and a probable associated cardiac limitation. Female sex, hypothyroidism, reduced membrane diffusion component, lower functional residual capacity, and high-attenuation lung volume were independently associated with the presence of moderate-severe functional disability, which in turn was related to higher frequency and greater intensity of dyspnea and worse quality of life. Out of the 71 patients with reduced lung volumes or diffusion capacity at 6 months post-ICU discharge, only 19 maintained a restrictive disorder associated with gas exchange impairment at 24 months post-discharge. In these patients, 6-month values for diffusion membrane component, maximal oxygen uptake, ventilatory equivalent for CO2, and dead space to tidal volume ratio were identified as independent risk factors for persistence of long-term functional sequelae. CONCLUSIONS: Less than half of survivors of COVID-19 ARDS have moderate-severe disability in the medium term, identifying several risk factors. In turn, diffusion membrane component and exercise tolerance at 6-month ICU discharge are independently associated with the persistence of long-term functional sequelae.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35954927

RESUMO

The present study investigates the effects of peripheral spatial cues and optically distorting augmentations over eccentric vision mechanisms in normally sighted participants with simulated scotoma. Five different augmentations were tested inside a virtual reality (VR)-gaming environment. Three were monocular spatial cues, and two were binocular optical distortions. Each was divided into three conditions: baseline with normal viewing, augmentation with one of the assistance methods positioned around the scotoma, and one with only the simulated central scotoma. The study found that the gaming scenario induced eccentric viewing for the cued augmentation groups, even when the peripheral assistance was removed, while for the optical distortions group, the eccentric behavior disappeared after the augmentation removal. Additionally, an upwards directionality of gaze relative to target during regular gaming was found. The bias was maintained and implemented during and after the cued augmentations but not after the distorted ones. The results suggest that monocular peripheral cues could be better candidates for implementing eccentric viewing training in patients. At the same time, it showed that optical distortions might disrupt such behavior. Such results are noteworthy since distortions such as zoom are known to help patients with macular degeneration see targets of interest.


Assuntos
Degeneração Macular , Jogos de Vídeo , Realidade Virtual , Sinais (Psicologia) , Humanos , Escotoma
3.
Vision Res ; 179: 75-84, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33310640

RESUMO

Progressive addition lenses introduce distortions in the peripheral visual field that alter both form and motion perception. Here we seek to understand how our peripheral visual field adapts to complex distortions. The adaptation was induced across the visual field by geometrically skewed image sequences, and aftereffects were measured via changes in perception of the double-drift illusion. The double-drift or curveball stimulus contains both local and object motion. Therefore, the aftereffects induced by geometrical distortions might be indicative of how this adaptation interacts with the local and object motion signals. In the absence of the local motion components, the adaptation to skewness modified the perceived trajectory of object motion in the opposite direction of the adaptation stimulus skew. This effect demonstrates that the environment can also tune perceived object trajectories. Testing with the full double-drift stimulus, adaptation to a skew in the opposite direction to the local motion component induced a change in perception, reducing the illusion magnitude (when the stimulus was presented on the right side of the screen. A non-statistically significant shift, when stimuli were on the left side). However, adaptation to the other orientation resulted in no change in the strength of the double-drift illusion (for both stimuli locations). Thus, it seems that the adaptor's orientation and the motion statistics of the stimulus jointly define the perception of the measured aftereffect. In conclusion, not only size, contrast or drifting speed affects the double-drift illusion, but also adaptation to image distortions.


Assuntos
Ilusões , Percepção de Movimento , Adaptação Fisiológica , Humanos , Movimento (Física)
4.
J Clin Med ; 9(6)2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32599775

RESUMO

Clinical studies and basic research have attempted to establish a relationship between myopia progression and single vision spectacle wear, albeit with unclear results. Single vision spectacle lenses are continuously used as the control group in myopia control trials. Hence, it is a matter of high relevance to investigate further whether they yield any shift on the refractive state, which could have been masked by being used as a control. In this review, eye development in relation to eyes fully corrected versus those under-corrected is discussed, and new guidelines are provided for the analysis of structural eye changes due to optical treatments. These guidelines are tested and optimised, while ethical implications are revisited. This newly described methodology can be translated to larger clinical trials, finally exerting the real effect of full correction via single vision spectacle lens wear on eye growth and myopia progression.

5.
Sci Rep ; 9(1): 18487, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811185

RESUMO

To evaluate the impact of multifocal contact lens wear on the image quality metrics across the visual field in the context of eye growth and myopia control. Two-dimensional cross-correlation coefficients were estimated by comparing a reference image against the computed retinal images for every location. Retinal images were simulated based on the measured optical aberrations of the naked eye and a set of multifocal contact lenses (centre-near and centre-distance designs), and images were spatially filtered to match the resolution limit at each eccentricity. Value maps showing the reduction in the quality of the image through each optical condition were obtained by subtracting the optical image quality from the theoretical physiological limits. Results indicate that multifocal contact lenses degrade the image quality independently from their optical design, though this result depends on the type of analysis conducted. Analysis of the image quality across the visual field should not be oversimplified to a single number but split into regional and groups because it provides more insightful information and can avoid misinterpretation of the results. The decay of the image quality caused by the multifocal contacts alone, cannot explain the translation of peripheral defocus towards protection on myopia progression, and a different explanation needs to be found.

6.
PLoS One ; 14(4): e0213574, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30939130

RESUMO

The popularity of myopia treatments based on the peripheral defocus theory has risen. So far, little evidence has emerged around the questions which of these treatments are effective and why. In order to establish a framework that enables clinicians and researchers to acknowledge the possible interactions of different defocus patterns across the retina, different peripheral refractive errors (PRX) of subjects and different designs of optical treatments were evaluated. Dioptric defocus patterns on the retinal level have been obtained by merging the matrices of dioptric defocus maps of the visual field of different scenarios with individual peripheral refractive errors and different optical designs of multifocal contact lenses. The newly obtained matrices were statistically compared using a non-parametric test with familywise error algorithms and multi-comparison tests. Results show that asymmetric peripheral refractive error profiles (temporal or nasal positively skewed) appear to be less prone to be changed by the defocus imposition of multifocal contact lenses than those presenting symmetric patterns (relative peripheral myopia or hyperopia).


Assuntos
Olho/patologia , Hiperopia/terapia , Miopia/terapia , Retina/patologia , Adulto , Feminino , Fóvea Central/fisiopatologia , Humanos , Hiperopia/patologia , Cristalino/patologia , Masculino , Miopia/patologia
7.
PLoS One ; 13(11): e0207637, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30444900

RESUMO

Studies have found reduced myopia progression with multifocal contact lenses, albeit with an unclear mechanism behind their protective effect. It is hypothesized that the induced myopic defocus of the addition zones of the multifocal contact lenses leads to choroidal thickening and therefore inhibits eye growth. In the current study, the effect of the optical design of multifocal contact lenses on choroidal thickness was investigated. Eighteen myopic participants wore four different contact lenses ((1) single-vision lenses corrected for distance, (2) single-vision lenses with +2.50 D full-field defocus, (3) Multifocal center-distance design, (4) Multifocal center-near design, both with addition power +2.50 D) for 30 min each on their right eye. Automated analysis of the macular choroidal thickness and vitreous chamber depth were performed before and after the wear of each of the contact lenses. Peripheral refraction profiles in primary gaze were obtained using eccentric photorefraction prior to contact lens wear. Choroidal thickness and vitreous chamber depth showed no significant differences to baseline with any of the contact lenses (all p > 0.05). Choroidal thickness increased by +2.1 ± 11.1 µm with the Multifocal center-distance design, by +2.0 ± 11.1 µm with the full-field defocus lens, followed by the Multifocal center-near design with +1.6 ± 11.3 µm and the single-vision contact lens correcting for distance with +0.9 ± 11.2 µm. Multifocal contact lenses have no significant influence on choroidal thickness after short-term wear. Therefore, changes in choroidal thickness might not be the main contributor to the protective effect of multifocal contact lenses in myopia control.


Assuntos
Lentes Intraoculares Multifocais , Miopia/patologia , Miopia/terapia , Acomodação Ocular , Adulto , Corioide/patologia , Desenho de Equipamento , Feminino , Humanos , Masculino , Miopia/fisiopatologia , Estudos Prospectivos , Refração Ocular , Testes Visuais , Adulto Jovem
8.
Pancreatology ; 18(2): 161-167, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29395619

RESUMO

BACKGROUND/OBJECTIVES: Development and validation of a multivariate prediction model for patients with acute pancreatitis (AP) admitted in Intensive Care Units (ICU). METHODS: A prospective multicenter observational study, in 1 year period, in 46 international ICUs (EPAMI study). PATIENTS: adults admitted to an ICU with AP and at least one organ failure. INTERVENTIONS: Development of a multivariate prediction model, using the worst data of the stay in ICU, based in multivariate analysis, simple imputation in a development cohort. The model was validated in another cohort. RESULTS: 374 patients were included (mortality of 28.9%). Variables with statistical significance in multivariate analysis were age, no alcoholic and no biliary etiology, development of shock, development of respiratory failure, need of continuous renal replacement therapy, and intra-abdominal pressure. The model created with these variables presented an AUC of ROC curve of 0.90 (CI 95% 0.81-0.94) in the validation cohort. We developed a multivariable prediction model, and AP cases could be classified as low mortality risk (between 2 and 9.5 points, mortality of 1.35%), moderate mortality risk (between 10 and 12.5 points, 28.92% of mortality), and high mortality risk (13 points of more, mortality of 88.37%). Our model presented better AUC of ROC curve than APACHE II (0.91 vs 0.80) and SOFA in the first 24 h (0.91 vs 0.79). CONCLUSIONS: We developed and validated a multivariate prediction model, which can be applied in any moment of the stay in ICU, with better discriminatory power than APACHE II and SOFA in the first 24 h.


Assuntos
Unidades de Terapia Intensiva , Pancreatite/patologia , Doença Aguda , Idoso , Estado Terminal , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Escores de Disfunção Orgânica , Pancreatite/diagnóstico , Pancreatite/terapia , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , América do Sul , Síndrome de Resposta Inflamatória Sistêmica
10.
Arch Esp Urol ; 68(4): 443-7, 2015 May.
Artigo em Espanhol | MEDLINE | ID: mdl-26033766

RESUMO

OBJECTIVES: Urologists daily evaluate many women with voiding disturbances, but proper physical examination has only rarely been previously performed. CASE DESCRIPTION: Case 1: 16-year-old woman presenting augmented daytime urinary frequency and nocturia without enuresis, with drop-by-drop micturition. Case 2: 80-year-old woman with urgency. She referred normal voiding with insensitive urinary loss the hour after. PHYSICAL EXAMINATION: adhesion of the labia minora. TREATMENT: Surgical section of the adhered area in the midline was performed with satisfactory aesthetic and clinical results. CONCLUSIONS: The adhesion of the labia minora is an acquired disease, more frequent in girls under 2 years. Several predisposing factors have been proposed: oestrogen deprivation, inadequate personal care, local irritants, infections or previous trauma. Differential diagnosis is required among three congenital pathologies: vaginal agenesis, imperforated hymen and ambiguous genitalia. Cases in postpubertal or postmenopausal women, or refractory to medical treatment are considered for surgery.


Assuntos
Exame Físico , Transtornos Urinários/etiologia , Vulva/anormalidades , Adolescente , Idoso de 80 Anos ou mais , Anormalidades Congênitas/diagnóstico , Feminino , Humanos , Síndrome
11.
Insuf. card ; 10(1): 11-18, mar. 2015. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-750482

RESUMO

Introducción. La terapia de resincronización cardíaca es un tratamiento eficaz para el tratamiento de la insuficiencia cardíaca, que reduce la mortalidad y el número de hospitalizaciones, y mejora la calidad de vida. Material y métodos. Se evalúa la eficiencia de la resincronización cardíaca comparada con el mejor tratamiento farmacológico mediante una evaluación económica adaptada a nuestro entorno sanitario. Se realizan varios modelos económicos de Markov. Se usa la perspectiva del sistema sanitario; el horizonte temporal es la duración prevista del dispositivo, estimada en 7 años. Se incluyen parámetros derivados de ensayos clínicos y estudios observacionales, tanto de pacientes ambulatorios como hospitalizados, y de un meta-análisis. Los participantes son pacientes con insuficiencia cardíaca sintomática en estadios funcionales III-IV según New York Heart Association, con QRS ancho, depresión grave de la función sistólica y ritmo sinusal. Se compara la resincronización cardíaca añadida al mejor tratamiento médico, frente a ese tratamiento médico óptimo. Las variables de resultado fueron años de vida y años de vida ajustados por calidad. Resultados. La resincronización cardíaca, añadida al mejor tratamiento médico, es un tratamiento coste-efectivo, con valores de ratio coste-efectividad de € 6.627 - 8.739 por año de vida ajustado a calidad de vida. Conclusiones. La resincronización cardíaca es un tratamiento eficiente, o coste-efectiva, para estos pacientes seleccionados. Este resultado varía poco al modificar las variables incluidas en el modelo. La inclusión de dispositivos con funcionalidad desfibrilador automático implantable no se ha incluido en nuestro trabajo, pero su valor probablemente sea mucho mayor.


Introduction. The therapy of cardiac resynchronization is effective for the treatment of the heart failure, which reduces mortality and number of hospitalizations, and improves quality of life. Material and methods. We evaluate the efficiency of the cardiac resynchronization compared with the best pharmacological therapy by means of an economic evaluation adapted to our sanitary environment. We developed several economic models of Markov. The perspective of the sanitary system is used; the temporary horizon is the duration foreseen of the device, estimated in 7 years. There are included parameters derived from clinical trials and observational studies, with ambulatory and hospitalized patients, and from a meta-analysis. They are patients with symptomatic heart failure with functional class NYHA III-IV, with wide QRS, severe depression of systolic function and sinusal rhythm. We compare cardiac resynchronization added to the best medical treatment, opposite to this medical treatment. Measured variables are years of life and years of life adjusted by quality. Results. The cardiac resynchronization added to the best medical treatment, is a cost- effective treatment, with values of incremental cost - effectiveness of € 6,627 - 8,739 for year of life adjusted to quality of life. Conclusions. The cardiac resynchronization is a cost-effective treatment for these patients. This result changes little on having modified the variables included in the model. The incorporation of devices with implantable cardioverter defibrillator functionality has not been included in our work, but his value probably is greater.


Introdução. A terapia de ressincronização cardíaca é um tratamento eficaz para a insuficiência cardíaca, que reduz a mortalidade e hospitalizações, e melhora a qualidade de vida. Material e métodos. É avaliada a eficiência da terapia de ressincronização cardíaca em comparação com o melhor tratamento de drogas através de uma avaliação econômica adaptada ao nosso ambiente de saúde. Vários modelos econômicos de Markov são realizados. A perspectiva do sistema de saúde é usada; o horizonte de tempo é o tempo de vida do dispositivo, estimada em 7 anos. Parâmetros derivados de ensaios clínicos e estudos observacionais, tanto ambulatoriais e internações, e uma meta-análise está incluída. Os participantes são pacientes com insuficiência cardíaca sintomática com NYHA III- IV, com QRS largo, depressão grave da função sistólica e do ritmo sinusal estágios funcionais. Ressincronização cardíaca adicionada a melhor terapia médica é comparado com o tratamento clínico otimizado. As variáveis respostas foram anos de vida e anos de vida ajustados pela qualidade. Resultados. Terapia de ressincronização cardíaca, somada à melhor terapia médica, é um tratamento de baixo custo com valores de relação custo- eficácia dos € 6627-8739 por ano de vida ajustado por qualidade de vida. Conclusões. Terapia de ressincronização cardíaca é um tratamento de baixo custo para esses pacientes selecionados. Esse resultado varia pouco alterando as variáveis incluídas no modelo. A inclusão de dispositivos com funcionalidades cardioversor desfibrilador implantável não foi incluído em nosso trabalho, mas o seu valor é, provavelmente, muito maior.


Assuntos
Humanos , Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca
12.
Clin Biochem ; 43(9): 720-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20303344

RESUMO

OBJECTIVES: To assess the accuracy of plasma levels of soluble Triggering Receptor Expressed on Myeloid cells (sTREM)-1 to diagnose infection in critical patients with systemic inflammatory response syndrome (SIRS). DESIGN AND METHODS: We prospectively studied 114 patients with SIRS criteria. The patients' plasma levels of sTREM-1 were measured within 24h of admission to the intensive care unit. The final diagnosis of infection was made independently by two investigators, who were blinded to the levels of sTREM-1. RESULTS: The area under the ROC curve of sTREM-1 for the diagnosis of sepsis was 0.62 (95% confidence interval [95% CI] 0.51-0.72). The diagnostic odds ratio of sTREM-1 after adjusting for the Infection Probability Score and procalcitonin plasma levels was 1.81 (95% CI 0.66-4.98; p=0.2508). CONCLUSIONS: In critical patients admitted with SIRS, sTREM-1 has poor discriminative power to identify patients with infection, and sTREM-1 levels do not add diagnostic information to that provided by other routinely available clinical tests.


Assuntos
Glicoproteínas de Membrana/sangue , Receptores Imunológicos/sangue , Sepse/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Adulto , Idoso , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Curva ROC , Receptor Gatilho 1 Expresso em Células Mieloides
13.
Arch Esp Urol ; 62(2): 131-3, 2009 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-19448280

RESUMO

BACKGROUND: We report a rare case of horses-hoe kidney trauma. METHODS: 67 years old man with a horseshoe kidney, which presented a fracture of the isthmus after falling. RESULTS: The diagnosis was made by IV contrast CT scan. He underwent exploratory laparotomy due to hemodynamic instability and radiologic findings on the CT scan. CONCLUSIONS: The rupture of a horseshoe kidney is a rare injury. CT scan is the test of choice to classify the degree of injury. Depending on the patient's hemodynamic stability and the findings on the CT scan the options are conservative orimmediate surgical treatment.


Assuntos
Rim/anormalidades , Rim/lesões , Idoso , Humanos , Masculino , Ruptura
14.
Aten Primaria ; 40(4): 177-86, 2008 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-18405582

RESUMO

OBJECTIVES: To determine whether treatment with phyto-oestrogens or soya protein succeeds in lowering blood pressure. DESIGN: A systematic review, evaluating all the observation studies and clinical trials, was conducted, followed by a meta-analysis to evaluate blood pressure variations in patients treated with phyto-oestrogens. SEARCH: The search strategy adopted used the terms "phyto-oestrogens," "soya meals," "hypertension," and "blood pressure." DATA SOURCES: The data bases MEDLINE, EMBASE, Cochrane, OVID were used, without time or language restrictions. References in the relevant articles were searched for manually. STUDY SELECTION: Two independent reviewers analysed the studies found in the search. DATA EXTRACTION: The Jadad scale was used for the clinical trials and the numerical data in the text or referred to in tables were extracted. Evaluation was made of which observational and experimental articles showed a drop in blood pressure with phyto-oestrogens and which did not. In the meta-analysis, data on sample size, difference in blood pressure before and after intervention and standard deviation were extracted from each study. The weighted difference of means was used with the model of randomised effects. The Review Manager v4.2.9 programme was used. RESULTS: No significant variations in blood pressure were found, whether systolic (-1.20 mm Hg; 95% CI, -2.80 to 0.41 mm Hg) or diastolic (-1.31 mm Hg; 95% CI, -2.73 to 0.11). If there were any variations, they are clinically of little importance. There was also an important degree of both statistical and clinical heterogeneity. CONCLUSIONS: There are no statistically significant or clinically important differences in blood pressure between patients treated with phyto-oestrogens and those not treated.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Fitoestrógenos/uso terapêutico , Alimentos de Soja , Diástole/efeitos dos fármacos , Humanos , Sístole/efeitos dos fármacos
15.
Biotechnol Prog ; 24(1): 187-91, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18092800

RESUMO

d-Amino acid oxidase (DAAO) was used to study the oxidative deamination of racemic mixtures of d,l-methionine in its soluble and immobilized forms and thus obtain the corresponding alpha-keto acid. The soluble enzyme form was obtained from a Trigonopsis variabilis CBS 4095 extract, free of l-amino acid oxidase, and was co-immobilized with a 200-fold excess of catalase to avoid the undesirable side reaction of H2O2 with the alpha-keto acid, which would otherwise render its corresponding decarboxylated acid, the 3-methylthiopropionic acid (MTPA). With this biocatalyst, quantitative conversion (>98%) of d-methionine into the alpha-keto acid 4-methylthio-2-oxobutyric acid (MTOB) and into MTPA was achieved using 5 mg.mL(-1) of biocatalyst at pH 8.0, 25 degrees C, and pure oxygen at 3 vvm. A stirred tank reactor with in situ product removal (STR-ISPR) was developed to avoid conversion of MTOB into MTPA. The reaction medium was re-circulated through a strong anion exchange column (Amberlite IRA-400). This resulted in the complete removal of MTOB from the reaction medium. After the reaction, the reaction products were eluted sequentially with water (l-methionine), 10 mM HCl (MTPA), and 0.5 M HCl (MTOB). After elution, MTOB was crystallized to its sodium salt.


Assuntos
Reatores Biológicos , D-Aminoácido Oxidase/metabolismo , Metionina/análogos & derivados , Ascomicetos/enzimologia , Espectroscopia de Ressonância Magnética , Metionina/química , Metionina/metabolismo , Estrutura Molecular
16.
Biochim Biophys Acta ; 1783(5): 803-12, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18062928

RESUMO

Characterization of intracellular pathways underlying the pleiotropic actions of insulin-like growth factor-I (IGF-I) on brain cells is incomplete. We analyzed IGF-I signalling on astrocytes through the canonical phosphatidylinositol 3-kinase (PI3K)/Akt pathway and focused on possible changes in PTEN, a phosphatase that modulates IGF-I signalling by inhibiting Akt activation and, in turn is positively regulated by PI3K. After exposure of astrocytes to IGF-I, PTEN mRNA and protein levels were reduced and its phosphatase activity diminished. Inhibition of PTEN involved activation of a PI3K/protein kinase C (PKC) pathway that decreased in a proteasome-dependent step the levels of the transcription factor Egr-1, a key regulator of PTEN levels in astrocytes, causing decreased binding of Egr-1 to the PTEN promoter. Enhanced mitogenesis in PTEN siRNA-transduced astrocytes after IGF-I suggested that reduced PTEN may be a permissive factor for the mitogenic activity of IGF-I. Subsequent recovery of reduced PTEN required also activation by IGF-I of PI3K to recruit in this case protein kinase A (PKA) which stimulated Egr-1 levels and, consequently PTEN synthesis. Because basal levels of PTEN in astrocytes are also governed by PI3K, IGF-I appears to modulate PTEN in astrocytes by redirecting its homeostasic control through PI3K in a timed fashion.


Assuntos
Astrócitos/enzimologia , Fator de Crescimento Insulin-Like I/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Humanos , PTEN Fosfo-Hidrolase/genética , Proteína Quinase C/metabolismo , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais
17.
J Neurosci ; 27(33): 8745-56, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17699657

RESUMO

Maladaptive inflammation is a major suspect in progressive neurodegeneration, but the underlying mechanisms are difficult to envisage in part because reactive glial cells at lesion sites secrete both proinflammatory and anti-inflammatory mediators. We now report that astrocytes modulate neuronal resilience to inflammatory insults through the phosphatase calcineurin. In quiescent astrocytes, inflammatory mediators such as tumor necrosis factor-alpha (TNF-alpha) recruits calcineurin to stimulate a canonical inflammatory pathway involving the transcription factors nuclear factor kappaB (NFkappaB) and nuclear factor of activated T-cells (NFAT). However, in reactive astrocytes, local anti-inflammatory mediators such as insulin-like growth factor I also recruit calcineurin but, in this case, to inhibit NFkappaB/NFAT. Proof of concept experiments in vitro showed that expression of constitutively active calcineurin in astrocytes abrogated the inflammatory response after TNF-alpha or endotoxins and markedly enhanced neuronal survival. Furthermore, regulated expression of constitutively active calcineurin in astrocytes markedly reduced inflammatory injury in transgenic mice, in a calcineurin-dependent manner. These results suggest that calcineurin forms part of a molecular pathway whereby reactive astrocytes determine the outcome of the neuroinflammatory process by directing it toward either its resolution or its progression.


Assuntos
Astrócitos/metabolismo , Calcineurina/metabolismo , Inflamação/patologia , Transdução de Sinais/fisiologia , Animais , Animais Recém-Nascidos , Astrócitos/efeitos dos fármacos , Lesões Encefálicas/complicações , Células Cultivadas , Interações Medicamentosas , Regulação da Expressão Gênica/fisiologia , Proteína Glial Fibrilar Ácida/genética , Humanos , Inflamação/etiologia , Inflamação/prevenção & controle , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Quinase Induzida por NF-kappaB
18.
An. otorrinolaringol. mex ; 45(4): 173-176, sept.-nov. 2000. tab, CD-ROM
Artigo em Espanhol | LILACS | ID: lil-304472

RESUMO

Propósito. El objetivo de este estudio fue presentar casos representativos de patología quirúrgica tiroidea poco frecuente haciendo énfasis en los criterios diagnósticos y terapéuticos considerados en cada caso. Selección de pacientes. Todos los expedientes clínicos con patología quirúrgica tiroidea poco frecuente en un período de 10 años (1990-1999). Parámetros de medición. La forma de asignación de los casos fue considerar como poco frecuente la patología quirúrgica que representa menos del 10 por ciento de los casos. Hallazgos. Se identificaron 8 casos de patología quirúrgica tiroidea poco frecuente: 2 casos de tiroides ectópica, 1 caso de carcinoma papilar en quiste tirogloso, 2 casos de metástasis cervical de carcinoma tiroideo oculto. 1 caso de tiroiditis supurativa y 2 casos de tumores que simulan quiste tirogloso. Conclusión. Existe una variedad amplia de patología quirúrgica tiroidea la cual puede tener presentación poco frecuente. Se requiere un protocolo de estudio adecuado para cada patología para evitar tratamiento erróneo o incompleto.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Patologia Cirúrgica , Cisto Tireoglosso , Doenças da Glândula Tireoide , Nódulo da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide
19.
An. otorrinolaringol. mex ; 44(4): 191-4, sept.-nov. 1999. ilus
Artigo em Espanhol | LILACS | ID: lil-276935

RESUMO

La enfermedad de Castleman es una enfermedad poco frecuente, caracterizada por proliferación masiva de tejido linfoide. Aparece en 70 por ciento de los casos como un tumor solitario en el mediastino. La presentación primaria en el cuello ocurre en 6 por ciento de los casos. Se reporta un caso de enfermedad de Castleman que se manifestó como un tumor cervical solitario asintomático


Assuntos
Humanos , Masculino , Adulto , Neoplasias de Cabeça e Pescoço/diagnóstico , Hiperplasia do Linfonodo Gigante/diagnóstico , Hiperplasia do Linfonodo Gigante/terapia , Hiperplasia do Linfonodo Gigante , Hiperplasia/etiologia
20.
An. otorrinolaringol. mex ; 44(3): 167-72, jun.-ago. 1999. ilus
Artigo em Espanhol | LILACS | ID: lil-276932

RESUMO

Introducción. Las micosis de senos paranasales se han clasificado en invasiva y no invasiva; el tipo de micosis y su comportamiento clínico depende de la interacción entre la competencia inmunológica del paciente y la patogenicidad del microorganismo, en un determinado micro ambiente. Material y Métodos. Se realizó un estudio clínico prospectivo para evaluar las características de pacientes con sinusitis micótica. Se presentan todos los pacientes diagnosticados y tratados como sinusitis micótica en el periodo de 1994-1997. Resultados. Se encontraron 10 pacientes que correspondieron al 6 por ciento de los casos de sinusitis crónica tratados quirúrgicamente; Todos los pacientes con mucormicosis aguda invasiva recibieron tratamiento medico con anfotericina B, Insulina y refección quirúrgica con debridación extensa del tejido necrótico, resultando en control de la enfermedad subyacente y sobrevida del 50 por ciento de los pacientes. Conclusión. Es necesario diagnosticar precozmente, y dar tratamiento multi disciplinario médico y quirúrgico para lograr una mejor supervivencia de los pacientes


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Aspergilose/diagnóstico , Mucormicose/epidemiologia , Mucormicose/patologia , Micoses/epidemiologia , Micoses/patologia , Sinusite/etiologia , Seios Paranasais/microbiologia , Seios Paranasais/patologia
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