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1.
Retina ; 41(3): 555-562, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32604342

RESUMEN

PURPOSE: To correlate drusen morphology and outer retinal status with autofluorescence (AF) imaging in patients with intermediate age-related macular degeneration. METHODS: Drusen type and morphology were analyzed using color fundus photography and spectral-domain optic coherence tomography, whereas fundus AF was used for drusen AF evaluation. Additional structural changes on spectral-domain optic coherence tomography, such as disruption of external limiting membrane, ellipsoid zone, and retinal pigment epithelium/Bruch membrane complex, as well as the presence of choroidal hypertransmission at correspondent locations were also evaluated and correlated with fundus AF findings. Spearman's correlation coefficient was used to analyze the correlation between spectral-domain optic coherence tomography morphological characteristics of drusen and AF appearance of the corresponding drusen. Strength of correlation was calculated (r), and a P value < 0.05 was considered statistically significant. RESULTS: Two hundred and twenty-eight drusen from 53 eyes of 53 patients were analyzed, 130 soft drusen (57.02%) and 98 cuticular drusen (42.98%). Sixty percent of the drusen were isoautofluorescent (n = 136), 35% hyperautofluorescent (n = 80), and 5% hypoautofluorescent (n = 12). We found positive correlation between drusen AF and hyperreflective foci (r = 0.4). Outer retinal layers morphology (external limiting membrane and ellipsoid zone status and hypertransmission) also correlates with autofluorescent findings (r = 0.3). CONCLUSION: Multimodal imaging reveals a broad spectrum of ultrastructural changes, which may reflect different stages in the evolution of drusen. Our results suggest that drusen morphological characteristics and autofluorescent findings are correlated but other factors or cofactors may be involved. The described correlations will help us understand new progression biomarkers of nonexudative age-related macular degeneration.


Asunto(s)
Angiografía con Fluoresceína/métodos , Oftalmoscopía/métodos , Imagen Óptica , Drusas Retinianas/diagnóstico , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Fondo de Ojo , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
2.
Nat Chem Biol ; 9(8): 485-7, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23792734

RESUMEN

Whole-cell catalysts for non-natural chemical reactions will open new routes to sustainable production of chemicals. We designed a cytochrome 'P411' with unique serine-heme ligation that catalyzes efficient and selective olefin cyclopropanation in intact Escherichia coli cells. The mutation C400S in cytochrome P450(BM3) gives a signature ferrous CO Soret peak at 411 nm, abolishes monooxygenation activity, raises the resting-state Fe(III)-to-Fe(II) reduction potential and substantially improves NAD(P)H-driven activity.


Asunto(s)
Alquenos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Metano/análogos & derivados , Serina/metabolismo , Alquenos/química , Biocatálisis , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/genética , Escherichia coli/química , Escherichia coli/citología , Escherichia coli/metabolismo , Metano/química , Metano/metabolismo , Mutación , Serina/química
3.
Angew Chem Int Ed Engl ; 53(26): 6810-3, 2014 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-24802161

RESUMEN

Engineering enzymes capable of modes of activation unprecedented in nature will increase the range of industrially important molecules that can be synthesized through biocatalysis. However, low activity for a new function is often a limitation in adopting enzymes for preparative-scale synthesis, reaction with demanding substrates, or when a natural substrate is also present. By mutating the proximal ligand and other key active-site residues of the cytochrome P450 enzyme from Bacillus megaterium (P450-BM3), a highly active His-ligated variant of P450-BM3 that can be employed for the enantioselective synthesis of the levomilnacipran core was engineered. This enzyme, BM3-Hstar, catalyzes the cyclopropanation of N,N-diethyl-2-phenylacrylamide with an estimated initial rate of over 1000 turnovers per minute and can be used under aerobic conditions. Cyclopropanation activity is highly dependent on the electronic properties of the P450 proximal ligand, which can be used to tune this non-natural enzyme activity.


Asunto(s)
Ciclopropanos/síntesis química , Sistema Enzimático del Citocromo P-450/metabolismo , Histidina/metabolismo , Bacillus megaterium/enzimología , Dominio Catalítico , Ciclopropanos/química , Sistema Enzimático del Citocromo P-450/genética , Enzimas , Histidina/química , Milnaciprán , Mutagénesis Sitio-Dirigida , Ingeniería de Proteínas , Estereoisomerismo
4.
Sci Rep ; 14(1): 5181, 2024 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-38431751

RESUMEN

Atopic dermatitis (AD) is a common inflammatory skin condition that significantly affects patients' lives and imposes both economic and non-economic burdens. The precise societal and individual consequences of AD remain incompletely understood. This study aimed to characterize AD in Portuguese patients and assess its personal, familial, and societal implications, including health status and quality of life. The research, conducted from June 2019 to January 2020, involved 204 confirmed AD patients in Portugal, who completed a 70-question questionnaire. Results show that, on average, patients experienced a two-year delay in diagnosis, with two-thirds having allergic comorbidities. Late-onset AD (after age 20) was found to be correlated with worsening symptoms post-diagnosis. Globally, patients reported substantial effects on health, quality of life, and mental well-being. Effects include significant levels of anxiety, frustration and sleep disorders. Severe AD correlated with more suffering and reduced perceived health, indicating a link between disease severity and quality of life. Remarkably, despite questionable effectiveness, 92% of severe AD patients were prescribed antihistamines, while only 19% received biological treatments. In Portugal, delayed AD diagnosis hinders timely treatment, and despite its profound impact and high comorbidity rates, AD patients tend to remain undertreated. Recognizing the personal and societal repercussions is crucial for enhancing care, contributing to improving QoL, social functioning and global well-being.


Asunto(s)
Dermatitis Atópica , Humanos , Adulto Joven , Adulto , Dermatitis Atópica/diagnóstico , Calidad de Vida , Portugal/epidemiología , Comorbilidad , Piel , Índice de Severidad de la Enfermedad
5.
Infect Dis Model ; 2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37366483

RESUMEN

Successive generalisations of the basic SEIR model have been proposed to accommodate the different needs of the organisations handling the SARS-CoV-2 epidemic and the assessment of the public health measures adopted and named under the common umbrella of Non-Pharmaceutical Interventions (NPIs). So far, these generalisations have not been able to assess the ability of these measures to avoid infection by the SARS-CoV-2 and thus their contribution to contain the spread of the disease. This work proposes a new generalisation of SEIR model and includes a heterogeneous and age-related generation of infections that depends both on a probability that a contact generates the transmission of the disease and a contact rate. The results show (1) thanks to the universal wearing of facial coverings, the probability that a contact provokes the transmission of the disease was reduced by at least 50% and (2) the impact of the other NPI is so significant that otherwise Portugal would have gone into a non-sustainable situation of having 80% of its population infected in the first 300 days of the pandemic. This situation would have led to a number of deaths almost twenty times higher than the number that was actually recorded by December 26th, 2020. Moreover, the results suggest that even if the requirement of universal wearing of facial coverings was adopted sooner jointly with closing workplaces and resorting to teleworking would have postponed the peak of the incidence, altought the epidemic path would have result in a number of infections hardly managed by the National Health System. Complementary, results confirm that (3) the health authorities adopted a conservative approach on the criteria to consider an infected individual not infective any longer; and (4) the most effective NPIs and stringency levels either impacting on self-protection against infection or reducing the contacts that would eventually result in infection are, in decreasing order of importance, the use of Facial coverings, Workplace closing and Stay at home requirements.

6.
Chem Soc Rev ; 40(4): 2003-21, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21079862

RESUMEN

The development of new catalytic methods to functionalize carbon-hydrogen (C-H) bonds continues to progress at a rapid pace due to the significant economic and environmental benefits of these transformations over traditional synthetic methods. In nature, enzymes catalyze regio- and stereoselective C-H bond functionalization using transformations ranging from hydroxylation to hydroalkylation under ambient reaction conditions. The efficiency of these enzymes relative to analogous chemical processes has led to their increased use as biocatalysts in preparative and industrial applications. Furthermore, unlike small molecule catalysts, enzymes can be systematically optimized via directed evolution for a particular application and can be expressed in vivo to augment the biosynthetic capability of living organisms. While a variety of technical challenges must still be overcome for practical application of many enzymes for C-H bond functionalization, continued research on natural enzymes and on novel artificial metalloenzymes will lead to improved synthetic processes for efficient synthesis of complex molecules. In this critical review, we discuss the most prevalent mechanistic strategies used by enzymes to functionalize non-acidic C-H bonds, the application and evolution of these enzymes for chemical synthesis, and a number of potential biosynthetic capabilities uniquely enabled by these powerful catalysts (110 references).


Asunto(s)
Carbono/química , Hidrógeno/química , Oxigenasas de Función Mixta/metabolismo , Biocatálisis , Hidroliasas/metabolismo , Hidroxilación , Estereoisomerismo
7.
Sci Rep ; 11(1): 19617, 2021 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-34608201

RESUMEN

Successive generalisations of the basic SEIR model have been proposed to accommodate the different needs of the organisations handling the SARS-CoV-2 epidemic. These generalisations have not been able until today to represent the potential of the epidemic to overwhelm hospital capacity until today. This work builds on previous generalisations, including a new compartment for hospital occupancy that allows accounting for the infected patients that need specialised medical attention. Consequently, a deeper understanding of the hospitalisations rate and probability as well as of the recovery rates for hospitalised and non-hospitalised individuals is achieved, offering new information and predictions of crucial importance for the planning of the health systems and global epidemic response. Additionally, a new methodology to calibrate epidemic flows between compartments is proposed. We conclude that the two-step calibration procedure is able to recalibrate non-error-free data and showed crucial to reconstruct the series in a specific situation characterised by significant errors over the official recovery cases. The performed modelling also allowed us to understand how effective the several interventions (lockdown or other mobility restriction measures) were, offering insight for helping public authorities to set the timing and intensity of the measures in order to avoid the implosion of the health systems.


Asunto(s)
COVID-19/epidemiología , Hospitalización/estadística & datos numéricos , Modelos Estadísticos , Teorema de Bayes , COVID-19/patología , COVID-19/virología , Humanos , Pandemias , Portugal/epidemiología , Cuarentena , SARS-CoV-2/aislamiento & purificación
8.
Nutrients ; 12(5)2020 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-32455971

RESUMEN

A 14-Item Mediterranean Diet Adherence Screener (MEDAS) questionnaire was developed and validated in face-to-face interviews, but not via telephone. The aims of this study were to evaluate the validity and reliability of a telephone-administered version of the MEDAS as well as to validate the Portuguese version of the MEDAS questionnaire. A convenience community-based sample of adults (n = 224) participated in a three-stage survey. First, trained researchers administered MEDAS via a telephone. Second, the Portuguese version of Food Frequency Questionnaire (FFQ), and MEDAS were administered in a semi-structured face-to-face interview. Finally, MEDAS was again administered via telephone. The telephone-administered MEDAS questionnaire was compared with the face-to-face-version using several metrics. The telephone-administered MEDAS was significantly correlated with the face-to-face-administered MEDAS [r = 0.805, p < 0.001; interclass correlation coefficient (ICC) = 0.803, p < 0.001] and showed strong agreement (k = 0.60). The MEDAS scores that were obtained in the first and second telephone interviews were significantly correlated (r = 0.661, p < 0.001; ICC = 0.639, p < 0.001). The overall agreement between the Portuguese version of MEDAS and the FFQ-derived Mediterranean diet adherence score had a Cohen's k = 0.39. The telephone-administered version of MEDAS is a valid tool for assessing the adherence to the Mediterranean diet and acquiring data for large population-based studies.


Asunto(s)
Dieta Mediterránea/psicología , Cooperación del Paciente/psicología , Teléfono , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación Nutricional , Portugal , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Adulto Joven
10.
Arch Osteoporos ; 13(1): 22, 2018 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-29516239

RESUMEN

Using a large population database, we showed that fragility fractures were highly prevalent in senior women and were associated with significant physical disability. However, treatment rates were low because osteoporosis treatment was not prescribed or not agreed to by the majority of women with prevalent fragility fractures. PURPOSE: The purpose of the study is to estimate prevalence of fragility fractures (FF), risk factors, and treatment rates in senior women and to assess impact of FF on physical function and quality of life. METHODS: Women aged 65 years and older from the EpiReumaPt study (2011-2013) were evaluated. Rheumatologists collected data regarding FF, clinical risk factors for fractures, and osteoporosis (OP) treatment. Health-related quality of life (EQ5D) and physical function (HAQ) were analyzed. Peripheral dual-energy X-ray absorptiometry was performed. FF was defined as any self-reported low-impact fracture that occurred after 40 years of age. Prevalence estimates of FF were calculated. RESULTS: Among 3877 subjects evaluated in EpiReumaPt, 884 were senior women. The estimated prevalence of FF was 20.7%. Lower leg was the most frequent fracture site reported (37.8%) followed by wrist (18.6%). Only 7.1% of the senior women reporting a prevalent FF were under treatment for OP, and 13.9% never had treatment. OP treatment was not prescribed in 47.7% of FF women, and 23.4% refused treatment. Age (OR = 2.46, 95% CI 1.11-5.47), obesity (OR = 2.05, 95% CI 1.14-3.70), and low wrist BMD (OR = 2.29; 95% CI 1.20, 4.35; p = 0.012) were positively associated with prevalent FF. A significantly higher proportion of women in the lowest quintile of wrist bone mineral density reported FF (OR = 2.29, 95% CI 1.20-4.35). FF were associated with greater physical disability (ß = 0.33, 95% CI 0.13-0.51) independent of other comorbidities. CONCLUSION: FF was frequently reported among senior women as an important cause of physical disability. However, the prevalence of OP treatment was low, which constitutes a public health problem in this vulnerable group.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Costo de Enfermedad , Mal Uso de los Servicios de Salud/estadística & datos numéricos , Osteoporosis Posmenopáusica , Fracturas Osteoporóticas , Calidad de Vida , Absorciometría de Fotón/métodos , Anciano , Densidad Ósea , Femenino , Humanos , Evaluación de Necesidades , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/diagnóstico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/epidemiología , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/fisiopatología , Fracturas Osteoporóticas/prevención & control , Fracturas Osteoporóticas/psicología , Portugal/epidemiología , Prevalencia , Factores de Riesgo , Salud de la Mujer
11.
Front Nutr ; 4: 25, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28660194

RESUMEN

OBJECTIVE: We aimed to identify dietary patterns (DPs) of Portuguese adults, to assess their socioeconomic, demographic, lifestyle determinants, and to identify their impact on health. DESIGN: EpiDoC 2 study included 10,153 Portuguese adults from the EpiDoC Cohort, a population-based study. In this study, trained research assistants using computer-assisted telephone interview collected socioeconomic, demographic, dietary, lifestyles, and health information from March 2013 to July 2015. Cluster analysis was performed, based on questions regarding the number of meals, weekly frequency of soup consumption, vegetables, fruit, meat, fish, dairy products, and daily water intake. Factors associated with DP were identified through logistic regression models. RESULTS: Two DPs were identified: the "meat dietary pattern" and the "fruit & vegetables dietary pattern." After multivariable adjustment, women (OR = 0.52; p < 0.001), older adults (OR = 0.97; p < 0.001), and individuals with more years of education (OR = 0.96; p = 0.025) were less likely to adopt the "meat dietary pattern," while individuals in a situation of job insecurity/unemployment (OR = 1.49; p = 0.013), Azores island residents (OR = 1.40; p = 0.026), current smoking (OR = 1.58; p = 0.001), daily alcohol intake (OR = 1.46; p = 0.023), and physically inactive (OR = 1.86; p < 0.001) were positively and significantly associated with "meat dietary pattern." Moreover, individuals with depression symptoms (OR = 1.50; p = 0.018) and the ones who did lower number of medical appointments in the previous year (OR = 0.98; p = 0.025) were less likely to report this DP. CONCLUSION: Our results suggest that unhealthy DPs (meat DP) are part of a lifestyle behavior that includes physical inactivity, smoking habits, and alcohol consumption. Moreover, depression symptoms are also associated with unhealthy DPs.

12.
JMIR Res Protoc ; 6(3): e40, 2017 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-28288956

RESUMEN

BACKGROUND: The limited or uncertain access to adequate food in elderly people includes not only economic restrictions but also inability of food utilization due to functional or cognitive impairment, health problems, and illiteracy. OBJECTIVE: The aim of this work is to present the protocol of the randomized controlled trial Saúde.Come Senior, an educational and motivational television (TV)-based intervention to promote healthy lifestyles and decrease food insecurity in elderly people. METHODS: A randomized controlled study will be conducted in subjects aged 60 years and older with food insecurity, identified at 17 primary care centers in the Lisboa e Vale do Tejo health region in Lisbon, Portugal. The primary outcome will be the changes in participants' food insecurity score (evaluated by the Household Food Insecurity Scale) at 3 months. Change in other outcomes will be assessed (dietary habits, nutritional status, physical activity, health status, and clinical outcomes). Subjects will be followed over 6 months; the intervention will last 3 months. Data collection will be performed at 3 different time points (baseline, end of intervention at 3 months, and follow-up at 6 months). The intervention is based on an interactive TV app with an educational and motivational program specifically developed for the elderly that has weekly themes and includes daily content in video format: (1) nutrition and diet tips for healthy eating, (2) healthy, easy to cook and low-cost recipes, and (3) physical exercise programs. Furthermore, brief reminders on health behaviors will also be broadcasted through the TV app. The total duration of the study will be 6 months. The intervention is considered to be effective and meaningful if 50% of the individuals in the experimental group have a decrease of 1 point in the food insecurity score, all the remaining being unchanged. We expect to include and randomize 282 (141 experimental and 141 control) elderly with food insecurity. We will recruit a total of 1,128 subjects considering that 50% of the target individuals are food insecure (based on INFOFAMÍLIA Survey) (567) and about 50% of those will adhere to the study (282). RESULTS: The randomized controlled trial with the 12-week home-based intervention with a comprehensive program on healthy eating and physical activity delivery is planned to start recruiting participants at the end of 2017. CONCLUSIONS: This study will assess the efficacy of this innovative tool (Saúde.Come Senior) for disseminating relevant health information, modifying behaviors, and decreasing food insecurity in an easy, low-cost, and massive way.

13.
RMD Open ; 2(1): e000166, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26848402

RESUMEN

OBJECTIVES: To estimate the national prevalence of rheumatic and musculoskeletal diseases (RMDs) in the adult Portuguese population and to determine their impact on health-related quality of life (HRQoL), physical function, anxiety and depression. METHODS: EpiReumaPt is a national health survey with a three-stage approach. First, 10 661 adult participants were randomly selected. Trained interviewers undertook structured face-to-face questionnaires that included screening for RMDs and assessments of health-related quality of life, physical function, anxiety and depression. Second, positive screenings for ≥1 RMD plus 20% negative screenings were invited to be evaluated by a rheumatologist. Finally, three rheumatologists revised all the information and confirmed the diagnoses according to validated criteria. Estimates were computed as weighted proportions, taking the sampling design into account. RESULTS: The disease-specific prevalence rates (and 95% CIs) of RMDs in the adult Portuguese population were: low back pain, 26.4% (23.3% to 29.5%); periarticular disease, 15.8% (13.5% to 18.0%); knee osteoarthritis (OA), 12.4% (11.0% to 13.8%); osteoporosis, 10.2% (9.0% to 11.3%); hand OA, 8.7% (7.5% to 9.9%); hip OA, 2.9% (2.3% to 3.6%); fibromyalgia, 1.7% (1.1% to 2.1%); spondyloarthritis, 1.6% (1.2% to 2.1%); gout, 1.3% (1.0% to 1.6%); rheumatoid arthritis, 0.7% (0.5% to 0.9%); systemic lupus erythaematosus, 0.1% (0.1% to 0.2%) and polymyalgia rheumatica, 0.1% (0.0% to 0.2%). After multivariable adjustment, participants with RMDs had significantly lower EQ5D scores (ß=-0.09; p<0.001) and higher HAQ scores (ß=0.13; p<0.001) than participants without RMDs. RMDs were also significantly associated with the presence of anxiety symptoms (OR=3.5; p=0.006). CONCLUSIONS: RMDs are highly prevalent in Portugal and are associated not only with significant physical function and mental health impairment but also with poor HRQoL, leading to more health resource consumption. The EpiReumaPt study emphasises the burden of RMDs in Portugal and the need to increase RMD awareness, being a strong argument to encourage policymakers to increase the amount of resources allocated to the treatment of rheumatic patients.

14.
Science ; 339(6117): 307-10, 2013 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-23258409

RESUMEN

Transition metal-catalyzed transfers of carbenes, nitrenes, and oxenes are powerful methods for functionalizing C=C and C-H bonds. Nature has evolved a diverse toolbox for oxene transfers, as exemplified by the myriad monooxygenation reactions catalyzed by cytochrome P450 enzymes. The isoelectronic carbene transfer to olefins, a widely used C-C bond-forming reaction in organic synthesis, has no biological counterpart. Here we report engineered variants of cytochrome P450(BM3) that catalyze highly diastereo- and enantioselective cyclopropanation of styrenes from diazoester reagents via putative carbene transfer. This work highlights the capacity to adapt existing enzymes for the catalysis of synthetically important reactions not previously observed in nature.


Asunto(s)
Alquenos/química , Ciclopropanos/química , Sistema Enzimático del Citocromo P-450/química , Metano/análogos & derivados , Bacillus megaterium/enzimología , Catálisis , Sistema Enzimático del Citocromo P-450/genética , Metano/química , Modelos Químicos , Ingeniería de Proteínas , Estereoisomerismo
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